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Commit 8b469209 authored by Alan Donovan's avatar Alan Donovan
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cmd/vendor: add x/tools/go/analysis/cmd/vet-lite + deps 

This change adds the vet-lite command (the future cmd/vet) and all its
dependencies from x/tools, but not its tests and their dependencies.
It was created with these commands:

  $ (cd $GOPATH/src/golang.org/x/tools && git checkout c76e1ad)
  $ cd GOROOT/src/cmd
  $ govendor add $(go list -deps golang.org/x/tools/go/analysis/cmd/vet-lite | grep golang.org/x/tools)
  $ rm -fr $(find vendor/golang.org/x/tools/ -name testdata)
  $ rm $(find vendor/golang.org/x/tools/ -name \*_test.go)

I feel sure I am holding govendor wrong. Please advise.

A followup CL will make cmd/vet behave like vet-lite, initially just
for users that opt in, and soon after for all users, at which point
cmd/vet will be replaced in its entirety by a copy of vet-lite's small
main.go.

In the meantime, anyone can try the new tool using these commands:

 $ go build cmd/vendor/golang.org/x/tools/go/analysis/cmd/vet-lite
 $ export GOVETTOOL=$(which vet-lite)
 $ go vet your/project/...

Change-Id: Iea168111a32ce62f82f9fb706385ca0f368bc869
Reviewed-on: https://go-review.googlesource.com/c/147444Reviewed-by: default avatarRuss Cox <rsc@golang.org>
parent aa9bcea3
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src/cmd/vendor/golang.org/x/tools/LICENSE 0 → 100644
View file @ 8b469209
Copyright (c) 2009 The Go Authors. All rights reserved.
Redistribution and use in source and binary forms, with or without
modification, are permitted provided that the following conditions are
met:
* Redistributions of source code must retain the above copyright
notice, this list of conditions and the following disclaimer.
* Redistributions in binary form must reproduce the above
copyright notice, this list of conditions and the following disclaimer
in the documentation and/or other materials provided with the
distribution.
* Neither the name of Google Inc. nor the names of its
contributors may be used to endorse or promote products derived from
this software without specific prior written permission.
THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
"AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
src/cmd/vendor/golang.org/x/tools/PATENTS 0 → 100644
View file @ 8b469209
Additional IP Rights Grant (Patents)
"This implementation" means the copyrightable works distributed by
Google as part of the Go project.
Google hereby grants to You a perpetual, worldwide, non-exclusive,
no-charge, royalty-free, irrevocable (except as stated in this section)
patent license to make, have made, use, offer to sell, sell, import,
transfer and otherwise run, modify and propagate the contents of this
implementation of Go, where such license applies only to those patent
claims, both currently owned or controlled by Google and acquired in
the future, licensable by Google that are necessarily infringed by this
implementation of Go. This grant does not include claims that would be
infringed only as a consequence of further modification of this
implementation. If you or your agent or exclusive licensee institute or
order or agree to the institution of patent litigation against any
entity (including a cross-claim or counterclaim in a lawsuit) alleging
that this implementation of Go or any code incorporated within this
implementation of Go constitutes direct or contributory patent
infringement, or inducement of patent infringement, then any patent
rights granted to you under this License for this implementation of Go
shall terminate as of the date such litigation is filed.
src/cmd/vendor/golang.org/x/tools/go/analysis/analysis.go 0 → 100644
View file @ 8b469209
package analysis
import (
"flag"
"fmt"
"go/ast"
"go/token"
"go/types"
"reflect"
)
// An Analyzer describes an analysis function and its options.
type Analyzer struct {
// The Name of the analyzer must be a valid Go identifier
// as it may appear in command-line flags, URLs, and so on.
Name string
// Doc is the documentation for the analyzer.
// The part before the first "\n\n" is the title
// (no capital or period, max ~60 letters).
Doc string
// Flags defines any flags accepted by the analyzer.
// The manner in which these flags are exposed to the user
// depends on the driver which runs the analyzer.
Flags flag.FlagSet
// Run applies the analyzer to a package.
// It returns an error if the analyzer failed.
//
// On success, the Run function may return a result
// computed by the Analyzer; its type must match ResultType.
// The driver makes this result available as an input to
// another Analyzer that depends directly on this one (see
// Requires) when it analyzes the same package.
//
// To pass analysis results between packages (and thus
// potentially between address spaces), use Facts, which are
// serializable.
Run func(*Pass) (interface{}, error)
// RunDespiteErrors allows the driver to invoke
// the Run method of this analyzer even on a
// package that contains parse or type errors.
RunDespiteErrors bool
// Requires is a set of analyzers that must run successfully
// before this one on a given package. This analyzer may inspect
// the outputs produced by each analyzer in Requires.
// The graph over analyzers implied by Requires edges must be acyclic.
//
// Requires establishes a "horizontal" dependency between
// analysis passes (different analyzers, same package).
Requires []*Analyzer
// ResultType is the type of the optional result of the Run function.
ResultType reflect.Type
// FactTypes indicates that this analyzer imports and exports
// Facts of the specified concrete types.
// An analyzer that uses facts may assume that its import
// dependencies have been similarly analyzed before it runs.
// Facts must be pointers.
//
// FactTypes establishes a "vertical" dependency between
// analysis passes (same analyzer, different packages).
FactTypes []Fact
}
func (a *Analyzer) String() string { return a.Name }
// A Pass provides information to the Run function that
// applies a specific analyzer to a single Go package.
//
// It forms the interface between the analysis logic and the driver
// program, and has both input and an output components.
//
// As in a compiler, one pass may depend on the result computed by another.
//
// The Run function should not call any of the Pass functions concurrently.
type Pass struct {
Analyzer *Analyzer // the identity of the current analyzer
// syntax and type information
Fset *token.FileSet // file position information
Files []*ast.File // the abstract syntax tree of each file
OtherFiles []string // names of non-Go files of this package
Pkg *types.Package // type information about the package
TypesInfo *types.Info // type information about the syntax trees
// Report reports a Diagnostic, a finding about a specific location
// in the analyzed source code such as a potential mistake.
// It may be called by the Run function.
Report func(Diagnostic)
// ResultOf provides the inputs to this analysis pass, which are
// the corresponding results of its prerequisite analyzers.
// The map keys are the elements of Analysis.Required,
// and the type of each corresponding value is the required
// analysis's ResultType.
ResultOf map[*Analyzer]interface{}
// -- facts --
// ImportObjectFact retrieves a fact associated with obj.
// Given a value ptr of type *T, where *T satisfies Fact,
// ImportObjectFact copies the value to *ptr.
//
// ImportObjectFact panics if called after the pass is complete.
// ImportObjectFact is not concurrency-safe.
ImportObjectFact func(obj types.Object, fact Fact) bool
// ImportPackageFact retrieves a fact associated with package pkg,
// which must be this package or one of its dependencies.
// See comments for ImportObjectFact.
ImportPackageFact func(pkg *types.Package, fact Fact) bool
// ExportObjectFact associates a fact of type *T with the obj,
// replacing any previous fact of that type.
//
// ExportObjectFact panics if it is called after the pass is
// complete, or if obj does not belong to the package being analyzed.
// ExportObjectFact is not concurrency-safe.
ExportObjectFact func(obj types.Object, fact Fact)
// ExportPackageFact associates a fact with the current package.
// See comments for ExportObjectFact.
ExportPackageFact func(fact Fact)
/* Further fields may be added in future. */
// For example, suggested or applied refactorings.
}
// Reportf is a helper function that reports a Diagnostic using the
// specified position and formatted error message.
func (pass *Pass) Reportf(pos token.Pos, format string, args ...interface{}) {
msg := fmt.Sprintf(format, args...)
pass.Report(Diagnostic{Pos: pos, Message: msg})
}
func (pass *Pass) String() string {
return fmt.Sprintf("%s@%s", pass.Analyzer.Name, pass.Pkg.Path())
}
// A Fact is an intermediate fact produced during analysis.
//
// Each fact is associated with a named declaration (a types.Object) or
// with a package as a whole. A single object or package may have
// multiple associated facts, but only one of any particular fact type.
//
// A Fact represents a predicate such as "never returns", but does not
// represent the subject of the predicate such as "function F" or "package P".
//
// Facts may be produced in one analysis pass and consumed by another
// analysis pass even if these are in different address spaces.
// If package P imports Q, all facts about Q produced during
// analysis of that package will be available during later analysis of P.
// Facts are analogous to type export data in a build system:
// just as export data enables separate compilation of several passes,
// facts enable "separate analysis".
//
// Each pass (a, p) starts with the set of facts produced by the
// same analyzer a applied to the packages directly imported by p.
// The analysis may add facts to the set, and they may be exported in turn.
// An analysis's Run function may retrieve facts by calling
// Pass.Import{Object,Package}Fact and update them using
// Pass.Export{Object,Package}Fact.
//
// A fact is logically private to its Analysis. To pass values
// between different analyzers, use the results mechanism;
// see Analyzer.Requires, Analyzer.ResultType, and Pass.ResultOf.
//
// A Fact type must be a pointer.
// Facts are encoded and decoded using encoding/gob.
// A Fact may implement the GobEncoder/GobDecoder interfaces
// to customize its encoding. Fact encoding should not fail.
//
// A Fact should not be modified once exported.
type Fact interface {
AFact() // dummy method to avoid type errors
}
// A Diagnostic is a message associated with a source location.
//
// An Analyzer may return a variety of diagnostics; the optional Category,
// which should be a constant, may be used to classify them.
// It is primarily intended to make it easy to look up documentation.
type Diagnostic struct {
Pos token.Pos
Category string // optional
Message string
}
src/cmd/vendor/golang.org/x/tools/go/analysis/cmd/vet-lite/main.go 0 → 100644
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// The vet-lite command is a driver for static checkers conforming to
// the golang.org/x/tools/go/analysis API. It must be run by go vet:
//
// $ GOVETTOOL=$(which vet-lite) go vet
//
// For a checker also capable of running standalone, use multichecker.
package main
import (
"flag"
"log"
"strings"
"golang.org/x/tools/go/analysis"
"golang.org/x/tools/go/analysis/internal/analysisflags"
"golang.org/x/tools/go/analysis/internal/unitchecker"
"golang.org/x/tools/go/analysis/passes/asmdecl"
"golang.org/x/tools/go/analysis/passes/assign"
"golang.org/x/tools/go/analysis/passes/atomic"
"golang.org/x/tools/go/analysis/passes/bools"
"golang.org/x/tools/go/analysis/passes/buildtag"
"golang.org/x/tools/go/analysis/passes/cgocall"
"golang.org/x/tools/go/analysis/passes/composite"
"golang.org/x/tools/go/analysis/passes/copylock"
"golang.org/x/tools/go/analysis/passes/httpresponse"
"golang.org/x/tools/go/analysis/passes/loopclosure"
"golang.org/x/tools/go/analysis/passes/lostcancel"
"golang.org/x/tools/go/analysis/passes/nilfunc"
"golang.org/x/tools/go/analysis/passes/pkgfact"
"golang.org/x/tools/go/analysis/passes/printf"
"golang.org/x/tools/go/analysis/passes/shift"
"golang.org/x/tools/go/analysis/passes/stdmethods"
"golang.org/x/tools/go/analysis/passes/structtag"
"golang.org/x/tools/go/analysis/passes/tests"
"golang.org/x/tools/go/analysis/passes/unreachable"
"golang.org/x/tools/go/analysis/passes/unsafeptr"
"golang.org/x/tools/go/analysis/passes/unusedresult"
)
var analyzers = []*analysis.Analyzer{
// For now, just the traditional vet suite:
asmdecl.Analyzer,
assign.Analyzer,
atomic.Analyzer,
bools.Analyzer,
buildtag.Analyzer,
cgocall.Analyzer,
composite.Analyzer,
copylock.Analyzer,
httpresponse.Analyzer,
loopclosure.Analyzer,
lostcancel.Analyzer,
nilfunc.Analyzer,
pkgfact.Analyzer,
printf.Analyzer,
// shadow.Analyzer, // experimental; not enabled by default
shift.Analyzer,
stdmethods.Analyzer,
structtag.Analyzer,
tests.Analyzer,
unreachable.Analyzer,
unsafeptr.Analyzer,
unusedresult.Analyzer,
}
func main() {
log.SetFlags(0)
log.SetPrefix("vet: ")
if err := analysis.Validate(analyzers); err != nil {
log.Fatal(err)
}
analyzers = analysisflags.Parse(analyzers, true)
args := flag.Args()
if len(args) != 1 || !strings.HasSuffix(args[0], ".cfg") {
log.Fatalf("invalid command: want .cfg file (this reduced version of vet is intended to be run only by the 'go vet' command)")
}
unitchecker.Main(args[0], analyzers)
}
src/cmd/vendor/golang.org/x/tools/go/analysis/doc.go 0 → 100644
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/*
The analysis package defines the interface between a modular static
analysis and an analysis driver program.
THIS INTERFACE IS EXPERIMENTAL AND SUBJECT TO CHANGE.
We aim to finalize it by November 2018.
Background
A static analysis is a function that inspects a package of Go code and
reports a set of diagnostics (typically mistakes in the code), and
perhaps produces other results as well, such as suggested refactorings
or other facts. An analysis that reports mistakes is informally called a
"checker". For example, the printf checker reports mistakes in
fmt.Printf format strings.
A "modular" analysis is one that inspects one package at a time but can
save information from a lower-level package and use it when inspecting a
higher-level package, analogous to separate compilation in a toolchain.
The printf checker is modular: when it discovers that a function such as
log.Fatalf delegates to fmt.Printf, it records this fact, and checks
calls to that function too, including calls made from another package.
By implementing a common interface, checkers from a variety of sources
can be easily selected, incorporated, and reused in a wide range of
driver programs including command-line tools (such as vet), text editors and
IDEs, build and test systems (such as go build, Bazel, or Buck), test
frameworks, code review tools, code-base indexers (such as SourceGraph),
documentation viewers (such as godoc), batch pipelines for large code
bases, and so on.
Analyzer
The primary type in the API is Analyzer. An Analyzer statically
describes an analysis function: its name, documentation, flags,
relationship to other analyzers, and of course, its logic.
To define an analysis, a user declares a (logically constant) variable
of type Analyzer. Here is a typical example from one of the analyzers in
the go/analysis/passes/ subdirectory:
package unusedresult
var Analyzer = &analysis.Analyzer{
Name: "unusedresult",
Doc: "check for unused results of calls to some functions",
Run: run,
...
}
func run(pass *analysis.Pass) (interface{}, error) {
...
}
An analysis driver is a program such as vet that runs a set of
analyses and prints the diagnostics that they report.
The driver program must import the list of Analyzers it needs.
Typically each Analyzer resides in a separate package.
To add a new Analyzer to an existing driver, add another item to the list:
import ( "unusedresult"; "nilness"; "printf" )
var analyses = []*analysis.Analyzer{
unusedresult.Analyzer,
nilness.Analyzer,
printf.Analyzer,
}
A driver may use the name, flags, and documentation to provide on-line
help that describes the analyses its performs.
The vet command, shown below, is an example of a driver that runs
multiple analyzers. It is based on the multichecker package
(see the "Standalone commands" section for details).
$ go build golang.org/x/tools/cmd/vet
$ ./vet help
vet is a tool for static analysis of Go programs.
Usage: vet [-flag] [package]
Registered analyzers:
asmdecl report mismatches between assembly files and Go declarations
assign check for useless assignments
atomic check for common mistakes using the sync/atomic package
...
unusedresult check for unused results of calls to some functions
$ ./vet help unusedresult
unusedresult: check for unused results of calls to some functions
Analyzer flags:
-unusedresult.funcs value
comma-separated list of functions whose results must be used (default Error,String)
-unusedresult.stringmethods value
comma-separated list of names of methods of type func() string whose results must be used
Some functions like fmt.Errorf return a result and have no side effects,
so it is always a mistake to discard the result. This analyzer reports
calls to certain functions in which the result of the call is ignored.
The set of functions may be controlled using flags.
The Analyzer type has more fields besides those shown above:
type Analyzer struct {
Name string
Doc string
Flags flag.FlagSet
Run func(*Pass) (interface{}, error)
RunDespiteErrors bool
ResultType reflect.Type
Requires []*Analyzer
FactTypes []Fact
}
The Flags field declares a set of named (global) flag variables that
control analysis behavior. Unlike vet, analysis flags are not declared
directly in the command line FlagSet; it is up to the driver to set the
flag variables. A driver for a single analysis, a, might expose its flag
f directly on the command line as -f, whereas a driver for multiple
analyses might prefix the flag name by the analysis name (-a.f) to avoid
ambiguity. An IDE might expose the flags through a graphical interface,
and a batch pipeline might configure them from a config file.
See the "findcall" analyzer for an example of flags in action.
The RunDespiteErrors flag indicates whether the analysis is equipped to
handle ill-typed code. If not, the driver will skip the analysis if
there were parse or type errors.
The optional ResultType field specifies the type of the result value
computed by this analysis and made available to other analyses.
The Requires field specifies a list of analyses upon which
this one depends and whose results it may access, and it constrains the
order in which a driver may run analyses.
The FactTypes field is discussed in the section on Modularity.
The analysis package provides a Validate function to perform basic
sanity checks on an Analyzer, such as that its Requires graph is
acyclic, its fact and result types are unique, and so on.
Finally, the Run field contains a function to be called by the driver to
execute the analysis on a single package. The driver passes it an
instance of the Pass type.
Pass
A Pass describes a single unit of work: the application of a particular
Analyzer to a particular package of Go code.
The Pass provides information to the Analyzer's Run function about the
package being analyzed, and provides operations to the Run function for
reporting diagnostics and other information back to the driver.
type Pass struct {
Fset *token.FileSet
Files []*ast.File
OtherFiles []string
Pkg *types.Package
TypesInfo *types.Info
ResultOf map[*Analyzer]interface{}
Report func(Diagnostic)
...
}
The Fset, Files, Pkg, and TypesInfo fields provide the syntax trees,
type information, and source positions for a single package of Go code.
The OtherFiles field provides the names, but not the contents, of non-Go
files such as assembly that are part of this package. See the "asmdecl"
or "buildtags" analyzers for examples of loading non-Go files and report
diagnostics against them.
The ResultOf field provides the results computed by the analyzers
required by this one, as expressed in its Analyzer.Requires field. The
driver runs the required analyzers first and makes their results
available in this map. Each Analyzer must return a value of the type
described in its Analyzer.ResultType field.
For example, the "ctrlflow" analyzer returns a *ctrlflow.CFGs, which
provides a control-flow graph for each function in the package (see
golang.org/x/tools/go/cfg); the "inspect" analyzer returns a value that
enables other Analyzers to traverse the syntax trees of the package more
efficiently; and the "buildssa" analyzer constructs an SSA-form
intermediate representation.
Each of these Analyzers extends the capabilities of later Analyzers
without adding a dependency to the core API, so an analysis tool pays
only for the extensions it needs.
The Report function emits a diagnostic, a message associated with a
source position. For most analyses, diagnostics are their primary
result.
For convenience, Pass provides a helper method, Reportf, to report a new
diagnostic by formatting a string.
Diagnostic is defined as:
type Diagnostic struct {
Pos token.Pos
Category string // optional
Message string
}
The optional Category field is a short identifier that classifies the
kind of message when an analysis produces several kinds of diagnostic.
Most Analyzers inspect typed Go syntax trees, but a few, such as asmdecl
and buildtag, inspect the raw text of Go source files or even non-Go
files such as assembly. To report a diagnostic against a line of a
raw text file, use the following sequence:
content, err := ioutil.ReadFile(filename)
if err != nil { ... }
tf := fset.AddFile(filename, -1, len(content))
tf.SetLinesForContent(content)
...
pass.Reportf(tf.LineStart(line), "oops")
Modular analysis with Facts
To improve efficiency and scalability, large programs are routinely
built using separate compilation: units of the program are compiled
separately, and recompiled only when one of their dependencies changes;
independent modules may be compiled in parallel. The same technique may
be applied to static analyses, for the same benefits. Such analyses are
described as "modular".
A compiler’s type checker is an example of a modular static analysis.
Many other checkers we would like to apply to Go programs can be
understood as alternative or non-standard type systems. For example,
vet's printf checker infers whether a function has the "printf wrapper"
type, and it applies stricter checks to calls of such functions. In
addition, it records which functions are printf wrappers for use by
later analysis units to identify other printf wrappers by induction.
A result such as “f is a printf wrapper” that is not interesting by
itself but serves as a stepping stone to an interesting result (such as
a diagnostic) is called a "fact".
The analysis API allows an analysis to define new types of facts, to
associate facts of these types with objects (named entities) declared
within the current package, or with the package as a whole, and to query
for an existing fact of a given type associated with an object or
package.
An Analyzer that uses facts must declare their types:
var Analyzer = &analysis.Analyzer{
Name: "printf",
FactTypes: []reflect.Type{reflect.TypeOf(new(isWrapper))},
...
}
type isWrapper struct{} // => *types.Func f “is a printf wrapper”
A driver program ensures that facts for a pass’s dependencies are
generated before analyzing the pass and are responsible for propagating
facts between from one pass to another, possibly across address spaces.
Consequently, Facts must be serializable. The API requires that drivers
use the gob encoding, an efficient, robust, self-describing binary
protocol. A fact type may implement the GobEncoder/GobDecoder interfaces
if the default encoding is unsuitable. Facts should be stateless.
The Pass type has functions to import and export facts,
associated either with an object or with a package:
type Pass struct {
...
ExportObjectFact func(types.Object, Fact)
ImportObjectFact func(types.Object, Fact) bool
ExportPackageFact func(fact Fact)
ImportPackageFact func(*types.Package, Fact) bool
}
An Analyzer may only export facts associated with the current package or
its objects, though it may import facts from any package or object that
is an import dependency of the current package.
Conceptually, ExportObjectFact(obj, fact) inserts fact into a hidden map keyed by
the pair (obj, TypeOf(fact)), and the ImportObjectFact function
retrieves the entry from this map and copies its value into the variable
pointed to by fact. This scheme assumes that the concrete type of fact
is a pointer; this assumption is checked by the Validate function.
See the "printf" analyzer for an example of object facts in action.
Testing an Analyzer
The analysistest subpackage provides utilities for testing an Analyzer.
In a few lines of code, it is possible to run an analyzer on a package
of testdata files and check that it reported all the expected
diagnostics and facts (and no more). Expectations are expressed using
"// want ..." comments in the input code.
Standalone commands
Analyzers are provided in the form of packages that a driver program is
expected to import. The vet command imports a set of several analyses,
but users may wish to define their own analysis commands that perform
additional checks. To simplify the task of creating an analysis command,
either for a single analyzer or for a whole suite, we provide the
singlechecker and multichecker subpackages.
The singlechecker package provides the main function for a command that
runs one analysis. By convention, each analyzer such as
go/passes/findcall should be accompanied by a singlechecker-based
command such as go/analysis/passes/findcall/cmd/findcall, defined in its
entirety as:
package main
import (
"golang.org/x/tools/go/analysis/passes/findcall"
"golang.org/x/tools/go/analysis/singlechecker"
)
func main() { singlechecker.Main(findcall.Analyzer) }
A tool that provides multiple analyzers can use multichecker in a
similar way, giving it the list of Analyzers.
*/
package analysis
src/cmd/vendor/golang.org/x/tools/go/analysis/internal/analysisflags/flags.go 0 → 100644
View file @ 8b469209
// Copyright 2018 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
// Package analysisflags defines helpers for processing flags of
// analysis driver tools.
package analysisflags
import (
"crypto/sha256"
"encoding/json"
"flag"
"fmt"
"io"
"log"
"os"
"strconv"
"golang.org/x/tools/go/analysis"
)
// Parse creates a flag for each of the analyzer's flags,
// including (in multi mode) an --analysis.enable flag,
// parses the flags, then filters and returns the list of
// analyzers enabled by flags.
func Parse(analyzers []*analysis.Analyzer, multi bool) []*analysis.Analyzer {
// Connect each analysis flag to the command line as -analysis.flag.
type analysisFlag struct {
Name string
Bool bool
Usage string
}
var analysisFlags []analysisFlag
enabled := make(map[*analysis.Analyzer]*triState)
for _, a := range analyzers {
var prefix string
// Add -analysis.enable flag.
if multi {
prefix = a.Name + "."
enable := new(triState)
enableName := prefix + "enable"
enableUsage := "enable " + a.Name + " analysis"
flag.Var(enable, enableName, enableUsage)
enabled[a] = enable
analysisFlags = append(analysisFlags, analysisFlag{enableName, true, enableUsage})
}
a.Flags.VisitAll(func(f *flag.Flag) {
if !multi && flag.Lookup(f.Name) != nil {
log.Printf("%s flag -%s would conflict with driver; skipping", a.Name, f.Name)
return
}
name := prefix + f.Name
flag.Var(f.Value, name, f.Usage)
var isBool bool
if b, ok := f.Value.(interface{ IsBoolFlag() bool }); ok {
isBool = b.IsBoolFlag()
}
analysisFlags = append(analysisFlags, analysisFlag{name, isBool, f.Usage})
})
}
// standard flags: -flags, -V.
printflags := flag.Bool("flags", false, "print analyzer flags in JSON")
addVersionFlag()
flag.Parse() // (ExitOnError)
// -flags: print flags so that go vet knows which ones are legitimate.
if *printflags {
data, err := json.MarshalIndent(analysisFlags, "", "\t")
if err != nil {
log.Fatal(err)
}
os.Stdout.Write(data)
os.Exit(0)
}
// If any --foo.enable flag is true, run only those analyzers. Otherwise,
// if any --foo.enable flag is false, run all but those analyzers.
if multi {
var hasTrue, hasFalse bool
for _, ts := range enabled {
switch *ts {
case setTrue:
hasTrue = true
case setFalse:
hasFalse = true
}
}
var keep []*analysis.Analyzer
if hasTrue {
for _, a := range analyzers {
if *enabled[a] == setTrue {
keep = append(keep, a)
}
}
analyzers = keep
} else if hasFalse {
for _, a := range analyzers {
if *enabled[a] != setFalse {
keep = append(keep, a)
}
}
analyzers = keep
}
}
return analyzers
}
// addVersionFlag registers a -V flag that, if set,
// prints the executable version and exits 0.
//
// It is a variable not a function to permit easy
// overriding in the copy vendored in $GOROOT/src/cmd/vet:
//
// func init() { addVersionFlag = objabi.AddVersionFlag }
var addVersionFlag = func() {
flag.Var(versionFlag{}, "V", "print version and exit")
}
// versionFlag minimally complies with the -V protocol required by "go vet".
type versionFlag struct{}
func (versionFlag) IsBoolFlag() bool { return true }
func (versionFlag) Get() interface{} { return nil }
func (versionFlag) String() string { return "" }
func (versionFlag) Set(s string) error {
if s != "full" {
log.Fatalf("unsupported flag value: -V=%s", s)
}
// This replicates the miminal subset of
// cmd/internal/objabi.AddVersionFlag, which is private to the
// go tool yet forms part of our command-line interface.
// TODO(adonovan): clarify the contract.
// Print the tool version so the build system can track changes.
// Formats:
// $progname version devel ... buildID=...
// $progname version go1.9.1
progname := os.Args[0]
f, err := os.Open(progname)
if err != nil {
log.Fatal(err)
}
h := sha256.New()
if _, err := io.Copy(h, f); err != nil {
log.Fatal(err)
}
f.Close()
fmt.Printf("%s version devel comments-go-here buildID=%02x\n",
progname, string(h.Sum(nil)))
os.Exit(0)
return nil
}
// A triState is a boolean that knows whether
// it has been set to either true or false.
// It is used to identify whether a flag appears;
// the standard boolean flag cannot
// distinguish missing from unset.
// It also satisfies flag.Value.
type triState int
const (
unset triState = iota
setTrue
setFalse
)
func triStateFlag(name string, value triState, usage string) *triState {
flag.Var(&value, name, usage)
return &value
}
// triState implements flag.Value, flag.Getter, and flag.boolFlag.
// They work like boolean flags: we can say vet -printf as well as vet -printf=true
func (ts *triState) Get() interface{} {
return *ts == setTrue
}
func (ts triState) isTrue() bool {
return ts == setTrue
}
func (ts *triState) Set(value string) error {
b, err := strconv.ParseBool(value)
if err != nil {
// This error message looks poor but package "flag" adds
// "invalid boolean value %q for -foo.enable: %s"
return fmt.Errorf("want true or false")
}
if b {
*ts = setTrue
} else {
*ts = setFalse
}
return nil
}
func (ts *triState) String() string {
switch *ts {
case unset:
return "true"
case setTrue:
return "true"
case setFalse:
return "false"
}
panic("not reached")
}
func (ts triState) IsBoolFlag() bool {
return true
}
src/cmd/vendor/golang.org/x/tools/go/analysis/internal/facts/facts.go 0 → 100644
View file @ 8b469209
// Copyright 2018 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
// Package facts defines a serializable set of analysis.Fact.
//
// It provides a partial implementation of the Fact-related parts of the
// analysis.Pass interface for use in analysis drivers such as "go vet"
// and other build systems.
//
// The serial format is unspecified and may change, so the same version
// of this package must be used for reading and writing serialized facts.
//
// The handling of facts in the analysis system parallels the handling
// of type information in the compiler: during compilation of package P,
// the compiler emits an export data file that describes the type of
// every object (named thing) defined in package P, plus every object
// indirectly reachable from one of those objects. Thus the downstream
// compiler of package Q need only load one export data file per direct
// import of Q, and it will learn everything about the API of package P
// and everything it needs to know about the API of P's dependencies.
//
// Similarly, analysis of package P emits a fact set containing facts
// about all objects exported from P, plus additional facts about only
// those objects of P's dependencies that are reachable from the API of
// package P; the downstream analysis of Q need only load one fact set
// per direct import of Q.
//
// The notion of "exportedness" that matters here is that of the
// compiler. According to the language spec, a method pkg.T.f is
// unexported simply because its name starts with lowercase. But the
// compiler must nonethless export f so that downstream compilations can
// accurately ascertain whether pkg.T implements an interface pkg.I
// defined as interface{f()}. Exported thus means "described in export
// data".
//
package facts
import (
"bytes"
"encoding/gob"
"fmt"
"go/types"
"io/ioutil"
"log"
"reflect"
"sort"
"sync"
"golang.org/x/tools/go/analysis"
"golang.org/x/tools/go/types/objectpath"
)
const debug = false
// A Set is a set of analysis.Facts.
//
// Decode creates a Set of facts by reading from the imports of a given
// package, and Encode writes out the set. Between these operation,
// the Import and Export methods will query and update the set.
//
// All of Set's methods except String are safe to call concurrently.
type Set struct {
pkg *types.Package
mu sync.Mutex
m map[key]analysis.Fact
}
type key struct {
pkg *types.Package
obj types.Object // (object facts only)
t reflect.Type
}
// ImportObjectFact implements analysis.Pass.ImportObjectFact.
func (s *Set) ImportObjectFact(obj types.Object, ptr analysis.Fact) bool {
if obj == nil {
panic("nil object")
}
key := key{pkg: obj.Pkg(), obj: obj, t: reflect.TypeOf(ptr)}
s.mu.Lock()
defer s.mu.Unlock()
if v, ok := s.m[key]; ok {
reflect.ValueOf(ptr).Elem().Set(reflect.ValueOf(v).Elem())
return true
}
return false
}
// ExportObjectFact implements analysis.Pass.ExportObjectFact.
func (s *Set) ExportObjectFact(obj types.Object, fact analysis.Fact) {
if obj.Pkg() != s.pkg {
log.Panicf("in package %s: ExportObjectFact(%s, %T): can't set fact on object belonging another package",
s.pkg, obj, fact)
}
key := key{pkg: obj.Pkg(), obj: obj, t: reflect.TypeOf(fact)}
s.mu.Lock()
s.m[key] = fact // clobber any existing entry
s.mu.Unlock()
}
// ImportPackageFact implements analysis.Pass.ImportPackageFact.
func (s *Set) ImportPackageFact(pkg *types.Package, ptr analysis.Fact) bool {
if pkg == nil {
panic("nil package")
}
key := key{pkg: pkg, t: reflect.TypeOf(ptr)}
s.mu.Lock()
defer s.mu.Unlock()
if v, ok := s.m[key]; ok {
reflect.ValueOf(ptr).Elem().Set(reflect.ValueOf(v).Elem())
return true
}
return false
}
// ExportPackageFact implements analysis.Pass.ExportPackageFact.
func (s *Set) ExportPackageFact(fact analysis.Fact) {
key := key{pkg: s.pkg, t: reflect.TypeOf(fact)}
s.mu.Lock()
s.m[key] = fact // clobber any existing entry
s.mu.Unlock()
}
// gobFact is the Gob declaration of a serialized fact.
type gobFact struct {
PkgPath string // path of package
Object objectpath.Path // optional path of object relative to package itself
Fact analysis.Fact // type and value of user-defined Fact
}
// Decode decodes all the facts relevant to the analysis of package pkg.
// The read function reads serialized fact data from an external source
// for one of of pkg's direct imports. The empty file is a valid
// encoding of an empty fact set.
//
// It is the caller's responsibility to call gob.Register on all
// necessary fact types.
func Decode(pkg *types.Package, read func(packagePath string) ([]byte, error)) (*Set, error) {
// Compute the import map for this package.
// See the package doc comment.
packages := importMap(pkg.Imports())
// Read facts from imported packages.
// Facts may describe indirectly imported packages, or their objects.
m := make(map[key]analysis.Fact) // one big bucket
for _, imp := range pkg.Imports() {
logf := func(format string, args ...interface{}) {
if debug {
prefix := fmt.Sprintf("in %s, importing %s: ",
pkg.Path(), imp.Path())
log.Print(prefix, fmt.Sprintf(format, args...))
}
}
// Read the gob-encoded facts.
data, err := read(imp.Path())
if err != nil {
return nil, fmt.Errorf("in %s, can't import facts for package %q: %v",
pkg.Path(), imp.Path(), err)
}
if len(data) == 0 {
continue // no facts
}
var gobFacts []gobFact
if err := gob.NewDecoder(bytes.NewReader(data)).Decode(&gobFacts); err != nil {
return nil, fmt.Errorf("decoding facts for %q: %v", imp.Path(), err)
}
if debug {
logf("decoded %d facts: %v", len(gobFacts), gobFacts)
}
// Parse each one into a key and a Fact.
for _, f := range gobFacts {
factPkg := packages[f.PkgPath]
if factPkg == nil {
// Fact relates to a dependency that was
// unused in this translation unit. Skip.
logf("no package %q; discarding %v", f.PkgPath, f.Fact)
continue
}
key := key{pkg: factPkg, t: reflect.TypeOf(f.Fact)}
if f.Object != "" {
// object fact
obj, err := objectpath.Object(factPkg, f.Object)
if err != nil {
// (most likely due to unexported object)
// TODO(adonovan): audit for other possibilities.
logf("no object for path: %v; discarding %s", err, f.Fact)
continue
}
key.obj = obj
logf("read %T fact %s for %v", f.Fact, f.Fact, key.obj)
} else {
// package fact
logf("read %T fact %s for %v", f.Fact, f.Fact, factPkg)
}
m[key] = f.Fact
}
}
return &Set{pkg: pkg, m: m}, nil
}
// Encode encodes a set of facts to a memory buffer.
//
// It may fail if one of the Facts could not be gob-encoded, but this is
// a sign of a bug in an Analyzer.
func (s *Set) Encode() []byte {
// TODO(adonovan): opt: use a more efficient encoding
// that avoids repeating PkgPath for each fact.
// Gather all facts, including those from imported packages.
var gobFacts []gobFact
s.mu.Lock()
for k, fact := range s.m {
if debug {
log.Printf("%v => %s\n", k, fact)
}
var object objectpath.Path
if k.obj != nil {
path, err := objectpath.For(k.obj)
if err != nil {
if debug {
log.Printf("discarding fact %s about %s\n", fact, k.obj)
}
continue // object not accessible from package API; discard fact
}
object = path
}
gobFacts = append(gobFacts, gobFact{
PkgPath: k.pkg.Path(),
Object: object,
Fact: fact,
})
}
s.mu.Unlock()
// Sort facts by (package, object, type) for determinism.
sort.Slice(gobFacts, func(i, j int) bool {
x, y := gobFacts[i], gobFacts[j]
if x.PkgPath != y.PkgPath {
return x.PkgPath < y.PkgPath
}
if x.Object != y.Object {
return x.Object < y.Object
}
tx := reflect.TypeOf(x.Fact)
ty := reflect.TypeOf(y.Fact)
if tx != ty {
return tx.String() < ty.String()
}
return false // equal
})
var buf bytes.Buffer
if len(gobFacts) > 0 {
if err := gob.NewEncoder(&buf).Encode(gobFacts); err != nil {
// Fact encoding should never fail. Identify the culprit.
for _, gf := range gobFacts {
if err := gob.NewEncoder(ioutil.Discard).Encode(gf); err != nil {
fact := gf.Fact
pkgpath := reflect.TypeOf(fact).Elem().PkgPath()
log.Panicf("internal error: gob encoding of analysis fact %s failed: %v; please report a bug against fact %T in package %q",
fact, err, fact, pkgpath)
}
}
}
}
if debug {
log.Printf("package %q: encode %d facts, %d bytes\n",
s.pkg.Path(), len(gobFacts), buf.Len())
}
return buf.Bytes()
}
// String is provided only for debugging, and must not be called
// concurrent with any Import/Export method.
func (s *Set) String() string {
var buf bytes.Buffer
buf.WriteString("{")
for k, f := range s.m {
if buf.Len() > 1 {
buf.WriteString(", ")
}
if k.obj != nil {
buf.WriteString(k.obj.String())
} else {
buf.WriteString(k.pkg.Path())
}
fmt.Fprintf(&buf, ": %v", f)
}
buf.WriteString("}")
return buf.String()
}
src/cmd/vendor/golang.org/x/tools/go/analysis/internal/facts/imports.go 0 → 100644
View file @ 8b469209
// Copyright 2018 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
package facts
import "go/types"
// importMap computes the import map for a package by traversing the
// entire exported API each of its imports.
//
// This is a workaround for the fact that we cannot access the map used
// internally by the types.Importer returned by go/importer. The entries
// in this map are the packages and objects that may be relevant to the
// current analysis unit.
//
// Packages in the map that are only indirectly imported may be
// incomplete (!pkg.Complete()).
//
func importMap(imports []*types.Package) map[string]*types.Package {
objects := make(map[types.Object]bool)
packages := make(map[string]*types.Package)
var addObj func(obj types.Object) bool
var addType func(T types.Type)
addObj = func(obj types.Object) bool {
if !objects[obj] {
objects[obj] = true
addType(obj.Type())
if pkg := obj.Pkg(); pkg != nil {
packages[pkg.Path()] = pkg
}
return true
}
return false
}
addType = func(T types.Type) {
switch T := T.(type) {
case *types.Basic:
// nop
case *types.Named:
if addObj(T.Obj()) {
for i := 0; i < T.NumMethods(); i++ {
addObj(T.Method(i))
}
}
case *types.Pointer:
addType(T.Elem())
case *types.Slice:
addType(T.Elem())
case *types.Array:
addType(T.Elem())
case *types.Chan:
addType(T.Elem())
case *types.Map:
addType(T.Key())
addType(T.Elem())
case *types.Signature:
addType(T.Params())
addType(T.Results())
case *types.Struct:
for i := 0; i < T.NumFields(); i++ {
addObj(T.Field(i))
}
case *types.Tuple:
for i := 0; i < T.Len(); i++ {
addObj(T.At(i))
}
case *types.Interface:
for i := 0; i < T.NumMethods(); i++ {
addObj(T.Method(i))
}
}
}
for _, imp := range imports {
packages[imp.Path()] = imp
scope := imp.Scope()
for _, name := range scope.Names() {
addObj(scope.Lookup(name))
}
}
return packages
}
src/cmd/vendor/golang.org/x/tools/go/analysis/internal/unitchecker/unitchecker.go 0 → 100644
View file @ 8b469209
// Copyright 2018 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
// The unitchecker package defines the main function for an analysis
// driver that analyzes a single compilation unit during a build.
// It is invoked by a build system such as "go vet":
//
// $ GOVETTOOL=$(which vet) go vet
//
// It supports the following command-line protocol:
//
// -V=full describe executable (to the build tool)
// -flags describe flags (to the build tool)
// foo.cfg description of compilation unit (from the build tool)
//
// This package does not depend on go/packages.
// If you need a standalone tool, use multichecker,
// which supports this mode but can also load packages
// from source using go/packages.
package unitchecker
// TODO(adonovan):
// - with gccgo, go build does not build standard library,
// so we will not get to analyze it. Yet we must in order
// to create base facts for, say, the fmt package for the
// printf checker.
// - support JSON output, factored with multichecker.
import (
"encoding/gob"
"encoding/json"
"fmt"
"go/ast"
"go/build"
"go/importer"
"go/parser"
"go/token"
"go/types"
"io"
"io/ioutil"
"log"
"os"
"sort"
"strings"
"sync"
"time"
"golang.org/x/tools/go/analysis"
"golang.org/x/tools/go/analysis/internal/facts"
)
// A Config describes a compilation unit to be analyzed.
// It is provided to the tool in a JSON-encoded file
// whose name ends with ".cfg".
type Config struct {
Compiler string
Dir string
ImportPath string
GoFiles []string
OtherFiles []string // TODO(adonovan): make go vet populate this (github.com/golang/go/issues/27665)
ImportMap map[string]string
PackageFile map[string]string
Standard map[string]bool
PackageVetx map[string]string
VetxOnly bool
VetxOutput string
SucceedOnTypecheckFailure bool
}
// Main reads the *.cfg file, runs the analysis,
// and calls os.Exit with an appropriate error code.
func Main(configFile string, analyzers []*analysis.Analyzer) {
cfg, err := readConfig(configFile)
if err != nil {
log.Fatal(err)
}
fset := token.NewFileSet()
diags, err := run(fset, cfg, analyzers)
if err != nil {
log.Fatal(err)
}
if len(diags) > 0 {
for _, diag := range diags {
fmt.Fprintf(os.Stderr, "%s: %s\n", fset.Position(diag.Pos), diag.Message)
}
os.Exit(1)
}
os.Exit(0)
}
func readConfig(filename string) (*Config, error) {
data, err := ioutil.ReadFile(filename)
if err != nil {
return nil, err
}
cfg := new(Config)
if err := json.Unmarshal(data, cfg); err != nil {
return nil, fmt.Errorf("cannot decode JSON config file %s: %v", filename, err)
}
if len(cfg.GoFiles) == 0 {
// The go command disallows packages with no files.
// The only exception is unsafe, but the go command
// doesn't call vet on it.
return nil, fmt.Errorf("package has no files: %s", cfg.ImportPath)
}
return cfg, nil
}
func run(fset *token.FileSet, cfg *Config, analyzers []*analysis.Analyzer) ([]analysis.Diagnostic, error) {
// Load, parse, typecheck.
var files []*ast.File
for _, name := range cfg.GoFiles {
f, err := parser.ParseFile(fset, name, nil, parser.ParseComments)
if err != nil {
if cfg.SucceedOnTypecheckFailure {
// Silently succeed; let the compiler
// report parse errors.
err = nil
}
return nil, err
}
files = append(files, f)
}
compilerImporter := importer.For(cfg.Compiler, func(path string) (io.ReadCloser, error) {
// path is a resolved package path, not an import path.
file, ok := cfg.PackageFile[path]
if !ok {
if cfg.Compiler == "gccgo" && cfg.Standard[path] {
return nil, nil // fall back to default gccgo lookup
}
return nil, fmt.Errorf("no package file for %q", path)
}
return os.Open(file)
})
importer := importerFunc(func(importPath string) (*types.Package, error) {
path, ok := cfg.ImportMap[importPath] // resolve vendoring, etc
if !ok {
return nil, fmt.Errorf("can't resolve import %q", path)
}
return compilerImporter.Import(path)
})
tc := &types.Config{
Importer: importer,
Sizes: types.SizesFor("gc", build.Default.GOARCH), // assume gccgo ≡ gc?
}
info := &types.Info{
Types: make(map[ast.Expr]types.TypeAndValue),
Defs: make(map[*ast.Ident]types.Object),
Uses: make(map[*ast.Ident]types.Object),
Implicits: make(map[ast.Node]types.Object),
Scopes: make(map[ast.Node]*types.Scope),
Selections: make(map[*ast.SelectorExpr]*types.Selection),
}
pkg, err := tc.Check(cfg.ImportPath, fset, files, info)
if err != nil {
if cfg.SucceedOnTypecheckFailure {
// Silently succeed; let the compiler
// report type errors.
err = nil
}
return nil, err
}
// Register fact types with gob.
// In VetxOnly mode, analyzers are only for their facts,
// so we can skip any analysis that neither produces facts
// nor depends on any analysis that produces facts.
// Also build a map to hold working state and result.
type action struct {
once sync.Once
result interface{}
err error
usesFacts bool // (transitively uses)
diagnostics []analysis.Diagnostic
}
actions := make(map[*analysis.Analyzer]*action)
var registerFacts func(a *analysis.Analyzer) bool
registerFacts = func(a *analysis.Analyzer) bool {
act, ok := actions[a]
if !ok {
act = new(action)
var usesFacts bool
for _, f := range a.FactTypes {
usesFacts = true
gob.Register(f)
}
for _, req := range a.Requires {
if registerFacts(req) {
usesFacts = true
}
}
act.usesFacts = usesFacts
actions[a] = act
}
return act.usesFacts
}
var filtered []*analysis.Analyzer
for _, a := range analyzers {
if registerFacts(a) || !cfg.VetxOnly {
filtered = append(filtered, a)
}
}
analyzers = filtered
// Read facts from imported packages.
read := func(path string) ([]byte, error) {
if vetx, ok := cfg.PackageVetx[path]; ok {
return ioutil.ReadFile(vetx)
}
return nil, nil // no .vetx file, no facts
}
facts, err := facts.Decode(pkg, read)
if err != nil {
return nil, err
}
// In parallel, execute the DAG of analyzers.
var exec func(a *analysis.Analyzer) *action
var execAll func(analyzers []*analysis.Analyzer)
exec = func(a *analysis.Analyzer) *action {
act := actions[a]
act.once.Do(func() {
execAll(a.Requires) // prefetch dependencies in parallel
// The inputs to this analysis are the
// results of its prerequisites.
inputs := make(map[*analysis.Analyzer]interface{})
var failed []string
for _, req := range a.Requires {
reqact := exec(req)
if reqact.err != nil {
failed = append(failed, req.String())
continue
}
inputs[req] = reqact.result
}
// Report an error if any dependency failed.
if failed != nil {
sort.Strings(failed)
act.err = fmt.Errorf("failed prerequisites: %s", strings.Join(failed, ", "))
return
}
pass := &analysis.Pass{
Analyzer: a,
Fset: fset,
Files: files,
OtherFiles: cfg.OtherFiles,
Pkg: pkg,
TypesInfo: info,
ResultOf: inputs,
Report: func(d analysis.Diagnostic) { act.diagnostics = append(act.diagnostics, d) },
ImportObjectFact: facts.ImportObjectFact,
ExportObjectFact: facts.ExportObjectFact,
ImportPackageFact: facts.ImportPackageFact,
ExportPackageFact: facts.ExportPackageFact,
}
t0 := time.Now()
act.result, act.err = a.Run(pass)
if false {
log.Printf("analysis %s = %s", pass, time.Since(t0))
}
})
return act
}
execAll = func(analyzers []*analysis.Analyzer) {
var wg sync.WaitGroup
for _, a := range analyzers {
wg.Add(1)
go func(a *analysis.Analyzer) {
_ = exec(a)
wg.Done()
}(a)
}
wg.Wait()
}
execAll(analyzers)
// Return diagnostics from root analyzers.
var diags []analysis.Diagnostic
for _, a := range analyzers {
act := actions[a]
if act.err != nil {
return nil, act.err // some analysis failed
}
diags = append(diags, act.diagnostics...)
}
data := facts.Encode()
if err := ioutil.WriteFile(cfg.VetxOutput, data, 0666); err != nil {
return nil, fmt.Errorf("failed to write analysis facts: %v", err)
}
return diags, nil
}
type importerFunc func(path string) (*types.Package, error)
func (f importerFunc) Import(path string) (*types.Package, error) { return f(path) }
src/cmd/vendor/golang.org/x/tools/go/analysis/passes/asmdecl/asmdecl.go 0 → 100644
View file @ 8b469209
// Copyright 2013 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
// Package asmdecl defines an Analyzer that reports mismatches between
// assembly files and Go declarations.
package asmdecl
import (
"bytes"
"fmt"
"go/ast"
"go/build"
"go/token"
"go/types"
"log"
"regexp"
"strconv"
"strings"
"golang.org/x/tools/go/analysis"
"golang.org/x/tools/go/analysis/passes/internal/analysisutil"
)
var Analyzer = &analysis.Analyzer{
Name: "asmdecl",
Doc: "report mismatches between assembly files and Go declarations",
Run: run,
}
// 'kind' is a kind of assembly variable.
// The kinds 1, 2, 4, 8 stand for values of that size.
type asmKind int
// These special kinds are not valid sizes.
const (
asmString asmKind = 100 + iota
asmSlice
asmArray
asmInterface
asmEmptyInterface
asmStruct
asmComplex
)
// An asmArch describes assembly parameters for an architecture
type asmArch struct {
name string
bigEndian bool
stack string
lr bool
// calculated during initialization
sizes types.Sizes
intSize int
ptrSize int
maxAlign int
}
// An asmFunc describes the expected variables for a function on a given architecture.
type asmFunc struct {
arch *asmArch
size int // size of all arguments
vars map[string]*asmVar
varByOffset map[int]*asmVar
}
// An asmVar describes a single assembly variable.
type asmVar struct {
name string
kind asmKind
typ string
off int
size int
inner []*asmVar
}
var (
asmArch386 = asmArch{name: "386", bigEndian: false, stack: "SP", lr: false}
asmArchArm = asmArch{name: "arm", bigEndian: false, stack: "R13", lr: true}
asmArchArm64 = asmArch{name: "arm64", bigEndian: false, stack: "RSP", lr: true}
asmArchAmd64 = asmArch{name: "amd64", bigEndian: false, stack: "SP", lr: false}
asmArchAmd64p32 = asmArch{name: "amd64p32", bigEndian: false, stack: "SP", lr: false}
asmArchMips = asmArch{name: "mips", bigEndian: true, stack: "R29", lr: true}
asmArchMipsLE = asmArch{name: "mipsle", bigEndian: false, stack: "R29", lr: true}
asmArchMips64 = asmArch{name: "mips64", bigEndian: true, stack: "R29", lr: true}
asmArchMips64LE = asmArch{name: "mips64le", bigEndian: false, stack: "R29", lr: true}
asmArchPpc64 = asmArch{name: "ppc64", bigEndian: true, stack: "R1", lr: true}
asmArchPpc64LE = asmArch{name: "ppc64le", bigEndian: false, stack: "R1", lr: true}
asmArchS390X = asmArch{name: "s390x", bigEndian: true, stack: "R15", lr: true}
asmArchWasm = asmArch{name: "wasm", bigEndian: false, stack: "SP", lr: false}
arches = []*asmArch{
&asmArch386,
&asmArchArm,
&asmArchArm64,
&asmArchAmd64,
&asmArchAmd64p32,
&asmArchMips,
&asmArchMipsLE,
&asmArchMips64,
&asmArchMips64LE,
&asmArchPpc64,
&asmArchPpc64LE,
&asmArchS390X,
&asmArchWasm,
}
)
func init() {
for _, arch := range arches {
arch.sizes = types.SizesFor("gc", arch.name)
if arch.sizes == nil {
// TODO(adonovan): fix: now that asmdecl is not in the standard
// library we cannot assume types.SizesFor is consistent with arches.
// For now, assume 64-bit norms and print a warning.
// But this warning should really be deferred until we attempt to use
// arch, which is very unlikely.
arch.sizes = types.SizesFor("gc", "amd64")
log.Printf("unknown architecture %s", arch.name)
}
arch.intSize = int(arch.sizes.Sizeof(types.Typ[types.Int]))
arch.ptrSize = int(arch.sizes.Sizeof(types.Typ[types.UnsafePointer]))
arch.maxAlign = int(arch.sizes.Alignof(types.Typ[types.Int64]))
}
}
var (
re = regexp.MustCompile
asmPlusBuild = re(`//\s+\+build\s+([^\n]+)`)
asmTEXT = re(`\bTEXT\b(.*)·([^\(]+)\(SB\)(?:\s*,\s*([0-9A-Z|+()]+))?(?:\s*,\s*\$(-?[0-9]+)(?:-([0-9]+))?)?`)
asmDATA = re(`\b(DATA|GLOBL)\b`)
asmNamedFP = re(`([a-zA-Z0-9_\xFF-\x{10FFFF}]+)(?:\+([0-9]+))\(FP\)`)
asmUnnamedFP = re(`[^+\-0-9](([0-9]+)\(FP\))`)
asmSP = re(`[^+\-0-9](([0-9]+)\(([A-Z0-9]+)\))`)
asmOpcode = re(`^\s*(?:[A-Z0-9a-z_]+:)?\s*([A-Z]+)\s*([^,]*)(?:,\s*(.*))?`)
ppc64Suff = re(`([BHWD])(ZU|Z|U|BR)?$`)
)
func run(pass *analysis.Pass) (interface{}, error) {
// No work if no assembly files.
var sfiles []string
for _, fname := range pass.OtherFiles {
if strings.HasSuffix(fname, ".s") {
sfiles = append(sfiles, fname)
}
}
if sfiles == nil {
return nil, nil
}
// Gather declarations. knownFunc[name][arch] is func description.
knownFunc := make(map[string]map[string]*asmFunc)
for _, f := range pass.Files {
for _, decl := range f.Decls {
if decl, ok := decl.(*ast.FuncDecl); ok && decl.Body == nil {
knownFunc[decl.Name.Name] = asmParseDecl(pass, decl)
}
}
}
Files:
for _, fname := range sfiles {
content, tf, err := analysisutil.ReadFile(pass.Fset, fname)
if err != nil {
return nil, err
}
// Determine architecture from file name if possible.
var arch string
var archDef *asmArch
for _, a := range arches {
if strings.HasSuffix(fname, "_"+a.name+".s") {
arch = a.name
archDef = a
break
}
}
lines := strings.SplitAfter(string(content), "\n")
var (
fn *asmFunc
fnName string
localSize, argSize int
wroteSP bool
haveRetArg bool
retLine []int
)
flushRet := func() {
if fn != nil && fn.vars["ret"] != nil && !haveRetArg && len(retLine) > 0 {
v := fn.vars["ret"]
for _, line := range retLine {
pass.Reportf(analysisutil.LineStart(tf, line), "[%s] %s: RET without writing to %d-byte ret+%d(FP)", arch, fnName, v.size, v.off)
}
}
retLine = nil
}
for lineno, line := range lines {
lineno++
badf := func(format string, args ...interface{}) {
pass.Reportf(analysisutil.LineStart(tf, lineno), "[%s] %s: %s", arch, fnName, fmt.Sprintf(format, args...))
}
if arch == "" {
// Determine architecture from +build line if possible.
if m := asmPlusBuild.FindStringSubmatch(line); m != nil {
// There can be multiple architectures in a single +build line,
// so accumulate them all and then prefer the one that
// matches build.Default.GOARCH.
var archCandidates []*asmArch
for _, fld := range strings.Fields(m[1]) {
for _, a := range arches {
if a.name == fld {
archCandidates = append(archCandidates, a)
}
}
}
for _, a := range archCandidates {
if a.name == build.Default.GOARCH {
archCandidates = []*asmArch{a}
break
}
}
if len(archCandidates) > 0 {
arch = archCandidates[0].name
archDef = archCandidates[0]
}
}
}
if m := asmTEXT.FindStringSubmatch(line); m != nil {
flushRet()
if arch == "" {
// Arch not specified by filename or build tags.
// Fall back to build.Default.GOARCH.
for _, a := range arches {
if a.name == build.Default.GOARCH {
arch = a.name
archDef = a
break
}
}
if arch == "" {
badf("%s: cannot determine architecture for assembly file")
continue Files
}
}
fnName = m[2]
if pkgName := strings.TrimSpace(m[1]); pkgName != "" {
pathParts := strings.Split(pkgName, "∕")
pkgName = pathParts[len(pathParts)-1]
if pkgName != pass.Pkg.Path() {
badf("[%s] cannot check cross-package assembly function: %s is in package %s", arch, fnName, pkgName)
fn = nil
fnName = ""
continue
}
}
flag := m[3]
fn = knownFunc[fnName][arch]
if fn != nil {
size, _ := strconv.Atoi(m[5])
if size != fn.size && (flag != "7" && !strings.Contains(flag, "NOSPLIT") || size != 0) {
badf("wrong argument size %d; expected $...-%d", size, fn.size)
}
}
localSize, _ = strconv.Atoi(m[4])
localSize += archDef.intSize
if archDef.lr && !strings.Contains(flag, "NOFRAME") {
// Account for caller's saved LR
localSize += archDef.intSize
}
argSize, _ = strconv.Atoi(m[5])
if fn == nil && !strings.Contains(fnName, "<>") {
badf("function %s missing Go declaration", fnName)
}
wroteSP = false
haveRetArg = false
continue
} else if strings.Contains(line, "TEXT") && strings.Contains(line, "SB") {
// function, but not visible from Go (didn't match asmTEXT), so stop checking
flushRet()
fn = nil
fnName = ""
continue
}
if strings.Contains(line, "RET") {
retLine = append(retLine, lineno)
}
if fnName == "" {
continue
}
if asmDATA.FindStringSubmatch(line) != nil {
fn = nil
}
if archDef == nil {
continue
}
if strings.Contains(line, ", "+archDef.stack) || strings.Contains(line, ",\t"+archDef.stack) {
wroteSP = true
continue
}
for _, m := range asmSP.FindAllStringSubmatch(line, -1) {
if m[3] != archDef.stack || wroteSP {
continue
}
off := 0
if m[1] != "" {
off, _ = strconv.Atoi(m[2])
}
if off >= localSize {
if fn != nil {
v := fn.varByOffset[off-localSize]
if v != nil {
badf("%s should be %s+%d(FP)", m[1], v.name, off-localSize)
continue
}
}
if off >= localSize+argSize {
badf("use of %s points beyond argument frame", m[1])
continue
}
badf("use of %s to access argument frame", m[1])
}
}
if fn == nil {
continue
}
for _, m := range asmUnnamedFP.FindAllStringSubmatch(line, -1) {
off, _ := strconv.Atoi(m[2])
v := fn.varByOffset[off]
if v != nil {
badf("use of unnamed argument %s; offset %d is %s+%d(FP)", m[1], off, v.name, v.off)
} else {
badf("use of unnamed argument %s", m[1])
}
}
for _, m := range asmNamedFP.FindAllStringSubmatch(line, -1) {
name := m[1]
off := 0
if m[2] != "" {
off, _ = strconv.Atoi(m[2])
}
if name == "ret" || strings.HasPrefix(name, "ret_") {
haveRetArg = true
}
v := fn.vars[name]
if v == nil {
// Allow argframe+0(FP).
if name == "argframe" && off == 0 {
continue
}
v = fn.varByOffset[off]
if v != nil {
badf("unknown variable %s; offset %d is %s+%d(FP)", name, off, v.name, v.off)
} else {
badf("unknown variable %s", name)
}
continue
}
asmCheckVar(badf, fn, line, m[0], off, v)
}
}
flushRet()
}
return nil, nil
}
func asmKindForType(t types.Type, size int) asmKind {
switch t := t.Underlying().(type) {
case *types.Basic:
switch t.Kind() {
case types.String:
return asmString
case types.Complex64, types.Complex128:
return asmComplex
}
return asmKind(size)
case *types.Pointer, *types.Chan, *types.Map, *types.Signature:
return asmKind(size)
case *types.Struct:
return asmStruct
case *types.Interface:
if t.Empty() {
return asmEmptyInterface
}
return asmInterface
case *types.Array:
return asmArray
case *types.Slice:
return asmSlice
}
panic("unreachable")
}
// A component is an assembly-addressable component of a composite type,
// or a composite type itself.
type component struct {
size int
offset int
kind asmKind
typ string
suffix string // Such as _base for string base, _0_lo for lo half of first element of [1]uint64 on 32 bit machine.
outer string // The suffix for immediately containing composite type.
}
func newComponent(suffix string, kind asmKind, typ string, offset, size int, outer string) component {
return component{suffix: suffix, kind: kind, typ: typ, offset: offset, size: size, outer: outer}
}
// componentsOfType generates a list of components of type t.
// For example, given string, the components are the string itself, the base, and the length.
func componentsOfType(arch *asmArch, t types.Type) []component {
return appendComponentsRecursive(arch, t, nil, "", 0)
}
// appendComponentsRecursive implements componentsOfType.
// Recursion is required to correct handle structs and arrays,
// which can contain arbitrary other types.
func appendComponentsRecursive(arch *asmArch, t types.Type, cc []component, suffix string, off int) []component {
s := t.String()
size := int(arch.sizes.Sizeof(t))
kind := asmKindForType(t, size)
cc = append(cc, newComponent(suffix, kind, s, off, size, suffix))
switch kind {
case 8:
if arch.ptrSize == 4 {
w1, w2 := "lo", "hi"
if arch.bigEndian {
w1, w2 = w2, w1
}
cc = append(cc, newComponent(suffix+"_"+w1, 4, "half "+s, off, 4, suffix))
cc = append(cc, newComponent(suffix+"_"+w2, 4, "half "+s, off+4, 4, suffix))
}
case asmEmptyInterface:
cc = append(cc, newComponent(suffix+"_type", asmKind(arch.ptrSize), "interface type", off, arch.ptrSize, suffix))
cc = append(cc, newComponent(suffix+"_data", asmKind(arch.ptrSize), "interface data", off+arch.ptrSize, arch.ptrSize, suffix))
case asmInterface:
cc = append(cc, newComponent(suffix+"_itable", asmKind(arch.ptrSize), "interface itable", off, arch.ptrSize, suffix))
cc = append(cc, newComponent(suffix+"_data", asmKind(arch.ptrSize), "interface data", off+arch.ptrSize, arch.ptrSize, suffix))
case asmSlice:
cc = append(cc, newComponent(suffix+"_base", asmKind(arch.ptrSize), "slice base", off, arch.ptrSize, suffix))
cc = append(cc, newComponent(suffix+"_len", asmKind(arch.intSize), "slice len", off+arch.ptrSize, arch.intSize, suffix))
cc = append(cc, newComponent(suffix+"_cap", asmKind(arch.intSize), "slice cap", off+arch.ptrSize+arch.intSize, arch.intSize, suffix))
case asmString:
cc = append(cc, newComponent(suffix+"_base", asmKind(arch.ptrSize), "string base", off, arch.ptrSize, suffix))
cc = append(cc, newComponent(suffix+"_len", asmKind(arch.intSize), "string len", off+arch.ptrSize, arch.intSize, suffix))
case asmComplex:
fsize := size / 2
cc = append(cc, newComponent(suffix+"_real", asmKind(fsize), fmt.Sprintf("real(complex%d)", size*8), off, fsize, suffix))
cc = append(cc, newComponent(suffix+"_imag", asmKind(fsize), fmt.Sprintf("imag(complex%d)", size*8), off+fsize, fsize, suffix))
case asmStruct:
tu := t.Underlying().(*types.Struct)
fields := make([]*types.Var, tu.NumFields())
for i := 0; i < tu.NumFields(); i++ {
fields[i] = tu.Field(i)
}
offsets := arch.sizes.Offsetsof(fields)
for i, f := range fields {
cc = appendComponentsRecursive(arch, f.Type(), cc, suffix+"_"+f.Name(), off+int(offsets[i]))
}
case asmArray:
tu := t.Underlying().(*types.Array)
elem := tu.Elem()
// Calculate offset of each element array.
fields := []*types.Var{
types.NewVar(token.NoPos, nil, "fake0", elem),
types.NewVar(token.NoPos, nil, "fake1", elem),
}
offsets := arch.sizes.Offsetsof(fields)
elemoff := int(offsets[1])
for i := 0; i < int(tu.Len()); i++ {
cc = appendComponentsRecursive(arch, elem, cc, suffix+"_"+strconv.Itoa(i), i*elemoff)
}
}
return cc
}
// asmParseDecl parses a function decl for expected assembly variables.
func asmParseDecl(pass *analysis.Pass, decl *ast.FuncDecl) map[string]*asmFunc {
var (
arch *asmArch
fn *asmFunc
offset int
)
// addParams adds asmVars for each of the parameters in list.
// isret indicates whether the list are the arguments or the return values.
// TODO(adonovan): simplify by passing (*types.Signature).{Params,Results}
// instead of list.
addParams := func(list []*ast.Field, isret bool) {
argnum := 0
for _, fld := range list {
t := pass.TypesInfo.Types[fld.Type].Type
// Work around github.com/golang/go/issues/28277.
if t == nil {
if ell, ok := fld.Type.(*ast.Ellipsis); ok {
t = types.NewSlice(pass.TypesInfo.Types[ell.Elt].Type)
}
}
align := int(arch.sizes.Alignof(t))
size := int(arch.sizes.Sizeof(t))
offset += -offset & (align - 1)
cc := componentsOfType(arch, t)
// names is the list of names with this type.
names := fld.Names
if len(names) == 0 {
// Anonymous args will be called arg, arg1, arg2, ...
// Similarly so for return values: ret, ret1, ret2, ...
name := "arg"
if isret {
name = "ret"
}
if argnum > 0 {
name += strconv.Itoa(argnum)
}
names = []*ast.Ident{ast.NewIdent(name)}
}
argnum += len(names)
// Create variable for each name.
for _, id := range names {
name := id.Name
for _, c := range cc {
outer := name + c.outer
v := asmVar{
name: name + c.suffix,
kind: c.kind,
typ: c.typ,
off: offset + c.offset,
size: c.size,
}
if vo := fn.vars[outer]; vo != nil {
vo.inner = append(vo.inner, &v)
}
fn.vars[v.name] = &v
for i := 0; i < v.size; i++ {
fn.varByOffset[v.off+i] = &v
}
}
offset += size
}
}
}
m := make(map[string]*asmFunc)
for _, arch = range arches {
fn = &asmFunc{
arch: arch,
vars: make(map[string]*asmVar),
varByOffset: make(map[int]*asmVar),
}
offset = 0
addParams(decl.Type.Params.List, false)
if decl.Type.Results != nil && len(decl.Type.Results.List) > 0 {
offset += -offset & (arch.maxAlign - 1)
addParams(decl.Type.Results.List, true)
}
fn.size = offset
m[arch.name] = fn
}
return m
}
// asmCheckVar checks a single variable reference.
func asmCheckVar(badf func(string, ...interface{}), fn *asmFunc, line, expr string, off int, v *asmVar) {
m := asmOpcode.FindStringSubmatch(line)
if m == nil {
if !strings.HasPrefix(strings.TrimSpace(line), "//") {
badf("cannot find assembly opcode")
}
return
}
// Determine operand sizes from instruction.
// Typically the suffix suffices, but there are exceptions.
var src, dst, kind asmKind
op := m[1]
switch fn.arch.name + "." + op {
case "386.FMOVLP":
src, dst = 8, 4
case "arm.MOVD":
src = 8
case "arm.MOVW":
src = 4
case "arm.MOVH", "arm.MOVHU":
src = 2
case "arm.MOVB", "arm.MOVBU":
src = 1
// LEA* opcodes don't really read the second arg.
// They just take the address of it.
case "386.LEAL":
dst = 4
case "amd64.LEAQ":
dst = 8
case "amd64p32.LEAL":
dst = 4
default:
switch fn.arch.name {
case "386", "amd64":
if strings.HasPrefix(op, "F") && (strings.HasSuffix(op, "D") || strings.HasSuffix(op, "DP")) {
// FMOVDP, FXCHD, etc
src = 8
break
}
if strings.HasPrefix(op, "P") && strings.HasSuffix(op, "RD") {
// PINSRD, PEXTRD, etc
src = 4
break
}
if strings.HasPrefix(op, "F") && (strings.HasSuffix(op, "F") || strings.HasSuffix(op, "FP")) {
// FMOVFP, FXCHF, etc
src = 4
break
}
if strings.HasSuffix(op, "SD") {
// MOVSD, SQRTSD, etc
src = 8
break
}
if strings.HasSuffix(op, "SS") {
// MOVSS, SQRTSS, etc
src = 4
break
}
if strings.HasPrefix(op, "SET") {
// SETEQ, etc
src = 1
break
}
switch op[len(op)-1] {
case 'B':
src = 1
case 'W':
src = 2
case 'L':
src = 4
case 'D', 'Q':
src = 8
}
case "ppc64", "ppc64le":
// Strip standard suffixes to reveal size letter.
m := ppc64Suff.FindStringSubmatch(op)
if m != nil {
switch m[1][0] {
case 'B':
src = 1
case 'H':
src = 2
case 'W':
src = 4
case 'D':
src = 8
}
}
case "mips", "mipsle", "mips64", "mips64le":
switch op {
case "MOVB", "MOVBU":
src = 1
case "MOVH", "MOVHU":
src = 2
case "MOVW", "MOVWU", "MOVF":
src = 4
case "MOVV", "MOVD":
src = 8
}
case "s390x":
switch op {
case "MOVB", "MOVBZ":
src = 1
case "MOVH", "MOVHZ":
src = 2
case "MOVW", "MOVWZ", "FMOVS":
src = 4
case "MOVD", "FMOVD":
src = 8
}
}
}
if dst == 0 {
dst = src
}
// Determine whether the match we're holding
// is the first or second argument.
if strings.Index(line, expr) > strings.Index(line, ",") {
kind = dst
} else {
kind = src
}
vk := v.kind
vs := v.size
vt := v.typ
switch vk {
case asmInterface, asmEmptyInterface, asmString, asmSlice:
// allow reference to first word (pointer)
vk = v.inner[0].kind
vs = v.inner[0].size
vt = v.inner[0].typ
}
if off != v.off {
var inner bytes.Buffer
for i, vi := range v.inner {
if len(v.inner) > 1 {
fmt.Fprintf(&inner, ",")
}
fmt.Fprintf(&inner, " ")
if i == len(v.inner)-1 {
fmt.Fprintf(&inner, "or ")
}
fmt.Fprintf(&inner, "%s+%d(FP)", vi.name, vi.off)
}
badf("invalid offset %s; expected %s+%d(FP)%s", expr, v.name, v.off, inner.String())
return
}
if kind != 0 && kind != vk {
var inner bytes.Buffer
if len(v.inner) > 0 {
fmt.Fprintf(&inner, " containing")
for i, vi := range v.inner {
if i > 0 && len(v.inner) > 2 {
fmt.Fprintf(&inner, ",")
}
fmt.Fprintf(&inner, " ")
if i > 0 && i == len(v.inner)-1 {
fmt.Fprintf(&inner, "and ")
}
fmt.Fprintf(&inner, "%s+%d(FP)", vi.name, vi.off)
}
}
badf("invalid %s of %s; %s is %d-byte value%s", op, expr, vt, vs, inner.String())
}
}
src/cmd/vendor/golang.org/x/tools/go/analysis/passes/assign/assign.go 0 → 100644
View file @ 8b469209
// Copyright 2013 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
// Package assign defines an Analyzer that detects useless assignments.
package assign
// TODO(adonovan): check also for assignments to struct fields inside
// methods that are on T instead of *T.
import (
"go/ast"
"go/token"
"reflect"
"golang.org/x/tools/go/analysis"
"golang.org/x/tools/go/analysis/passes/inspect"
"golang.org/x/tools/go/analysis/passes/internal/analysisutil"
"golang.org/x/tools/go/ast/inspector"
)
const Doc = `check for useless assignments
This checker reports assignments of the form x = x or a[i] = a[i].
These are almost always useless, and even when they aren't they are
usually a mistake.`
var Analyzer = &analysis.Analyzer{
Name: "assign",
Doc: Doc,
Requires: []*analysis.Analyzer{inspect.Analyzer},
Run: run,
}
func run(pass *analysis.Pass) (interface{}, error) {
inspect := pass.ResultOf[inspect.Analyzer].(*inspector.Inspector)
nodeFilter := []ast.Node{
(*ast.AssignStmt)(nil),
}
inspect.Preorder(nodeFilter, func(n ast.Node) {
stmt := n.(*ast.AssignStmt)
if stmt.Tok != token.ASSIGN {
return // ignore :=
}
if len(stmt.Lhs) != len(stmt.Rhs) {
// If LHS and RHS have different cardinality, they can't be the same.
return
}
for i, lhs := range stmt.Lhs {
rhs := stmt.Rhs[i]
if analysisutil.HasSideEffects(pass.TypesInfo, lhs) ||
analysisutil.HasSideEffects(pass.TypesInfo, rhs) {
continue // expressions may not be equal
}
if reflect.TypeOf(lhs) != reflect.TypeOf(rhs) {
continue // short-circuit the heavy-weight gofmt check
}
le := analysisutil.Format(pass.Fset, lhs)
re := analysisutil.Format(pass.Fset, rhs)
if le == re {
pass.Reportf(stmt.Pos(), "self-assignment of %s to %s", re, le)
}
}
})
return nil, nil
}
src/cmd/vendor/golang.org/x/tools/go/analysis/passes/atomic/atomic.go 0 → 100644
View file @ 8b469209
// Copyright 2013 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
// Package atomic defines an Analyzer that checks for common mistakes
// using the sync/atomic package.
package atomic
import (
"go/ast"
"go/token"
"go/types"
"golang.org/x/tools/go/analysis"
"golang.org/x/tools/go/analysis/passes/inspect"
"golang.org/x/tools/go/analysis/passes/internal/analysisutil"
"golang.org/x/tools/go/ast/inspector"
)
const Doc = `check for common mistakes using the sync/atomic package
The atomic checker looks for assignment statements of the form:
x = atomic.AddUint64(&x, 1)
which are not atomic.`
var Analyzer = &analysis.Analyzer{
Name: "atomic",
Doc: Doc,
Requires: []*analysis.Analyzer{inspect.Analyzer},
RunDespiteErrors: true,
Run: run,
}
func run(pass *analysis.Pass) (interface{}, error) {
inspect := pass.ResultOf[inspect.Analyzer].(*inspector.Inspector)
nodeFilter := []ast.Node{
(*ast.AssignStmt)(nil),
}
inspect.Preorder(nodeFilter, func(node ast.Node) {
n := node.(*ast.AssignStmt)
if len(n.Lhs) != len(n.Rhs) {
return
}
if len(n.Lhs) == 1 && n.Tok == token.DEFINE {
return
}
for i, right := range n.Rhs {
call, ok := right.(*ast.CallExpr)
if !ok {
continue
}
sel, ok := call.Fun.(*ast.SelectorExpr)
if !ok {
continue
}
pkgIdent, _ := sel.X.(*ast.Ident)
pkgName, ok := pass.TypesInfo.Uses[pkgIdent].(*types.PkgName)
if !ok || pkgName.Imported().Path() != "sync/atomic" {
continue
}
switch sel.Sel.Name {
case "AddInt32", "AddInt64", "AddUint32", "AddUint64", "AddUintptr":
checkAtomicAddAssignment(pass, n.Lhs[i], call)
}
}
})
return nil, nil
}
// checkAtomicAddAssignment walks the atomic.Add* method calls checking
// for assigning the return value to the same variable being used in the
// operation
func checkAtomicAddAssignment(pass *analysis.Pass, left ast.Expr, call *ast.CallExpr) {
if len(call.Args) != 2 {
return
}
arg := call.Args[0]
broken := false
gofmt := func(e ast.Expr) string { return analysisutil.Format(pass.Fset, e) }
if uarg, ok := arg.(*ast.UnaryExpr); ok && uarg.Op == token.AND {
broken = gofmt(left) == gofmt(uarg.X)
} else if star, ok := left.(*ast.StarExpr); ok {
broken = gofmt(star.X) == gofmt(arg)
}
if broken {
pass.Reportf(left.Pos(), "direct assignment to atomic value")
}
}
src/cmd/vendor/golang.org/x/tools/go/analysis/passes/bools/bools.go 0 → 100644
View file @ 8b469209
// Copyright 2014 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
// Package bools defines an Analyzer that detects common mistakes
// involving boolean operators.
package bools
import (
"go/ast"
"go/token"
"go/types"
"golang.org/x/tools/go/analysis"
"golang.org/x/tools/go/analysis/passes/inspect"
"golang.org/x/tools/go/analysis/passes/internal/analysisutil"
"golang.org/x/tools/go/ast/inspector"
)
var Analyzer = &analysis.Analyzer{
Name: "bools",
Doc: "check for common mistakes involving boolean operators",
Requires: []*analysis.Analyzer{inspect.Analyzer},
Run: run,
}
func run(pass *analysis.Pass) (interface{}, error) {
inspect := pass.ResultOf[inspect.Analyzer].(*inspector.Inspector)
nodeFilter := []ast.Node{
(*ast.BinaryExpr)(nil),
}
inspect.Preorder(nodeFilter, func(n ast.Node) {
e := n.(*ast.BinaryExpr)
var op boolOp
switch e.Op {
case token.LOR:
op = or
case token.LAND:
op = and
default:
return
}
// TODO(adonovan): this reports n(n-1)/2 errors for an
// expression e||...||e of depth n. Fix.
// See https://github.com/golang/go/issues/28086.
comm := op.commutativeSets(pass.TypesInfo, e)
for _, exprs := range comm {
op.checkRedundant(pass, exprs)
op.checkSuspect(pass, exprs)
}
})
return nil, nil
}
type boolOp struct {
name string
tok token.Token // token corresponding to this operator
badEq token.Token // token corresponding to the equality test that should not be used with this operator
}
var (
or = boolOp{"or", token.LOR, token.NEQ}
and = boolOp{"and", token.LAND, token.EQL}
)
// commutativeSets returns all side effect free sets of
// expressions in e that are connected by op.
// For example, given 'a || b || f() || c || d' with the or op,
// commutativeSets returns {{b, a}, {d, c}}.
func (op boolOp) commutativeSets(info *types.Info, e *ast.BinaryExpr) [][]ast.Expr {
exprs := op.split(e)
// Partition the slice of expressions into commutative sets.
i := 0
var sets [][]ast.Expr
for j := 0; j <= len(exprs); j++ {
if j == len(exprs) || hasSideEffects(info, exprs[j]) {
if i < j {
sets = append(sets, exprs[i:j])
}
i = j + 1
}
}
return sets
}
// checkRedundant checks for expressions of the form
// e && e
// e || e
// Exprs must contain only side effect free expressions.
func (op boolOp) checkRedundant(pass *analysis.Pass, exprs []ast.Expr) {
seen := make(map[string]bool)
for _, e := range exprs {
efmt := analysisutil.Format(pass.Fset, e)
if seen[efmt] {
pass.Reportf(e.Pos(), "redundant %s: %s %s %s", op.name, efmt, op.tok, efmt)
} else {
seen[efmt] = true
}
}
}
// checkSuspect checks for expressions of the form
// x != c1 || x != c2
// x == c1 && x == c2
// where c1 and c2 are constant expressions.
// If c1 and c2 are the same then it's redundant;
// if c1 and c2 are different then it's always true or always false.
// Exprs must contain only side effect free expressions.
func (op boolOp) checkSuspect(pass *analysis.Pass, exprs []ast.Expr) {
// seen maps from expressions 'x' to equality expressions 'x != c'.
seen := make(map[string]string)
for _, e := range exprs {
bin, ok := e.(*ast.BinaryExpr)
if !ok || bin.Op != op.badEq {
continue
}
// In order to avoid false positives, restrict to cases
// in which one of the operands is constant. We're then
// interested in the other operand.
// In the rare case in which both operands are constant
// (e.g. runtime.GOOS and "windows"), we'll only catch
// mistakes if the LHS is repeated, which is how most
// code is written.
var x ast.Expr
switch {
case pass.TypesInfo.Types[bin.Y].Value != nil:
x = bin.X
case pass.TypesInfo.Types[bin.X].Value != nil:
x = bin.Y
default:
continue
}
// e is of the form 'x != c' or 'x == c'.
xfmt := analysisutil.Format(pass.Fset, x)
efmt := analysisutil.Format(pass.Fset, e)
if prev, found := seen[xfmt]; found {
// checkRedundant handles the case in which efmt == prev.
if efmt != prev {
pass.Reportf(e.Pos(), "suspect %s: %s %s %s", op.name, efmt, op.tok, prev)
}
} else {
seen[xfmt] = efmt
}
}
}
// hasSideEffects reports whether evaluation of e has side effects.
func hasSideEffects(info *types.Info, e ast.Expr) bool {
safe := true
ast.Inspect(e, func(node ast.Node) bool {
switch n := node.(type) {
case *ast.CallExpr:
typVal := info.Types[n.Fun]
switch {
case typVal.IsType():
// Type conversion, which is safe.
case typVal.IsBuiltin():
// Builtin func, conservatively assumed to not
// be safe for now.
safe = false
return false
default:
// A non-builtin func or method call.
// Conservatively assume that all of them have
// side effects for now.
safe = false
return false
}
case *ast.UnaryExpr:
if n.Op == token.ARROW {
safe = false
return false
}
}
return true
})
return !safe
}
// split returns a slice of all subexpressions in e that are connected by op.
// For example, given 'a || (b || c) || d' with the or op,
// split returns []{d, c, b, a}.
func (op boolOp) split(e ast.Expr) (exprs []ast.Expr) {
for {
e = unparen(e)
if b, ok := e.(*ast.BinaryExpr); ok && b.Op == op.tok {
exprs = append(exprs, op.split(b.Y)...)
e = b.X
} else {
exprs = append(exprs, e)
break
}
}
return
}
// unparen returns e with any enclosing parentheses stripped.
func unparen(e ast.Expr) ast.Expr {
for {
p, ok := e.(*ast.ParenExpr)
if !ok {
return e
}
e = p.X
}
}
src/cmd/vendor/golang.org/x/tools/go/analysis/passes/buildtag/buildtag.go 0 → 100644
View file @ 8b469209
// Copyright 2013 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
// Package buildtag defines an Analyzer that checks build tags.
package buildtag
import (
"bytes"
"fmt"
"go/ast"
"strings"
"unicode"
"golang.org/x/tools/go/analysis"
"golang.org/x/tools/go/analysis/passes/internal/analysisutil"
)
var Analyzer = &analysis.Analyzer{
Name: "buildtag",
Doc: "check that +build tags are well-formed and correctly located",
Run: runBuildTag,
}
func runBuildTag(pass *analysis.Pass) (interface{}, error) {
for _, f := range pass.Files {
checkGoFile(pass, f)
}
for _, name := range pass.OtherFiles {
if err := checkOtherFile(pass, name); err != nil {
return nil, err
}
}
return nil, nil
}
func checkGoFile(pass *analysis.Pass, f *ast.File) {
pastCutoff := false
for _, group := range f.Comments {
// A +build comment is ignored after or adjoining the package declaration.
if group.End()+1 >= f.Package {
pastCutoff = true
}
// "+build" is ignored within or after a /*...*/ comment.
if !strings.HasPrefix(group.List[0].Text, "//") {
pastCutoff = true
continue
}
// Check each line of a //-comment.
for _, c := range group.List {
if !strings.Contains(c.Text, "+build") {
continue
}
if err := checkLine(c.Text, pastCutoff); err != nil {
pass.Reportf(c.Pos(), "%s", err)
}
}
}
}
func checkOtherFile(pass *analysis.Pass, filename string) error {
content, tf, err := analysisutil.ReadFile(pass.Fset, filename)
if err != nil {
return err
}
// We must look at the raw lines, as build tags may appear in non-Go
// files such as assembly files.
lines := bytes.SplitAfter(content, nl)
// Determine cutpoint where +build comments are no longer valid.
// They are valid in leading // comments in the file followed by
// a blank line.
//
// This must be done as a separate pass because of the
// requirement that the comment be followed by a blank line.
var cutoff int
for i, line := range lines {
line = bytes.TrimSpace(line)
if !bytes.HasPrefix(line, slashSlash) {
if len(line) > 0 {
break
}
cutoff = i
}
}
for i, line := range lines {
line = bytes.TrimSpace(line)
if !bytes.HasPrefix(line, slashSlash) {
continue
}
if !bytes.Contains(line, []byte("+build")) {
continue
}
if err := checkLine(string(line), i >= cutoff); err != nil {
pass.Reportf(analysisutil.LineStart(tf, i+1), "%s", err)
continue
}
}
return nil
}
// checkLine checks a line that starts with "//" and contains "+build".
func checkLine(line string, pastCutoff bool) error {
line = strings.TrimPrefix(line, "//")
line = strings.TrimSpace(line)
if strings.HasPrefix(line, "+build") {
fields := strings.Fields(line)
if fields[0] != "+build" {
// Comment is something like +buildasdf not +build.
return fmt.Errorf("possible malformed +build comment")
}
if pastCutoff {
return fmt.Errorf("+build comment must appear before package clause and be followed by a blank line")
}
if err := checkArguments(fields); err != nil {
return err
}
} else {
// Comment with +build but not at beginning.
if !pastCutoff {
return fmt.Errorf("possible malformed +build comment")
}
}
return nil
}
func checkArguments(fields []string) error {
// The original version of this checker in vet could examine
// files with malformed build tags that would cause the file to
// be always ignored by "go build". However, drivers for the new
// analysis API will analyze only the files selected to form a
// package, so these checks will never fire.
// TODO(adonovan): rethink this.
for _, arg := range fields[1:] {
for _, elem := range strings.Split(arg, ",") {
if strings.HasPrefix(elem, "!!") {
return fmt.Errorf("invalid double negative in build constraint: %s", arg)
}
elem = strings.TrimPrefix(elem, "!")
for _, c := range elem {
if !unicode.IsLetter(c) && !unicode.IsDigit(c) && c != '_' && c != '.' {
return fmt.Errorf("invalid non-alphanumeric build constraint: %s", arg)
}
}
}
}
return nil
}
var (
nl = []byte("\n")
slashSlash = []byte("//")
)
src/cmd/vendor/golang.org/x/tools/go/analysis/passes/cgocall/cgocall.go 0 → 100644
View file @ 8b469209
// Copyright 2015 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
// Package cgocall defines an Analyzer that detects some violations of
// the cgo pointer passing rules.
package cgocall
import (
"fmt"
"go/ast"
"go/token"
"go/types"
"log"
"strings"
"golang.org/x/tools/go/analysis"
"golang.org/x/tools/go/analysis/passes/inspect"
"golang.org/x/tools/go/analysis/passes/internal/analysisutil"
"golang.org/x/tools/go/ast/inspector"
)
const Doc = `detect some violations of the cgo pointer passing rules
Check for invalid cgo pointer passing.
This looks for code that uses cgo to call C code passing values
whose types are almost always invalid according to the cgo pointer
sharing rules.
Specifically, it warns about attempts to pass a Go chan, map, func,
or slice to C, either directly, or via a pointer, array, or struct.`
var Analyzer = &analysis.Analyzer{
Name: "cgocall",
Doc: Doc,
Requires: []*analysis.Analyzer{inspect.Analyzer},
RunDespiteErrors: true,
Run: run,
}
func run(pass *analysis.Pass) (interface{}, error) {
inspect := pass.ResultOf[inspect.Analyzer].(*inspector.Inspector)
nodeFilter := []ast.Node{
(*ast.CallExpr)(nil),
}
inspect.WithStack(nodeFilter, func(n ast.Node, push bool, stack []ast.Node) bool {
if !push {
return true
}
call, name := findCall(pass.Fset, stack)
if call == nil {
return true // not a call we need to check
}
// A call to C.CBytes passes a pointer but is always safe.
if name == "CBytes" {
return true
}
if false {
fmt.Printf("%s: inner call to C.%s\n", pass.Fset.Position(n.Pos()), name)
fmt.Printf("%s: outer call to C.%s\n", pass.Fset.Position(call.Lparen), name)
}
for _, arg := range call.Args {
if !typeOKForCgoCall(cgoBaseType(pass.TypesInfo, arg), make(map[types.Type]bool)) {
pass.Reportf(arg.Pos(), "possibly passing Go type with embedded pointer to C")
break
}
// Check for passing the address of a bad type.
if conv, ok := arg.(*ast.CallExpr); ok && len(conv.Args) == 1 &&
isUnsafePointer(pass.TypesInfo, conv.Fun) {
arg = conv.Args[0]
}
if u, ok := arg.(*ast.UnaryExpr); ok && u.Op == token.AND {
if !typeOKForCgoCall(cgoBaseType(pass.TypesInfo, u.X), make(map[types.Type]bool)) {
pass.Reportf(arg.Pos(), "possibly passing Go type with embedded pointer to C")
break
}
}
}
return true
})
return nil, nil
}
// findCall returns the CallExpr that we need to check, which may not be
// the same as the one we're currently visiting, due to code generation.
// It also returns the name of the function, such as "f" for C.f(...).
//
// This checker was initially written in vet to inpect unprocessed cgo
// source files using partial type information. However, Analyzers in
// the new analysis API are presented with the type-checked, processed
// Go ASTs resulting from cgo processing files, so we must choose
// between:
//
// a) locating the cgo file (e.g. from //line directives)
// and working with that, or
// b) working with the file generated by cgo.
//
// We cannot use (a) because it does not provide type information, which
// the analyzer needs, and it is infeasible for the analyzer to run the
// type checker on this file. Thus we choose (b), which is fragile,
// because the checker may need to change each time the cgo processor
// changes.
//
// Consider a cgo source file containing this header:
//
// /* void f(void *x, *y); */
// import "C"
//
// The cgo tool expands a call such as:
//
// C.f(x, y)
//
// to this:
//
// 1 func(param0, param1 unsafe.Pointer) {
// 2 ... various checks on params ...
// 3 (_Cfunc_f)(param0, param1)
// 4 }(x, y)
//
// We first locate the _Cfunc_f call on line 3, then
// walk up the stack of enclosing nodes until we find
// the call on line 4.
//
func findCall(fset *token.FileSet, stack []ast.Node) (*ast.CallExpr, string) {
last := len(stack) - 1
call := stack[last].(*ast.CallExpr)
if id, ok := analysisutil.Unparen(call.Fun).(*ast.Ident); ok {
if name := strings.TrimPrefix(id.Name, "_Cfunc_"); name != id.Name {
// Find the outer call with the arguments (x, y) we want to check.
for i := last - 1; i >= 0; i-- {
if outer, ok := stack[i].(*ast.CallExpr); ok {
return outer, name
}
}
// This shouldn't happen.
// Perhaps the code generator has changed?
log.Printf("%s: can't find outer call for C.%s(...)",
fset.Position(call.Lparen), name)
}
}
return nil, ""
}
// cgoBaseType tries to look through type conversions involving
// unsafe.Pointer to find the real type. It converts:
// unsafe.Pointer(x) => x
// *(*unsafe.Pointer)(unsafe.Pointer(&x)) => x
func cgoBaseType(info *types.Info, arg ast.Expr) types.Type {
switch arg := arg.(type) {
case *ast.CallExpr:
if len(arg.Args) == 1 && isUnsafePointer(info, arg.Fun) {
return cgoBaseType(info, arg.Args[0])
}
case *ast.StarExpr:
call, ok := arg.X.(*ast.CallExpr)
if !ok || len(call.Args) != 1 {
break
}
// Here arg is *f(v).
t := info.Types[call.Fun].Type
if t == nil {
break
}
ptr, ok := t.Underlying().(*types.Pointer)
if !ok {
break
}
// Here arg is *(*p)(v)
elem, ok := ptr.Elem().Underlying().(*types.Basic)
if !ok || elem.Kind() != types.UnsafePointer {
break
}
// Here arg is *(*unsafe.Pointer)(v)
call, ok = call.Args[0].(*ast.CallExpr)
if !ok || len(call.Args) != 1 {
break
}
// Here arg is *(*unsafe.Pointer)(f(v))
if !isUnsafePointer(info, call.Fun) {
break
}
// Here arg is *(*unsafe.Pointer)(unsafe.Pointer(v))
u, ok := call.Args[0].(*ast.UnaryExpr)
if !ok || u.Op != token.AND {
break
}
// Here arg is *(*unsafe.Pointer)(unsafe.Pointer(&v))
return cgoBaseType(info, u.X)
}
return info.Types[arg].Type
}
// typeOKForCgoCall reports whether the type of arg is OK to pass to a
// C function using cgo. This is not true for Go types with embedded
// pointers. m is used to avoid infinite recursion on recursive types.
func typeOKForCgoCall(t types.Type, m map[types.Type]bool) bool {
if t == nil || m[t] {
return true
}
m[t] = true
switch t := t.Underlying().(type) {
case *types.Chan, *types.Map, *types.Signature, *types.Slice:
return false
case *types.Pointer:
return typeOKForCgoCall(t.Elem(), m)
case *types.Array:
return typeOKForCgoCall(t.Elem(), m)
case *types.Struct:
for i := 0; i < t.NumFields(); i++ {
if !typeOKForCgoCall(t.Field(i).Type(), m) {
return false
}
}
}
return true
}
func isUnsafePointer(info *types.Info, e ast.Expr) bool {
t := info.Types[e].Type
return t != nil && t.Underlying() == types.Typ[types.UnsafePointer]
}
src/cmd/vendor/golang.org/x/tools/go/analysis/passes/composite/composite.go 0 → 100644
View file @ 8b469209
// Copyright 2012 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
// Package composite defines an Analyzer that checks for unkeyed
// composite literals.
package composite
import (
"go/ast"
"go/types"
"strings"
"golang.org/x/tools/go/analysis"
"golang.org/x/tools/go/analysis/passes/inspect"
"golang.org/x/tools/go/ast/inspector"
)
const Doc = `checked for unkeyed composite literals
This analyzer reports a diagnostic for composite literals of struct
types imported from another package that do not use the field-keyed
syntax. Such literals are fragile because the addition of a new field
(even if unexported) to the struct will cause compilation to fail.`
var Analyzer = &analysis.Analyzer{
Name: "composites",
Doc: Doc,
Requires: []*analysis.Analyzer{inspect.Analyzer},
RunDespiteErrors: true,
Run: run,
}
var whitelist = true
func init() {
Analyzer.Flags.BoolVar(&whitelist, "whitelist", whitelist, "use composite white list; for testing only")
}
// runUnkeyedLiteral checks if a composite literal is a struct literal with
// unkeyed fields.
func run(pass *analysis.Pass) (interface{}, error) {
inspect := pass.ResultOf[inspect.Analyzer].(*inspector.Inspector)
nodeFilter := []ast.Node{
(*ast.CompositeLit)(nil),
}
inspect.Preorder(nodeFilter, func(n ast.Node) {
cl := n.(*ast.CompositeLit)
typ := pass.TypesInfo.Types[cl].Type
if typ == nil {
// cannot determine composite literals' type, skip it
return
}
typeName := typ.String()
if whitelist && unkeyedLiteral[typeName] {
// skip whitelisted types
return
}
under := typ.Underlying()
for {
ptr, ok := under.(*types.Pointer)
if !ok {
break
}
under = ptr.Elem().Underlying()
}
if _, ok := under.(*types.Struct); !ok {
// skip non-struct composite literals
return
}
if isLocalType(pass, typ) {
// allow unkeyed locally defined composite literal
return
}
// check if the CompositeLit contains an unkeyed field
allKeyValue := true
for _, e := range cl.Elts {
if _, ok := e.(*ast.KeyValueExpr); !ok {
allKeyValue = false
break
}
}
if allKeyValue {
// all the composite literal fields are keyed
return
}
pass.Reportf(cl.Pos(), "%s composite literal uses unkeyed fields", typeName)
})
return nil, nil
}
func isLocalType(pass *analysis.Pass, typ types.Type) bool {
switch x := typ.(type) {
case *types.Struct:
// struct literals are local types
return true
case *types.Pointer:
return isLocalType(pass, x.Elem())
case *types.Named:
// names in package foo are local to foo_test too
return strings.TrimSuffix(x.Obj().Pkg().Path(), "_test") == strings.TrimSuffix(pass.Pkg.Path(), "_test")
}
return false
}
src/cmd/vendor/golang.org/x/tools/go/analysis/passes/composite/whitelist.go 0 → 100644
View file @ 8b469209
// Copyright 2013 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
package composite
// unkeyedLiteral is a white list of types in the standard packages
// that are used with unkeyed literals we deem to be acceptable.
var unkeyedLiteral = map[string]bool{
// These image and image/color struct types are frozen. We will never add fields to them.
"image/color.Alpha16": true,
"image/color.Alpha": true,
"image/color.CMYK": true,
"image/color.Gray16": true,
"image/color.Gray": true,
"image/color.NRGBA64": true,
"image/color.NRGBA": true,
"image/color.NYCbCrA": true,
"image/color.RGBA64": true,
"image/color.RGBA": true,
"image/color.YCbCr": true,
"image.Point": true,
"image.Rectangle": true,
"image.Uniform": true,
"unicode.Range16": true,
// These three structs are used in generated test main files,
// but the generator can be trusted.
"testing.InternalBenchmark": true,
"testing.InternalExample": true,
"testing.InternalTest": true,
}
src/cmd/vendor/golang.org/x/tools/go/analysis/passes/copylock/copylock.go 0 → 100644
View file @ 8b469209
// Copyright 2013 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
// Package copylock defines an Analyzer that checks for locks
// erroneously passed by value.
package copylock
import (
"bytes"
"fmt"
"go/ast"
"go/token"
"go/types"
"golang.org/x/tools/go/analysis"
"golang.org/x/tools/go/analysis/passes/inspect"
"golang.org/x/tools/go/analysis/passes/internal/analysisutil"
"golang.org/x/tools/go/ast/inspector"
)
const Doc = `check for locks erroneously passed by value
Inadvertently copying a value containing a lock, such as sync.Mutex or
sync.WaitGroup, may cause both copies to malfunction. Generally such
values should be referred to through a pointer.`
var Analyzer = &analysis.Analyzer{
Name: "copylocks",
Doc: Doc,
Requires: []*analysis.Analyzer{inspect.Analyzer},
RunDespiteErrors: true,
Run: run,
}
func run(pass *analysis.Pass) (interface{}, error) {
inspect := pass.ResultOf[inspect.Analyzer].(*inspector.Inspector)
nodeFilter := []ast.Node{
(*ast.AssignStmt)(nil),
(*ast.CallExpr)(nil),
(*ast.CompositeLit)(nil),
(*ast.FuncDecl)(nil),
(*ast.FuncLit)(nil),
(*ast.GenDecl)(nil),
(*ast.RangeStmt)(nil),
(*ast.ReturnStmt)(nil),
}
inspect.Preorder(nodeFilter, func(node ast.Node) {
switch node := node.(type) {
case *ast.RangeStmt:
checkCopyLocksRange(pass, node)
case *ast.FuncDecl:
checkCopyLocksFunc(pass, node.Name.Name, node.Recv, node.Type)
case *ast.FuncLit:
checkCopyLocksFunc(pass, "func", nil, node.Type)
case *ast.CallExpr:
checkCopyLocksCallExpr(pass, node)
case *ast.AssignStmt:
checkCopyLocksAssign(pass, node)
case *ast.GenDecl:
checkCopyLocksGenDecl(pass, node)
case *ast.CompositeLit:
checkCopyLocksCompositeLit(pass, node)
case *ast.ReturnStmt:
checkCopyLocksReturnStmt(pass, node)
}
})
return nil, nil
}
// checkCopyLocksAssign checks whether an assignment
// copies a lock.
func checkCopyLocksAssign(pass *analysis.Pass, as *ast.AssignStmt) {
for i, x := range as.Rhs {
if path := lockPathRhs(pass, x); path != nil {
pass.Reportf(x.Pos(), "assignment copies lock value to %v: %v", analysisutil.Format(pass.Fset, as.Lhs[i]), path)
}
}
}
// checkCopyLocksGenDecl checks whether lock is copied
// in variable declaration.
func checkCopyLocksGenDecl(pass *analysis.Pass, gd *ast.GenDecl) {
if gd.Tok != token.VAR {
return
}
for _, spec := range gd.Specs {
valueSpec := spec.(*ast.ValueSpec)
for i, x := range valueSpec.Values {
if path := lockPathRhs(pass, x); path != nil {
pass.Reportf(x.Pos(), "variable declaration copies lock value to %v: %v", valueSpec.Names[i].Name, path)
}
}
}
}
// checkCopyLocksCompositeLit detects lock copy inside a composite literal
func checkCopyLocksCompositeLit(pass *analysis.Pass, cl *ast.CompositeLit) {
for _, x := range cl.Elts {
if node, ok := x.(*ast.KeyValueExpr); ok {
x = node.Value
}
if path := lockPathRhs(pass, x); path != nil {
pass.Reportf(x.Pos(), "literal copies lock value from %v: %v", analysisutil.Format(pass.Fset, x), path)
}
}
}
// checkCopyLocksReturnStmt detects lock copy in return statement
func checkCopyLocksReturnStmt(pass *analysis.Pass, rs *ast.ReturnStmt) {
for _, x := range rs.Results {
if path := lockPathRhs(pass, x); path != nil {
pass.Reportf(x.Pos(), "return copies lock value: %v", path)
}
}
}
// checkCopyLocksCallExpr detects lock copy in the arguments to a function call
func checkCopyLocksCallExpr(pass *analysis.Pass, ce *ast.CallExpr) {
var id *ast.Ident
switch fun := ce.Fun.(type) {
case *ast.Ident:
id = fun
case *ast.SelectorExpr:
id = fun.Sel
}
if fun, ok := pass.TypesInfo.Uses[id].(*types.Builtin); ok {
switch fun.Name() {
case "new", "len", "cap", "Sizeof":
return
}
}
for _, x := range ce.Args {
if path := lockPathRhs(pass, x); path != nil {
pass.Reportf(x.Pos(), "call of %s copies lock value: %v", analysisutil.Format(pass.Fset, ce.Fun), path)
}
}
}
// checkCopyLocksFunc checks whether a function might
// inadvertently copy a lock, by checking whether
// its receiver, parameters, or return values
// are locks.
func checkCopyLocksFunc(pass *analysis.Pass, name string, recv *ast.FieldList, typ *ast.FuncType) {
if recv != nil && len(recv.List) > 0 {
expr := recv.List[0].Type
if path := lockPath(pass.Pkg, pass.TypesInfo.Types[expr].Type); path != nil {
pass.Reportf(expr.Pos(), "%s passes lock by value: %v", name, path)
}
}
if typ.Params != nil {
for _, field := range typ.Params.List {
expr := field.Type
if path := lockPath(pass.Pkg, pass.TypesInfo.Types[expr].Type); path != nil {
pass.Reportf(expr.Pos(), "%s passes lock by value: %v", name, path)
}
}
}
// Don't check typ.Results. If T has a Lock field it's OK to write
// return T{}
// because that is returning the zero value. Leave result checking
// to the return statement.
}
// checkCopyLocksRange checks whether a range statement
// might inadvertently copy a lock by checking whether
// any of the range variables are locks.
func checkCopyLocksRange(pass *analysis.Pass, r *ast.RangeStmt) {
checkCopyLocksRangeVar(pass, r.Tok, r.Key)
checkCopyLocksRangeVar(pass, r.Tok, r.Value)
}
func checkCopyLocksRangeVar(pass *analysis.Pass, rtok token.Token, e ast.Expr) {
if e == nil {
return
}
id, isId := e.(*ast.Ident)
if isId && id.Name == "_" {
return
}
var typ types.Type
if rtok == token.DEFINE {
if !isId {
return
}
obj := pass.TypesInfo.Defs[id]
if obj == nil {
return
}
typ = obj.Type()
} else {
typ = pass.TypesInfo.Types[e].Type
}
if typ == nil {
return
}
if path := lockPath(pass.Pkg, typ); path != nil {
pass.Reportf(e.Pos(), "range var %s copies lock: %v", analysisutil.Format(pass.Fset, e), path)
}
}
type typePath []types.Type
// String pretty-prints a typePath.
func (path typePath) String() string {
n := len(path)
var buf bytes.Buffer
for i := range path {
if i > 0 {
fmt.Fprint(&buf, " contains ")
}
// The human-readable path is in reverse order, outermost to innermost.
fmt.Fprint(&buf, path[n-i-1].String())
}
return buf.String()
}
func lockPathRhs(pass *analysis.Pass, x ast.Expr) typePath {
if _, ok := x.(*ast.CompositeLit); ok {
return nil
}
if _, ok := x.(*ast.CallExpr); ok {
// A call may return a zero value.
return nil
}
if star, ok := x.(*ast.StarExpr); ok {
if _, ok := star.X.(*ast.CallExpr); ok {
// A call may return a pointer to a zero value.
return nil
}
}
return lockPath(pass.Pkg, pass.TypesInfo.Types[x].Type)
}
// lockPath returns a typePath describing the location of a lock value
// contained in typ. If there is no contained lock, it returns nil.
func lockPath(tpkg *types.Package, typ types.Type) typePath {
if typ == nil {
return nil
}
for {
atyp, ok := typ.Underlying().(*types.Array)
if !ok {
break
}
typ = atyp.Elem()
}
// We're only interested in the case in which the underlying
// type is a struct. (Interfaces and pointers are safe to copy.)
styp, ok := typ.Underlying().(*types.Struct)
if !ok {
return nil
}
// We're looking for cases in which a pointer to this type
// is a sync.Locker, but a value is not. This differentiates
// embedded interfaces from embedded values.
if types.Implements(types.NewPointer(typ), lockerType) && !types.Implements(typ, lockerType) {
return []types.Type{typ}
}
// In go1.10, sync.noCopy did not implement Locker.
// (The Unlock method was added only in CL 121876.)
// TODO(adonovan): remove workaround when we drop go1.10.
if named, ok := typ.(*types.Named); ok &&
named.Obj().Name() == "noCopy" &&
named.Obj().Pkg().Path() == "sync" {
return []types.Type{typ}
}
nfields := styp.NumFields()
for i := 0; i < nfields; i++ {
ftyp := styp.Field(i).Type()
subpath := lockPath(tpkg, ftyp)
if subpath != nil {
return append(subpath, typ)
}
}
return nil
}
var lockerType *types.Interface
// Construct a sync.Locker interface type.
func init() {
nullary := types.NewSignature(nil, nil, nil, false) // func()
methods := []*types.Func{
types.NewFunc(token.NoPos, nil, "Lock", nullary),
types.NewFunc(token.NoPos, nil, "Unlock", nullary),
}
lockerType = types.NewInterface(methods, nil).Complete()
}
src/cmd/vendor/golang.org/x/tools/go/analysis/passes/ctrlflow/ctrlflow.go 0 → 100644
View file @ 8b469209
// Copyright 2018 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
// Package ctrlflow is an analysis that provides a syntactic
// control-flow graph (CFG) for the body of a function.
// It records whether a function cannot return.
// By itself, it does not report any diagnostics.
package ctrlflow
import (
"go/ast"
"go/types"
"log"
"reflect"
"golang.org/x/tools/go/analysis"
"golang.org/x/tools/go/analysis/passes/inspect"
"golang.org/x/tools/go/ast/inspector"
"golang.org/x/tools/go/cfg"
"golang.org/x/tools/go/types/typeutil"
)
var Analyzer = &analysis.Analyzer{
Name: "ctrlflow",
Doc: "build a control-flow graph",
Run: run,
ResultType: reflect.TypeOf(new(CFGs)),
FactTypes: []analysis.Fact{new(noReturn)},
Requires: []*analysis.Analyzer{inspect.Analyzer},
}
// noReturn is a fact indicating that a function does not return.
type noReturn struct{}
func (*noReturn) AFact() {}
func (*noReturn) String() string { return "noReturn" }
// A CFGs holds the control-flow graphs
// for all the functions of the current package.
type CFGs struct {
defs map[*ast.Ident]types.Object // from Pass.TypesInfo.Defs
funcDecls map[*types.Func]*declInfo
funcLits map[*ast.FuncLit]*litInfo
pass *analysis.Pass // transient; nil after construction
}
// CFGs has two maps: funcDecls for named functions and funcLits for
// unnamed ones. Unlike funcLits, the funcDecls map is not keyed by its
// syntax node, *ast.FuncDecl, because callMayReturn needs to do a
// look-up by *types.Func, and you can get from an *ast.FuncDecl to a
// *types.Func but not the other way.
type declInfo struct {
decl *ast.FuncDecl
cfg *cfg.CFG // iff decl.Body != nil
started bool // to break cycles
noReturn bool
}
type litInfo struct {
cfg *cfg.CFG
noReturn bool
}
// FuncDecl returns the control-flow graph for a named function.
// It returns nil if decl.Body==nil.
func (c *CFGs) FuncDecl(decl *ast.FuncDecl) *cfg.CFG {
if decl.Body == nil {
return nil
}
fn := c.defs[decl.Name].(*types.Func)
return c.funcDecls[fn].cfg
}
// FuncLit returns the control-flow graph for a literal function.
func (c *CFGs) FuncLit(lit *ast.FuncLit) *cfg.CFG {
return c.funcLits[lit].cfg
}
func run(pass *analysis.Pass) (interface{}, error) {
inspect := pass.ResultOf[inspect.Analyzer].(*inspector.Inspector)
// Because CFG construction consumes and produces noReturn
// facts, CFGs for exported FuncDecls must be built before 'run'
// returns; we cannot construct them lazily.
// (We could build CFGs for FuncLits lazily,
// but the benefit is marginal.)
// Pass 1. Map types.Funcs to ast.FuncDecls in this package.
funcDecls := make(map[*types.Func]*declInfo) // functions and methods
funcLits := make(map[*ast.FuncLit]*litInfo)
var decls []*types.Func // keys(funcDecls), in order
var lits []*ast.FuncLit // keys(funcLits), in order
nodeFilter := []ast.Node{
(*ast.FuncDecl)(nil),
(*ast.FuncLit)(nil),
}
inspect.Preorder(nodeFilter, func(n ast.Node) {
switch n := n.(type) {
case *ast.FuncDecl:
fn := pass.TypesInfo.Defs[n.Name].(*types.Func)
funcDecls[fn] = &declInfo{decl: n}
decls = append(decls, fn)
case *ast.FuncLit:
funcLits[n] = new(litInfo)
lits = append(lits, n)
}
})
c := &CFGs{
defs: pass.TypesInfo.Defs,
funcDecls: funcDecls,
funcLits: funcLits,
pass: pass,
}
// Pass 2. Build CFGs.
// Build CFGs for named functions.
// Cycles in the static call graph are broken
// arbitrarily but deterministically.
// We create noReturn facts as discovered.
for _, fn := range decls {
c.buildDecl(fn, funcDecls[fn])
}
// Build CFGs for literal functions.
// These aren't relevant to facts (since they aren't named)
// but are required for the CFGs.FuncLit API.
for _, lit := range lits {
li := funcLits[lit]
if li.cfg == nil {
li.cfg = cfg.New(lit.Body, c.callMayReturn)
if !hasReachableReturn(li.cfg) {
li.noReturn = true
}
}
}
// All CFGs are now built.
c.pass = nil
return c, nil
}
// di.cfg may be nil on return.
func (c *CFGs) buildDecl(fn *types.Func, di *declInfo) {
// buildDecl may call itself recursively for the same function,
// because cfg.New is passed the callMayReturn method, which
// builds the CFG of the callee, leading to recursion.
// The buildDecl call tree thus resembles the static call graph.
// We mark each node when we start working on it to break cycles.
if !di.started { // break cycle
di.started = true
if isIntrinsicNoReturn(fn) {
di.noReturn = true
}
if di.decl.Body != nil {
di.cfg = cfg.New(di.decl.Body, c.callMayReturn)
if !hasReachableReturn(di.cfg) {
di.noReturn = true
}
}
if di.noReturn {
c.pass.ExportObjectFact(fn, new(noReturn))
}
// debugging
if false {
log.Printf("CFG for %s:\n%s (noreturn=%t)\n", fn, di.cfg.Format(c.pass.Fset), di.noReturn)
}
}
}
// callMayReturn reports whether the called function may return.
// It is passed to the CFG builder.
func (c *CFGs) callMayReturn(call *ast.CallExpr) (r bool) {
if id, ok := call.Fun.(*ast.Ident); ok && c.pass.TypesInfo.Uses[id] == panicBuiltin {
return false // panic never returns
}
// Is this a static call?
fn := typeutil.StaticCallee(c.pass.TypesInfo, call)
if fn == nil {
return true // callee not statically known; be conservative
}
// Function or method declared in this package?
if di, ok := c.funcDecls[fn]; ok {
c.buildDecl(fn, di)
return !di.noReturn
}
// Not declared in this package.
// Is there a fact from another package?
return !c.pass.ImportObjectFact(fn, new(noReturn))
}
var panicBuiltin = types.Universe.Lookup("panic").(*types.Builtin)
func hasReachableReturn(g *cfg.CFG) bool {
for _, b := range g.Blocks {
if b.Live && b.Return() != nil {
return true
}
}
return false
}
// isIntrinsicNoReturn reports whether a function intrinsically never
// returns because it stops execution of the calling thread.
// It is the base case in the recursion.
func isIntrinsicNoReturn(fn *types.Func) bool {
// Add functions here as the need arises, but don't allocate memory.
path, name := fn.Pkg().Path(), fn.Name()
return path == "syscall" && (name == "Exit" || name == "ExitProcess" || name == "ExitThread") ||
path == "runtime" && name == "Goexit"
}
src/cmd/vendor/golang.org/x/tools/go/analysis/passes/httpresponse/httpresponse.go 0 → 100644
View file @ 8b469209
// Copyright 2016 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
// Package httpresponse defines an Analyzer that checks for mistakes
// using HTTP responses.
package httpresponse
import (
"go/ast"
"go/types"
"golang.org/x/tools/go/analysis"
"golang.org/x/tools/go/analysis/passes/inspect"
"golang.org/x/tools/go/ast/inspector"
)
const Doc = `check for mistakes using HTTP responses
A common mistake when using the net/http package is to defer a function
call to close the http.Response Body before checking the error that
determines whether the response is valid:
resp, err := http.Head(url)
defer resp.Body.Close()
if err != nil {
log.Fatal(err)
}
// (defer statement belongs here)
This checker helps uncover latent nil dereference bugs by reporting a
diagnostic for such mistakes.`
var Analyzer = &analysis.Analyzer{
Name: "httpresponse",
Doc: Doc,
Requires: []*analysis.Analyzer{inspect.Analyzer},
Run: run,
}
func run(pass *analysis.Pass) (interface{}, error) {
inspect := pass.ResultOf[inspect.Analyzer].(*inspector.Inspector)
// Fast path: if the package doesn't import net/http,
// skip the traversal.
if !imports(pass.Pkg, "net/http") {
return nil, nil
}
nodeFilter := []ast.Node{
(*ast.CallExpr)(nil),
}
inspect.WithStack(nodeFilter, func(n ast.Node, push bool, stack []ast.Node) bool {
if !push {
return true
}
call := n.(*ast.CallExpr)
if !isHTTPFuncOrMethodOnClient(pass.TypesInfo, call) {
return true // the function call is not related to this check.
}
// Find the innermost containing block, and get the list
// of statements starting with the one containing call.
stmts := restOfBlock(stack)
if len(stmts) < 2 {
return true // the call to the http function is the last statement of the block.
}
asg, ok := stmts[0].(*ast.AssignStmt)
if !ok {
return true // the first statement is not assignment.
}
resp := rootIdent(asg.Lhs[0])
if resp == nil {
return true // could not find the http.Response in the assignment.
}
def, ok := stmts[1].(*ast.DeferStmt)
if !ok {
return true // the following statement is not a defer.
}
root := rootIdent(def.Call.Fun)
if root == nil {
return true // could not find the receiver of the defer call.
}
if resp.Obj == root.Obj {
pass.Reportf(root.Pos(), "using %s before checking for errors", resp.Name)
}
return true
})
return nil, nil
}
// isHTTPFuncOrMethodOnClient checks whether the given call expression is on
// either a function of the net/http package or a method of http.Client that
// returns (*http.Response, error).
func isHTTPFuncOrMethodOnClient(info *types.Info, expr *ast.CallExpr) bool {
fun, _ := expr.Fun.(*ast.SelectorExpr)
sig, _ := info.Types[fun].Type.(*types.Signature)
if sig == nil {
return false // the call is not of the form x.f()
}
res := sig.Results()
if res.Len() != 2 {
return false // the function called does not return two values.
}
if ptr, ok := res.At(0).Type().(*types.Pointer); !ok || !isNamedType(ptr.Elem(), "net/http", "Response") {
return false // the first return type is not *http.Response.
}
errorType := types.Universe.Lookup("error").Type()
if !types.Identical(res.At(1).Type(), errorType) {
return false // the second return type is not error
}
typ := info.Types[fun.X].Type
if typ == nil {
id, ok := fun.X.(*ast.Ident)
return ok && id.Name == "http" // function in net/http package.
}
if isNamedType(typ, "net/http", "Client") {
return true // method on http.Client.
}
ptr, ok := typ.(*types.Pointer)
return ok && isNamedType(ptr.Elem(), "net/http", "Client") // method on *http.Client.
}
// restOfBlock, given a traversal stack, finds the innermost containing
// block and returns the suffix of its statements starting with the
// current node (the last element of stack).
func restOfBlock(stack []ast.Node) []ast.Stmt {
for i := len(stack) - 1; i >= 0; i-- {
if b, ok := stack[i].(*ast.BlockStmt); ok {
for j, v := range b.List {
if v == stack[i+1] {
return b.List[j:]
}
}
break
}
}
return nil
}
// rootIdent finds the root identifier x in a chain of selections x.y.z, or nil if not found.
func rootIdent(n ast.Node) *ast.Ident {
switch n := n.(type) {
case *ast.SelectorExpr:
return rootIdent(n.X)
case *ast.Ident:
return n
default:
return nil
}
}
// isNamedType reports whether t is the named type path.name.
func isNamedType(t types.Type, path, name string) bool {
n, ok := t.(*types.Named)
if !ok {
return false
}
obj := n.Obj()
return obj.Name() == name && obj.Pkg() != nil && obj.Pkg().Path() == path
}
func imports(pkg *types.Package, path string) bool {
for _, imp := range pkg.Imports() {
if imp.Path() == path {
return true
}
}
return false
}
src/cmd/vendor/golang.org/x/tools/go/analysis/passes/inspect/inspect.go 0 → 100644
View file @ 8b469209
// Copyright 2018 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
// Package inspect defines an Analyzer that provides an AST inspector
// (golang.org/x/tools/go/ast/inspect.Inspect) for the syntax trees of a
// package. It is only a building block for other analyzers.
//
// Example of use in another analysis:
//
// import "golang.org/x/tools/go/analysis/passes/inspect"
//
// var Analyzer = &analysis.Analyzer{
// ...
// Requires: reflect.TypeOf(new(inspect.Analyzer)),
// }
//
// func run(pass *analysis.Pass) (interface{}, error) {
// inspect := pass.ResultOf[inspect.Analyzer].(*inspector.Inspector)
// inspect.Preorder(nil, func(n ast.Node) {
// ...
// })
// return nil
// }
//
package inspect
import (
"reflect"
"golang.org/x/tools/go/analysis"
"golang.org/x/tools/go/ast/inspector"
)
var Analyzer = &analysis.Analyzer{
Name: "inspect",
Doc: "optimize AST traversal for later passes",
Run: run,
RunDespiteErrors: true,
ResultType: reflect.TypeOf(new(inspector.Inspector)),
}
func run(pass *analysis.Pass) (interface{}, error) {
return inspector.New(pass.Files), nil
}
src/cmd/vendor/golang.org/x/tools/go/analysis/passes/internal/analysisutil/util.go 0 → 100644
View file @ 8b469209
// Package analysisutil defines various helper functions
// used by two or more packages beneath go/analysis.
package analysisutil
import (
"bytes"
"go/ast"
"go/printer"
"go/token"
"go/types"
"io/ioutil"
)
// Format returns a string representation of the expression.
func Format(fset *token.FileSet, x ast.Expr) string {
var b bytes.Buffer
printer.Fprint(&b, fset, x)
return b.String()
}
// HasSideEffects reports whether evaluation of e has side effects.
func HasSideEffects(info *types.Info, e ast.Expr) bool {
safe := true
ast.Inspect(e, func(node ast.Node) bool {
switch n := node.(type) {
case *ast.CallExpr:
typVal := info.Types[n.Fun]
switch {
case typVal.IsType():
// Type conversion, which is safe.
case typVal.IsBuiltin():
// Builtin func, conservatively assumed to not
// be safe for now.
safe = false
return false
default:
// A non-builtin func or method call.
// Conservatively assume that all of them have
// side effects for now.
safe = false
return false
}
case *ast.UnaryExpr:
if n.Op == token.ARROW {
safe = false
return false
}
}
return true
})
return !safe
}
// Unparen returns e with any enclosing parentheses stripped.
func Unparen(e ast.Expr) ast.Expr {
for {
p, ok := e.(*ast.ParenExpr)
if !ok {
return e
}
e = p.X
}
}
// ReadFile reads a file and adds it to the FileSet
// so that we can report errors against it using lineStart.
func ReadFile(fset *token.FileSet, filename string) ([]byte, *token.File, error) {
content, err := ioutil.ReadFile(filename)
if err != nil {
return nil, nil, err
}
tf := fset.AddFile(filename, -1, len(content))
tf.SetLinesForContent(content)
return content, tf, nil
}
// LineStart returns the position of the start of the specified line
// within file f, or NoPos if there is no line of that number.
func LineStart(f *token.File, line int) token.Pos {
// Use binary search to find the start offset of this line.
//
// TODO(adonovan): eventually replace this function with the
// simpler and more efficient (*go/token.File).LineStart, added
// in go1.12.
min := 0 // inclusive
max := f.Size() // exclusive
for {
offset := (min + max) / 2
pos := f.Pos(offset)
posn := f.Position(pos)
if posn.Line == line {
return pos - (token.Pos(posn.Column) - 1)
}
if min+1 >= max {
return token.NoPos
}
if posn.Line < line {
min = offset
} else {
max = offset
}
}
}
src/cmd/vendor/golang.org/x/tools/go/analysis/passes/loopclosure/loopclosure.go 0 → 100644
View file @ 8b469209
// Copyright 2012 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
// Package loopclosure defines an Analyzer that checks for references to
// enclosing loop variables from within nested functions.
package loopclosure
import (
"go/ast"
"golang.org/x/tools/go/analysis"
"golang.org/x/tools/go/analysis/passes/inspect"
"golang.org/x/tools/go/ast/inspector"
)
// TODO(adonovan): also report an error for the following structure,
// which is often used to ensure that deferred calls do not accumulate
// in a loop:
//
// for i, x := range c {
// func() {
// ...reference to i or x...
// }()
// }
const Doc = `check references to loop variables from within nested functions
This analyzer checks for references to loop variables from within a
function literal inside the loop body. It checks only instances where
the function literal is called in a defer or go statement that is the
last statement in the loop body, as otherwise we would need whole
program analysis.
For example:
for i, v := range s {
go func() {
println(i, v) // not what you might expect
}()
}
See: https://golang.org/doc/go_faq.html#closures_and_goroutines`
var Analyzer = &analysis.Analyzer{
Name: "loopclosure",
Doc: Doc,
Requires: []*analysis.Analyzer{inspect.Analyzer},
Run: run,
}
func run(pass *analysis.Pass) (interface{}, error) {
inspect := pass.ResultOf[inspect.Analyzer].(*inspector.Inspector)
nodeFilter := []ast.Node{
(*ast.RangeStmt)(nil),
(*ast.ForStmt)(nil),
}
inspect.Preorder(nodeFilter, func(n ast.Node) {
// Find the variables updated by the loop statement.
var vars []*ast.Ident
addVar := func(expr ast.Expr) {
if id, ok := expr.(*ast.Ident); ok {
vars = append(vars, id)
}
}
var body *ast.BlockStmt
switch n := n.(type) {
case *ast.RangeStmt:
body = n.Body
addVar(n.Key)
addVar(n.Value)
case *ast.ForStmt:
body = n.Body
switch post := n.Post.(type) {
case *ast.AssignStmt:
// e.g. for p = head; p != nil; p = p.next
for _, lhs := range post.Lhs {
addVar(lhs)
}
case *ast.IncDecStmt:
// e.g. for i := 0; i < n; i++
addVar(post.X)
}
}
if vars == nil {
return
}
// Inspect a go or defer statement
// if it's the last one in the loop body.
// (We give up if there are following statements,
// because it's hard to prove go isn't followed by wait,
// or defer by return.)
if len(body.List) == 0 {
return
}
var last *ast.CallExpr
switch s := body.List[len(body.List)-1].(type) {
case *ast.GoStmt:
last = s.Call
case *ast.DeferStmt:
last = s.Call
default:
return
}
lit, ok := last.Fun.(*ast.FuncLit)
if !ok {
return
}
ast.Inspect(lit.Body, func(n ast.Node) bool {
id, ok := n.(*ast.Ident)
if !ok || id.Obj == nil {
return true
}
if pass.TypesInfo.Types[id].Type == nil {
// Not referring to a variable (e.g. struct field name)
return true
}
for _, v := range vars {
if v.Obj == id.Obj {
pass.Reportf(id.Pos(), "loop variable %s captured by func literal",
id.Name)
}
}
return true
})
})
return nil, nil
}
src/cmd/vendor/golang.org/x/tools/go/analysis/passes/lostcancel/lostcancel.go 0 → 100644
View file @ 8b469209
// Copyright 2016 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
// Package lostcancel defines an Analyzer that checks for failure to
// call a context cancelation function.
package lostcancel
import (
"fmt"
"go/ast"
"go/types"
"golang.org/x/tools/go/analysis"
"golang.org/x/tools/go/analysis/passes/ctrlflow"
"golang.org/x/tools/go/analysis/passes/inspect"
"golang.org/x/tools/go/ast/inspector"
"golang.org/x/tools/go/cfg"
)
const Doc = `check cancel func returned by context.WithCancel is called
The cancelation function returned by context.WithCancel, WithTimeout,
and WithDeadline must be called or the new context will remain live
until its parent context is cancelled.
(The background context is never cancelled.)`
var Analyzer = &analysis.Analyzer{
Name: "lostcancel",
Doc: Doc,
Run: run,
Requires: []*analysis.Analyzer{
inspect.Analyzer,
ctrlflow.Analyzer,
},
}
const debug = false
var contextPackage = "context"
// checkLostCancel reports a failure to the call the cancel function
// returned by context.WithCancel, either because the variable was
// assigned to the blank identifier, or because there exists a
// control-flow path from the call to a return statement and that path
// does not "use" the cancel function. Any reference to the variable
// counts as a use, even within a nested function literal.
//
// checkLostCancel analyzes a single named or literal function.
func run(pass *analysis.Pass) (interface{}, error) {
// Fast path: bypass check if file doesn't use context.WithCancel.
if !hasImport(pass.Pkg, contextPackage) {
return nil, nil
}
// Call runFunc for each Func{Decl,Lit}.
inspect := pass.ResultOf[inspect.Analyzer].(*inspector.Inspector)
nodeTypes := []ast.Node{
(*ast.FuncLit)(nil),
(*ast.FuncDecl)(nil),
}
inspect.Preorder(nodeTypes, func(n ast.Node) {
runFunc(pass, n)
})
return nil, nil
}
func runFunc(pass *analysis.Pass, node ast.Node) {
// Maps each cancel variable to its defining ValueSpec/AssignStmt.
cancelvars := make(map[*types.Var]ast.Node)
// TODO(adonovan): opt: refactor to make a single pass
// over the AST using inspect.WithStack and node types
// {FuncDecl,FuncLit,CallExpr,SelectorExpr}.
// Find the set of cancel vars to analyze.
stack := make([]ast.Node, 0, 32)
ast.Inspect(node, func(n ast.Node) bool {
switch n.(type) {
case *ast.FuncLit:
if len(stack) > 0 {
return false // don't stray into nested functions
}
case nil:
stack = stack[:len(stack)-1] // pop
return true
}
stack = append(stack, n) // push
// Look for [{AssignStmt,ValueSpec} CallExpr SelectorExpr]:
//
// ctx, cancel := context.WithCancel(...)
// ctx, cancel = context.WithCancel(...)
// var ctx, cancel = context.WithCancel(...)
//
if isContextWithCancel(pass.TypesInfo, n) && isCall(stack[len(stack)-2]) {
var id *ast.Ident // id of cancel var
stmt := stack[len(stack)-3]
switch stmt := stmt.(type) {
case *ast.ValueSpec:
if len(stmt.Names) > 1 {
id = stmt.Names[1]
}
case *ast.AssignStmt:
if len(stmt.Lhs) > 1 {
id, _ = stmt.Lhs[1].(*ast.Ident)
}
}
if id != nil {
if id.Name == "_" {
pass.Reportf(id.Pos(),
"the cancel function returned by context.%s should be called, not discarded, to avoid a context leak",
n.(*ast.SelectorExpr).Sel.Name)
} else if v, ok := pass.TypesInfo.Uses[id].(*types.Var); ok {
cancelvars[v] = stmt
} else if v, ok := pass.TypesInfo.Defs[id].(*types.Var); ok {
cancelvars[v] = stmt
}
}
}
return true
})
if len(cancelvars) == 0 {
return // no need to inspect CFG
}
// Obtain the CFG.
cfgs := pass.ResultOf[ctrlflow.Analyzer].(*ctrlflow.CFGs)
var g *cfg.CFG
var sig *types.Signature
switch node := node.(type) {
case *ast.FuncDecl:
g = cfgs.FuncDecl(node)
sig, _ = pass.TypesInfo.Defs[node.Name].Type().(*types.Signature)
case *ast.FuncLit:
g = cfgs.FuncLit(node)
sig, _ = pass.TypesInfo.Types[node.Type].Type.(*types.Signature)
}
if sig == nil {
return // missing type information
}
// Print CFG.
if debug {
fmt.Println(g.Format(pass.Fset))
}
// Examine the CFG for each variable in turn.
// (It would be more efficient to analyze all cancelvars in a
// single pass over the AST, but seldom is there more than one.)
for v, stmt := range cancelvars {
if ret := lostCancelPath(pass, g, v, stmt, sig); ret != nil {
lineno := pass.Fset.Position(stmt.Pos()).Line
pass.Reportf(stmt.Pos(), "the %s function is not used on all paths (possible context leak)", v.Name())
pass.Reportf(ret.Pos(), "this return statement may be reached without using the %s var defined on line %d", v.Name(), lineno)
}
}
}
func isCall(n ast.Node) bool { _, ok := n.(*ast.CallExpr); return ok }
func hasImport(pkg *types.Package, path string) bool {
for _, imp := range pkg.Imports() {
if imp.Path() == path {
return true
}
}
return false
}
// isContextWithCancel reports whether n is one of the qualified identifiers
// context.With{Cancel,Timeout,Deadline}.
func isContextWithCancel(info *types.Info, n ast.Node) bool {
if sel, ok := n.(*ast.SelectorExpr); ok {
switch sel.Sel.Name {
case "WithCancel", "WithTimeout", "WithDeadline":
if x, ok := sel.X.(*ast.Ident); ok {
if pkgname, ok := info.Uses[x].(*types.PkgName); ok {
return pkgname.Imported().Path() == contextPackage
}
// Import failed, so we can't check package path.
// Just check the local package name (heuristic).
return x.Name == "context"
}
}
}
return false
}
// lostCancelPath finds a path through the CFG, from stmt (which defines
// the 'cancel' variable v) to a return statement, that doesn't "use" v.
// If it finds one, it returns the return statement (which may be synthetic).
// sig is the function's type, if known.
func lostCancelPath(pass *analysis.Pass, g *cfg.CFG, v *types.Var, stmt ast.Node, sig *types.Signature) *ast.ReturnStmt {
vIsNamedResult := sig != nil && tupleContains(sig.Results(), v)
// uses reports whether stmts contain a "use" of variable v.
uses := func(pass *analysis.Pass, v *types.Var, stmts []ast.Node) bool {
found := false
for _, stmt := range stmts {
ast.Inspect(stmt, func(n ast.Node) bool {
switch n := n.(type) {
case *ast.Ident:
if pass.TypesInfo.Uses[n] == v {
found = true
}
case *ast.ReturnStmt:
// A naked return statement counts as a use
// of the named result variables.
if n.Results == nil && vIsNamedResult {
found = true
}
}
return !found
})
}
return found
}
// blockUses computes "uses" for each block, caching the result.
memo := make(map[*cfg.Block]bool)
blockUses := func(pass *analysis.Pass, v *types.Var, b *cfg.Block) bool {
res, ok := memo[b]
if !ok {
res = uses(pass, v, b.Nodes)
memo[b] = res
}
return res
}
// Find the var's defining block in the CFG,
// plus the rest of the statements of that block.
var defblock *cfg.Block
var rest []ast.Node
outer:
for _, b := range g.Blocks {
for i, n := range b.Nodes {
if n == stmt {
defblock = b
rest = b.Nodes[i+1:]
break outer
}
}
}
if defblock == nil {
panic("internal error: can't find defining block for cancel var")
}
// Is v "used" in the remainder of its defining block?
if uses(pass, v, rest) {
return nil
}
// Does the defining block return without using v?
if ret := defblock.Return(); ret != nil {
return ret
}
// Search the CFG depth-first for a path, from defblock to a
// return block, in which v is never "used".
seen := make(map[*cfg.Block]bool)
var search func(blocks []*cfg.Block) *ast.ReturnStmt
search = func(blocks []*cfg.Block) *ast.ReturnStmt {
for _, b := range blocks {
if !seen[b] {
seen[b] = true
// Prune the search if the block uses v.
if blockUses(pass, v, b) {
continue
}
// Found path to return statement?
if ret := b.Return(); ret != nil {
if debug {
fmt.Printf("found path to return in block %s\n", b)
}
return ret // found
}
// Recur
if ret := search(b.Succs); ret != nil {
if debug {
fmt.Printf(" from block %s\n", b)
}
return ret
}
}
}
return nil
}
return search(defblock.Succs)
}
func tupleContains(tuple *types.Tuple, v *types.Var) bool {
for i := 0; i < tuple.Len(); i++ {
if tuple.At(i) == v {
return true
}
}
return false
}
src/cmd/vendor/golang.org/x/tools/go/analysis/passes/nilfunc/nilfunc.go 0 → 100644
View file @ 8b469209
// Copyright 2013 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
// Package nilfunc defines an Analyzer that checks for useless
// comparisons against nil.
package nilfunc
import (
"go/ast"
"go/token"
"go/types"
"golang.org/x/tools/go/analysis"
"golang.org/x/tools/go/analysis/passes/inspect"
"golang.org/x/tools/go/ast/inspector"
)
const Doc = `check for useless comparisons between functions and nil
A useless comparison is one like f == nil as opposed to f() == nil.`
var Analyzer = &analysis.Analyzer{
Name: "nilfunc",
Doc: Doc,
Requires: []*analysis.Analyzer{inspect.Analyzer},
Run: run,
}
func run(pass *analysis.Pass) (interface{}, error) {
inspect := pass.ResultOf[inspect.Analyzer].(*inspector.Inspector)
nodeFilter := []ast.Node{
(*ast.BinaryExpr)(nil),
}
inspect.Preorder(nodeFilter, func(n ast.Node) {
e := n.(*ast.BinaryExpr)
// Only want == or != comparisons.
if e.Op != token.EQL && e.Op != token.NEQ {
return
}
// Only want comparisons with a nil identifier on one side.
var e2 ast.Expr
switch {
case pass.TypesInfo.Types[e.X].IsNil():
e2 = e.Y
case pass.TypesInfo.Types[e.Y].IsNil():
e2 = e.X
default:
return
}
// Only want identifiers or selector expressions.
var obj types.Object
switch v := e2.(type) {
case *ast.Ident:
obj = pass.TypesInfo.Uses[v]
case *ast.SelectorExpr:
obj = pass.TypesInfo.Uses[v.Sel]
default:
return
}
// Only want functions.
if _, ok := obj.(*types.Func); !ok {
return
}
pass.Reportf(e.Pos(), "comparison of function %v %v nil is always %v", obj.Name(), e.Op, e.Op == token.NEQ)
})
return nil, nil
}
src/cmd/vendor/golang.org/x/tools/go/analysis/passes/pkgfact/pkgfact.go 0 → 100644
View file @ 8b469209
// Copyright 2018 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
// The pkgfact package is a demonstration and test of the package fact
// mechanism.
//
// The output of the pkgfact analysis is a set of key/values pairs
// gathered from the analyzed package and its imported dependencies.
// Each key/value pair comes from a top-level constant declaration
// whose name starts and ends with "_". For example:
//
// package p
//
// const _greeting_ = "hello"
// const _audience_ = "world"
//
// the pkgfact analysis output for package p would be:
//
// {"greeting": "hello", "audience": "world"}.
//
// In addition, the analysis reports a diagnostic at each import
// showing which key/value pairs it contributes.
package pkgfact
import (
"fmt"
"go/ast"
"go/token"
"go/types"
"reflect"
"sort"
"strings"
"golang.org/x/tools/go/analysis"
)
var Analyzer = &analysis.Analyzer{
Name: "pkgfact",
Doc: "gather name/value pairs from constant declarations",
Run: run,
FactTypes: []analysis.Fact{new(pairsFact)},
ResultType: reflect.TypeOf(map[string]string{}),
}
// A pairsFact is a package-level fact that records
// an set of key=value strings accumulated from constant
// declarations in this package and its dependencies.
// Elements are ordered by keys, which are unique.
type pairsFact []string
func (f *pairsFact) AFact() {}
func (f *pairsFact) String() string { return "pairs(" + strings.Join(*f, ", ") + ")" }
func run(pass *analysis.Pass) (interface{}, error) {
result := make(map[string]string)
// At each import, print the fact from the imported
// package and accumulate its information into the result.
// (Warning: accumulation leads to quadratic growth of work.)
doImport := func(spec *ast.ImportSpec) {
pkg := imported(pass.TypesInfo, spec)
var fact pairsFact
if pass.ImportPackageFact(pkg, &fact) {
for _, pair := range fact {
eq := strings.IndexByte(pair, '=')
result[pair[:eq]] = pair[1+eq:]
}
pass.Reportf(spec.Pos(), "%s", strings.Join(fact, " "))
}
}
// At each "const _name_ = value", add a fact into env.
doConst := func(spec *ast.ValueSpec) {
if len(spec.Names) == len(spec.Values) {
for i := range spec.Names {
name := spec.Names[i].Name
if strings.HasPrefix(name, "_") && strings.HasSuffix(name, "_") {
if key := strings.Trim(name, "_"); key != "" {
value := pass.TypesInfo.Types[spec.Values[i]].Value.String()
result[key] = value
}
}
}
}
}
for _, f := range pass.Files {
for _, decl := range f.Decls {
if decl, ok := decl.(*ast.GenDecl); ok {
for _, spec := range decl.Specs {
switch decl.Tok {
case token.IMPORT:
doImport(spec.(*ast.ImportSpec))
case token.CONST:
doConst(spec.(*ast.ValueSpec))
}
}
}
}
}
// Sort/deduplicate the result and save it as a package fact.
keys := make([]string, 0, len(result))
for key := range result {
keys = append(keys, key)
}
sort.Strings(keys)
var fact pairsFact
for _, key := range keys {
fact = append(fact, fmt.Sprintf("%s=%s", key, result[key]))
}
if len(fact) > 0 {
pass.ExportPackageFact(&fact)
}
return result, nil
}
func imported(info *types.Info, spec *ast.ImportSpec) *types.Package {
obj, ok := info.Implicits[spec]
if !ok {
obj = info.Defs[spec.Name] // renaming import
}
return obj.(*types.PkgName).Imported()
}
src/cmd/vendor/golang.org/x/tools/go/analysis/passes/printf/printf.go 0 → 100644
View file @ 8b469209
// Copyright 2010 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
// This file contains the printf-checker.
package printf
import (
"bytes"
"fmt"
"go/ast"
"go/constant"
"go/token"
"go/types"
"regexp"
"sort"
"strconv"
"strings"
"unicode/utf8"
"golang.org/x/tools/go/analysis"
"golang.org/x/tools/go/analysis/passes/inspect"
"golang.org/x/tools/go/analysis/passes/internal/analysisutil"
"golang.org/x/tools/go/ast/inspector"
"golang.org/x/tools/go/types/typeutil"
)
func init() {
Analyzer.Flags.Var(isPrint, "funcs", "comma-separated list of print function names to check")
}
var Analyzer = &analysis.Analyzer{
Name: "printf",
Doc: "check printf-like invocations",
Requires: []*analysis.Analyzer{inspect.Analyzer},
Run: run,
FactTypes: []analysis.Fact{new(isWrapper)},
}
const doc = `check consistency of Printf format strings and arguments
The check applies to known functions (for example, those in package fmt)
as well as any detected wrappers of known functions.
A function that wants to avail itself of printf checking but does not
get found by this analyzer's heuristics (for example, due to use of
dynamic calls) can insert a bogus call:
if false {
fmt.Sprintf(format, args...) // enable printf checking
}
The -funcs flag specifies a comma-separated list of names of additional
known formatting functions or methods. If the name contains a period,
it must denote a specific function using one of the following forms:
dir/pkg.Function
dir/pkg.Type.Method
(*dir/pkg.Type).Method
Otherwise the name is interpreted as a case-insensitive unqualified
identifier such as "errorf". Either way, if a listed name ends in f, the
function is assumed to be Printf-like, taking a format string before the
argument list. Otherwise it is assumed to be Print-like, taking a list
of arguments with no format string.
`
// isWrapper is a fact indicating that a function is a print or printf wrapper.
type isWrapper struct{ Printf bool }
func (f *isWrapper) AFact() {}
func (f *isWrapper) String() string {
if f.Printf {
return "printfWrapper"
} else {
return "printWrapper"
}
}
func run(pass *analysis.Pass) (interface{}, error) {
findPrintfLike(pass)
checkCall(pass)
return nil, nil
}
type printfWrapper struct {
obj *types.Func
fdecl *ast.FuncDecl
format *types.Var
args *types.Var
callers []printfCaller
failed bool // if true, not a printf wrapper
}
type printfCaller struct {
w *printfWrapper
call *ast.CallExpr
}
// maybePrintfWrapper decides whether decl (a declared function) may be a wrapper
// around a fmt.Printf or fmt.Print function. If so it returns a printfWrapper
// function describing the declaration. Later processing will analyze the
// graph of potential printf wrappers to pick out the ones that are true wrappers.
// A function may be a Printf or Print wrapper if its last argument is ...interface{}.
// If the next-to-last argument is a string, then this may be a Printf wrapper.
// Otherwise it may be a Print wrapper.
func maybePrintfWrapper(info *types.Info, decl ast.Decl) *printfWrapper {
// Look for functions with final argument type ...interface{}.
fdecl, ok := decl.(*ast.FuncDecl)
if !ok || fdecl.Body == nil {
return nil
}
fn := info.Defs[fdecl.Name].(*types.Func)
sig := fn.Type().(*types.Signature)
if !sig.Variadic() {
return nil // not variadic
}
params := sig.Params()
nparams := params.Len() // variadic => nonzero
args := params.At(nparams - 1)
iface, ok := args.Type().(*types.Slice).Elem().(*types.Interface)
if !ok || !iface.Empty() {
return nil // final (args) param is not ...interface{}
}
// Is second last param 'format string'?
var format *types.Var
if nparams >= 2 {
if p := params.At(nparams - 2); p.Type() == types.Typ[types.String] {
format = p
}
}
return &printfWrapper{
obj: fn,
fdecl: fdecl,
format: format,
args: args,
}
}
// findPrintfLike scans the entire package to find printf-like functions.
func findPrintfLike(pass *analysis.Pass) (interface{}, error) {
// Gather potential wrappers and call graph between them.
byObj := make(map[*types.Func]*printfWrapper)
var wrappers []*printfWrapper
for _, file := range pass.Files {
for _, decl := range file.Decls {
w := maybePrintfWrapper(pass.TypesInfo, decl)
if w == nil {
continue
}
byObj[w.obj] = w
wrappers = append(wrappers, w)
}
}
// Walk the graph to figure out which are really printf wrappers.
for _, w := range wrappers {
// Scan function for calls that could be to other printf-like functions.
ast.Inspect(w.fdecl.Body, func(n ast.Node) bool {
if w.failed {
return false
}
// TODO: Relax these checks; issue 26555.
if assign, ok := n.(*ast.AssignStmt); ok {
for _, lhs := range assign.Lhs {
if match(pass.TypesInfo, lhs, w.format) ||
match(pass.TypesInfo, lhs, w.args) {
// Modifies the format
// string or args in
// some way, so not a
// simple wrapper.
w.failed = true
return false
}
}
}
if un, ok := n.(*ast.UnaryExpr); ok && un.Op == token.AND {
if match(pass.TypesInfo, un.X, w.format) ||
match(pass.TypesInfo, un.X, w.args) {
// Taking the address of the
// format string or args,
// so not a simple wrapper.
w.failed = true
return false
}
}
call, ok := n.(*ast.CallExpr)
if !ok || len(call.Args) == 0 || !match(pass.TypesInfo, call.Args[len(call.Args)-1], w.args) {
return true
}
fn, kind := printfNameAndKind(pass, call)
if kind != 0 {
checkPrintfFwd(pass, w, call, kind)
return true
}
// If the call is to another function in this package,
// maybe we will find out it is printf-like later.
// Remember this call for later checking.
if fn != nil && fn.Pkg() == pass.Pkg && byObj[fn] != nil {
callee := byObj[fn]
callee.callers = append(callee.callers, printfCaller{w, call})
}
return true
})
}
return nil, nil
}
func match(info *types.Info, arg ast.Expr, param *types.Var) bool {
id, ok := arg.(*ast.Ident)
return ok && info.ObjectOf(id) == param
}
const (
kindPrintf = 1
kindPrint = 2
)
// checkPrintfFwd checks that a printf-forwarding wrapper is forwarding correctly.
// It diagnoses writing fmt.Printf(format, args) instead of fmt.Printf(format, args...).
func checkPrintfFwd(pass *analysis.Pass, w *printfWrapper, call *ast.CallExpr, kind int) {
matched := kind == kindPrint ||
kind == kindPrintf && len(call.Args) >= 2 && match(pass.TypesInfo, call.Args[len(call.Args)-2], w.format)
if !matched {
return
}
if !call.Ellipsis.IsValid() {
typ, ok := pass.TypesInfo.Types[call.Fun].Type.(*types.Signature)
if !ok {
return
}
if len(call.Args) > typ.Params().Len() {
// If we're passing more arguments than what the
// print/printf function can take, adding an ellipsis
// would break the program. For example:
//
// func foo(arg1 string, arg2 ...interface{} {
// fmt.Printf("%s %v", arg1, arg2)
// }
return
}
desc := "printf"
if kind == kindPrint {
desc = "print"
}
pass.Reportf(call.Pos(), "missing ... in args forwarded to %s-like function", desc)
return
}
fn := w.obj
var fact isWrapper
if !pass.ImportObjectFact(fn, &fact) {
fact.Printf = kind == kindPrintf
pass.ExportObjectFact(fn, &fact)
for _, caller := range w.callers {
checkPrintfFwd(pass, caller.w, caller.call, kind)
}
}
}
// isPrint records the print functions.
// If a key ends in 'f' then it is assumed to be a formatted print.
//
// Keys are either values returned by (*types.Func).FullName,
// or case-insensitive identifiers such as "errorf".
//
// The -funcs flag adds to this set.
var isPrint = stringSet{
"fmt.Errorf": true,
"fmt.Fprint": true,
"fmt.Fprintf": true,
"fmt.Fprintln": true,
"fmt.Print": true, // technically these three
"fmt.Printf": true, // are redundant because they
"fmt.Println": true, // forward to Fprint{,f,ln}
"fmt.Sprint": true,
"fmt.Sprintf": true,
"fmt.Sprintln": true,
// *testing.T and B are detected by induction, but testing.TB is
// an interface and the inference can't follow dynamic calls.
"(testing.TB).Error": true,
"(testing.TB).Errorf": true,
"(testing.TB).Fatal": true,
"(testing.TB).Fatalf": true,
"(testing.TB).Log": true,
"(testing.TB).Logf": true,
"(testing.TB).Skip": true,
"(testing.TB).Skipf": true,
}
// formatString returns the format string argument and its index within
// the given printf-like call expression.
//
// The last parameter before variadic arguments is assumed to be
// a format string.
//
// The first string literal or string constant is assumed to be a format string
// if the call's signature cannot be determined.
//
// If it cannot find any format string parameter, it returns ("", -1).
func formatString(pass *analysis.Pass, call *ast.CallExpr) (format string, idx int) {
typ := pass.TypesInfo.Types[call.Fun].Type
if typ != nil {
if sig, ok := typ.(*types.Signature); ok {
if !sig.Variadic() {
// Skip checking non-variadic functions.
return "", -1
}
idx := sig.Params().Len() - 2
if idx < 0 {
// Skip checking variadic functions without
// fixed arguments.
return "", -1
}
s, ok := stringConstantArg(pass, call, idx)
if !ok {
// The last argument before variadic args isn't a string.
return "", -1
}
return s, idx
}
}
// Cannot determine call's signature. Fall back to scanning for the first
// string constant in the call.
for idx := range call.Args {
if s, ok := stringConstantArg(pass, call, idx); ok {
return s, idx
}
if pass.TypesInfo.Types[call.Args[idx]].Type == types.Typ[types.String] {
// Skip checking a call with a non-constant format
// string argument, since its contents are unavailable
// for validation.
return "", -1
}
}
return "", -1
}
// stringConstantArg returns call's string constant argument at the index idx.
//
// ("", false) is returned if call's argument at the index idx isn't a string
// constant.
func stringConstantArg(pass *analysis.Pass, call *ast.CallExpr, idx int) (string, bool) {
if idx >= len(call.Args) {
return "", false
}
arg := call.Args[idx]
lit := pass.TypesInfo.Types[arg].Value
if lit != nil && lit.Kind() == constant.String {
return constant.StringVal(lit), true
}
return "", false
}
// checkCall triggers the print-specific checks if the call invokes a print function.
func checkCall(pass *analysis.Pass) {
inspect := pass.ResultOf[inspect.Analyzer].(*inspector.Inspector)
nodeFilter := []ast.Node{
(*ast.CallExpr)(nil),
}
inspect.Preorder(nodeFilter, func(n ast.Node) {
call := n.(*ast.CallExpr)
fn, kind := printfNameAndKind(pass, call)
switch kind {
case kindPrintf:
checkPrintf(pass, call, fn)
case kindPrint:
checkPrint(pass, call, fn)
}
})
}
func printfNameAndKind(pass *analysis.Pass, call *ast.CallExpr) (fn *types.Func, kind int) {
fn, _ = typeutil.Callee(pass.TypesInfo, call).(*types.Func)
if fn == nil {
return nil, 0
}
var fact isWrapper
if pass.ImportObjectFact(fn, &fact) {
if fact.Printf {
return fn, kindPrintf
} else {
return fn, kindPrint
}
}
_, ok := isPrint[fn.FullName()]
if !ok {
// Next look up just "printf", for use with -printf.funcs.
_, ok = isPrint[strings.ToLower(fn.Name())]
}
if ok {
if strings.HasSuffix(fn.Name(), "f") {
kind = kindPrintf
} else {
kind = kindPrint
}
}
return fn, kind
}
// isFormatter reports whether t satisfies fmt.Formatter.
// Unlike fmt.Stringer, it's impossible to satisfy fmt.Formatter without importing fmt.
func isFormatter(pass *analysis.Pass, t types.Type) bool {
for _, imp := range pass.Pkg.Imports() {
if imp.Path() == "fmt" {
formatter := imp.Scope().Lookup("Formatter").Type().Underlying().(*types.Interface)
return types.Implements(t, formatter)
}
}
return false
}
// formatState holds the parsed representation of a printf directive such as "%3.*[4]d".
// It is constructed by parsePrintfVerb.
type formatState struct {
verb rune // the format verb: 'd' for "%d"
format string // the full format directive from % through verb, "%.3d".
name string // Printf, Sprintf etc.
flags []byte // the list of # + etc.
argNums []int // the successive argument numbers that are consumed, adjusted to refer to actual arg in call
firstArg int // Index of first argument after the format in the Printf call.
// Used only during parse.
pass *analysis.Pass
call *ast.CallExpr
argNum int // Which argument we're expecting to format now.
hasIndex bool // Whether the argument is indexed.
indexPending bool // Whether we have an indexed argument that has not resolved.
nbytes int // number of bytes of the format string consumed.
}
// checkPrintf checks a call to a formatted print routine such as Printf.
func checkPrintf(pass *analysis.Pass, call *ast.CallExpr, fn *types.Func) {
format, idx := formatString(pass, call)
if idx < 0 {
if false {
pass.Reportf(call.Lparen, "can't check non-constant format in call to %s", fn.Name())
}
return
}
firstArg := idx + 1 // Arguments are immediately after format string.
if !strings.Contains(format, "%") {
if len(call.Args) > firstArg {
pass.Reportf(call.Lparen, "%s call has arguments but no formatting directives", fn.Name())
}
return
}
// Hard part: check formats against args.
argNum := firstArg
maxArgNum := firstArg
anyIndex := false
for i, w := 0, 0; i < len(format); i += w {
w = 1
if format[i] != '%' {
continue
}
state := parsePrintfVerb(pass, call, fn.Name(), format[i:], firstArg, argNum)
if state == nil {
return
}
w = len(state.format)
if !okPrintfArg(pass, call, state) { // One error per format is enough.
return
}
if state.hasIndex {
anyIndex = true
}
if len(state.argNums) > 0 {
// Continue with the next sequential argument.
argNum = state.argNums[len(state.argNums)-1] + 1
}
for _, n := range state.argNums {
if n >= maxArgNum {
maxArgNum = n + 1
}
}
}
// Dotdotdot is hard.
if call.Ellipsis.IsValid() && maxArgNum >= len(call.Args)-1 {
return
}
// If any formats are indexed, extra arguments are ignored.
if anyIndex {
return
}
// There should be no leftover arguments.
if maxArgNum != len(call.Args) {
expect := maxArgNum - firstArg
numArgs := len(call.Args) - firstArg
pass.Reportf(call.Pos(), "%s call needs %v but has %v", fn.Name(), count(expect, "arg"), count(numArgs, "arg"))
}
}
// parseFlags accepts any printf flags.
func (s *formatState) parseFlags() {
for s.nbytes < len(s.format) {
switch c := s.format[s.nbytes]; c {
case '#', '0', '+', '-', ' ':
s.flags = append(s.flags, c)
s.nbytes++
default:
return
}
}
}
// scanNum advances through a decimal number if present.
func (s *formatState) scanNum() {
for ; s.nbytes < len(s.format); s.nbytes++ {
c := s.format[s.nbytes]
if c < '0' || '9' < c {
return
}
}
}
// parseIndex scans an index expression. It returns false if there is a syntax error.
func (s *formatState) parseIndex() bool {
if s.nbytes == len(s.format) || s.format[s.nbytes] != '[' {
return true
}
// Argument index present.
s.nbytes++ // skip '['
start := s.nbytes
s.scanNum()
ok := true
if s.nbytes == len(s.format) || s.nbytes == start || s.format[s.nbytes] != ']' {
ok = false
s.nbytes = strings.Index(s.format, "]")
if s.nbytes < 0 {
s.pass.Reportf(s.call.Pos(), "%s format %s is missing closing ]", s.name, s.format)
return false
}
}
arg32, err := strconv.ParseInt(s.format[start:s.nbytes], 10, 32)
if err != nil || !ok || arg32 <= 0 || arg32 > int64(len(s.call.Args)-s.firstArg) {
s.pass.Reportf(s.call.Pos(), "%s format has invalid argument index [%s]", s.name, s.format[start:s.nbytes])
return false
}
s.nbytes++ // skip ']'
arg := int(arg32)
arg += s.firstArg - 1 // We want to zero-index the actual arguments.
s.argNum = arg
s.hasIndex = true
s.indexPending = true
return true
}
// parseNum scans a width or precision (or *). It returns false if there's a bad index expression.
func (s *formatState) parseNum() bool {
if s.nbytes < len(s.format) && s.format[s.nbytes] == '*' {
if s.indexPending { // Absorb it.
s.indexPending = false
}
s.nbytes++
s.argNums = append(s.argNums, s.argNum)
s.argNum++
} else {
s.scanNum()
}
return true
}
// parsePrecision scans for a precision. It returns false if there's a bad index expression.
func (s *formatState) parsePrecision() bool {
// If there's a period, there may be a precision.
if s.nbytes < len(s.format) && s.format[s.nbytes] == '.' {
s.flags = append(s.flags, '.') // Treat precision as a flag.
s.nbytes++
if !s.parseIndex() {
return false
}
if !s.parseNum() {
return false
}
}
return true
}
// parsePrintfVerb looks the formatting directive that begins the format string
// and returns a formatState that encodes what the directive wants, without looking
// at the actual arguments present in the call. The result is nil if there is an error.
func parsePrintfVerb(pass *analysis.Pass, call *ast.CallExpr, name, format string, firstArg, argNum int) *formatState {
state := &formatState{
format: format,
name: name,
flags: make([]byte, 0, 5),
argNum: argNum,
argNums: make([]int, 0, 1),
nbytes: 1, // There's guaranteed to be a percent sign.
firstArg: firstArg,
pass: pass,
call: call,
}
// There may be flags.
state.parseFlags()
// There may be an index.
if !state.parseIndex() {
return nil
}
// There may be a width.
if !state.parseNum() {
return nil
}
// There may be a precision.
if !state.parsePrecision() {
return nil
}
// Now a verb, possibly prefixed by an index (which we may already have).
if !state.indexPending && !state.parseIndex() {
return nil
}
if state.nbytes == len(state.format) {
pass.Reportf(call.Pos(), "%s format %s is missing verb at end of string", name, state.format)
return nil
}
verb, w := utf8.DecodeRuneInString(state.format[state.nbytes:])
state.verb = verb
state.nbytes += w
if verb != '%' {
state.argNums = append(state.argNums, state.argNum)
}
state.format = state.format[:state.nbytes]
return state
}
// printfArgType encodes the types of expressions a printf verb accepts. It is a bitmask.
type printfArgType int
const (
argBool printfArgType = 1 << iota
argInt
argRune
argString
argFloat
argComplex
argPointer
anyType printfArgType = ^0
)
type printVerb struct {
verb rune // User may provide verb through Formatter; could be a rune.
flags string // known flags are all ASCII
typ printfArgType
}
// Common flag sets for printf verbs.
const (
noFlag = ""
numFlag = " -+.0"
sharpNumFlag = " -+.0#"
allFlags = " -+.0#"
)
// printVerbs identifies which flags are known to printf for each verb.
var printVerbs = []printVerb{
// '-' is a width modifier, always valid.
// '.' is a precision for float, max width for strings.
// '+' is required sign for numbers, Go format for %v.
// '#' is alternate format for several verbs.
// ' ' is spacer for numbers
{'%', noFlag, 0},
{'b', numFlag, argInt | argFloat | argComplex},
{'c', "-", argRune | argInt},
{'d', numFlag, argInt | argPointer},
{'e', sharpNumFlag, argFloat | argComplex},
{'E', sharpNumFlag, argFloat | argComplex},
{'f', sharpNumFlag, argFloat | argComplex},
{'F', sharpNumFlag, argFloat | argComplex},
{'g', sharpNumFlag, argFloat | argComplex},
{'G', sharpNumFlag, argFloat | argComplex},
{'o', sharpNumFlag, argInt},
{'p', "-#", argPointer},
{'q', " -+.0#", argRune | argInt | argString},
{'s', " -+.0", argString},
{'t', "-", argBool},
{'T', "-", anyType},
{'U', "-#", argRune | argInt},
{'v', allFlags, anyType},
{'x', sharpNumFlag, argRune | argInt | argString | argPointer},
{'X', sharpNumFlag, argRune | argInt | argString | argPointer},
}
// okPrintfArg compares the formatState to the arguments actually present,
// reporting any discrepancies it can discern. If the final argument is ellipsissed,
// there's little it can do for that.
func okPrintfArg(pass *analysis.Pass, call *ast.CallExpr, state *formatState) (ok bool) {
var v printVerb
found := false
// Linear scan is fast enough for a small list.
for _, v = range printVerbs {
if v.verb == state.verb {
found = true
break
}
}
// Does current arg implement fmt.Formatter?
formatter := false
if state.argNum < len(call.Args) {
if tv, ok := pass.TypesInfo.Types[call.Args[state.argNum]]; ok {
formatter = isFormatter(pass, tv.Type)
}
}
if !formatter {
if !found {
pass.Reportf(call.Pos(), "%s format %s has unknown verb %c", state.name, state.format, state.verb)
return false
}
for _, flag := range state.flags {
// TODO: Disable complaint about '0' for Go 1.10. To be fixed properly in 1.11.
// See issues 23598 and 23605.
if flag == '0' {
continue
}
if !strings.ContainsRune(v.flags, rune(flag)) {
pass.Reportf(call.Pos(), "%s format %s has unrecognized flag %c", state.name, state.format, flag)
return false
}
}
}
// Verb is good. If len(state.argNums)>trueArgs, we have something like %.*s and all
// but the final arg must be an integer.
trueArgs := 1
if state.verb == '%' {
trueArgs = 0
}
nargs := len(state.argNums)
for i := 0; i < nargs-trueArgs; i++ {
argNum := state.argNums[i]
if !argCanBeChecked(pass, call, i, state) {
return
}
arg := call.Args[argNum]
if !matchArgType(pass, argInt, nil, arg) {
pass.Reportf(call.Pos(), "%s format %s uses non-int %s as argument of *", state.name, state.format, analysisutil.Format(pass.Fset, arg))
return false
}
}
if state.verb == '%' || formatter {
return true
}
argNum := state.argNums[len(state.argNums)-1]
if !argCanBeChecked(pass, call, len(state.argNums)-1, state) {
return false
}
arg := call.Args[argNum]
if isFunctionValue(pass, arg) && state.verb != 'p' && state.verb != 'T' {
pass.Reportf(call.Pos(), "%s format %s arg %s is a func value, not called", state.name, state.format, analysisutil.Format(pass.Fset, arg))
return false
}
if !matchArgType(pass, v.typ, nil, arg) {
typeString := ""
if typ := pass.TypesInfo.Types[arg].Type; typ != nil {
typeString = typ.String()
}
pass.Reportf(call.Pos(), "%s format %s has arg %s of wrong type %s", state.name, state.format, analysisutil.Format(pass.Fset, arg), typeString)
return false
}
if v.typ&argString != 0 && v.verb != 'T' && !bytes.Contains(state.flags, []byte{'#'}) && recursiveStringer(pass, arg) {
pass.Reportf(call.Pos(), "%s format %s with arg %s causes recursive String method call", state.name, state.format, analysisutil.Format(pass.Fset, arg))
return false
}
return true
}
// recursiveStringer reports whether the argument e is a potential
// recursive call to stringer, such as t and &t in these examples:
//
// func (t *T) String() string { printf("%s", t) }
// func (t T) String() string { printf("%s", t) }
// func (t T) String() string { printf("%s", &t) }
//
func recursiveStringer(pass *analysis.Pass, e ast.Expr) bool {
typ := pass.TypesInfo.Types[e].Type
// It's unlikely to be a recursive stringer if it has a Format method.
if isFormatter(pass, typ) {
return false
}
// Does e allow e.String()?
obj, _, _ := types.LookupFieldOrMethod(typ, false, pass.Pkg, "String")
stringMethod, ok := obj.(*types.Func)
if !ok {
return false
}
// Is the expression e within the body of that String method?
return stringMethod.Pkg() == pass.Pkg && stringMethod.Scope().Contains(e.Pos())
}
// isFunctionValue reports whether the expression is a function as opposed to a function call.
// It is almost always a mistake to print a function value.
func isFunctionValue(pass *analysis.Pass, e ast.Expr) bool {
if typ := pass.TypesInfo.Types[e].Type; typ != nil {
_, ok := typ.(*types.Signature)
return ok
}
return false
}
// argCanBeChecked reports whether the specified argument is statically present;
// it may be beyond the list of arguments or in a terminal slice... argument, which
// means we can't see it.
func argCanBeChecked(pass *analysis.Pass, call *ast.CallExpr, formatArg int, state *formatState) bool {
argNum := state.argNums[formatArg]
if argNum <= 0 {
// Shouldn't happen, so catch it with prejudice.
panic("negative arg num")
}
if argNum < len(call.Args)-1 {
return true // Always OK.
}
if call.Ellipsis.IsValid() {
return false // We just can't tell; there could be many more arguments.
}
if argNum < len(call.Args) {
return true
}
// There are bad indexes in the format or there are fewer arguments than the format needs.
// This is the argument number relative to the format: Printf("%s", "hi") will give 1 for the "hi".
arg := argNum - state.firstArg + 1 // People think of arguments as 1-indexed.
pass.Reportf(call.Pos(), "%s format %s reads arg #%d, but call has %v", state.name, state.format, arg, count(len(call.Args)-state.firstArg, "arg"))
return false
}
// printFormatRE is the regexp we match and report as a possible format string
// in the first argument to unformatted prints like fmt.Print.
// We exclude the space flag, so that printing a string like "x % y" is not reported as a format.
var printFormatRE = regexp.MustCompile(`%` + flagsRE + numOptRE + `\.?` + numOptRE + indexOptRE + verbRE)
const (
flagsRE = `[+\-#]*`
indexOptRE = `(\[[0-9]+\])?`
numOptRE = `([0-9]+|` + indexOptRE + `\*)?`
verbRE = `[bcdefgopqstvxEFGTUX]`
)
// checkPrint checks a call to an unformatted print routine such as Println.
func checkPrint(pass *analysis.Pass, call *ast.CallExpr, fn *types.Func) {
firstArg := 0
typ := pass.TypesInfo.Types[call.Fun].Type
if typ == nil {
// Skip checking functions with unknown type.
return
}
if sig, ok := typ.(*types.Signature); ok {
if !sig.Variadic() {
// Skip checking non-variadic functions.
return
}
params := sig.Params()
firstArg = params.Len() - 1
typ := params.At(firstArg).Type()
typ = typ.(*types.Slice).Elem()
it, ok := typ.(*types.Interface)
if !ok || !it.Empty() {
// Skip variadic functions accepting non-interface{} args.
return
}
}
args := call.Args
if len(args) <= firstArg {
// Skip calls without variadic args.
return
}
args = args[firstArg:]
if firstArg == 0 {
if sel, ok := call.Args[0].(*ast.SelectorExpr); ok {
if x, ok := sel.X.(*ast.Ident); ok {
if x.Name == "os" && strings.HasPrefix(sel.Sel.Name, "Std") {
pass.Reportf(call.Pos(), "%s does not take io.Writer but has first arg %s", fn.Name(), analysisutil.Format(pass.Fset, call.Args[0]))
}
}
}
}
arg := args[0]
if lit, ok := arg.(*ast.BasicLit); ok && lit.Kind == token.STRING {
// Ignore trailing % character in lit.Value.
// The % in "abc 0.0%" couldn't be a formatting directive.
s := strings.TrimSuffix(lit.Value, `%"`)
if strings.Contains(s, "%") {
m := printFormatRE.FindStringSubmatch(s)
if m != nil {
pass.Reportf(call.Pos(), "%s call has possible formatting directive %s", fn.Name(), m[0])
}
}
}
if strings.HasSuffix(fn.Name(), "ln") {
// The last item, if a string, should not have a newline.
arg = args[len(args)-1]
if lit, ok := arg.(*ast.BasicLit); ok && lit.Kind == token.STRING {
str, _ := strconv.Unquote(lit.Value)
if strings.HasSuffix(str, "\n") {
pass.Reportf(call.Pos(), "%s arg list ends with redundant newline", fn.Name())
}
}
}
for _, arg := range args {
if isFunctionValue(pass, arg) {
pass.Reportf(call.Pos(), "%s arg %s is a func value, not called", fn.Name(), analysisutil.Format(pass.Fset, arg))
}
if recursiveStringer(pass, arg) {
pass.Reportf(call.Pos(), "%s arg %s causes recursive call to String method", fn.Name(), analysisutil.Format(pass.Fset, arg))
}
}
}
// count(n, what) returns "1 what" or "N whats"
// (assuming the plural of what is whats).
func count(n int, what string) string {
if n == 1 {
return "1 " + what
}
return fmt.Sprintf("%d %ss", n, what)
}
// stringSet is a set-of-nonempty-strings-valued flag.
// Note: elements without a '.' get lower-cased.
type stringSet map[string]bool
func (ss stringSet) String() string {
var list []string
for name := range ss {
list = append(list, name)
}
sort.Strings(list)
return strings.Join(list, ",")
}
func (ss stringSet) Set(flag string) error {
for _, name := range strings.Split(flag, ",") {
if len(name) == 0 {
return fmt.Errorf("empty string")
}
if !strings.Contains(name, ".") {
name = strings.ToLower(name)
}
ss[name] = true
}
return nil
}
src/cmd/vendor/golang.org/x/tools/go/analysis/passes/printf/types.go 0 → 100644
View file @ 8b469209
package printf
import (
"go/ast"
"go/build"
"go/types"
"golang.org/x/tools/go/analysis"
"golang.org/x/tools/go/analysis/passes/internal/analysisutil"
)
var errorType = types.Universe.Lookup("error").Type().Underlying().(*types.Interface)
// matchArgType reports an error if printf verb t is not appropriate
// for operand arg.
//
// typ is used only for recursive calls; external callers must supply nil.
//
// (Recursion arises from the compound types {map,chan,slice} which
// may be printed with %d etc. if that is appropriate for their element
// types.)
func matchArgType(pass *analysis.Pass, t printfArgType, typ types.Type, arg ast.Expr) bool {
return matchArgTypeInternal(pass, t, typ, arg, make(map[types.Type]bool))
}
// matchArgTypeInternal is the internal version of matchArgType. It carries a map
// remembering what types are in progress so we don't recur when faced with recursive
// types or mutually recursive types.
func matchArgTypeInternal(pass *analysis.Pass, t printfArgType, typ types.Type, arg ast.Expr, inProgress map[types.Type]bool) bool {
// %v, %T accept any argument type.
if t == anyType {
return true
}
if typ == nil {
// external call
typ = pass.TypesInfo.Types[arg].Type
if typ == nil {
return true // probably a type check problem
}
}
// If the type implements fmt.Formatter, we have nothing to check.
if isFormatter(pass, typ) {
return true
}
// If we can use a string, might arg (dynamically) implement the Stringer or Error interface?
if t&argString != 0 && isConvertibleToString(pass, typ) {
return true
}
typ = typ.Underlying()
if inProgress[typ] {
// We're already looking at this type. The call that started it will take care of it.
return true
}
inProgress[typ] = true
switch typ := typ.(type) {
case *types.Signature:
return t&argPointer != 0
case *types.Map:
// Recur: map[int]int matches %d.
return t&argPointer != 0 ||
(matchArgTypeInternal(pass, t, typ.Key(), arg, inProgress) && matchArgTypeInternal(pass, t, typ.Elem(), arg, inProgress))
case *types.Chan:
return t&argPointer != 0
case *types.Array:
// Same as slice.
if types.Identical(typ.Elem().Underlying(), types.Typ[types.Byte]) && t&argString != 0 {
return true // %s matches []byte
}
// Recur: []int matches %d.
return t&argPointer != 0 || matchArgTypeInternal(pass, t, typ.Elem(), arg, inProgress)
case *types.Slice:
// Same as array.
if types.Identical(typ.Elem().Underlying(), types.Typ[types.Byte]) && t&argString != 0 {
return true // %s matches []byte
}
// Recur: []int matches %d. But watch out for
// type T []T
// If the element is a pointer type (type T[]*T), it's handled fine by the Pointer case below.
return t&argPointer != 0 || matchArgTypeInternal(pass, t, typ.Elem(), arg, inProgress)
case *types.Pointer:
// Ugly, but dealing with an edge case: a known pointer to an invalid type,
// probably something from a failed import.
if typ.Elem().String() == "invalid type" {
if false {
pass.Reportf(arg.Pos(), "printf argument %v is pointer to invalid or unknown type", analysisutil.Format(pass.Fset, arg))
}
return true // special case
}
// If it's actually a pointer with %p, it prints as one.
if t == argPointer {
return true
}
// If it's pointer to struct, that's equivalent in our analysis to whether we can print the struct.
if str, ok := typ.Elem().Underlying().(*types.Struct); ok {
return matchStructArgType(pass, t, str, arg, inProgress)
}
// Check whether the rest can print pointers.
return t&argPointer != 0
case *types.Struct:
return matchStructArgType(pass, t, typ, arg, inProgress)
case *types.Interface:
// There's little we can do.
// Whether any particular verb is valid depends on the argument.
// The user may have reasonable prior knowledge of the contents of the interface.
return true
case *types.Basic:
switch typ.Kind() {
case types.UntypedBool,
types.Bool:
return t&argBool != 0
case types.UntypedInt,
types.Int,
types.Int8,
types.Int16,
types.Int32,
types.Int64,
types.Uint,
types.Uint8,
types.Uint16,
types.Uint32,
types.Uint64,
types.Uintptr:
return t&argInt != 0
case types.UntypedFloat,
types.Float32,
types.Float64:
return t&argFloat != 0
case types.UntypedComplex,
types.Complex64,
types.Complex128:
return t&argComplex != 0
case types.UntypedString,
types.String:
return t&argString != 0
case types.UnsafePointer:
return t&(argPointer|argInt) != 0
case types.UntypedRune:
return t&(argInt|argRune) != 0
case types.UntypedNil:
return false
case types.Invalid:
if false {
pass.Reportf(arg.Pos(), "printf argument %v has invalid or unknown type", analysisutil.Format(pass.Fset, arg))
}
return true // Probably a type check problem.
}
panic("unreachable")
}
return false
}
func isConvertibleToString(pass *analysis.Pass, typ types.Type) bool {
if bt, ok := typ.(*types.Basic); ok && bt.Kind() == types.UntypedNil {
// We explicitly don't want untyped nil, which is
// convertible to both of the interfaces below, as it
// would just panic anyway.
return false
}
if types.ConvertibleTo(typ, errorType) {
return true // via .Error()
}
// Does it implement fmt.Stringer?
if obj, _, _ := types.LookupFieldOrMethod(typ, false, nil, "String"); obj != nil {
if fn, ok := obj.(*types.Func); ok {
sig := fn.Type().(*types.Signature)
if sig.Params().Len() == 0 &&
sig.Results().Len() == 1 &&
sig.Results().At(0).Type() == types.Typ[types.String] {
return true
}
}
}
return false
}
// hasBasicType reports whether x's type is a types.Basic with the given kind.
func hasBasicType(pass *analysis.Pass, x ast.Expr, kind types.BasicKind) bool {
t := pass.TypesInfo.Types[x].Type
if t != nil {
t = t.Underlying()
}
b, ok := t.(*types.Basic)
return ok && b.Kind() == kind
}
// matchStructArgType reports whether all the elements of the struct match the expected
// type. For instance, with "%d" all the elements must be printable with the "%d" format.
func matchStructArgType(pass *analysis.Pass, t printfArgType, typ *types.Struct, arg ast.Expr, inProgress map[types.Type]bool) bool {
for i := 0; i < typ.NumFields(); i++ {
typf := typ.Field(i)
if !matchArgTypeInternal(pass, t, typf.Type(), arg, inProgress) {
return false
}
if t&argString != 0 && !typf.Exported() && isConvertibleToString(pass, typf.Type()) {
// Issue #17798: unexported Stringer or error cannot be properly fomatted.
return false
}
}
return true
}
var archSizes = types.SizesFor("gc", build.Default.GOARCH)
src/cmd/vendor/golang.org/x/tools/go/analysis/passes/shift/dead.go 0 → 100644
View file @ 8b469209
// Copyright 2017 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
package shift
// Simplified dead code detector.
// Used for skipping shift checks on unreachable arch-specific code.
import (
"go/ast"
"go/constant"
"go/types"
)
// updateDead puts unreachable "if" and "case" nodes into dead.
func updateDead(info *types.Info, dead map[ast.Node]bool, node ast.Node) {
if dead[node] {
// The node is already marked as dead.
return
}
// setDead marks the node and all the children as dead.
setDead := func(n ast.Node) {
ast.Inspect(n, func(node ast.Node) bool {
if node != nil {
dead[node] = true
}
return true
})
}
switch stmt := node.(type) {
case *ast.IfStmt:
// "if" branch is dead if its condition evaluates
// to constant false.
v := info.Types[stmt.Cond].Value
if v == nil {
return
}
if !constant.BoolVal(v) {
setDead(stmt.Body)
return
}
if stmt.Else != nil {
setDead(stmt.Else)
}
case *ast.SwitchStmt:
// Case clause with empty switch tag is dead if it evaluates
// to constant false.
if stmt.Tag == nil {
BodyLoopBool:
for _, stmt := range stmt.Body.List {
cc := stmt.(*ast.CaseClause)
if cc.List == nil {
// Skip default case.
continue
}
for _, expr := range cc.List {
v := info.Types[expr].Value
if v == nil || v.Kind() != constant.Bool || constant.BoolVal(v) {
continue BodyLoopBool
}
}
setDead(cc)
}
return
}
// Case clause is dead if its constant value doesn't match
// the constant value from the switch tag.
// TODO: This handles integer comparisons only.
v := info.Types[stmt.Tag].Value
if v == nil || v.Kind() != constant.Int {
return
}
tagN, ok := constant.Uint64Val(v)
if !ok {
return
}
BodyLoopInt:
for _, x := range stmt.Body.List {
cc := x.(*ast.CaseClause)
if cc.List == nil {
// Skip default case.
continue
}
for _, expr := range cc.List {
v := info.Types[expr].Value
if v == nil {
continue BodyLoopInt
}
n, ok := constant.Uint64Val(v)
if !ok || tagN == n {
continue BodyLoopInt
}
}
setDead(cc)
}
}
}
src/cmd/vendor/golang.org/x/tools/go/analysis/passes/shift/shift.go 0 → 100644
View file @ 8b469209
// Copyright 2014 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
// Package shift defines an Analyzer that checks for shifts that exceed
// the width of an integer.
package shift
// TODO(adonovan): integrate with ctrflow (CFG-based) dead code analysis. May
// have impedance mismatch due to its (non-)treatment of constant
// expressions (such as runtime.GOARCH=="386").
import (
"go/ast"
"go/build"
"go/constant"
"go/token"
"go/types"
"golang.org/x/tools/go/analysis"
"golang.org/x/tools/go/analysis/passes/inspect"
"golang.org/x/tools/go/analysis/passes/internal/analysisutil"
"golang.org/x/tools/go/ast/inspector"
)
var Analyzer = &analysis.Analyzer{
Name: "shift",
Doc: "check for shifts that equal or exceed the width of the integer",
Requires: []*analysis.Analyzer{inspect.Analyzer},
Run: run,
}
func run(pass *analysis.Pass) (interface{}, error) {
inspect := pass.ResultOf[inspect.Analyzer].(*inspector.Inspector)
// Do a complete pass to compute dead nodes.
dead := make(map[ast.Node]bool)
nodeFilter := []ast.Node{
(*ast.IfStmt)(nil),
(*ast.SwitchStmt)(nil),
}
inspect.Preorder(nodeFilter, func(n ast.Node) {
// TODO(adonovan): move updateDead into this file.
updateDead(pass.TypesInfo, dead, n)
})
nodeFilter = []ast.Node{
(*ast.AssignStmt)(nil),
(*ast.BinaryExpr)(nil),
}
inspect.Preorder(nodeFilter, func(node ast.Node) {
if dead[node] {
// Skip shift checks on unreachable nodes.
return
}
switch node := node.(type) {
case *ast.BinaryExpr:
if node.Op == token.SHL || node.Op == token.SHR {
checkLongShift(pass, node, node.X, node.Y)
}
case *ast.AssignStmt:
if len(node.Lhs) != 1 || len(node.Rhs) != 1 {
return
}
if node.Tok == token.SHL_ASSIGN || node.Tok == token.SHR_ASSIGN {
checkLongShift(pass, node, node.Lhs[0], node.Rhs[0])
}
}
})
return nil, nil
}
// checkLongShift checks if shift or shift-assign operations shift by more than
// the length of the underlying variable.
func checkLongShift(pass *analysis.Pass, node ast.Node, x, y ast.Expr) {
if pass.TypesInfo.Types[x].Value != nil {
// Ignore shifts of constants.
// These are frequently used for bit-twiddling tricks
// like ^uint(0) >> 63 for 32/64 bit detection and compatibility.
return
}
v := pass.TypesInfo.Types[y].Value
if v == nil {
return
}
amt, ok := constant.Int64Val(v)
if !ok {
return
}
t := pass.TypesInfo.Types[x].Type
if t == nil {
return
}
b, ok := t.Underlying().(*types.Basic)
if !ok {
return
}
var size int64
switch b.Kind() {
case types.Uint8, types.Int8:
size = 8
case types.Uint16, types.Int16:
size = 16
case types.Uint32, types.Int32:
size = 32
case types.Uint64, types.Int64:
size = 64
case types.Int, types.Uint:
size = uintBitSize
case types.Uintptr:
size = uintptrBitSize
default:
return
}
if amt >= size {
ident := analysisutil.Format(pass.Fset, x)
pass.Reportf(node.Pos(), "%s (%d bits) too small for shift of %d", ident, size, amt)
}
}
var (
uintBitSize = 8 * archSizes.Sizeof(types.Typ[types.Uint])
uintptrBitSize = 8 * archSizes.Sizeof(types.Typ[types.Uintptr])
)
var archSizes = types.SizesFor("gc", build.Default.GOARCH)
src/cmd/vendor/golang.org/x/tools/go/analysis/passes/stdmethods/stdmethods.go 0 → 100644
View file @ 8b469209
// Copyright 2010 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
// Package stdmethods defines an Analyzer that checks for misspellings
// in the signatures of methods similar to well-known interfaces.
package stdmethods
import (
"bytes"
"fmt"
"go/ast"
"go/printer"
"go/token"
"go/types"
"strings"
"golang.org/x/tools/go/analysis"
"golang.org/x/tools/go/analysis/passes/inspect"
"golang.org/x/tools/go/ast/inspector"
)
const Doc = `check signature of methods of well-known interfaces
Sometimes a type may be intended to satisfy an interface but may fail to
do so because of a mistake in its method signature.
For example, the result of this WriteTo method should be (int64, error),
not error, to satisfy io.WriterTo:
type myWriterTo struct{...}
func (myWriterTo) WriteTo(w io.Writer) error { ... }
This check ensures that each method whose name matches one of several
well-known interface methods from the standard library has the correct
signature for that interface.
Checked method names include:
Format GobEncode GobDecode MarshalJSON MarshalXML
Peek ReadByte ReadFrom ReadRune Scan Seek
UnmarshalJSON UnreadByte UnreadRune WriteByte
WriteTo
`
var Analyzer = &analysis.Analyzer{
Name: "stdmethods",
Doc: Doc,
Requires: []*analysis.Analyzer{inspect.Analyzer},
Run: run,
}
// canonicalMethods lists the input and output types for Go methods
// that are checked using dynamic interface checks. Because the
// checks are dynamic, such methods would not cause a compile error
// if they have the wrong signature: instead the dynamic check would
// fail, sometimes mysteriously. If a method is found with a name listed
// here but not the input/output types listed here, vet complains.
//
// A few of the canonical methods have very common names.
// For example, a type might implement a Scan method that
// has nothing to do with fmt.Scanner, but we still want to check
// the methods that are intended to implement fmt.Scanner.
// To do that, the arguments that have a = prefix are treated as
// signals that the canonical meaning is intended: if a Scan
// method doesn't have a fmt.ScanState as its first argument,
// we let it go. But if it does have a fmt.ScanState, then the
// rest has to match.
var canonicalMethods = map[string]struct{ args, results []string }{
// "Flush": {{}, {"error"}}, // http.Flusher and jpeg.writer conflict
"Format": {[]string{"=fmt.State", "rune"}, []string{}}, // fmt.Formatter
"GobDecode": {[]string{"[]byte"}, []string{"error"}}, // gob.GobDecoder
"GobEncode": {[]string{}, []string{"[]byte", "error"}}, // gob.GobEncoder
"MarshalJSON": {[]string{}, []string{"[]byte", "error"}}, // json.Marshaler
"MarshalXML": {[]string{"*xml.Encoder", "xml.StartElement"}, []string{"error"}}, // xml.Marshaler
"ReadByte": {[]string{}, []string{"byte", "error"}}, // io.ByteReader
"ReadFrom": {[]string{"=io.Reader"}, []string{"int64", "error"}}, // io.ReaderFrom
"ReadRune": {[]string{}, []string{"rune", "int", "error"}}, // io.RuneReader
"Scan": {[]string{"=fmt.ScanState", "rune"}, []string{"error"}}, // fmt.Scanner
"Seek": {[]string{"=int64", "int"}, []string{"int64", "error"}}, // io.Seeker
"UnmarshalJSON": {[]string{"[]byte"}, []string{"error"}}, // json.Unmarshaler
"UnmarshalXML": {[]string{"*xml.Decoder", "xml.StartElement"}, []string{"error"}}, // xml.Unmarshaler
"UnreadByte": {[]string{}, []string{"error"}},
"UnreadRune": {[]string{}, []string{"error"}},
"WriteByte": {[]string{"byte"}, []string{"error"}}, // jpeg.writer (matching bufio.Writer)
"WriteTo": {[]string{"=io.Writer"}, []string{"int64", "error"}}, // io.WriterTo
}
func run(pass *analysis.Pass) (interface{}, error) {
inspect := pass.ResultOf[inspect.Analyzer].(*inspector.Inspector)
nodeFilter := []ast.Node{
(*ast.FuncDecl)(nil),
(*ast.InterfaceType)(nil),
}
inspect.Preorder(nodeFilter, func(n ast.Node) {
switch n := n.(type) {
case *ast.FuncDecl:
if n.Recv != nil {
canonicalMethod(pass, n.Name, n.Type)
}
case *ast.InterfaceType:
for _, field := range n.Methods.List {
for _, id := range field.Names {
canonicalMethod(pass, id, field.Type.(*ast.FuncType))
}
}
}
})
return nil, nil
}
func canonicalMethod(pass *analysis.Pass, id *ast.Ident, t *ast.FuncType) {
// Expected input/output.
expect, ok := canonicalMethods[id.Name]
if !ok {
return
}
// Actual input/output
args := typeFlatten(t.Params.List)
var results []ast.Expr
if t.Results != nil {
results = typeFlatten(t.Results.List)
}
// Do the =s (if any) all match?
if !matchParams(pass, expect.args, args, "=") || !matchParams(pass, expect.results, results, "=") {
return
}
// Everything must match.
if !matchParams(pass, expect.args, args, "") || !matchParams(pass, expect.results, results, "") {
expectFmt := id.Name + "(" + argjoin(expect.args) + ")"
if len(expect.results) == 1 {
expectFmt += " " + argjoin(expect.results)
} else if len(expect.results) > 1 {
expectFmt += " (" + argjoin(expect.results) + ")"
}
var buf bytes.Buffer
if err := printer.Fprint(&buf, pass.Fset, t); err != nil {
fmt.Fprintf(&buf, "<%s>", err)
}
actual := buf.String()
actual = strings.TrimPrefix(actual, "func")
actual = id.Name + actual
pass.Reportf(id.Pos(), "method %s should have signature %s", actual, expectFmt)
}
}
func argjoin(x []string) string {
y := make([]string, len(x))
for i, s := range x {
if s[0] == '=' {
s = s[1:]
}
y[i] = s
}
return strings.Join(y, ", ")
}
// Turn parameter list into slice of types
// (in the ast, types are Exprs).
// Have to handle f(int, bool) and f(x, y, z int)
// so not a simple 1-to-1 conversion.
func typeFlatten(l []*ast.Field) []ast.Expr {
var t []ast.Expr
for _, f := range l {
if len(f.Names) == 0 {
t = append(t, f.Type)
continue
}
for range f.Names {
t = append(t, f.Type)
}
}
return t
}
// Does each type in expect with the given prefix match the corresponding type in actual?
func matchParams(pass *analysis.Pass, expect []string, actual []ast.Expr, prefix string) bool {
for i, x := range expect {
if !strings.HasPrefix(x, prefix) {
continue
}
if i >= len(actual) {
return false
}
if !matchParamType(pass.Fset, pass.Pkg, x, actual[i]) {
return false
}
}
if prefix == "" && len(actual) > len(expect) {
return false
}
return true
}
// Does this one type match?
func matchParamType(fset *token.FileSet, pkg *types.Package, expect string, actual ast.Expr) bool {
expect = strings.TrimPrefix(expect, "=")
// Strip package name if we're in that package.
if n := len(pkg.Name()); len(expect) > n && expect[:n] == pkg.Name() && expect[n] == '.' {
expect = expect[n+1:]
}
// Overkill but easy.
var buf bytes.Buffer
printer.Fprint(&buf, fset, actual)
return buf.String() == expect
}
src/cmd/vendor/golang.org/x/tools/go/analysis/passes/structtag/structtag.go 0 → 100644
View file @ 8b469209
// Copyright 2010 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
// Package structtag defines an Analyzer that checks struct field tags
// are well formed.
package structtag
import (
"errors"
"go/ast"
"go/token"
"go/types"
"path/filepath"
"reflect"
"strconv"
"strings"
"golang.org/x/tools/go/analysis"
"golang.org/x/tools/go/analysis/passes/inspect"
"golang.org/x/tools/go/ast/inspector"
)
const Doc = `check that struct field tags conform to reflect.StructTag.Get
Also report certain struct tags (json, xml) used with unexported fields.`
var Analyzer = &analysis.Analyzer{
Name: "structtag",
Doc: Doc,
Requires: []*analysis.Analyzer{inspect.Analyzer},
RunDespiteErrors: true,
Run: run,
}
func run(pass *analysis.Pass) (interface{}, error) {
inspect := pass.ResultOf[inspect.Analyzer].(*inspector.Inspector)
nodeFilter := []ast.Node{
(*ast.StructType)(nil),
}
inspect.Preorder(nodeFilter, func(n ast.Node) {
styp := pass.TypesInfo.Types[n.(*ast.StructType)].Type.(*types.Struct)
var seen map[[2]string]token.Pos
for i := 0; i < styp.NumFields(); i++ {
field := styp.Field(i)
tag := styp.Tag(i)
checkCanonicalFieldTag(pass, field, tag, &seen)
}
})
return nil, nil
}
var checkTagDups = []string{"json", "xml"}
var checkTagSpaces = map[string]bool{"json": true, "xml": true, "asn1": true}
// checkCanonicalFieldTag checks a single struct field tag.
func checkCanonicalFieldTag(pass *analysis.Pass, field *types.Var, tag string, seen *map[[2]string]token.Pos) {
for _, key := range checkTagDups {
checkTagDuplicates(pass, tag, key, field, field, seen)
}
if err := validateStructTag(tag); err != nil {
pass.Reportf(field.Pos(), "struct field tag %#q not compatible with reflect.StructTag.Get: %s", tag, err)
}
// Check for use of json or xml tags with unexported fields.
// Embedded struct. Nothing to do for now, but that
// may change, depending on what happens with issue 7363.
// TODO(adonovan): investigate, now that that issue is fixed.
if field.Anonymous() {
return
}
if field.Exported() {
return
}
for _, enc := range [...]string{"json", "xml"} {
if reflect.StructTag(tag).Get(enc) != "" {
pass.Reportf(field.Pos(), "struct field %s has %s tag but is not exported", field.Name(), enc)
return
}
}
}
// checkTagDuplicates checks a single struct field tag to see if any tags are
// duplicated. nearest is the field that's closest to the field being checked,
// while still being part of the top-level struct type.
func checkTagDuplicates(pass *analysis.Pass, tag, key string, nearest, field *types.Var, seen *map[[2]string]token.Pos) {
val := reflect.StructTag(tag).Get(key)
if val == "-" {
// Ignored, even if the field is anonymous.
return
}
if val == "" || val[0] == ',' {
if field.Anonymous() {
typ, ok := field.Type().Underlying().(*types.Struct)
if !ok {
return
}
for i := 0; i < typ.NumFields(); i++ {
field := typ.Field(i)
if !field.Exported() {
continue
}
tag := typ.Tag(i)
checkTagDuplicates(pass, tag, key, nearest, field, seen)
}
}
// Ignored if the field isn't anonymous.
return
}
if key == "xml" && field.Name() == "XMLName" {
// XMLName defines the XML element name of the struct being
// checked. That name cannot collide with element or attribute
// names defined on other fields of the struct. Vet does not have a
// check for untagged fields of type struct defining their own name
// by containing a field named XMLName; see issue 18256.
return
}
if i := strings.Index(val, ","); i >= 0 {
if key == "xml" {
// Use a separate namespace for XML attributes.
for _, opt := range strings.Split(val[i:], ",") {
if opt == "attr" {
key += " attribute" // Key is part of the error message.
break
}
}
}
val = val[:i]
}
if *seen == nil {
*seen = map[[2]string]token.Pos{}
}
if pos, ok := (*seen)[[2]string{key, val}]; ok {
posn := pass.Fset.Position(pos)
posn.Filename = filepath.Base(posn.Filename)
posn.Column = 0
pass.Reportf(nearest.Pos(), "struct field %s repeats %s tag %q also at %s", field.Name(), key, val, posn)
} else {
(*seen)[[2]string{key, val}] = field.Pos()
}
}
var (
errTagSyntax = errors.New("bad syntax for struct tag pair")
errTagKeySyntax = errors.New("bad syntax for struct tag key")
errTagValueSyntax = errors.New("bad syntax for struct tag value")
errTagValueSpace = errors.New("suspicious space in struct tag value")
errTagSpace = errors.New("key:\"value\" pairs not separated by spaces")
)
// validateStructTag parses the struct tag and returns an error if it is not
// in the canonical format, which is a space-separated list of key:"value"
// settings. The value may contain spaces.
func validateStructTag(tag string) error {
// This code is based on the StructTag.Get code in package reflect.
n := 0
for ; tag != ""; n++ {
if n > 0 && tag != "" && tag[0] != ' ' {
// More restrictive than reflect, but catches likely mistakes
// like `x:"foo",y:"bar"`, which parses as `x:"foo" ,y:"bar"` with second key ",y".
return errTagSpace
}
// Skip leading space.
i := 0
for i < len(tag) && tag[i] == ' ' {
i++
}
tag = tag[i:]
if tag == "" {
break
}
// Scan to colon. A space, a quote or a control character is a syntax error.
// Strictly speaking, control chars include the range [0x7f, 0x9f], not just
// [0x00, 0x1f], but in practice, we ignore the multi-byte control characters
// as it is simpler to inspect the tag's bytes than the tag's runes.
i = 0
for i < len(tag) && tag[i] > ' ' && tag[i] != ':' && tag[i] != '"' && tag[i] != 0x7f {
i++
}
if i == 0 {
return errTagKeySyntax
}
if i+1 >= len(tag) || tag[i] != ':' {
return errTagSyntax
}
if tag[i+1] != '"' {
return errTagValueSyntax
}
key := tag[:i]
tag = tag[i+1:]
// Scan quoted string to find value.
i = 1
for i < len(tag) && tag[i] != '"' {
if tag[i] == '\\' {
i++
}
i++
}
if i >= len(tag) {
return errTagValueSyntax
}
qvalue := tag[:i+1]
tag = tag[i+1:]
value, err := strconv.Unquote(qvalue)
if err != nil {
return errTagValueSyntax
}
if !checkTagSpaces[key] {
continue
}
switch key {
case "xml":
// If the first or last character in the XML tag is a space, it is
// suspicious.
if strings.Trim(value, " ") != value {
return errTagValueSpace
}
// If there are multiple spaces, they are suspicious.
if strings.Count(value, " ") > 1 {
return errTagValueSpace
}
// If there is no comma, skip the rest of the checks.
comma := strings.IndexRune(value, ',')
if comma < 0 {
continue
}
// If the character before a comma is a space, this is suspicious.
if comma > 0 && value[comma-1] == ' ' {
return errTagValueSpace
}
value = value[comma+1:]
case "json":
// JSON allows using spaces in the name, so skip it.
comma := strings.IndexRune(value, ',')
if comma < 0 {
continue
}
value = value[comma+1:]
}
if strings.IndexByte(value, ' ') >= 0 {
return errTagValueSpace
}
}
return nil
}
src/cmd/vendor/golang.org/x/tools/go/analysis/passes/tests/tests.go 0 → 100644
View file @ 8b469209
// Copyright 2015 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
// Package tests defines an Analyzer that checks for common mistaken
// usages of tests and examples.
package tests
import (
"go/ast"
"go/types"
"strings"
"unicode"
"unicode/utf8"
"golang.org/x/tools/go/analysis"
)
const Doc = `check for common mistaken usages of tests and examples
The tests checker walks Test, Benchmark and Example functions checking
malformed names, wrong signatures and examples documenting non-existent
identifiers.`
var Analyzer = &analysis.Analyzer{
Name: "tests",
Doc: Doc,
Run: run,
}
func run(pass *analysis.Pass) (interface{}, error) {
for _, f := range pass.Files {
if !strings.HasSuffix(pass.Fset.File(f.Pos()).Name(), "_test.go") {
continue
}
for _, decl := range f.Decls {
fn, ok := decl.(*ast.FuncDecl)
if !ok || fn.Recv != nil {
// Ignore non-functions or functions with receivers.
continue
}
switch {
case strings.HasPrefix(fn.Name.Name, "Example"):
checkExample(pass, fn)
case strings.HasPrefix(fn.Name.Name, "Test"):
checkTest(pass, fn, "Test")
case strings.HasPrefix(fn.Name.Name, "Benchmark"):
checkTest(pass, fn, "Benchmark")
}
}
}
return nil, nil
}
func isExampleSuffix(s string) bool {
r, size := utf8.DecodeRuneInString(s)
return size > 0 && unicode.IsLower(r)
}
func isTestSuffix(name string) bool {
if len(name) == 0 {
// "Test" is ok.
return true
}
r, _ := utf8.DecodeRuneInString(name)
return !unicode.IsLower(r)
}
func isTestParam(typ ast.Expr, wantType string) bool {
ptr, ok := typ.(*ast.StarExpr)
if !ok {
// Not a pointer.
return false
}
// No easy way of making sure it's a *testing.T or *testing.B:
// ensure the name of the type matches.
if name, ok := ptr.X.(*ast.Ident); ok {
return name.Name == wantType
}
if sel, ok := ptr.X.(*ast.SelectorExpr); ok {
return sel.Sel.Name == wantType
}
return false
}
func lookup(pkg *types.Package, name string) types.Object {
if o := pkg.Scope().Lookup(name); o != nil {
return o
}
// If this package is ".../foo_test" and it imports a package
// ".../foo", try looking in the latter package.
// This heuristic should work even on build systems that do not
// record any special link between the packages.
if basePath := strings.TrimSuffix(pkg.Path(), "_test"); basePath != pkg.Path() {
for _, imp := range pkg.Imports() {
if imp.Path() == basePath {
return imp.Scope().Lookup(name)
}
}
}
return nil
}
func checkExample(pass *analysis.Pass, fn *ast.FuncDecl) {
fnName := fn.Name.Name
if params := fn.Type.Params; len(params.List) != 0 {
pass.Reportf(fn.Pos(), "%s should be niladic", fnName)
}
if results := fn.Type.Results; results != nil && len(results.List) != 0 {
pass.Reportf(fn.Pos(), "%s should return nothing", fnName)
}
if fnName == "Example" {
// Nothing more to do.
return
}
var (
exName = strings.TrimPrefix(fnName, "Example")
elems = strings.SplitN(exName, "_", 3)
ident = elems[0]
obj = lookup(pass.Pkg, ident)
)
if ident != "" && obj == nil {
// Check ExampleFoo and ExampleBadFoo.
pass.Reportf(fn.Pos(), "%s refers to unknown identifier: %s", fnName, ident)
// Abort since obj is absent and no subsequent checks can be performed.
return
}
if len(elems) < 2 {
// Nothing more to do.
return
}
if ident == "" {
// Check Example_suffix and Example_BadSuffix.
if residual := strings.TrimPrefix(exName, "_"); !isExampleSuffix(residual) {
pass.Reportf(fn.Pos(), "%s has malformed example suffix: %s", fnName, residual)
}
return
}
mmbr := elems[1]
if !isExampleSuffix(mmbr) {
// Check ExampleFoo_Method and ExampleFoo_BadMethod.
if obj, _, _ := types.LookupFieldOrMethod(obj.Type(), true, obj.Pkg(), mmbr); obj == nil {
pass.Reportf(fn.Pos(), "%s refers to unknown field or method: %s.%s", fnName, ident, mmbr)
}
}
if len(elems) == 3 && !isExampleSuffix(elems[2]) {
// Check ExampleFoo_Method_suffix and ExampleFoo_Method_Badsuffix.
pass.Reportf(fn.Pos(), "%s has malformed example suffix: %s", fnName, elems[2])
}
}
func checkTest(pass *analysis.Pass, fn *ast.FuncDecl, prefix string) {
// Want functions with 0 results and 1 parameter.
if fn.Type.Results != nil && len(fn.Type.Results.List) > 0 ||
fn.Type.Params == nil ||
len(fn.Type.Params.List) != 1 ||
len(fn.Type.Params.List[0].Names) > 1 {
return
}
// The param must look like a *testing.T or *testing.B.
if !isTestParam(fn.Type.Params.List[0].Type, prefix[:1]) {
return
}
if !isTestSuffix(fn.Name.Name[len(prefix):]) {
pass.Reportf(fn.Pos(), "%s has malformed name: first letter after '%s' must not be lowercase", fn.Name.Name, prefix)
}
}
src/cmd/vendor/golang.org/x/tools/go/analysis/passes/unreachable/unreachable.go 0 → 100644
View file @ 8b469209
// Copyright 2013 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
// Package unreachable defines an Analyzer that checks for unreachable code.
package unreachable
// TODO(adonovan): use the new cfg package, which is more precise.
import (
"go/ast"
"go/token"
"log"
"golang.org/x/tools/go/analysis"
"golang.org/x/tools/go/analysis/passes/inspect"
"golang.org/x/tools/go/ast/inspector"
)
const Doc = `check for unreachable code
The unreachable analyzer finds statements that execution can never reach
because they are preceded by an return statement, a call to panic, an
infinite loop, or similar constructs.`
var Analyzer = &analysis.Analyzer{
Name: "unreachable",
Doc: Doc,
Requires: []*analysis.Analyzer{inspect.Analyzer},
RunDespiteErrors: true,
Run: run,
}
func run(pass *analysis.Pass) (interface{}, error) {
inspect := pass.ResultOf[inspect.Analyzer].(*inspector.Inspector)
nodeFilter := []ast.Node{
(*ast.FuncDecl)(nil),
(*ast.FuncLit)(nil),
}
inspect.Preorder(nodeFilter, func(n ast.Node) {
var body *ast.BlockStmt
switch n := n.(type) {
case *ast.FuncDecl:
body = n.Body
case *ast.FuncLit:
body = n.Body
}
if body == nil {
return
}
d := &deadState{
pass: pass,
hasBreak: make(map[ast.Stmt]bool),
hasGoto: make(map[string]bool),
labels: make(map[string]ast.Stmt),
}
d.findLabels(body)
d.reachable = true
d.findDead(body)
})
return nil, nil
}
type deadState struct {
pass *analysis.Pass
hasBreak map[ast.Stmt]bool
hasGoto map[string]bool
labels map[string]ast.Stmt
breakTarget ast.Stmt
reachable bool
}
// findLabels gathers information about the labels defined and used by stmt
// and about which statements break, whether a label is involved or not.
func (d *deadState) findLabels(stmt ast.Stmt) {
switch x := stmt.(type) {
default:
log.Fatalf("%s: internal error in findLabels: unexpected statement %T", d.pass.Fset.Position(x.Pos()), x)
case *ast.AssignStmt,
*ast.BadStmt,
*ast.DeclStmt,
*ast.DeferStmt,
*ast.EmptyStmt,
*ast.ExprStmt,
*ast.GoStmt,
*ast.IncDecStmt,
*ast.ReturnStmt,
*ast.SendStmt:
// no statements inside
case *ast.BlockStmt:
for _, stmt := range x.List {
d.findLabels(stmt)
}
case *ast.BranchStmt:
switch x.Tok {
case token.GOTO:
if x.Label != nil {
d.hasGoto[x.Label.Name] = true
}
case token.BREAK:
stmt := d.breakTarget
if x.Label != nil {
stmt = d.labels[x.Label.Name]
}
if stmt != nil {
d.hasBreak[stmt] = true
}
}
case *ast.IfStmt:
d.findLabels(x.Body)
if x.Else != nil {
d.findLabels(x.Else)
}
case *ast.LabeledStmt:
d.labels[x.Label.Name] = x.Stmt
d.findLabels(x.Stmt)
// These cases are all the same, but the x.Body only works
// when the specific type of x is known, so the cases cannot
// be merged.
case *ast.ForStmt:
outer := d.breakTarget
d.breakTarget = x
d.findLabels(x.Body)
d.breakTarget = outer
case *ast.RangeStmt:
outer := d.breakTarget
d.breakTarget = x
d.findLabels(x.Body)
d.breakTarget = outer
case *ast.SelectStmt:
outer := d.breakTarget
d.breakTarget = x
d.findLabels(x.Body)
d.breakTarget = outer
case *ast.SwitchStmt:
outer := d.breakTarget
d.breakTarget = x
d.findLabels(x.Body)
d.breakTarget = outer
case *ast.TypeSwitchStmt:
outer := d.breakTarget
d.breakTarget = x
d.findLabels(x.Body)
d.breakTarget = outer
case *ast.CommClause:
for _, stmt := range x.Body {
d.findLabels(stmt)
}
case *ast.CaseClause:
for _, stmt := range x.Body {
d.findLabels(stmt)
}
}
}
// findDead walks the statement looking for dead code.
// If d.reachable is false on entry, stmt itself is dead.
// When findDead returns, d.reachable tells whether the
// statement following stmt is reachable.
func (d *deadState) findDead(stmt ast.Stmt) {
// Is this a labeled goto target?
// If so, assume it is reachable due to the goto.
// This is slightly conservative, in that we don't
// check that the goto is reachable, so
// L: goto L
// will not provoke a warning.
// But it's good enough.
if x, isLabel := stmt.(*ast.LabeledStmt); isLabel && d.hasGoto[x.Label.Name] {
d.reachable = true
}
if !d.reachable {
switch stmt.(type) {
case *ast.EmptyStmt:
// do not warn about unreachable empty statements
default:
d.pass.Reportf(stmt.Pos(), "unreachable code")
d.reachable = true // silence error about next statement
}
}
switch x := stmt.(type) {
default:
log.Fatalf("%s: internal error in findDead: unexpected statement %T", d.pass.Fset.Position(x.Pos()), x)
case *ast.AssignStmt,
*ast.BadStmt,
*ast.DeclStmt,
*ast.DeferStmt,
*ast.EmptyStmt,
*ast.GoStmt,
*ast.IncDecStmt,
*ast.SendStmt:
// no control flow
case *ast.BlockStmt:
for _, stmt := range x.List {
d.findDead(stmt)
}
case *ast.BranchStmt:
switch x.Tok {
case token.BREAK, token.GOTO, token.FALLTHROUGH:
d.reachable = false
case token.CONTINUE:
// NOTE: We accept "continue" statements as terminating.
// They are not necessary in the spec definition of terminating,
// because a continue statement cannot be the final statement
// before a return. But for the more general problem of syntactically
// identifying dead code, continue redirects control flow just
// like the other terminating statements.
d.reachable = false
}
case *ast.ExprStmt:
// Call to panic?
call, ok := x.X.(*ast.CallExpr)
if ok {
name, ok := call.Fun.(*ast.Ident)
if ok && name.Name == "panic" && name.Obj == nil {
d.reachable = false
}
}
case *ast.ForStmt:
d.findDead(x.Body)
d.reachable = x.Cond != nil || d.hasBreak[x]
case *ast.IfStmt:
d.findDead(x.Body)
if x.Else != nil {
r := d.reachable
d.reachable = true
d.findDead(x.Else)
d.reachable = d.reachable || r
} else {
// might not have executed if statement
d.reachable = true
}
case *ast.LabeledStmt:
d.findDead(x.Stmt)
case *ast.RangeStmt:
d.findDead(x.Body)
d.reachable = true
case *ast.ReturnStmt:
d.reachable = false
case *ast.SelectStmt:
// NOTE: Unlike switch and type switch below, we don't care
// whether a select has a default, because a select without a
// default blocks until one of the cases can run. That's different
// from a switch without a default, which behaves like it has
// a default with an empty body.
anyReachable := false
for _, comm := range x.Body.List {
d.reachable = true
for _, stmt := range comm.(*ast.CommClause).Body {
d.findDead(stmt)
}
anyReachable = anyReachable || d.reachable
}
d.reachable = anyReachable || d.hasBreak[x]
case *ast.SwitchStmt:
anyReachable := false
hasDefault := false
for _, cas := range x.Body.List {
cc := cas.(*ast.CaseClause)
if cc.List == nil {
hasDefault = true
}
d.reachable = true
for _, stmt := range cc.Body {
d.findDead(stmt)
}
anyReachable = anyReachable || d.reachable
}
d.reachable = anyReachable || d.hasBreak[x] || !hasDefault
case *ast.TypeSwitchStmt:
anyReachable := false
hasDefault := false
for _, cas := range x.Body.List {
cc := cas.(*ast.CaseClause)
if cc.List == nil {
hasDefault = true
}
d.reachable = true
for _, stmt := range cc.Body {
d.findDead(stmt)
}
anyReachable = anyReachable || d.reachable
}
d.reachable = anyReachable || d.hasBreak[x] || !hasDefault
}
}
src/cmd/vendor/golang.org/x/tools/go/analysis/passes/unsafeptr/unsafeptr.go 0 → 100644
View file @ 8b469209
// Copyright 2014 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
// Package unsafeptr defines an Analyzer that checks for invalid
// conversions of uintptr to unsafe.Pointer.
package unsafeptr
import (
"go/ast"
"go/token"
"go/types"
"golang.org/x/tools/go/analysis"
"golang.org/x/tools/go/analysis/passes/inspect"
"golang.org/x/tools/go/ast/inspector"
)
const Doc = `check for invalid conversions of uintptr to unsafe.Pointer
The unsafeptr analyzer reports likely incorrect uses of unsafe.Pointer
to convert integers to pointers. A conversion from uintptr to
unsafe.Pointer is invalid if it implies that there is a uintptr-typed
word in memory that holds a pointer value, because that word will be
invisible to stack copying and to the garbage collector.`
var Analyzer = &analysis.Analyzer{
Name: "unsafeptr",
Doc: Doc,
Requires: []*analysis.Analyzer{inspect.Analyzer},
Run: run,
}
func run(pass *analysis.Pass) (interface{}, error) {
inspect := pass.ResultOf[inspect.Analyzer].(*inspector.Inspector)
nodeFilter := []ast.Node{
(*ast.CallExpr)(nil),
}
inspect.Preorder(nodeFilter, func(n ast.Node) {
x := n.(*ast.CallExpr)
if len(x.Args) != 1 {
return
}
if hasBasicType(pass.TypesInfo, x.Fun, types.UnsafePointer) &&
hasBasicType(pass.TypesInfo, x.Args[0], types.Uintptr) &&
!isSafeUintptr(pass.TypesInfo, x.Args[0]) {
pass.Reportf(x.Pos(), "possible misuse of unsafe.Pointer")
}
})
return nil, nil
}
// isSafeUintptr reports whether x - already known to be a uintptr -
// is safe to convert to unsafe.Pointer. It is safe if x is itself derived
// directly from an unsafe.Pointer via conversion and pointer arithmetic
// or if x is the result of reflect.Value.Pointer or reflect.Value.UnsafeAddr
// or obtained from the Data field of a *reflect.SliceHeader or *reflect.StringHeader.
func isSafeUintptr(info *types.Info, x ast.Expr) bool {
switch x := x.(type) {
case *ast.ParenExpr:
return isSafeUintptr(info, x.X)
case *ast.SelectorExpr:
switch x.Sel.Name {
case "Data":
// reflect.SliceHeader and reflect.StringHeader are okay,
// but only if they are pointing at a real slice or string.
// It's not okay to do:
// var x SliceHeader
// x.Data = uintptr(unsafe.Pointer(...))
// ... use x ...
// p := unsafe.Pointer(x.Data)
// because in the middle the garbage collector doesn't
// see x.Data as a pointer and so x.Data may be dangling
// by the time we get to the conversion at the end.
// For now approximate by saying that *Header is okay
// but Header is not.
pt, ok := info.Types[x.X].Type.(*types.Pointer)
if ok {
t, ok := pt.Elem().(*types.Named)
if ok && t.Obj().Pkg().Path() == "reflect" {
switch t.Obj().Name() {
case "StringHeader", "SliceHeader":
return true
}
}
}
}
case *ast.CallExpr:
switch len(x.Args) {
case 0:
// maybe call to reflect.Value.Pointer or reflect.Value.UnsafeAddr.
sel, ok := x.Fun.(*ast.SelectorExpr)
if !ok {
break
}
switch sel.Sel.Name {
case "Pointer", "UnsafeAddr":
t, ok := info.Types[sel.X].Type.(*types.Named)
if ok && t.Obj().Pkg().Path() == "reflect" && t.Obj().Name() == "Value" {
return true
}
}
case 1:
// maybe conversion of uintptr to unsafe.Pointer
return hasBasicType(info, x.Fun, types.Uintptr) &&
hasBasicType(info, x.Args[0], types.UnsafePointer)
}
case *ast.BinaryExpr:
switch x.Op {
case token.ADD, token.SUB, token.AND_NOT:
return isSafeUintptr(info, x.X) && !isSafeUintptr(info, x.Y)
}
}
return false
}
// hasBasicType reports whether x's type is a types.Basic with the given kind.
func hasBasicType(info *types.Info, x ast.Expr, kind types.BasicKind) bool {
t := info.Types[x].Type
if t != nil {
t = t.Underlying()
}
b, ok := t.(*types.Basic)
return ok && b.Kind() == kind
}
src/cmd/vendor/golang.org/x/tools/go/analysis/passes/unusedresult/unusedresult.go 0 → 100644
View file @ 8b469209
// Copyright 2015 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
// Package unusedresult defines an analyzer that checks for unused
// results of calls to certain pure functions.
package unusedresult
import (
"go/ast"
"go/token"
"go/types"
"sort"
"strings"
"golang.org/x/tools/go/analysis"
"golang.org/x/tools/go/analysis/passes/inspect"
"golang.org/x/tools/go/analysis/passes/internal/analysisutil"
"golang.org/x/tools/go/ast/inspector"
)
// TODO(adonovan): make this analysis modular: export a mustUseResult
// fact for each function that tail-calls one of the functions that we
// check, and check those functions too.
const Doc = `check for unused results of calls to some functions
Some functions like fmt.Errorf return a result and have no side effects,
so it is always a mistake to discard the result. This analyzer reports
calls to certain functions in which the result of the call is ignored.
The set of functions may be controlled using flags.`
var Analyzer = &analysis.Analyzer{
Name: "unusedresult",
Doc: Doc,
Requires: []*analysis.Analyzer{inspect.Analyzer},
Run: run,
}
// flags
var funcs, stringMethods stringSetFlag
func init() {
// TODO(adonovan): provide a comment syntax to allow users to
// add their functions to this set using facts.
funcs.Set("errors.New,fmt.Errorf,fmt.Sprintf,fmt.Sprint,sort.Reverse")
Analyzer.Flags.Var(&funcs, "funcs",
"comma-separated list of functions whose results must be used")
stringMethods.Set("Error,String")
Analyzer.Flags.Var(&stringMethods, "stringmethods",
"comma-separated list of names of methods of type func() string whose results must be used")
}
func run(pass *analysis.Pass) (interface{}, error) {
inspect := pass.ResultOf[inspect.Analyzer].(*inspector.Inspector)
nodeFilter := []ast.Node{
(*ast.ExprStmt)(nil),
}
inspect.Preorder(nodeFilter, func(n ast.Node) {
call, ok := analysisutil.Unparen(n.(*ast.ExprStmt).X).(*ast.CallExpr)
if !ok {
return // not a call statement
}
fun := analysisutil.Unparen(call.Fun)
if pass.TypesInfo.Types[fun].IsType() {
return // a conversion, not a call
}
selector, ok := fun.(*ast.SelectorExpr)
if !ok {
return // neither a method call nor a qualified ident
}
sel, ok := pass.TypesInfo.Selections[selector]
if ok && sel.Kind() == types.MethodVal {
// method (e.g. foo.String())
obj := sel.Obj().(*types.Func)
sig := sel.Type().(*types.Signature)
if types.Identical(sig, sigNoArgsStringResult) {
if stringMethods[obj.Name()] {
pass.Reportf(call.Lparen, "result of (%s).%s call not used",
sig.Recv().Type(), obj.Name())
}
}
} else if !ok {
// package-qualified function (e.g. fmt.Errorf)
obj := pass.TypesInfo.Uses[selector.Sel]
if obj, ok := obj.(*types.Func); ok {
qname := obj.Pkg().Path() + "." + obj.Name()
if funcs[qname] {
pass.Reportf(call.Lparen, "result of %v call not used", qname)
}
}
}
})
return nil, nil
}
// func() string
var sigNoArgsStringResult = types.NewSignature(nil, nil,
types.NewTuple(types.NewVar(token.NoPos, nil, "", types.Typ[types.String])),
false)
type stringSetFlag map[string]bool
func (ss *stringSetFlag) String() string {
var items []string
for item := range *ss {
items = append(items, item)
}
sort.Strings(items)
return strings.Join(items, ",")
}
func (ss *stringSetFlag) Set(s string) error {
m := make(map[string]bool) // clobber previous value
if s != "" {
for _, name := range strings.Split(s, ",") {
if name == "" {
continue // TODO: report error? proceed?
}
m[name] = true
}
}
*ss = m
return nil
}
src/cmd/vendor/golang.org/x/tools/go/analysis/validate.go 0 → 100644
View file @ 8b469209
package analysis
import (
"fmt"
"reflect"
"unicode"
)
// Validate reports an error if any of the analyzers are misconfigured.
// Checks include:
// that the name is a valid identifier;
// that analyzer names are unique;
// that the Requires graph is acylic;
// that analyzer fact types are unique;
// that each fact type is a pointer.
func Validate(analyzers []*Analyzer) error {
names := make(map[string]bool)
// Map each fact type to its sole generating analyzer.
factTypes := make(map[reflect.Type]*Analyzer)
// Traverse the Requires graph, depth first.
const (
white = iota
grey
black
finished
)
color := make(map[*Analyzer]uint8)
var visit func(a *Analyzer) error
visit = func(a *Analyzer) error {
if a == nil {
return fmt.Errorf("nil *Analyzer")
}
if color[a] == white {
color[a] = grey
// names
if !validIdent(a.Name) {
return fmt.Errorf("invalid analyzer name %q", a)
}
if names[a.Name] {
return fmt.Errorf("duplicate analyzer name %q", a)
}
names[a.Name] = true
if a.Doc == "" {
return fmt.Errorf("analyzer %q is undocumented", a)
}
// fact types
for _, f := range a.FactTypes {
if f == nil {
return fmt.Errorf("analyzer %s has nil FactType", a)
}
t := reflect.TypeOf(f)
if prev := factTypes[t]; prev != nil {
return fmt.Errorf("fact type %s registered by two analyzers: %v, %v",
t, a, prev)
}
if t.Kind() != reflect.Ptr {
return fmt.Errorf("%s: fact type %s is not a pointer", a, t)
}
factTypes[t] = a
}
// recursion
for i, req := range a.Requires {
if err := visit(req); err != nil {
return fmt.Errorf("%s.Requires[%d]: %v", a.Name, i, err)
}
}
color[a] = black
}
return nil
}
for _, a := range analyzers {
if err := visit(a); err != nil {
return err
}
}
// Reject duplicates among analyzers.
// Precondition: color[a] == black.
// Postcondition: color[a] == finished.
for _, a := range analyzers {
if color[a] == finished {
return fmt.Errorf("duplicate analyzer: %s", a.Name)
}
color[a] = finished
}
return nil
}
func validIdent(name string) bool {
for i, r := range name {
if !(r == '_' || unicode.IsLetter(r) || i > 0 && unicode.IsDigit(r)) {
return false
}
}
return name != ""
}
src/cmd/vendor/golang.org/x/tools/go/ast/astutil/enclosing.go 0 → 100644
View file @ 8b469209
// Copyright 2013 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
package astutil
// This file defines utilities for working with source positions.
import (
"fmt"
"go/ast"
"go/token"
"sort"
)
// PathEnclosingInterval returns the node that encloses the source
// interval [start, end), and all its ancestors up to the AST root.
//
// The definition of "enclosing" used by this function considers
// additional whitespace abutting a node to be enclosed by it.
// In this example:
//
// z := x + y // add them
// <-A->
// <----B----->
//
// the ast.BinaryExpr(+) node is considered to enclose interval B
// even though its [Pos()..End()) is actually only interval A.
// This behaviour makes user interfaces more tolerant of imperfect
// input.
//
// This function treats tokens as nodes, though they are not included
// in the result. e.g. PathEnclosingInterval("+") returns the
// enclosing ast.BinaryExpr("x + y").
//
// If start==end, the 1-char interval following start is used instead.
//
// The 'exact' result is true if the interval contains only path[0]
// and perhaps some adjacent whitespace. It is false if the interval
// overlaps multiple children of path[0], or if it contains only
// interior whitespace of path[0].
// In this example:
//
// z := x + y // add them
// <--C--> <---E-->
// ^
// D
//
// intervals C, D and E are inexact. C is contained by the
// z-assignment statement, because it spans three of its children (:=,
// x, +). So too is the 1-char interval D, because it contains only
// interior whitespace of the assignment. E is considered interior
// whitespace of the BlockStmt containing the assignment.
//
// Precondition: [start, end) both lie within the same file as root.
// TODO(adonovan): return (nil, false) in this case and remove precond.
// Requires FileSet; see loader.tokenFileContainsPos.
//
// Postcondition: path is never nil; it always contains at least 'root'.
//
func PathEnclosingInterval(root *ast.File, start, end token.Pos) (path []ast.Node, exact bool) {
// fmt.Printf("EnclosingInterval %d %d\n", start, end) // debugging
// Precondition: node.[Pos..End) and adjoining whitespace contain [start, end).
var visit func(node ast.Node) bool
visit = func(node ast.Node) bool {
path = append(path, node)
nodePos := node.Pos()
nodeEnd := node.End()
// fmt.Printf("visit(%T, %d, %d)\n", node, nodePos, nodeEnd) // debugging
// Intersect [start, end) with interval of node.
if start < nodePos {
start = nodePos
}
if end > nodeEnd {
end = nodeEnd
}
// Find sole child that contains [start, end).
children := childrenOf(node)
l := len(children)
for i, child := range children {
// [childPos, childEnd) is unaugmented interval of child.
childPos := child.Pos()
childEnd := child.End()
// [augPos, augEnd) is whitespace-augmented interval of child.
augPos := childPos
augEnd := childEnd
if i > 0 {
augPos = children[i-1].End() // start of preceding whitespace
}
if i < l-1 {
nextChildPos := children[i+1].Pos()
// Does [start, end) lie between child and next child?
if start >= augEnd && end <= nextChildPos {
return false // inexact match
}
augEnd = nextChildPos // end of following whitespace
}
// fmt.Printf("\tchild %d: [%d..%d)\tcontains interval [%d..%d)?\n",
// i, augPos, augEnd, start, end) // debugging
// Does augmented child strictly contain [start, end)?
if augPos <= start && end <= augEnd {
_, isToken := child.(tokenNode)
return isToken || visit(child)
}
// Does [start, end) overlap multiple children?
// i.e. left-augmented child contains start
// but LR-augmented child does not contain end.
if start < childEnd && end > augEnd {
break
}
}
// No single child contained [start, end),
// so node is the result. Is it exact?
// (It's tempting to put this condition before the
// child loop, but it gives the wrong result in the
// case where a node (e.g. ExprStmt) and its sole
// child have equal intervals.)
if start == nodePos && end == nodeEnd {
return true // exact match
}
return false // inexact: overlaps multiple children
}
if start > end {
start, end = end, start
}
if start < root.End() && end > root.Pos() {
if start == end {
end = start + 1 // empty interval => interval of size 1
}
exact = visit(root)
// Reverse the path:
for i, l := 0, len(path); i < l/2; i++ {
path[i], path[l-1-i] = path[l-1-i], path[i]
}
} else {
// Selection lies within whitespace preceding the
// first (or following the last) declaration in the file.
// The result nonetheless always includes the ast.File.
path = append(path, root)
}
return
}
// tokenNode is a dummy implementation of ast.Node for a single token.
// They are used transiently by PathEnclosingInterval but never escape
// this package.
//
type tokenNode struct {
pos token.Pos
end token.Pos
}
func (n tokenNode) Pos() token.Pos {
return n.pos
}
func (n tokenNode) End() token.Pos {
return n.end
}
func tok(pos token.Pos, len int) ast.Node {
return tokenNode{pos, pos + token.Pos(len)}
}
// childrenOf returns the direct non-nil children of ast.Node n.
// It may include fake ast.Node implementations for bare tokens.
// it is not safe to call (e.g.) ast.Walk on such nodes.
//
func childrenOf(n ast.Node) []ast.Node {
var children []ast.Node
// First add nodes for all true subtrees.
ast.Inspect(n, func(node ast.Node) bool {
if node == n { // push n
return true // recur
}
if node != nil { // push child
children = append(children, node)
}
return false // no recursion
})
// Then add fake Nodes for bare tokens.
switch n := n.(type) {
case *ast.ArrayType:
children = append(children,
tok(n.Lbrack, len("[")),
tok(n.Elt.End(), len("]")))
case *ast.AssignStmt:
children = append(children,
tok(n.TokPos, len(n.Tok.String())))
case *ast.BasicLit:
children = append(children,
tok(n.ValuePos, len(n.Value)))
case *ast.BinaryExpr:
children = append(children, tok(n.OpPos, len(n.Op.String())))
case *ast.BlockStmt:
children = append(children,
tok(n.Lbrace, len("{")),
tok(n.Rbrace, len("}")))
case *ast.BranchStmt:
children = append(children,
tok(n.TokPos, len(n.Tok.String())))
case *ast.CallExpr:
children = append(children,
tok(n.Lparen, len("(")),
tok(n.Rparen, len(")")))
if n.Ellipsis != 0 {
children = append(children, tok(n.Ellipsis, len("...")))
}
case *ast.CaseClause:
if n.List == nil {
children = append(children,
tok(n.Case, len("default")))
} else {
children = append(children,
tok(n.Case, len("case")))
}
children = append(children, tok(n.Colon, len(":")))
case *ast.ChanType:
switch n.Dir {
case ast.RECV:
children = append(children, tok(n.Begin, len("<-chan")))
case ast.SEND:
children = append(children, tok(n.Begin, len("chan<-")))
case ast.RECV | ast.SEND:
children = append(children, tok(n.Begin, len("chan")))
}
case *ast.CommClause:
if n.Comm == nil {
children = append(children,
tok(n.Case, len("default")))
} else {
children = append(children,
tok(n.Case, len("case")))
}
children = append(children, tok(n.Colon, len(":")))
case *ast.Comment:
// nop
case *ast.CommentGroup:
// nop
case *ast.CompositeLit:
children = append(children,
tok(n.Lbrace, len("{")),
tok(n.Rbrace, len("{")))
case *ast.DeclStmt:
// nop
case *ast.DeferStmt:
children = append(children,
tok(n.Defer, len("defer")))
case *ast.Ellipsis:
children = append(children,
tok(n.Ellipsis, len("...")))
case *ast.EmptyStmt:
// nop
case *ast.ExprStmt:
// nop
case *ast.Field:
// TODO(adonovan): Field.{Doc,Comment,Tag}?
case *ast.FieldList:
children = append(children,
tok(n.Opening, len("(")),
tok(n.Closing, len(")")))
case *ast.File:
// TODO test: Doc
children = append(children,
tok(n.Package, len("package")))
case *ast.ForStmt:
children = append(children,
tok(n.For, len("for")))
case *ast.FuncDecl:
// TODO(adonovan): FuncDecl.Comment?
// Uniquely, FuncDecl breaks the invariant that
// preorder traversal yields tokens in lexical order:
// in fact, FuncDecl.Recv precedes FuncDecl.Type.Func.
//
// As a workaround, we inline the case for FuncType
// here and order things correctly.
//
children = nil // discard ast.Walk(FuncDecl) info subtrees
children = append(children, tok(n.Type.Func, len("func")))
if n.Recv != nil {
children = append(children, n.Recv)
}
children = append(children, n.Name)
if n.Type.Params != nil {
children = append(children, n.Type.Params)
}
if n.Type.Results != nil {
children = append(children, n.Type.Results)
}
if n.Body != nil {
children = append(children, n.Body)
}
case *ast.FuncLit:
// nop
case *ast.FuncType:
if n.Func != 0 {
children = append(children,
tok(n.Func, len("func")))
}
case *ast.GenDecl:
children = append(children,
tok(n.TokPos, len(n.Tok.String())))
if n.Lparen != 0 {
children = append(children,
tok(n.Lparen, len("(")),
tok(n.Rparen, len(")")))
}
case *ast.GoStmt:
children = append(children,
tok(n.Go, len("go")))
case *ast.Ident:
children = append(children,
tok(n.NamePos, len(n.Name)))
case *ast.IfStmt:
children = append(children,
tok(n.If, len("if")))
case *ast.ImportSpec:
// TODO(adonovan): ImportSpec.{Doc,EndPos}?
case *ast.IncDecStmt:
children = append(children,
tok(n.TokPos, len(n.Tok.String())))
case *ast.IndexExpr:
children = append(children,
tok(n.Lbrack, len("{")),
tok(n.Rbrack, len("}")))
case *ast.InterfaceType:
children = append(children,
tok(n.Interface, len("interface")))
case *ast.KeyValueExpr:
children = append(children,
tok(n.Colon, len(":")))
case *ast.LabeledStmt:
children = append(children,
tok(n.Colon, len(":")))
case *ast.MapType:
children = append(children,
tok(n.Map, len("map")))
case *ast.ParenExpr:
children = append(children,
tok(n.Lparen, len("(")),
tok(n.Rparen, len(")")))
case *ast.RangeStmt:
children = append(children,
tok(n.For, len("for")),
tok(n.TokPos, len(n.Tok.String())))
case *ast.ReturnStmt:
children = append(children,
tok(n.Return, len("return")))
case *ast.SelectStmt:
children = append(children,
tok(n.Select, len("select")))
case *ast.SelectorExpr:
// nop
case *ast.SendStmt:
children = append(children,
tok(n.Arrow, len("<-")))
case *ast.SliceExpr:
children = append(children,
tok(n.Lbrack, len("[")),
tok(n.Rbrack, len("]")))
case *ast.StarExpr:
children = append(children, tok(n.Star, len("*")))
case *ast.StructType:
children = append(children, tok(n.Struct, len("struct")))
case *ast.SwitchStmt:
children = append(children, tok(n.Switch, len("switch")))
case *ast.TypeAssertExpr:
children = append(children,
tok(n.Lparen-1, len(".")),
tok(n.Lparen, len("(")),
tok(n.Rparen, len(")")))
case *ast.TypeSpec:
// TODO(adonovan): TypeSpec.{Doc,Comment}?
case *ast.TypeSwitchStmt:
children = append(children, tok(n.Switch, len("switch")))
case *ast.UnaryExpr:
children = append(children, tok(n.OpPos, len(n.Op.String())))
case *ast.ValueSpec:
// TODO(adonovan): ValueSpec.{Doc,Comment}?
case *ast.BadDecl, *ast.BadExpr, *ast.BadStmt:
// nop
}
// TODO(adonovan): opt: merge the logic of ast.Inspect() into
// the switch above so we can make interleaved callbacks for
// both Nodes and Tokens in the right order and avoid the need
// to sort.
sort.Sort(byPos(children))
return children
}
type byPos []ast.Node
func (sl byPos) Len() int {
return len(sl)
}
func (sl byPos) Less(i, j int) bool {
return sl[i].Pos() < sl[j].Pos()
}
func (sl byPos) Swap(i, j int) {
sl[i], sl[j] = sl[j], sl[i]
}
// NodeDescription returns a description of the concrete type of n suitable
// for a user interface.
//
// TODO(adonovan): in some cases (e.g. Field, FieldList, Ident,
// StarExpr) we could be much more specific given the path to the AST
// root. Perhaps we should do that.
//
func NodeDescription(n ast.Node) string {
switch n := n.(type) {
case *ast.ArrayType:
return "array type"
case *ast.AssignStmt:
return "assignment"
case *ast.BadDecl:
return "bad declaration"
case *ast.BadExpr:
return "bad expression"
case *ast.BadStmt:
return "bad statement"
case *ast.BasicLit:
return "basic literal"
case *ast.BinaryExpr:
return fmt.Sprintf("binary %s operation", n.Op)
case *ast.BlockStmt:
return "block"
case *ast.BranchStmt:
switch n.Tok {
case token.BREAK:
return "break statement"
case token.CONTINUE:
return "continue statement"
case token.GOTO:
return "goto statement"
case token.FALLTHROUGH:
return "fall-through statement"
}
case *ast.CallExpr:
if len(n.Args) == 1 && !n.Ellipsis.IsValid() {
return "function call (or conversion)"
}
return "function call"
case *ast.CaseClause:
return "case clause"
case *ast.ChanType:
return "channel type"
case *ast.CommClause:
return "communication clause"
case *ast.Comment:
return "comment"
case *ast.CommentGroup:
return "comment group"
case *ast.CompositeLit:
return "composite literal"
case *ast.DeclStmt:
return NodeDescription(n.Decl) + " statement"
case *ast.DeferStmt:
return "defer statement"
case *ast.Ellipsis:
return "ellipsis"
case *ast.EmptyStmt:
return "empty statement"
case *ast.ExprStmt:
return "expression statement"
case *ast.Field:
// Can be any of these:
// struct {x, y int} -- struct field(s)
// struct {T} -- anon struct field
// interface {I} -- interface embedding
// interface {f()} -- interface method
// func (A) func(B) C -- receiver, param(s), result(s)
return "field/method/parameter"
case *ast.FieldList:
return "field/method/parameter list"
case *ast.File:
return "source file"
case *ast.ForStmt:
return "for loop"
case *ast.FuncDecl:
return "function declaration"
case *ast.FuncLit:
return "function literal"
case *ast.FuncType:
return "function type"
case *ast.GenDecl:
switch n.Tok {
case token.IMPORT:
return "import declaration"
case token.CONST:
return "constant declaration"
case token.TYPE:
return "type declaration"
case token.VAR:
return "variable declaration"
}
case *ast.GoStmt:
return "go statement"
case *ast.Ident:
return "identifier"
case *ast.IfStmt:
return "if statement"
case *ast.ImportSpec:
return "import specification"
case *ast.IncDecStmt:
if n.Tok == token.INC {
return "increment statement"
}
return "decrement statement"
case *ast.IndexExpr:
return "index expression"
case *ast.InterfaceType:
return "interface type"
case *ast.KeyValueExpr:
return "key/value association"
case *ast.LabeledStmt:
return "statement label"
case *ast.MapType:
return "map type"
case *ast.Package:
return "package"
case *ast.ParenExpr:
return "parenthesized " + NodeDescription(n.X)
case *ast.RangeStmt:
return "range loop"
case *ast.ReturnStmt:
return "return statement"
case *ast.SelectStmt:
return "select statement"
case *ast.SelectorExpr:
return "selector"
case *ast.SendStmt:
return "channel send"
case *ast.SliceExpr:
return "slice expression"
case *ast.StarExpr:
return "*-operation" // load/store expr or pointer type
case *ast.StructType:
return "struct type"
case *ast.SwitchStmt:
return "switch statement"
case *ast.TypeAssertExpr:
return "type assertion"
case *ast.TypeSpec:
return "type specification"
case *ast.TypeSwitchStmt:
return "type switch"
case *ast.UnaryExpr:
return fmt.Sprintf("unary %s operation", n.Op)
case *ast.ValueSpec:
return "value specification"
}
panic(fmt.Sprintf("unexpected node type: %T", n))
}
src/cmd/vendor/golang.org/x/tools/go/ast/astutil/imports.go 0 → 100644
View file @ 8b469209
// Copyright 2013 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
// Package astutil contains common utilities for working with the Go AST.
package astutil // import "golang.org/x/tools/go/ast/astutil"
import (
"fmt"
"go/ast"
"go/token"
"strconv"
"strings"
)
// AddImport adds the import path to the file f, if absent.
func AddImport(fset *token.FileSet, f *ast.File, ipath string) (added bool) {
return AddNamedImport(fset, f, "", ipath)
}
// AddNamedImport adds the import path to the file f, if absent.
// If name is not empty, it is used to rename the import.
//
// For example, calling
// AddNamedImport(fset, f, "pathpkg", "path")
// adds
// import pathpkg "path"
func AddNamedImport(fset *token.FileSet, f *ast.File, name, ipath string) (added bool) {
if imports(f, ipath) {
return false
}
newImport := &ast.ImportSpec{
Path: &ast.BasicLit{
Kind: token.STRING,
Value: strconv.Quote(ipath),
},
}
if name != "" {
newImport.Name = &ast.Ident{Name: name}
}
// Find an import decl to add to.
// The goal is to find an existing import
// whose import path has the longest shared
// prefix with ipath.
var (
bestMatch = -1 // length of longest shared prefix
lastImport = -1 // index in f.Decls of the file's final import decl
impDecl *ast.GenDecl // import decl containing the best match
impIndex = -1 // spec index in impDecl containing the best match
isThirdPartyPath = isThirdParty(ipath)
)
for i, decl := range f.Decls {
gen, ok := decl.(*ast.GenDecl)
if ok && gen.Tok == token.IMPORT {
lastImport = i
// Do not add to import "C", to avoid disrupting the
// association with its doc comment, breaking cgo.
if declImports(gen, "C") {
continue
}
// Match an empty import decl if that's all that is available.
if len(gen.Specs) == 0 && bestMatch == -1 {
impDecl = gen
}
// Compute longest shared prefix with imports in this group and find best
// matched import spec.
// 1. Always prefer import spec with longest shared prefix.
// 2. While match length is 0,
// - for stdlib package: prefer first import spec.
// - for third party package: prefer first third party import spec.
// We cannot use last import spec as best match for third party package
// because grouped imports are usually placed last by goimports -local
// flag.
// See issue #19190.
seenAnyThirdParty := false
for j, spec := range gen.Specs {
impspec := spec.(*ast.ImportSpec)
p := importPath(impspec)
n := matchLen(p, ipath)
if n > bestMatch || (bestMatch == 0 && !seenAnyThirdParty && isThirdPartyPath) {
bestMatch = n
impDecl = gen
impIndex = j
}
seenAnyThirdParty = seenAnyThirdParty || isThirdParty(p)
}
}
}
// If no import decl found, add one after the last import.
if impDecl == nil {
impDecl = &ast.GenDecl{
Tok: token.IMPORT,
}
if lastImport >= 0 {
impDecl.TokPos = f.Decls[lastImport].End()
} else {
// There are no existing imports.
// Our new import, preceded by a blank line, goes after the package declaration
// and after the comment, if any, that starts on the same line as the
// package declaration.
impDecl.TokPos = f.Package
file := fset.File(f.Package)
pkgLine := file.Line(f.Package)
for _, c := range f.Comments {
if file.Line(c.Pos()) > pkgLine {
break
}
// +2 for a blank line
impDecl.TokPos = c.End() + 2
}
}
f.Decls = append(f.Decls, nil)
copy(f.Decls[lastImport+2:], f.Decls[lastImport+1:])
f.Decls[lastImport+1] = impDecl
}
// Insert new import at insertAt.
insertAt := 0
if impIndex >= 0 {
// insert after the found import
insertAt = impIndex + 1
}
impDecl.Specs = append(impDecl.Specs, nil)
copy(impDecl.Specs[insertAt+1:], impDecl.Specs[insertAt:])
impDecl.Specs[insertAt] = newImport
pos := impDecl.Pos()
if insertAt > 0 {
// If there is a comment after an existing import, preserve the comment
// position by adding the new import after the comment.
if spec, ok := impDecl.Specs[insertAt-1].(*ast.ImportSpec); ok && spec.Comment != nil {
pos = spec.Comment.End()
} else {
// Assign same position as the previous import,
// so that the sorter sees it as being in the same block.
pos = impDecl.Specs[insertAt-1].Pos()
}
}
if newImport.Name != nil {
newImport.Name.NamePos = pos
}
newImport.Path.ValuePos = pos
newImport.EndPos = pos
// Clean up parens. impDecl contains at least one spec.
if len(impDecl.Specs) == 1 {
// Remove unneeded parens.
impDecl.Lparen = token.NoPos
} else if !impDecl.Lparen.IsValid() {
// impDecl needs parens added.
impDecl.Lparen = impDecl.Specs[0].Pos()
}
f.Imports = append(f.Imports, newImport)
if len(f.Decls) <= 1 {
return true
}
// Merge all the import declarations into the first one.
var first *ast.GenDecl
for i := 0; i < len(f.Decls); i++ {
decl := f.Decls[i]
gen, ok := decl.(*ast.GenDecl)
if !ok || gen.Tok != token.IMPORT || declImports(gen, "C") {
continue
}
if first == nil {
first = gen
continue // Don't touch the first one.
}
// We now know there is more than one package in this import
// declaration. Ensure that it ends up parenthesized.
first.Lparen = first.Pos()
// Move the imports of the other import declaration to the first one.
for _, spec := range gen.Specs {
spec.(*ast.ImportSpec).Path.ValuePos = first.Pos()
first.Specs = append(first.Specs, spec)
}
f.Decls = append(f.Decls[:i], f.Decls[i+1:]...)
i--
}
return true
}
func isThirdParty(importPath string) bool {
// Third party package import path usually contains "." (".com", ".org", ...)
// This logic is taken from golang.org/x/tools/imports package.
return strings.Contains(importPath, ".")
}
// DeleteImport deletes the import path from the file f, if present.
func DeleteImport(fset *token.FileSet, f *ast.File, path string) (deleted bool) {
return DeleteNamedImport(fset, f, "", path)
}
// DeleteNamedImport deletes the import with the given name and path from the file f, if present.
func DeleteNamedImport(fset *token.FileSet, f *ast.File, name, path string) (deleted bool) {
var delspecs []*ast.ImportSpec
var delcomments []*ast.CommentGroup
// Find the import nodes that import path, if any.
for i := 0; i < len(f.Decls); i++ {
decl := f.Decls[i]
gen, ok := decl.(*ast.GenDecl)
if !ok || gen.Tok != token.IMPORT {
continue
}
for j := 0; j < len(gen.Specs); j++ {
spec := gen.Specs[j]
impspec := spec.(*ast.ImportSpec)
if impspec.Name == nil && name != "" {
continue
}
if impspec.Name != nil && impspec.Name.Name != name {
continue
}
if importPath(impspec) != path {
continue
}
// We found an import spec that imports path.
// Delete it.
delspecs = append(delspecs, impspec)
deleted = true
copy(gen.Specs[j:], gen.Specs[j+1:])
gen.Specs = gen.Specs[:len(gen.Specs)-1]
// If this was the last import spec in this decl,
// delete the decl, too.
if len(gen.Specs) == 0 {
copy(f.Decls[i:], f.Decls[i+1:])
f.Decls = f.Decls[:len(f.Decls)-1]
i--
break
} else if len(gen.Specs) == 1 {
if impspec.Doc != nil {
delcomments = append(delcomments, impspec.Doc)
}
if impspec.Comment != nil {
delcomments = append(delcomments, impspec.Comment)
}
for _, cg := range f.Comments {
// Found comment on the same line as the import spec.
if cg.End() < impspec.Pos() && fset.Position(cg.End()).Line == fset.Position(impspec.Pos()).Line {
delcomments = append(delcomments, cg)
break
}
}
spec := gen.Specs[0].(*ast.ImportSpec)
// Move the documentation right after the import decl.
if spec.Doc != nil {
for fset.Position(gen.TokPos).Line+1 < fset.Position(spec.Doc.Pos()).Line {
fset.File(gen.TokPos).MergeLine(fset.Position(gen.TokPos).Line)
}
}
for _, cg := range f.Comments {
if cg.End() < spec.Pos() && fset.Position(cg.End()).Line == fset.Position(spec.Pos()).Line {
for fset.Position(gen.TokPos).Line+1 < fset.Position(spec.Pos()).Line {
fset.File(gen.TokPos).MergeLine(fset.Position(gen.TokPos).Line)
}
break
}
}
}
if j > 0 {
lastImpspec := gen.Specs[j-1].(*ast.ImportSpec)
lastLine := fset.Position(lastImpspec.Path.ValuePos).Line
line := fset.Position(impspec.Path.ValuePos).Line
// We deleted an entry but now there may be
// a blank line-sized hole where the import was.
if line-lastLine > 1 {
// There was a blank line immediately preceding the deleted import,
// so there's no need to close the hole.
// Do nothing.
} else if line != fset.File(gen.Rparen).LineCount() {
// There was no blank line. Close the hole.
fset.File(gen.Rparen).MergeLine(line)
}
}
j--
}
}
// Delete imports from f.Imports.
for i := 0; i < len(f.Imports); i++ {
imp := f.Imports[i]
for j, del := range delspecs {
if imp == del {
copy(f.Imports[i:], f.Imports[i+1:])
f.Imports = f.Imports[:len(f.Imports)-1]
copy(delspecs[j:], delspecs[j+1:])
delspecs = delspecs[:len(delspecs)-1]
i--
break
}
}
}
// Delete comments from f.Comments.
for i := 0; i < len(f.Comments); i++ {
cg := f.Comments[i]
for j, del := range delcomments {
if cg == del {
copy(f.Comments[i:], f.Comments[i+1:])
f.Comments = f.Comments[:len(f.Comments)-1]
copy(delcomments[j:], delcomments[j+1:])
delcomments = delcomments[:len(delcomments)-1]
i--
break
}
}
}
if len(delspecs) > 0 {
panic(fmt.Sprintf("deleted specs from Decls but not Imports: %v", delspecs))
}
return
}
// RewriteImport rewrites any import of path oldPath to path newPath.
func RewriteImport(fset *token.FileSet, f *ast.File, oldPath, newPath string) (rewrote bool) {
for _, imp := range f.Imports {
if importPath(imp) == oldPath {
rewrote = true
// record old End, because the default is to compute
// it using the length of imp.Path.Value.
imp.EndPos = imp.End()
imp.Path.Value = strconv.Quote(newPath)
}
}
return
}
// UsesImport reports whether a given import is used.
func UsesImport(f *ast.File, path string) (used bool) {
spec := importSpec(f, path)
if spec == nil {
return
}
name := spec.Name.String()
switch name {
case "<nil>":
// If the package name is not explicitly specified,
// make an educated guess. This is not guaranteed to be correct.
lastSlash := strings.LastIndex(path, "/")
if lastSlash == -1 {
name = path
} else {
name = path[lastSlash+1:]
}
case "_", ".":
// Not sure if this import is used - err on the side of caution.
return true
}
ast.Walk(visitFn(func(n ast.Node) {
sel, ok := n.(*ast.SelectorExpr)
if ok && isTopName(sel.X, name) {
used = true
}
}), f)
return
}
type visitFn func(node ast.Node)
func (fn visitFn) Visit(node ast.Node) ast.Visitor {
fn(node)
return fn
}
// imports returns true if f imports path.
func imports(f *ast.File, path string) bool {
return importSpec(f, path) != nil
}
// importSpec returns the import spec if f imports path,
// or nil otherwise.
func importSpec(f *ast.File, path string) *ast.ImportSpec {
for _, s := range f.Imports {
if importPath(s) == path {
return s
}
}
return nil
}
// importPath returns the unquoted import path of s,
// or "" if the path is not properly quoted.
func importPath(s *ast.ImportSpec) string {
t, err := strconv.Unquote(s.Path.Value)
if err == nil {
return t
}
return ""
}
// declImports reports whether gen contains an import of path.
func declImports(gen *ast.GenDecl, path string) bool {
if gen.Tok != token.IMPORT {
return false
}
for _, spec := range gen.Specs {
impspec := spec.(*ast.ImportSpec)
if importPath(impspec) == path {
return true
}
}
return false
}
// matchLen returns the length of the longest path segment prefix shared by x and y.
func matchLen(x, y string) int {
n := 0
for i := 0; i < len(x) && i < len(y) && x[i] == y[i]; i++ {
if x[i] == '/' {
n++
}
}
return n
}
// isTopName returns true if n is a top-level unresolved identifier with the given name.
func isTopName(n ast.Expr, name string) bool {
id, ok := n.(*ast.Ident)
return ok && id.Name == name && id.Obj == nil
}
// Imports returns the file imports grouped by paragraph.
func Imports(fset *token.FileSet, f *ast.File) [][]*ast.ImportSpec {
var groups [][]*ast.ImportSpec
for _, decl := range f.Decls {
genDecl, ok := decl.(*ast.GenDecl)
if !ok || genDecl.Tok != token.IMPORT {
break
}
group := []*ast.ImportSpec{}
var lastLine int
for _, spec := range genDecl.Specs {
importSpec := spec.(*ast.ImportSpec)
pos := importSpec.Path.ValuePos
line := fset.Position(pos).Line
if lastLine > 0 && pos > 0 && line-lastLine > 1 {
groups = append(groups, group)
group = []*ast.ImportSpec{}
}
group = append(group, importSpec)
lastLine = line
}
groups = append(groups, group)
}
return groups
}
src/cmd/vendor/golang.org/x/tools/go/ast/astutil/rewrite.go 0 → 100644
View file @ 8b469209
// Copyright 2017 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
package astutil
import (
"fmt"
"go/ast"
"reflect"
"sort"
)
// An ApplyFunc is invoked by Apply for each node n, even if n is nil,
// before and/or after the node's children, using a Cursor describing
// the current node and providing operations on it.
//
// The return value of ApplyFunc controls the syntax tree traversal.
// See Apply for details.
type ApplyFunc func(*Cursor) bool
// Apply traverses a syntax tree recursively, starting with root,
// and calling pre and post for each node as described below.
// Apply returns the syntax tree, possibly modified.
//
// If pre is not nil, it is called for each node before the node's
// children are traversed (pre-order). If pre returns false, no
// children are traversed, and post is not called for that node.
//
// If post is not nil, and a prior call of pre didn't return false,
// post is called for each node after its children are traversed
// (post-order). If post returns false, traversal is terminated and
// Apply returns immediately.
//
// Only fields that refer to AST nodes are considered children;
// i.e., token.Pos, Scopes, Objects, and fields of basic types
// (strings, etc.) are ignored.
//
// Children are traversed in the order in which they appear in the
// respective node's struct definition. A package's files are
// traversed in the filenames' alphabetical order.
//
func Apply(root ast.Node, pre, post ApplyFunc) (result ast.Node) {
parent := &struct{ ast.Node }{root}
defer func() {
if r := recover(); r != nil && r != abort {
panic(r)
}
result = parent.Node
}()
a := &application{pre: pre, post: post}
a.apply(parent, "Node", nil, root)
return
}
var abort = new(int) // singleton, to signal termination of Apply
// A Cursor describes a node encountered during Apply.
// Information about the node and its parent is available
// from the Node, Parent, Name, and Index methods.
//
// If p is a variable of type and value of the current parent node
// c.Parent(), and f is the field identifier with name c.Name(),
// the following invariants hold:
//
// p.f == c.Node() if c.Index() < 0
// p.f[c.Index()] == c.Node() if c.Index() >= 0
//
// The methods Replace, Delete, InsertBefore, and InsertAfter
// can be used to change the AST without disrupting Apply.
type Cursor struct {
parent ast.Node
name string
iter *iterator // valid if non-nil
node ast.Node
}
// Node returns the current Node.
func (c *Cursor) Node() ast.Node { return c.node }
// Parent returns the parent of the current Node.
func (c *Cursor) Parent() ast.Node { return c.parent }
// Name returns the name of the parent Node field that contains the current Node.
// If the parent is a *ast.Package and the current Node is a *ast.File, Name returns
// the filename for the current Node.
func (c *Cursor) Name() string { return c.name }
// Index reports the index >= 0 of the current Node in the slice of Nodes that
// contains it, or a value < 0 if the current Node is not part of a slice.
// The index of the current node changes if InsertBefore is called while
// processing the current node.
func (c *Cursor) Index() int {
if c.iter != nil {
return c.iter.index
}
return -1
}
// field returns the current node's parent field value.
func (c *Cursor) field() reflect.Value {
return reflect.Indirect(reflect.ValueOf(c.parent)).FieldByName(c.name)
}
// Replace replaces the current Node with n.
// The replacement node is not walked by Apply.
func (c *Cursor) Replace(n ast.Node) {
if _, ok := c.node.(*ast.File); ok {
file, ok := n.(*ast.File)
if !ok {
panic("attempt to replace *ast.File with non-*ast.File")
}
c.parent.(*ast.Package).Files[c.name] = file
return
}
v := c.field()
if i := c.Index(); i >= 0 {
v = v.Index(i)
}
v.Set(reflect.ValueOf(n))
}
// Delete deletes the current Node from its containing slice.
// If the current Node is not part of a slice, Delete panics.
// As a special case, if the current node is a package file,
// Delete removes it from the package's Files map.
func (c *Cursor) Delete() {
if _, ok := c.node.(*ast.File); ok {
delete(c.parent.(*ast.Package).Files, c.name)
return
}
i := c.Index()
if i < 0 {
panic("Delete node not contained in slice")
}
v := c.field()
l := v.Len()
reflect.Copy(v.Slice(i, l), v.Slice(i+1, l))
v.Index(l - 1).Set(reflect.Zero(v.Type().Elem()))
v.SetLen(l - 1)
c.iter.step--
}
// InsertAfter inserts n after the current Node in its containing slice.
// If the current Node is not part of a slice, InsertAfter panics.
// Apply does not walk n.
func (c *Cursor) InsertAfter(n ast.Node) {
i := c.Index()
if i < 0 {
panic("InsertAfter node not contained in slice")
}
v := c.field()
v.Set(reflect.Append(v, reflect.Zero(v.Type().Elem())))
l := v.Len()
reflect.Copy(v.Slice(i+2, l), v.Slice(i+1, l))
v.Index(i + 1).Set(reflect.ValueOf(n))
c.iter.step++
}
// InsertBefore inserts n before the current Node in its containing slice.
// If the current Node is not part of a slice, InsertBefore panics.
// Apply will not walk n.
func (c *Cursor) InsertBefore(n ast.Node) {
i := c.Index()
if i < 0 {
panic("InsertBefore node not contained in slice")
}
v := c.field()
v.Set(reflect.Append(v, reflect.Zero(v.Type().Elem())))
l := v.Len()
reflect.Copy(v.Slice(i+1, l), v.Slice(i, l))
v.Index(i).Set(reflect.ValueOf(n))
c.iter.index++
}
// application carries all the shared data so we can pass it around cheaply.
type application struct {
pre, post ApplyFunc
cursor Cursor
iter iterator
}
func (a *application) apply(parent ast.Node, name string, iter *iterator, n ast.Node) {
// convert typed nil into untyped nil
if v := reflect.ValueOf(n); v.Kind() == reflect.Ptr && v.IsNil() {
n = nil
}
// avoid heap-allocating a new cursor for each apply call; reuse a.cursor instead
saved := a.cursor
a.cursor.parent = parent
a.cursor.name = name
a.cursor.iter = iter
a.cursor.node = n
if a.pre != nil && !a.pre(&a.cursor) {
a.cursor = saved
return
}
// walk children
// (the order of the cases matches the order of the corresponding node types in go/ast)
switch n := n.(type) {
case nil:
// nothing to do
// Comments and fields
case *ast.Comment:
// nothing to do
case *ast.CommentGroup:
if n != nil {
a.applyList(n, "List")
}
case *ast.Field:
a.apply(n, "Doc", nil, n.Doc)
a.applyList(n, "Names")
a.apply(n, "Type", nil, n.Type)
a.apply(n, "Tag", nil, n.Tag)
a.apply(n, "Comment", nil, n.Comment)
case *ast.FieldList:
a.applyList(n, "List")
// Expressions
case *ast.BadExpr, *ast.Ident, *ast.BasicLit:
// nothing to do
case *ast.Ellipsis:
a.apply(n, "Elt", nil, n.Elt)
case *ast.FuncLit:
a.apply(n, "Type", nil, n.Type)
a.apply(n, "Body", nil, n.Body)
case *ast.CompositeLit:
a.apply(n, "Type", nil, n.Type)
a.applyList(n, "Elts")
case *ast.ParenExpr:
a.apply(n, "X", nil, n.X)
case *ast.SelectorExpr:
a.apply(n, "X", nil, n.X)
a.apply(n, "Sel", nil, n.Sel)
case *ast.IndexExpr:
a.apply(n, "X", nil, n.X)
a.apply(n, "Index", nil, n.Index)
case *ast.SliceExpr:
a.apply(n, "X", nil, n.X)
a.apply(n, "Low", nil, n.Low)
a.apply(n, "High", nil, n.High)
a.apply(n, "Max", nil, n.Max)
case *ast.TypeAssertExpr:
a.apply(n, "X", nil, n.X)
a.apply(n, "Type", nil, n.Type)
case *ast.CallExpr:
a.apply(n, "Fun", nil, n.Fun)
a.applyList(n, "Args")
case *ast.StarExpr:
a.apply(n, "X", nil, n.X)
case *ast.UnaryExpr:
a.apply(n, "X", nil, n.X)
case *ast.BinaryExpr:
a.apply(n, "X", nil, n.X)
a.apply(n, "Y", nil, n.Y)
case *ast.KeyValueExpr:
a.apply(n, "Key", nil, n.Key)
a.apply(n, "Value", nil, n.Value)
// Types
case *ast.ArrayType:
a.apply(n, "Len", nil, n.Len)
a.apply(n, "Elt", nil, n.Elt)
case *ast.StructType:
a.apply(n, "Fields", nil, n.Fields)
case *ast.FuncType:
a.apply(n, "Params", nil, n.Params)
a.apply(n, "Results", nil, n.Results)
case *ast.InterfaceType:
a.apply(n, "Methods", nil, n.Methods)
case *ast.MapType:
a.apply(n, "Key", nil, n.Key)
a.apply(n, "Value", nil, n.Value)
case *ast.ChanType:
a.apply(n, "Value", nil, n.Value)
// Statements
case *ast.BadStmt:
// nothing to do
case *ast.DeclStmt:
a.apply(n, "Decl", nil, n.Decl)
case *ast.EmptyStmt:
// nothing to do
case *ast.LabeledStmt:
a.apply(n, "Label", nil, n.Label)
a.apply(n, "Stmt", nil, n.Stmt)
case *ast.ExprStmt:
a.apply(n, "X", nil, n.X)
case *ast.SendStmt:
a.apply(n, "Chan", nil, n.Chan)
a.apply(n, "Value", nil, n.Value)
case *ast.IncDecStmt:
a.apply(n, "X", nil, n.X)
case *ast.AssignStmt:
a.applyList(n, "Lhs")
a.applyList(n, "Rhs")
case *ast.GoStmt:
a.apply(n, "Call", nil, n.Call)
case *ast.DeferStmt:
a.apply(n, "Call", nil, n.Call)
case *ast.ReturnStmt:
a.applyList(n, "Results")
case *ast.BranchStmt:
a.apply(n, "Label", nil, n.Label)
case *ast.BlockStmt:
a.applyList(n, "List")
case *ast.IfStmt:
a.apply(n, "Init", nil, n.Init)
a.apply(n, "Cond", nil, n.Cond)
a.apply(n, "Body", nil, n.Body)
a.apply(n, "Else", nil, n.Else)
case *ast.CaseClause:
a.applyList(n, "List")
a.applyList(n, "Body")
case *ast.SwitchStmt:
a.apply(n, "Init", nil, n.Init)
a.apply(n, "Tag", nil, n.Tag)
a.apply(n, "Body", nil, n.Body)
case *ast.TypeSwitchStmt:
a.apply(n, "Init", nil, n.Init)
a.apply(n, "Assign", nil, n.Assign)
a.apply(n, "Body", nil, n.Body)
case *ast.CommClause:
a.apply(n, "Comm", nil, n.Comm)
a.applyList(n, "Body")
case *ast.SelectStmt:
a.apply(n, "Body", nil, n.Body)
case *ast.ForStmt:
a.apply(n, "Init", nil, n.Init)
a.apply(n, "Cond", nil, n.Cond)
a.apply(n, "Post", nil, n.Post)
a.apply(n, "Body", nil, n.Body)
case *ast.RangeStmt:
a.apply(n, "Key", nil, n.Key)
a.apply(n, "Value", nil, n.Value)
a.apply(n, "X", nil, n.X)
a.apply(n, "Body", nil, n.Body)
// Declarations
case *ast.ImportSpec:
a.apply(n, "Doc", nil, n.Doc)
a.apply(n, "Name", nil, n.Name)
a.apply(n, "Path", nil, n.Path)
a.apply(n, "Comment", nil, n.Comment)
case *ast.ValueSpec:
a.apply(n, "Doc", nil, n.Doc)
a.applyList(n, "Names")
a.apply(n, "Type", nil, n.Type)
a.applyList(n, "Values")
a.apply(n, "Comment", nil, n.Comment)
case *ast.TypeSpec:
a.apply(n, "Doc", nil, n.Doc)
a.apply(n, "Name", nil, n.Name)
a.apply(n, "Type", nil, n.Type)
a.apply(n, "Comment", nil, n.Comment)
case *ast.BadDecl:
// nothing to do
case *ast.GenDecl:
a.apply(n, "Doc", nil, n.Doc)
a.applyList(n, "Specs")
case *ast.FuncDecl:
a.apply(n, "Doc", nil, n.Doc)
a.apply(n, "Recv", nil, n.Recv)
a.apply(n, "Name", nil, n.Name)
a.apply(n, "Type", nil, n.Type)
a.apply(n, "Body", nil, n.Body)
// Files and packages
case *ast.File:
a.apply(n, "Doc", nil, n.Doc)
a.apply(n, "Name", nil, n.Name)
a.applyList(n, "Decls")
// Don't walk n.Comments; they have either been walked already if
// they are Doc comments, or they can be easily walked explicitly.
case *ast.Package:
// collect and sort names for reproducible behavior
var names []string
for name := range n.Files {
names = append(names, name)
}
sort.Strings(names)
for _, name := range names {
a.apply(n, name, nil, n.Files[name])
}
default:
panic(fmt.Sprintf("Apply: unexpected node type %T", n))
}
if a.post != nil && !a.post(&a.cursor) {
panic(abort)
}
a.cursor = saved
}
// An iterator controls iteration over a slice of nodes.
type iterator struct {
index, step int
}
func (a *application) applyList(parent ast.Node, name string) {
// avoid heap-allocating a new iterator for each applyList call; reuse a.iter instead
saved := a.iter
a.iter.index = 0
for {
// must reload parent.name each time, since cursor modifications might change it
v := reflect.Indirect(reflect.ValueOf(parent)).FieldByName(name)
if a.iter.index >= v.Len() {
break
}
// element x may be nil in a bad AST - be cautious
var x ast.Node
if e := v.Index(a.iter.index); e.IsValid() {
x = e.Interface().(ast.Node)
}
a.iter.step = 1
a.apply(parent, name, &a.iter, x)
a.iter.index += a.iter.step
}
a.iter = saved
}
src/cmd/vendor/golang.org/x/tools/go/ast/astutil/util.go 0 → 100644
View file @ 8b469209
package astutil
import "go/ast"
// Unparen returns e with any enclosing parentheses stripped.
func Unparen(e ast.Expr) ast.Expr {
for {
p, ok := e.(*ast.ParenExpr)
if !ok {
return e
}
e = p.X
}
}
src/cmd/vendor/golang.org/x/tools/go/ast/inspector/inspector.go 0 → 100644
View file @ 8b469209
// Copyright 2018 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
// Package inspector provides helper functions for traversal over the
// syntax trees of a package, including node filtering by type, and
// materialization of the traversal stack.
//
// During construction, the inspector does a complete traversal and
// builds a list of push/pop events and their node type. Subsequent
// method calls that request a traversal scan this list, rather than walk
// the AST, and perform type filtering using efficient bit sets.
//
// Experiments suggest the inspector's traversals are about 2.5x faster
// than ast.Inspect, but it may take around 5 traversals for this
// benefit to amortize the inspector's construction cost.
// If efficiency is the primary concern, do not use use Inspector for
// one-off traversals.
package inspector
// There are four orthogonal features in a traversal:
// 1 type filtering
// 2 pruning
// 3 postorder calls to f
// 4 stack
// Rather than offer all of them in the API,
// only a few combinations are exposed:
// - Preorder is the fastest and has fewest features,
// but is the most commonly needed traversal.
// - Nodes and WithStack both provide pruning and postorder calls,
// even though few clients need it, because supporting two versions
// is not justified.
// More combinations could be supported by expressing them as
// wrappers around a more generic traversal, but this was measured
// and found to degrade performance significantly (30%).
import (
"go/ast"
)
// An Inspector provides methods for inspecting
// (traversing) the syntax trees of a package.
type Inspector struct {
events []event
}
// New returns an Inspector for the specified syntax trees.
func New(files []*ast.File) *Inspector {
return &Inspector{traverse(files)}
}
// An event represents a push or a pop
// of an ast.Node during a traversal.
type event struct {
node ast.Node
typ uint64 // typeOf(node)
index int // 1 + index of corresponding pop event, or 0 if this is a pop
}
// Preorder visits all the nodes of the files supplied to New in
// depth-first order. It calls f(n) for each node n before it visits
// n's children.
//
// The types argument, if non-empty, enables type-based filtering of
// events. The function f if is called only for nodes whose type
// matches an element of the types slice.
func (in *Inspector) Preorder(types []ast.Node, f func(ast.Node)) {
// Because it avoids postorder calls to f, and the pruning
// check, Preorder is almost twice as fast as Nodes. The two
// features seem to contribute similar slowdowns (~1.4x each).
mask := maskOf(types)
for i := 0; i < len(in.events); {
ev := in.events[i]
if ev.typ&mask != 0 {
if ev.index > 0 {
f(ev.node)
}
}
i++
}
}
// Nodes visits the nodes of the files supplied to New in depth-first
// order. It calls f(n, true) for each node n before it visits n's
// children. If f returns true, Nodes invokes f recursively for each
// of the non-nil children of the node, followed by a call of
// f(n, false).
//
// The types argument, if non-empty, enables type-based filtering of
// events. The function f if is called only for nodes whose type
// matches an element of the types slice.
func (in *Inspector) Nodes(types []ast.Node, f func(n ast.Node, push bool) (prune bool)) {
mask := maskOf(types)
for i := 0; i < len(in.events); {
ev := in.events[i]
if ev.typ&mask != 0 {
if ev.index > 0 {
// push
if !f(ev.node, true) {
i = ev.index // jump to corresponding pop + 1
continue
}
} else {
// pop
f(ev.node, false)
}
}
i++
}
}
// WithStack visits nodes in a similar manner to Nodes, but it
// supplies each call to f an additional argument, the current
// traversal stack. The stack's first element is the outermost node,
// an *ast.File; its last is the innermost, n.
func (in *Inspector) WithStack(types []ast.Node, f func(n ast.Node, push bool, stack []ast.Node) (prune bool)) {
mask := maskOf(types)
var stack []ast.Node
for i := 0; i < len(in.events); {
ev := in.events[i]
if ev.index > 0 {
// push
stack = append(stack, ev.node)
if ev.typ&mask != 0 {
if !f(ev.node, true, stack) {
i = ev.index
stack = stack[:len(stack)-1]
continue
}
}
} else {
// pop
if ev.typ&mask != 0 {
f(ev.node, false, stack)
}
stack = stack[:len(stack)-1]
}
i++
}
}
// traverse builds the table of events representing a traversal.
func traverse(files []*ast.File) []event {
// Preallocate approximate number of events
// based on source file extent.
// This makes traverse faster by 4x (!).
var extent int
for _, f := range files {
extent += int(f.End() - f.Pos())
}
// This estimate is based on the net/http package.
events := make([]event, 0, extent*33/100)
var stack []event
for _, f := range files {
ast.Inspect(f, func(n ast.Node) bool {
if n != nil {
// push
ev := event{
node: n,
typ: typeOf(n),
index: len(events), // push event temporarily holds own index
}
stack = append(stack, ev)
events = append(events, ev)
} else {
// pop
ev := stack[len(stack)-1]
stack = stack[:len(stack)-1]
events[ev.index].index = len(events) + 1 // make push refer to pop
ev.index = 0 // turn ev into a pop event
events = append(events, ev)
}
return true
})
}
return events
}
src/cmd/vendor/golang.org/x/tools/go/ast/inspector/typeof.go 0 → 100644
View file @ 8b469209
package inspector
// This file defines func typeOf(ast.Node) uint64.
//
// The initial map-based implementation was too slow;
// see https://go-review.googlesource.com/c/tools/+/135655/1/go/ast/inspector/inspector.go#196
import "go/ast"
const (
nArrayType = iota
nAssignStmt
nBadDecl
nBadExpr
nBadStmt
nBasicLit
nBinaryExpr
nBlockStmt
nBranchStmt
nCallExpr
nCaseClause
nChanType
nCommClause
nComment
nCommentGroup
nCompositeLit
nDeclStmt
nDeferStmt
nEllipsis
nEmptyStmt
nExprStmt
nField
nFieldList
nFile
nForStmt
nFuncDecl
nFuncLit
nFuncType
nGenDecl
nGoStmt
nIdent
nIfStmt
nImportSpec
nIncDecStmt
nIndexExpr
nInterfaceType
nKeyValueExpr
nLabeledStmt
nMapType
nPackage
nParenExpr
nRangeStmt
nReturnStmt
nSelectStmt
nSelectorExpr
nSendStmt
nSliceExpr
nStarExpr
nStructType
nSwitchStmt
nTypeAssertExpr
nTypeSpec
nTypeSwitchStmt
nUnaryExpr
nValueSpec
)
// typeOf returns a distinct single-bit value that represents the type of n.
//
// Various implementations were benchmarked with BenchmarkNewInspector:
// GOGC=off
// - type switch 4.9-5.5ms 2.1ms
// - binary search over a sorted list of types 5.5-5.9ms 2.5ms
// - linear scan, frequency-ordered list 5.9-6.1ms 2.7ms
// - linear scan, unordered list 6.4ms 2.7ms
// - hash table 6.5ms 3.1ms
// A perfect hash seemed like overkill.
//
// The compiler's switch statement is the clear winner
// as it produces a binary tree in code,
// with constant conditions and good branch prediction.
// (Sadly it is the most verbose in source code.)
// Binary search suffered from poor branch prediction.
//
func typeOf(n ast.Node) uint64 {
// Fast path: nearly half of all nodes are identifiers.
if _, ok := n.(*ast.Ident); ok {
return 1 << nIdent
}
// These cases include all nodes encountered by ast.Inspect.
switch n.(type) {
case *ast.ArrayType:
return 1 << nArrayType
case *ast.AssignStmt:
return 1 << nAssignStmt
case *ast.BadDecl:
return 1 << nBadDecl
case *ast.BadExpr:
return 1 << nBadExpr
case *ast.BadStmt:
return 1 << nBadStmt
case *ast.BasicLit:
return 1 << nBasicLit
case *ast.BinaryExpr:
return 1 << nBinaryExpr
case *ast.BlockStmt:
return 1 << nBlockStmt
case *ast.BranchStmt:
return 1 << nBranchStmt
case *ast.CallExpr:
return 1 << nCallExpr
case *ast.CaseClause:
return 1 << nCaseClause
case *ast.ChanType:
return 1 << nChanType
case *ast.CommClause:
return 1 << nCommClause
case *ast.Comment:
return 1 << nComment
case *ast.CommentGroup:
return 1 << nCommentGroup
case *ast.CompositeLit:
return 1 << nCompositeLit
case *ast.DeclStmt:
return 1 << nDeclStmt
case *ast.DeferStmt:
return 1 << nDeferStmt
case *ast.Ellipsis:
return 1 << nEllipsis
case *ast.EmptyStmt:
return 1 << nEmptyStmt
case *ast.ExprStmt:
return 1 << nExprStmt
case *ast.Field:
return 1 << nField
case *ast.FieldList:
return 1 << nFieldList
case *ast.File:
return 1 << nFile
case *ast.ForStmt:
return 1 << nForStmt
case *ast.FuncDecl:
return 1 << nFuncDecl
case *ast.FuncLit:
return 1 << nFuncLit
case *ast.FuncType:
return 1 << nFuncType
case *ast.GenDecl:
return 1 << nGenDecl
case *ast.GoStmt:
return 1 << nGoStmt
case *ast.Ident:
return 1 << nIdent
case *ast.IfStmt:
return 1 << nIfStmt
case *ast.ImportSpec:
return 1 << nImportSpec
case *ast.IncDecStmt:
return 1 << nIncDecStmt
case *ast.IndexExpr:
return 1 << nIndexExpr
case *ast.InterfaceType:
return 1 << nInterfaceType
case *ast.KeyValueExpr:
return 1 << nKeyValueExpr
case *ast.LabeledStmt:
return 1 << nLabeledStmt
case *ast.MapType:
return 1 << nMapType
case *ast.Package:
return 1 << nPackage
case *ast.ParenExpr:
return 1 << nParenExpr
case *ast.RangeStmt:
return 1 << nRangeStmt
case *ast.ReturnStmt:
return 1 << nReturnStmt
case *ast.SelectStmt:
return 1 << nSelectStmt
case *ast.SelectorExpr:
return 1 << nSelectorExpr
case *ast.SendStmt:
return 1 << nSendStmt
case *ast.SliceExpr:
return 1 << nSliceExpr
case *ast.StarExpr:
return 1 << nStarExpr
case *ast.StructType:
return 1 << nStructType
case *ast.SwitchStmt:
return 1 << nSwitchStmt
case *ast.TypeAssertExpr:
return 1 << nTypeAssertExpr
case *ast.TypeSpec:
return 1 << nTypeSpec
case *ast.TypeSwitchStmt:
return 1 << nTypeSwitchStmt
case *ast.UnaryExpr:
return 1 << nUnaryExpr
case *ast.ValueSpec:
return 1 << nValueSpec
}
return 0
}
func maskOf(nodes []ast.Node) uint64 {
if nodes == nil {
return 1<<64 - 1 // match all node types
}
var mask uint64
for _, n := range nodes {
mask |= typeOf(n)
}
return mask
}
src/cmd/vendor/golang.org/x/tools/go/cfg/builder.go 0 → 100644
View file @ 8b469209
// Copyright 2016 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
package cfg
// This file implements the CFG construction pass.
import (
"fmt"
"go/ast"
"go/token"
)
type builder struct {
cfg *CFG
mayReturn func(*ast.CallExpr) bool
current *Block
lblocks map[*ast.Object]*lblock // labeled blocks
targets *targets // linked stack of branch targets
}
func (b *builder) stmt(_s ast.Stmt) {
// The label of the current statement. If non-nil, its _goto
// target is always set; its _break and _continue are set only
// within the body of switch/typeswitch/select/for/range.
// It is effectively an additional default-nil parameter of stmt().
var label *lblock
start:
switch s := _s.(type) {
case *ast.BadStmt,
*ast.SendStmt,
*ast.IncDecStmt,
*ast.GoStmt,
*ast.DeferStmt,
*ast.EmptyStmt,
*ast.AssignStmt:
// No effect on control flow.
b.add(s)
case *ast.ExprStmt:
b.add(s)
if call, ok := s.X.(*ast.CallExpr); ok && !b.mayReturn(call) {
// Calls to panic, os.Exit, etc, never return.
b.current = b.newBlock("unreachable.call")
}
case *ast.DeclStmt:
// Treat each var ValueSpec as a separate statement.
d := s.Decl.(*ast.GenDecl)
if d.Tok == token.VAR {
for _, spec := range d.Specs {
if spec, ok := spec.(*ast.ValueSpec); ok {
b.add(spec)
}
}
}
case *ast.LabeledStmt:
label = b.labeledBlock(s.Label)
b.jump(label._goto)
b.current = label._goto
_s = s.Stmt
goto start // effectively: tailcall stmt(g, s.Stmt, label)
case *ast.ReturnStmt:
b.add(s)
b.current = b.newBlock("unreachable.return")
case *ast.BranchStmt:
b.branchStmt(s)
case *ast.BlockStmt:
b.stmtList(s.List)
case *ast.IfStmt:
if s.Init != nil {
b.stmt(s.Init)
}
then := b.newBlock("if.then")
done := b.newBlock("if.done")
_else := done
if s.Else != nil {
_else = b.newBlock("if.else")
}
b.add(s.Cond)
b.ifelse(then, _else)
b.current = then
b.stmt(s.Body)
b.jump(done)
if s.Else != nil {
b.current = _else
b.stmt(s.Else)
b.jump(done)
}
b.current = done
case *ast.SwitchStmt:
b.switchStmt(s, label)
case *ast.TypeSwitchStmt:
b.typeSwitchStmt(s, label)
case *ast.SelectStmt:
b.selectStmt(s, label)
case *ast.ForStmt:
b.forStmt(s, label)
case *ast.RangeStmt:
b.rangeStmt(s, label)
default:
panic(fmt.Sprintf("unexpected statement kind: %T", s))
}
}
func (b *builder) stmtList(list []ast.Stmt) {
for _, s := range list {
b.stmt(s)
}
}
func (b *builder) branchStmt(s *ast.BranchStmt) {
var block *Block
switch s.Tok {
case token.BREAK:
if s.Label != nil {
if lb := b.labeledBlock(s.Label); lb != nil {
block = lb._break
}
} else {
for t := b.targets; t != nil && block == nil; t = t.tail {
block = t._break
}
}
case token.CONTINUE:
if s.Label != nil {
if lb := b.labeledBlock(s.Label); lb != nil {
block = lb._continue
}
} else {
for t := b.targets; t != nil && block == nil; t = t.tail {
block = t._continue
}
}
case token.FALLTHROUGH:
for t := b.targets; t != nil; t = t.tail {
block = t._fallthrough
}
case token.GOTO:
if s.Label != nil {
block = b.labeledBlock(s.Label)._goto
}
}
if block == nil {
block = b.newBlock("undefined.branch")
}
b.jump(block)
b.current = b.newBlock("unreachable.branch")
}
func (b *builder) switchStmt(s *ast.SwitchStmt, label *lblock) {
if s.Init != nil {
b.stmt(s.Init)
}
if s.Tag != nil {
b.add(s.Tag)
}
done := b.newBlock("switch.done")
if label != nil {
label._break = done
}
// We pull the default case (if present) down to the end.
// But each fallthrough label must point to the next
// body block in source order, so we preallocate a
// body block (fallthru) for the next case.
// Unfortunately this makes for a confusing block order.
var defaultBody *[]ast.Stmt
var defaultFallthrough *Block
var fallthru, defaultBlock *Block
ncases := len(s.Body.List)
for i, clause := range s.Body.List {
body := fallthru
if body == nil {
body = b.newBlock("switch.body") // first case only
}
// Preallocate body block for the next case.
fallthru = done
if i+1 < ncases {
fallthru = b.newBlock("switch.body")
}
cc := clause.(*ast.CaseClause)
if cc.List == nil {
// Default case.
defaultBody = &cc.Body
defaultFallthrough = fallthru
defaultBlock = body
continue
}
var nextCond *Block
for _, cond := range cc.List {
nextCond = b.newBlock("switch.next")
b.add(cond) // one half of the tag==cond condition
b.ifelse(body, nextCond)
b.current = nextCond
}
b.current = body
b.targets = &targets{
tail: b.targets,
_break: done,
_fallthrough: fallthru,
}
b.stmtList(cc.Body)
b.targets = b.targets.tail
b.jump(done)
b.current = nextCond
}
if defaultBlock != nil {
b.jump(defaultBlock)
b.current = defaultBlock
b.targets = &targets{
tail: b.targets,
_break: done,
_fallthrough: defaultFallthrough,
}
b.stmtList(*defaultBody)
b.targets = b.targets.tail
}
b.jump(done)
b.current = done
}
func (b *builder) typeSwitchStmt(s *ast.TypeSwitchStmt, label *lblock) {
if s.Init != nil {
b.stmt(s.Init)
}
if s.Assign != nil {
b.add(s.Assign)
}
done := b.newBlock("typeswitch.done")
if label != nil {
label._break = done
}
var default_ *ast.CaseClause
for _, clause := range s.Body.List {
cc := clause.(*ast.CaseClause)
if cc.List == nil {
default_ = cc
continue
}
body := b.newBlock("typeswitch.body")
var next *Block
for _, casetype := range cc.List {
next = b.newBlock("typeswitch.next")
// casetype is a type, so don't call b.add(casetype).
// This block logically contains a type assertion,
// x.(casetype), but it's unclear how to represent x.
_ = casetype
b.ifelse(body, next)
b.current = next
}
b.current = body
b.typeCaseBody(cc, done)
b.current = next
}
if default_ != nil {
b.typeCaseBody(default_, done)
} else {
b.jump(done)
}
b.current = done
}
func (b *builder) typeCaseBody(cc *ast.CaseClause, done *Block) {
b.targets = &targets{
tail: b.targets,
_break: done,
}
b.stmtList(cc.Body)
b.targets = b.targets.tail
b.jump(done)
}
func (b *builder) selectStmt(s *ast.SelectStmt, label *lblock) {
// First evaluate channel expressions.
// TODO(adonovan): fix: evaluate only channel exprs here.
for _, clause := range s.Body.List {
if comm := clause.(*ast.CommClause).Comm; comm != nil {
b.stmt(comm)
}
}
done := b.newBlock("select.done")
if label != nil {
label._break = done
}
var defaultBody *[]ast.Stmt
for _, cc := range s.Body.List {
clause := cc.(*ast.CommClause)
if clause.Comm == nil {
defaultBody = &clause.Body
continue
}
body := b.newBlock("select.body")
next := b.newBlock("select.next")
b.ifelse(body, next)
b.current = body
b.targets = &targets{
tail: b.targets,
_break: done,
}
switch comm := clause.Comm.(type) {
case *ast.ExprStmt: // <-ch
// nop
case *ast.AssignStmt: // x := <-states[state].Chan
b.add(comm.Lhs[0])
}
b.stmtList(clause.Body)
b.targets = b.targets.tail
b.jump(done)
b.current = next
}
if defaultBody != nil {
b.targets = &targets{
tail: b.targets,
_break: done,
}
b.stmtList(*defaultBody)
b.targets = b.targets.tail
b.jump(done)
}
b.current = done
}
func (b *builder) forStmt(s *ast.ForStmt, label *lblock) {
// ...init...
// jump loop
// loop:
// if cond goto body else done
// body:
// ...body...
// jump post
// post: (target of continue)
// ...post...
// jump loop
// done: (target of break)
if s.Init != nil {
b.stmt(s.Init)
}
body := b.newBlock("for.body")
done := b.newBlock("for.done") // target of 'break'
loop := body // target of back-edge
if s.Cond != nil {
loop = b.newBlock("for.loop")
}
cont := loop // target of 'continue'
if s.Post != nil {
cont = b.newBlock("for.post")
}
if label != nil {
label._break = done
label._continue = cont
}
b.jump(loop)
b.current = loop
if loop != body {
b.add(s.Cond)
b.ifelse(body, done)
b.current = body
}
b.targets = &targets{
tail: b.targets,
_break: done,
_continue: cont,
}
b.stmt(s.Body)
b.targets = b.targets.tail
b.jump(cont)
if s.Post != nil {
b.current = cont
b.stmt(s.Post)
b.jump(loop) // back-edge
}
b.current = done
}
func (b *builder) rangeStmt(s *ast.RangeStmt, label *lblock) {
b.add(s.X)
if s.Key != nil {
b.add(s.Key)
}
if s.Value != nil {
b.add(s.Value)
}
// ...
// loop: (target of continue)
// if ... goto body else done
// body:
// ...
// jump loop
// done: (target of break)
loop := b.newBlock("range.loop")
b.jump(loop)
b.current = loop
body := b.newBlock("range.body")
done := b.newBlock("range.done")
b.ifelse(body, done)
b.current = body
if label != nil {
label._break = done
label._continue = loop
}
b.targets = &targets{
tail: b.targets,
_break: done,
_continue: loop,
}
b.stmt(s.Body)
b.targets = b.targets.tail
b.jump(loop) // back-edge
b.current = done
}
// -------- helpers --------
// Destinations associated with unlabeled for/switch/select stmts.
// We push/pop one of these as we enter/leave each construct and for
// each BranchStmt we scan for the innermost target of the right type.
//
type targets struct {
tail *targets // rest of stack
_break *Block
_continue *Block
_fallthrough *Block
}
// Destinations associated with a labeled block.
// We populate these as labels are encountered in forward gotos or
// labeled statements.
//
type lblock struct {
_goto *Block
_break *Block
_continue *Block
}
// labeledBlock returns the branch target associated with the
// specified label, creating it if needed.
//
func (b *builder) labeledBlock(label *ast.Ident) *lblock {
lb := b.lblocks[label.Obj]
if lb == nil {
lb = &lblock{_goto: b.newBlock(label.Name)}
if b.lblocks == nil {
b.lblocks = make(map[*ast.Object]*lblock)
}
b.lblocks[label.Obj] = lb
}
return lb
}
// newBlock appends a new unconnected basic block to b.cfg's block
// slice and returns it.
// It does not automatically become the current block.
// comment is an optional string for more readable debugging output.
func (b *builder) newBlock(comment string) *Block {
g := b.cfg
block := &Block{
Index: int32(len(g.Blocks)),
comment: comment,
}
block.Succs = block.succs2[:0]
g.Blocks = append(g.Blocks, block)
return block
}
func (b *builder) add(n ast.Node) {
b.current.Nodes = append(b.current.Nodes, n)
}
// jump adds an edge from the current block to the target block,
// and sets b.current to nil.
func (b *builder) jump(target *Block) {
b.current.Succs = append(b.current.Succs, target)
b.current = nil
}
// ifelse emits edges from the current block to the t and f blocks,
// and sets b.current to nil.
func (b *builder) ifelse(t, f *Block) {
b.current.Succs = append(b.current.Succs, t, f)
b.current = nil
}
src/cmd/vendor/golang.org/x/tools/go/cfg/cfg.go 0 → 100644
View file @ 8b469209
// Copyright 2016 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
// This package constructs a simple control-flow graph (CFG) of the
// statements and expressions within a single function.
//
// Use cfg.New to construct the CFG for a function body.
//
// The blocks of the CFG contain all the function's non-control
// statements. The CFG does not contain control statements such as If,
// Switch, Select, and Branch, but does contain their subexpressions.
// For example, this source code:
//
// if x := f(); x != nil {
// T()
// } else {
// F()
// }
//
// produces this CFG:
//
// 1: x := f()
// x != nil
// succs: 2, 3
// 2: T()
// succs: 4
// 3: F()
// succs: 4
// 4:
//
// The CFG does contain Return statements; even implicit returns are
// materialized (at the position of the function's closing brace).
//
// The CFG does not record conditions associated with conditional branch
// edges, nor the short-circuit semantics of the && and || operators,
// nor abnormal control flow caused by panic. If you need this
// information, use golang.org/x/tools/go/ssa instead.
//
package cfg
import (
"bytes"
"fmt"
"go/ast"
"go/format"
"go/token"
)
// A CFG represents the control-flow graph of a single function.
//
// The entry point is Blocks[0]; there may be multiple return blocks.
type CFG struct {
Blocks []*Block // block[0] is entry; order otherwise undefined
}
// A Block represents a basic block: a list of statements and
// expressions that are always evaluated sequentially.
//
// A block may have 0-2 successors: zero for a return block or a block
// that calls a function such as panic that never returns; one for a
// normal (jump) block; and two for a conditional (if) block.
type Block struct {
Nodes []ast.Node // statements, expressions, and ValueSpecs
Succs []*Block // successor nodes in the graph
Index int32 // index within CFG.Blocks
Live bool // block is reachable from entry
comment string // for debugging
succs2 [2]*Block // underlying array for Succs
}
// New returns a new control-flow graph for the specified function body,
// which must be non-nil.
//
// The CFG builder calls mayReturn to determine whether a given function
// call may return. For example, calls to panic, os.Exit, and log.Fatal
// do not return, so the builder can remove infeasible graph edges
// following such calls. The builder calls mayReturn only for a
// CallExpr beneath an ExprStmt.
func New(body *ast.BlockStmt, mayReturn func(*ast.CallExpr) bool) *CFG {
b := builder{
mayReturn: mayReturn,
cfg: new(CFG),
}
b.current = b.newBlock("entry")
b.stmt(body)
// Compute liveness (reachability from entry point), breadth-first.
q := make([]*Block, 0, len(b.cfg.Blocks))
q = append(q, b.cfg.Blocks[0]) // entry point
for len(q) > 0 {
b := q[len(q)-1]
q = q[:len(q)-1]
if !b.Live {
b.Live = true
q = append(q, b.Succs...)
}
}
// Does control fall off the end of the function's body?
// Make implicit return explicit.
if b.current != nil && b.current.Live {
b.add(&ast.ReturnStmt{
Return: body.End() - 1,
})
}
return b.cfg
}
func (b *Block) String() string {
return fmt.Sprintf("block %d (%s)", b.Index, b.comment)
}
// Return returns the return statement at the end of this block if present, nil otherwise.
func (b *Block) Return() (ret *ast.ReturnStmt) {
if len(b.Nodes) > 0 {
ret, _ = b.Nodes[len(b.Nodes)-1].(*ast.ReturnStmt)
}
return
}
// Format formats the control-flow graph for ease of debugging.
func (g *CFG) Format(fset *token.FileSet) string {
var buf bytes.Buffer
for _, b := range g.Blocks {
fmt.Fprintf(&buf, ".%d: # %s\n", b.Index, b.comment)
for _, n := range b.Nodes {
fmt.Fprintf(&buf, "\t%s\n", formatNode(fset, n))
}
if len(b.Succs) > 0 {
fmt.Fprintf(&buf, "\tsuccs:")
for _, succ := range b.Succs {
fmt.Fprintf(&buf, " %d", succ.Index)
}
buf.WriteByte('\n')
}
buf.WriteByte('\n')
}
return buf.String()
}
func formatNode(fset *token.FileSet, n ast.Node) string {
var buf bytes.Buffer
format.Node(&buf, fset, n)
// Indent secondary lines by a tab.
return string(bytes.Replace(buf.Bytes(), []byte("\n"), []byte("\n\t"), -1))
}
src/cmd/vendor/golang.org/x/tools/go/types/objectpath/objectpath.go 0 → 100644
View file @ 8b469209
// Copyright 2018 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
// Package objectpath defines a naming scheme for types.Objects
// (that is, named entities in Go programs) relative to their enclosing
// package.
//
// Type-checker objects are canonical, so they are usually identified by
// their address in memory (a pointer), but a pointer has meaning only
// within one address space. By contrast, objectpath names allow the
// identity of an object to be sent from one program to another,
// establishing a correspondence between types.Object variables that are
// distinct but logically equivalent.
//
// A single object may have multiple paths. In this example,
// type A struct{ X int }
// type B A
// the field X has two paths due to its membership of both A and B.
// The For(obj) function always returns one of these paths, arbitrarily
// but consistently.
package objectpath
import (
"fmt"
"strconv"
"strings"
"go/types"
)
// A Path is an opaque name that identifies a types.Object
// relative to its package. Conceptually, the name consists of a
// sequence of destructuring operations applied to the package scope
// to obtain the original object.
// The name does not include the package itself.
type Path string
// Encoding
//
// An object path is a textual and (with training) human-readable encoding
// of a sequence of destructuring operators, starting from a types.Package.
// The sequences represent a path through the package/object/type graph.
// We classify these operators by their type:
//
// PO package->object Package.Scope.Lookup
// OT object->type Object.Type
// TT type->type Type.{Elem,Key,Params,Results,Underlying} [EKPRU]
// TO type->object Type.{At,Field,Method,Obj} [AFMO]
//
// All valid paths start with a package and end at an object
// and thus may be defined by the regular language:
//
// objectpath = PO (OT TT* TO)*
//
// The concrete encoding follows directly:
// - The only PO operator is Package.Scope.Lookup, which requires an identifier.
// - The only OT operator is Object.Type,
// which we encode as '.' because dot cannot appear in an identifier.
// - The TT operators are encoded as [EKPRU].
// - The OT operators are encoded as [AFMO];
// three of these (At,Field,Method) require an integer operand,
// which is encoded as a string of decimal digits.
// These indices are stable across different representations
// of the same package, even source and export data.
//
// In the example below,
//
// package p
//
// type T interface {
// f() (a string, b struct{ X int })
// }
//
// field X has the path "T.UM0.RA1.F0",
// representing the following sequence of operations:
//
// p.Lookup("T") T
// .Type().Underlying().Method(0). f
// .Type().Results().At(1) b
// .Type().Field(0) X
//
// The encoding is not maximally compact---every R or P is
// followed by an A, for example---but this simplifies the
// encoder and decoder.
//
const (
// object->type operators
opType = '.' // .Type() (Object)
// type->type operators
opElem = 'E' // .Elem() (Pointer, Slice, Array, Chan, Map)
opKey = 'K' // .Key() (Map)
opParams = 'P' // .Params() (Signature)
opResults = 'R' // .Results() (Signature)
opUnderlying = 'U' // .Underlying() (Named)
// type->object operators
opAt = 'A' // .At(i) (Tuple)
opField = 'F' // .Field(i) (Struct)
opMethod = 'M' // .Method(i) (Named or Interface; not Struct: "promoted" names are ignored)
opObj = 'O' // .Obj() (Named)
)
// The For function returns the path to an object relative to its package,
// or an error if the object is not accessible from the package's Scope.
//
// The For function guarantees to return a path only for the following objects:
// - package-level types
// - exported package-level non-types
// - methods
// - parameter and result variables
// - struct fields
// These objects are sufficient to define the API of their package.
// The objects described by a package's export data are drawn from this set.
//
// For does not return a path for predeclared names, imported package
// names, local names, and unexported package-level names (except
// types).
//
// Example: given this definition,
//
// package p
//
// type T interface {
// f() (a string, b struct{ X int })
// }
//
// For(X) would return a path that denotes the following sequence of operations:
//
// p.Scope().Lookup("T") (TypeName T)
// .Type().Underlying().Method(0). (method Func f)
// .Type().Results().At(1) (field Var b)
// .Type().Field(0) (field Var X)
//
// where p is the package (*types.Package) to which X belongs.
func For(obj types.Object) (Path, error) {
pkg := obj.Pkg()
// This table lists the cases of interest.
//
// Object Action
// ------ ------
// nil reject
// builtin reject
// pkgname reject
// label reject
// var
// package-level accept
// func param/result accept
// local reject
// struct field accept
// const
// package-level accept
// local reject
// func
// package-level accept
// init functions reject
// concrete method accept
// interface method accept
// type
// package-level accept
// local reject
//
// The only accessible package-level objects are members of pkg itself.
//
// The cases are handled in four steps:
//
// 1. reject nil and builtin
// 2. accept package-level objects
// 3. reject obviously invalid objects
// 4. search the API for the path to the param/result/field/method.
// 1. reference to nil or builtin?
if pkg == nil {
return "", fmt.Errorf("predeclared %s has no path", obj)
}
scope := pkg.Scope()
// 2. package-level object?
if scope.Lookup(obj.Name()) == obj {
// Only exported objects (and non-exported types) have a path.
// Non-exported types may be referenced by other objects.
if _, ok := obj.(*types.TypeName); !ok && !obj.Exported() {
return "", fmt.Errorf("no path for non-exported %v", obj)
}
return Path(obj.Name()), nil
}
// 3. Not a package-level object.
// Reject obviously non-viable cases.
switch obj := obj.(type) {
case *types.Const, // Only package-level constants have a path.
*types.TypeName, // Only package-level types have a path.
*types.Label, // Labels are function-local.
*types.PkgName: // PkgNames are file-local.
return "", fmt.Errorf("no path for %v", obj)
case *types.Var:
// Could be:
// - a field (obj.IsField())
// - a func parameter or result
// - a local var.
// Sadly there is no way to distinguish
// a param/result from a local
// so we must proceed to the find.
case *types.Func:
// A func, if not package-level, must be a method.
if recv := obj.Type().(*types.Signature).Recv(); recv == nil {
return "", fmt.Errorf("func is not a method: %v", obj)
}
// TODO(adonovan): opt: if the method is concrete,
// do a specialized version of the rest of this function so
// that it's O(1) not O(|scope|). Basically 'find' is needed
// only for struct fields and interface methods.
default:
panic(obj)
}
// 4. Search the API for the path to the var (field/param/result) or method.
// First inspect package-level named types.
// In the presence of path aliases, these give
// the best paths because non-types may
// refer to types, but not the reverse.
empty := make([]byte, 0, 48) // initial space
for _, name := range scope.Names() {
o := scope.Lookup(name)
tname, ok := o.(*types.TypeName)
if !ok {
continue // handle non-types in second pass
}
path := append(empty, name...)
path = append(path, opType)
T := o.Type()
if tname.IsAlias() {
// type alias
if r := find(obj, T, path); r != nil {
return Path(r), nil
}
} else {
// defined (named) type
if r := find(obj, T.Underlying(), append(path, opUnderlying)); r != nil {
return Path(r), nil
}
}
}
// Then inspect everything else:
// non-types, and declared methods of defined types.
for _, name := range scope.Names() {
o := scope.Lookup(name)
path := append(empty, name...)
if _, ok := o.(*types.TypeName); !ok {
if o.Exported() {
// exported non-type (const, var, func)
if r := find(obj, o.Type(), append(path, opType)); r != nil {
return Path(r), nil
}
}
continue
}
// Inspect declared methods of defined types.
if T, ok := o.Type().(*types.Named); ok {
path = append(path, opType)
for i := 0; i < T.NumMethods(); i++ {
m := T.Method(i)
path2 := appendOpArg(path, opMethod, i)
if m == obj {
return Path(path2), nil // found declared method
}
if r := find(obj, m.Type(), append(path2, opType)); r != nil {
return Path(r), nil
}
}
}
}
return "", fmt.Errorf("can't find path for %v in %s", obj, pkg.Path())
}
func appendOpArg(path []byte, op byte, arg int) []byte {
path = append(path, op)
path = strconv.AppendInt(path, int64(arg), 10)
return path
}
// find finds obj within type T, returning the path to it, or nil if not found.
func find(obj types.Object, T types.Type, path []byte) []byte {
switch T := T.(type) {
case *types.Basic, *types.Named:
// Named types belonging to pkg were handled already,
// so T must belong to another package. No path.
return nil
case *types.Pointer:
return find(obj, T.Elem(), append(path, opElem))
case *types.Slice:
return find(obj, T.Elem(), append(path, opElem))
case *types.Array:
return find(obj, T.Elem(), append(path, opElem))
case *types.Chan:
return find(obj, T.Elem(), append(path, opElem))
case *types.Map:
if r := find(obj, T.Key(), append(path, opKey)); r != nil {
return r
}
return find(obj, T.Elem(), append(path, opElem))
case *types.Signature:
if r := find(obj, T.Params(), append(path, opParams)); r != nil {
return r
}
return find(obj, T.Results(), append(path, opResults))
case *types.Struct:
for i := 0; i < T.NumFields(); i++ {
f := T.Field(i)
path2 := appendOpArg(path, opField, i)
if f == obj {
return path2 // found field var
}
if r := find(obj, f.Type(), append(path2, opType)); r != nil {
return r
}
}
return nil
case *types.Tuple:
for i := 0; i < T.Len(); i++ {
v := T.At(i)
path2 := appendOpArg(path, opAt, i)
if v == obj {
return path2 // found param/result var
}
if r := find(obj, v.Type(), append(path2, opType)); r != nil {
return r
}
}
return nil
case *types.Interface:
for i := 0; i < T.NumMethods(); i++ {
m := T.Method(i)
path2 := appendOpArg(path, opMethod, i)
if m == obj {
return path2 // found interface method
}
if r := find(obj, m.Type(), append(path2, opType)); r != nil {
return r
}
}
return nil
}
panic(T)
}
// Object returns the object denoted by path p within the package pkg.
func Object(pkg *types.Package, p Path) (types.Object, error) {
if p == "" {
return nil, fmt.Errorf("empty path")
}
pathstr := string(p)
var pkgobj, suffix string
if dot := strings.IndexByte(pathstr, opType); dot < 0 {
pkgobj = pathstr
} else {
pkgobj = pathstr[:dot]
suffix = pathstr[dot:] // suffix starts with "."
}
obj := pkg.Scope().Lookup(pkgobj)
if obj == nil {
return nil, fmt.Errorf("package %s does not contain %q", pkg.Path(), pkgobj)
}
// abtraction of *types.{Pointer,Slice,Array,Chan,Map}
type hasElem interface {
Elem() types.Type
}
// abstraction of *types.{Interface,Named}
type hasMethods interface {
Method(int) *types.Func
NumMethods() int
}
// The loop state is the pair (t, obj),
// exactly one of which is non-nil, initially obj.
// All suffixes start with '.' (the only object->type operation),
// followed by optional type->type operations,
// then a type->object operation.
// The cycle then repeats.
var t types.Type
for suffix != "" {
code := suffix[0]
suffix = suffix[1:]
// Codes [AFM] have an integer operand.
var index int
switch code {
case opAt, opField, opMethod:
rest := strings.TrimLeft(suffix, "0123456789")
numerals := suffix[:len(suffix)-len(rest)]
suffix = rest
i, err := strconv.Atoi(numerals)
if err != nil {
return nil, fmt.Errorf("invalid path: bad numeric operand %q for code %q", numerals, code)
}
index = int(i)
case opObj:
// no operand
default:
// The suffix must end with a type->object operation.
if suffix == "" {
return nil, fmt.Errorf("invalid path: ends with %q, want [AFMO]", code)
}
}
if code == opType {
if t != nil {
return nil, fmt.Errorf("invalid path: unexpected %q in type context", opType)
}
t = obj.Type()
obj = nil
continue
}
if t == nil {
return nil, fmt.Errorf("invalid path: code %q in object context", code)
}
// Inv: t != nil, obj == nil
switch code {
case opElem:
hasElem, ok := t.(hasElem) // Pointer, Slice, Array, Chan, Map
if !ok {
return nil, fmt.Errorf("cannot apply %q to %s (got %T, want pointer, slice, array, chan or map)", code, t, t)
}
t = hasElem.Elem()
case opKey:
mapType, ok := t.(*types.Map)
if !ok {
return nil, fmt.Errorf("cannot apply %q to %s (got %T, want map)", code, t, t)
}
t = mapType.Key()
case opParams:
sig, ok := t.(*types.Signature)
if !ok {
return nil, fmt.Errorf("cannot apply %q to %s (got %T, want signature)", code, t, t)
}
t = sig.Params()
case opResults:
sig, ok := t.(*types.Signature)
if !ok {
return nil, fmt.Errorf("cannot apply %q to %s (got %T, want signature)", code, t, t)
}
t = sig.Results()
case opUnderlying:
named, ok := t.(*types.Named)
if !ok {
return nil, fmt.Errorf("cannot apply %q to %s (got %s, want named)", code, t, t)
}
t = named.Underlying()
case opAt:
tuple, ok := t.(*types.Tuple)
if !ok {
return nil, fmt.Errorf("cannot apply %q to %s (got %s, want tuple)", code, t, t)
}
if n := tuple.Len(); index >= n {
return nil, fmt.Errorf("tuple index %d out of range [0-%d)", index, n)
}
obj = tuple.At(index)
t = nil
case opField:
structType, ok := t.(*types.Struct)
if !ok {
return nil, fmt.Errorf("cannot apply %q to %s (got %T, want struct)", code, t, t)
}
if n := structType.NumFields(); index >= n {
return nil, fmt.Errorf("field index %d out of range [0-%d)", index, n)
}
obj = structType.Field(index)
t = nil
case opMethod:
hasMethods, ok := t.(hasMethods) // Interface or Named
if !ok {
return nil, fmt.Errorf("cannot apply %q to %s (got %s, want interface or named)", code, t, t)
}
if n := hasMethods.NumMethods(); index >= n {
return nil, fmt.Errorf("method index %d out of range [0-%d)", index, n)
}
obj = hasMethods.Method(index)
t = nil
case opObj:
named, ok := t.(*types.Named)
if !ok {
return nil, fmt.Errorf("cannot apply %q to %s (got %s, want named)", code, t, t)
}
obj = named.Obj()
t = nil
default:
return nil, fmt.Errorf("invalid path: unknown code %q", code)
}
}
if obj.Pkg() != pkg {
return nil, fmt.Errorf("path denotes %s, which belongs to a different package", obj)
}
return obj, nil // success
}
src/cmd/vendor/golang.org/x/tools/go/types/typeutil/callee.go 0 → 100644
View file @ 8b469209
// Copyright 2018 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
package typeutil
import (
"go/ast"
"go/types"
"golang.org/x/tools/go/ast/astutil"
)
// Callee returns the named target of a function call, if any:
// a function, method, builtin, or variable.
func Callee(info *types.Info, call *ast.CallExpr) types.Object {
var obj types.Object
switch fun := astutil.Unparen(call.Fun).(type) {
case *ast.Ident:
obj = info.Uses[fun] // type, var, builtin, or declared func
case *ast.SelectorExpr:
if sel, ok := info.Selections[fun]; ok {
obj = sel.Obj() // method or field
} else {
obj = info.Uses[fun.Sel] // qualified identifier?
}
}
if _, ok := obj.(*types.TypeName); ok {
return nil // T(x) is a conversion, not a call
}
return obj
}
// StaticCallee returns the target (function or method) of a static
// function call, if any. It returns nil for calls to builtins.
func StaticCallee(info *types.Info, call *ast.CallExpr) *types.Func {
if f, ok := Callee(info, call).(*types.Func); ok && !interfaceMethod(f) {
return f
}
return nil
}
func interfaceMethod(f *types.Func) bool {
recv := f.Type().(*types.Signature).Recv()
return recv != nil && types.IsInterface(recv.Type())
}
src/cmd/vendor/golang.org/x/tools/go/types/typeutil/imports.go 0 → 100644
View file @ 8b469209
// Copyright 2014 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
package typeutil
import "go/types"
// Dependencies returns all dependencies of the specified packages.
//
// Dependent packages appear in topological order: if package P imports
// package Q, Q appears earlier than P in the result.
// The algorithm follows import statements in the order they
// appear in the source code, so the result is a total order.
//
func Dependencies(pkgs ...*types.Package) []*types.Package {
var result []*types.Package
seen := make(map[*types.Package]bool)
var visit func(pkgs []*types.Package)
visit = func(pkgs []*types.Package) {
for _, p := range pkgs {
if !seen[p] {
seen[p] = true
visit(p.Imports())
result = append(result, p)
}
}
}
visit(pkgs)
return result
}
src/cmd/vendor/golang.org/x/tools/go/types/typeutil/map.go 0 → 100644
View file @ 8b469209
// Copyright 2014 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
// Package typeutil defines various utilities for types, such as Map,
// a mapping from types.Type to interface{} values.
package typeutil // import "golang.org/x/tools/go/types/typeutil"
import (
"bytes"
"fmt"
"go/types"
"reflect"
)
// Map is a hash-table-based mapping from types (types.Type) to
// arbitrary interface{} values. The concrete types that implement
// the Type interface are pointers. Since they are not canonicalized,
// == cannot be used to check for equivalence, and thus we cannot
// simply use a Go map.
//
// Just as with map[K]V, a nil *Map is a valid empty map.
//
// Not thread-safe.
//
type Map struct {
hasher Hasher // shared by many Maps
table map[uint32][]entry // maps hash to bucket; entry.key==nil means unused
length int // number of map entries
}
// entry is an entry (key/value association) in a hash bucket.
type entry struct {
key types.Type
value interface{}
}
// SetHasher sets the hasher used by Map.
//
// All Hashers are functionally equivalent but contain internal state
// used to cache the results of hashing previously seen types.
//
// A single Hasher created by MakeHasher() may be shared among many
// Maps. This is recommended if the instances have many keys in
// common, as it will amortize the cost of hash computation.
//
// A Hasher may grow without bound as new types are seen. Even when a
// type is deleted from the map, the Hasher never shrinks, since other
// types in the map may reference the deleted type indirectly.
//
// Hashers are not thread-safe, and read-only operations such as
// Map.Lookup require updates to the hasher, so a full Mutex lock (not a
// read-lock) is require around all Map operations if a shared
// hasher is accessed from multiple threads.
//
// If SetHasher is not called, the Map will create a private hasher at
// the first call to Insert.
//
func (m *Map) SetHasher(hasher Hasher) {
m.hasher = hasher
}
// Delete removes the entry with the given key, if any.
// It returns true if the entry was found.
//
func (m *Map) Delete(key types.Type) bool {
if m != nil && m.table != nil {
hash := m.hasher.Hash(key)
bucket := m.table[hash]
for i, e := range bucket {
if e.key != nil && types.Identical(key, e.key) {
// We can't compact the bucket as it
// would disturb iterators.
bucket[i] = entry{}
m.length--
return true
}
}
}
return false
}
// At returns the map entry for the given key.
// The result is nil if the entry is not present.
//
func (m *Map) At(key types.Type) interface{} {
if m != nil && m.table != nil {
for _, e := range m.table[m.hasher.Hash(key)] {
if e.key != nil && types.Identical(key, e.key) {
return e.value
}
}
}
return nil
}
// Set sets the map entry for key to val,
// and returns the previous entry, if any.
func (m *Map) Set(key types.Type, value interface{}) (prev interface{}) {
if m.table != nil {
hash := m.hasher.Hash(key)
bucket := m.table[hash]
var hole *entry
for i, e := range bucket {
if e.key == nil {
hole = &bucket[i]
} else if types.Identical(key, e.key) {
prev = e.value
bucket[i].value = value
return
}
}
if hole != nil {
*hole = entry{key, value} // overwrite deleted entry
} else {
m.table[hash] = append(bucket, entry{key, value})
}
} else {
if m.hasher.memo == nil {
m.hasher = MakeHasher()
}
hash := m.hasher.Hash(key)
m.table = map[uint32][]entry{hash: {entry{key, value}}}
}
m.length++
return
}
// Len returns the number of map entries.
func (m *Map) Len() int {
if m != nil {
return m.length
}
return 0
}
// Iterate calls function f on each entry in the map in unspecified order.
//
// If f should mutate the map, Iterate provides the same guarantees as
// Go maps: if f deletes a map entry that Iterate has not yet reached,
// f will not be invoked for it, but if f inserts a map entry that
// Iterate has not yet reached, whether or not f will be invoked for
// it is unspecified.
//
func (m *Map) Iterate(f func(key types.Type, value interface{})) {
if m != nil {
for _, bucket := range m.table {
for _, e := range bucket {
if e.key != nil {
f(e.key, e.value)
}
}
}
}
}
// Keys returns a new slice containing the set of map keys.
// The order is unspecified.
func (m *Map) Keys() []types.Type {
keys := make([]types.Type, 0, m.Len())
m.Iterate(func(key types.Type, _ interface{}) {
keys = append(keys, key)
})
return keys
}
func (m *Map) toString(values bool) string {
if m == nil {
return "{}"
}
var buf bytes.Buffer
fmt.Fprint(&buf, "{")
sep := ""
m.Iterate(func(key types.Type, value interface{}) {
fmt.Fprint(&buf, sep)
sep = ", "
fmt.Fprint(&buf, key)
if values {
fmt.Fprintf(&buf, ": %q", value)
}
})
fmt.Fprint(&buf, "}")
return buf.String()
}
// String returns a string representation of the map's entries.
// Values are printed using fmt.Sprintf("%v", v).
// Order is unspecified.
//
func (m *Map) String() string {
return m.toString(true)
}
// KeysString returns a string representation of the map's key set.
// Order is unspecified.
//
func (m *Map) KeysString() string {
return m.toString(false)
}
////////////////////////////////////////////////////////////////////////
// Hasher
// A Hasher maps each type to its hash value.
// For efficiency, a hasher uses memoization; thus its memory
// footprint grows monotonically over time.
// Hashers are not thread-safe.
// Hashers have reference semantics.
// Call MakeHasher to create a Hasher.
type Hasher struct {
memo map[types.Type]uint32
}
// MakeHasher returns a new Hasher instance.
func MakeHasher() Hasher {
return Hasher{make(map[types.Type]uint32)}
}
// Hash computes a hash value for the given type t such that
// Identical(t, t') => Hash(t) == Hash(t').
func (h Hasher) Hash(t types.Type) uint32 {
hash, ok := h.memo[t]
if !ok {
hash = h.hashFor(t)
h.memo[t] = hash
}
return hash
}
// hashString computes the Fowler–Noll–Vo hash of s.
func hashString(s string) uint32 {
var h uint32
for i := 0; i < len(s); i++ {
h ^= uint32(s[i])
h *= 16777619
}
return h
}
// hashFor computes the hash of t.
func (h Hasher) hashFor(t types.Type) uint32 {
// See Identical for rationale.
switch t := t.(type) {
case *types.Basic:
return uint32(t.Kind())
case *types.Array:
return 9043 + 2*uint32(t.Len()) + 3*h.Hash(t.Elem())
case *types.Slice:
return 9049 + 2*h.Hash(t.Elem())
case *types.Struct:
var hash uint32 = 9059
for i, n := 0, t.NumFields(); i < n; i++ {
f := t.Field(i)
if f.Anonymous() {
hash += 8861
}
hash += hashString(t.Tag(i))
hash += hashString(f.Name()) // (ignore f.Pkg)
hash += h.Hash(f.Type())
}
return hash
case *types.Pointer:
return 9067 + 2*h.Hash(t.Elem())
case *types.Signature:
var hash uint32 = 9091
if t.Variadic() {
hash *= 8863
}
return hash + 3*h.hashTuple(t.Params()) + 5*h.hashTuple(t.Results())
case *types.Interface:
var hash uint32 = 9103
for i, n := 0, t.NumMethods(); i < n; i++ {
// See go/types.identicalMethods for rationale.
// Method order is not significant.
// Ignore m.Pkg().
m := t.Method(i)
hash += 3*hashString(m.Name()) + 5*h.Hash(m.Type())
}
return hash
case *types.Map:
return 9109 + 2*h.Hash(t.Key()) + 3*h.Hash(t.Elem())
case *types.Chan:
return 9127 + 2*uint32(t.Dir()) + 3*h.Hash(t.Elem())
case *types.Named:
// Not safe with a copying GC; objects may move.
return uint32(reflect.ValueOf(t.Obj()).Pointer())
case *types.Tuple:
return h.hashTuple(t)
}
panic(t)
}
func (h Hasher) hashTuple(tuple *types.Tuple) uint32 {
// See go/types.identicalTypes for rationale.
n := tuple.Len()
var hash uint32 = 9137 + 2*uint32(n)
for i := 0; i < n; i++ {
hash += 3 * h.Hash(tuple.At(i).Type())
}
return hash
}
src/cmd/vendor/golang.org/x/tools/go/types/typeutil/methodsetcache.go 0 → 100644
View file @ 8b469209
// Copyright 2014 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
// This file implements a cache of method sets.
package typeutil
import (
"go/types"
"sync"
)
// A MethodSetCache records the method set of each type T for which
// MethodSet(T) is called so that repeat queries are fast.
// The zero value is a ready-to-use cache instance.
type MethodSetCache struct {
mu sync.Mutex
named map[*types.Named]struct{ value, pointer *types.MethodSet } // method sets for named N and *N
others map[types.Type]*types.MethodSet // all other types
}
// MethodSet returns the method set of type T. It is thread-safe.
//
// If cache is nil, this function is equivalent to types.NewMethodSet(T).
// Utility functions can thus expose an optional *MethodSetCache
// parameter to clients that care about performance.
//
func (cache *MethodSetCache) MethodSet(T types.Type) *types.MethodSet {
if cache == nil {
return types.NewMethodSet(T)
}
cache.mu.Lock()
defer cache.mu.Unlock()
switch T := T.(type) {
case *types.Named:
return cache.lookupNamed(T).value
case *types.Pointer:
if N, ok := T.Elem().(*types.Named); ok {
return cache.lookupNamed(N).pointer
}
}
// all other types
// (The map uses pointer equivalence, not type identity.)
mset := cache.others[T]
if mset == nil {
mset = types.NewMethodSet(T)
if cache.others == nil {
cache.others = make(map[types.Type]*types.MethodSet)
}
cache.others[T] = mset
}
return mset
}
func (cache *MethodSetCache) lookupNamed(named *types.Named) struct{ value, pointer *types.MethodSet } {
if cache.named == nil {
cache.named = make(map[*types.Named]struct{ value, pointer *types.MethodSet })
}
// Avoid recomputing mset(*T) for each distinct Pointer
// instance whose underlying type is a named type.
msets, ok := cache.named[named]
if !ok {
msets.value = types.NewMethodSet(named)
msets.pointer = types.NewMethodSet(types.NewPointer(named))
cache.named[named] = msets
}
return msets
}
src/cmd/vendor/golang.org/x/tools/go/types/typeutil/ui.go 0 → 100644
View file @ 8b469209
// Copyright 2014 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
package typeutil
// This file defines utilities for user interfaces that display types.
import "go/types"
// IntuitiveMethodSet returns the intuitive method set of a type T,
// which is the set of methods you can call on an addressable value of
// that type.
//
// The result always contains MethodSet(T), and is exactly MethodSet(T)
// for interface types and for pointer-to-concrete types.
// For all other concrete types T, the result additionally
// contains each method belonging to *T if there is no identically
// named method on T itself.
//
// This corresponds to user intuition about method sets;
// this function is intended only for user interfaces.
//
// The order of the result is as for types.MethodSet(T).
//
func IntuitiveMethodSet(T types.Type, msets *MethodSetCache) []*types.Selection {
isPointerToConcrete := func(T types.Type) bool {
ptr, ok := T.(*types.Pointer)
return ok && !types.IsInterface(ptr.Elem())
}
var result []*types.Selection
mset := msets.MethodSet(T)
if types.IsInterface(T) || isPointerToConcrete(T) {
for i, n := 0, mset.Len(); i < n; i++ {
result = append(result, mset.At(i))
}
} else {
// T is some other concrete type.
// Report methods of T and *T, preferring those of T.
pmset := msets.MethodSet(types.NewPointer(T))
for i, n := 0, pmset.Len(); i < n; i++ {
meth := pmset.At(i)
if m := mset.Lookup(meth.Obj().Pkg(), meth.Obj().Name()); m != nil {
meth = m
}
result = append(result, meth)
}
}
return result
}
src/cmd/vendor/vendor.json
View file @ 8b469209
...@@ -165,6 +165,210 @@ ...@@ -165,6 +165,210 @@
"path": "golang.org/x/sys/windows/svc/mgr", "path": "golang.org/x/sys/windows/svc/mgr",
"revision": "90868a75fefd03942536221d7c0e2f84ec62a668", "revision": "90868a75fefd03942536221d7c0e2f84ec62a668",
"revisionTime": "2018-08-01T20:46:00Z" "revisionTime": "2018-08-01T20:46:00Z"
},
{
"checksumSHA1": "witNkDO7koGO7+oxpBMZBvoxz3c=",
"path": "golang.org/x/tools/go/analysis",
"revision": "c76e1ad98a635a7c069d7ab43d31fcf38381facc",
"revisionTime": "2018-11-05T19:48:08Z"
},
{
"checksumSHA1": "NPcubwbqmr2yGfGztLqizwbXrwM=",
"path": "golang.org/x/tools/go/analysis/cmd/vet-lite",
"revision": "c76e1ad98a635a7c069d7ab43d31fcf38381facc",
"revisionTime": "2018-11-05T19:48:08Z"
},
{
"checksumSHA1": "kWG+JiD2mA+2pnSeYJrKLHHgT+s=",
"path": "golang.org/x/tools/go/analysis/internal/analysisflags",
"revision": "c76e1ad98a635a7c069d7ab43d31fcf38381facc",
"revisionTime": "2018-11-05T19:48:08Z"
},
{
"checksumSHA1": "c4FY3+yRC2GHON66hIU254nQxA8=",
"path": "golang.org/x/tools/go/analysis/internal/facts",
"revision": "c76e1ad98a635a7c069d7ab43d31fcf38381facc",
"revisionTime": "2018-11-05T19:48:08Z"
},
{
"checksumSHA1": "Zuz7FbEMWtUNCKTA+ofVkkDl1Ic=",
"path": "golang.org/x/tools/go/analysis/internal/unitchecker",
"revision": "c76e1ad98a635a7c069d7ab43d31fcf38381facc",
"revisionTime": "2018-11-05T19:48:08Z"
},
{
"checksumSHA1": "fxi2KL0typcqGp87Qa9CxSp89Sk=",
"path": "golang.org/x/tools/go/analysis/passes/asmdecl",
"revision": "c76e1ad98a635a7c069d7ab43d31fcf38381facc",
"revisionTime": "2018-11-05T19:48:08Z"
},
{
"checksumSHA1": "AK5vKjJmQD1u/6v/s107upAF03w=",
"path": "golang.org/x/tools/go/analysis/passes/assign",
"revision": "c76e1ad98a635a7c069d7ab43d31fcf38381facc",
"revisionTime": "2018-11-05T19:48:08Z"
},
{
"checksumSHA1": "qRQNlOhRmTPecqsjJMf3Rxd7M1g=",
"path": "golang.org/x/tools/go/analysis/passes/atomic",
"revision": "c76e1ad98a635a7c069d7ab43d31fcf38381facc",
"revisionTime": "2018-11-05T19:48:08Z"
},
{
"checksumSHA1": "zhnbma06ExmGYTu5QaGAi5+QciY=",
"path": "golang.org/x/tools/go/analysis/passes/bools",
"revision": "c76e1ad98a635a7c069d7ab43d31fcf38381facc",
"revisionTime": "2018-11-05T19:48:08Z"
},
{
"checksumSHA1": "HWcvlzqG20E9BaG4/j3u9tnUyZ4=",
"path": "golang.org/x/tools/go/analysis/passes/buildtag",
"revision": "c76e1ad98a635a7c069d7ab43d31fcf38381facc",
"revisionTime": "2018-11-05T19:48:08Z"
},
{
"checksumSHA1": "ekVwfAw224CT/eBihMCzAOzIHiE=",
"path": "golang.org/x/tools/go/analysis/passes/cgocall",
"revision": "c76e1ad98a635a7c069d7ab43d31fcf38381facc",
"revisionTime": "2018-11-05T19:48:08Z"
},
{
"checksumSHA1": "dwtQdPi0Jb9BYVr0Gynh5NpCSz8=",
"path": "golang.org/x/tools/go/analysis/passes/composite",
"revision": "c76e1ad98a635a7c069d7ab43d31fcf38381facc",
"revisionTime": "2018-11-05T19:48:08Z"
},
{
"checksumSHA1": "6M8xb//gcLk3dSpRq6/fb/8Wvqk=",
"path": "golang.org/x/tools/go/analysis/passes/copylock",
"revision": "c76e1ad98a635a7c069d7ab43d31fcf38381facc",
"revisionTime": "2018-11-05T19:48:08Z"
},
{
"checksumSHA1": "DPQnIktTEV7cNBNDRIpg0OK6v9Q=",
"path": "golang.org/x/tools/go/analysis/passes/ctrlflow",
"revision": "c76e1ad98a635a7c069d7ab43d31fcf38381facc",
"revisionTime": "2018-11-05T19:48:08Z"
},
{
"checksumSHA1": "GJjZZhXYqMoGmym/2DpExqHP+Cw=",
"path": "golang.org/x/tools/go/analysis/passes/httpresponse",
"revision": "c76e1ad98a635a7c069d7ab43d31fcf38381facc",
"revisionTime": "2018-11-05T19:48:08Z"
},
{
"checksumSHA1": "Q76YV1xYtBCBsZk7uKXqih7iHL4=",
"path": "golang.org/x/tools/go/analysis/passes/inspect",
"revision": "c76e1ad98a635a7c069d7ab43d31fcf38381facc",
"revisionTime": "2018-11-05T19:48:08Z"
},
{
"checksumSHA1": "Y7NBmaqiGnVWf3yn16cwbWmgUhI=",
"path": "golang.org/x/tools/go/analysis/passes/internal/analysisutil",
"revision": "c76e1ad98a635a7c069d7ab43d31fcf38381facc",
"revisionTime": "2018-11-05T19:48:08Z"
},
{
"checksumSHA1": "Fjj6sV+qmJwvxGt/i8fLIma9Lzs=",
"path": "golang.org/x/tools/go/analysis/passes/loopclosure",
"revision": "c76e1ad98a635a7c069d7ab43d31fcf38381facc",
"revisionTime": "2018-11-05T19:48:08Z"
},
{
"checksumSHA1": "VZE2qx/m2esvfEreS0RCaVoWYhc=",
"path": "golang.org/x/tools/go/analysis/passes/lostcancel",
"revision": "c76e1ad98a635a7c069d7ab43d31fcf38381facc",
"revisionTime": "2018-11-05T19:48:08Z"
},
{
"checksumSHA1": "xf9nMwSbFWJXDC9W+Gnus+uU0Nw=",
"path": "golang.org/x/tools/go/analysis/passes/nilfunc",
"revision": "c76e1ad98a635a7c069d7ab43d31fcf38381facc",
"revisionTime": "2018-11-05T19:48:08Z"
},
{
"checksumSHA1": "PKByrfYKilYhkhAE01z5Om0Tr+w=",
"path": "golang.org/x/tools/go/analysis/passes/pkgfact",
"revision": "c76e1ad98a635a7c069d7ab43d31fcf38381facc",
"revisionTime": "2018-11-05T19:48:08Z"
},
{
"checksumSHA1": "BrlVsK8u6SPMyvoWdkwS4IAXVRI=",
"path": "golang.org/x/tools/go/analysis/passes/printf",
"revision": "c76e1ad98a635a7c069d7ab43d31fcf38381facc",
"revisionTime": "2018-11-05T19:48:08Z"
},
{
"checksumSHA1": "3w9Q99Mxrf8qEU+FH7lSyy5hwc4=",
"path": "golang.org/x/tools/go/analysis/passes/shift",
"revision": "c76e1ad98a635a7c069d7ab43d31fcf38381facc",
"revisionTime": "2018-11-05T19:48:08Z"
},
{
"checksumSHA1": "oeR6BB6OmfoYReHyNLEX9BbF1cI=",
"path": "golang.org/x/tools/go/analysis/passes/stdmethods",
"revision": "c76e1ad98a635a7c069d7ab43d31fcf38381facc",
"revisionTime": "2018-11-05T19:48:08Z"
},
{
"checksumSHA1": "rPSH7/W3vsomdmSIgdEDrzaCQyk=",
"path": "golang.org/x/tools/go/analysis/passes/structtag",
"revision": "c76e1ad98a635a7c069d7ab43d31fcf38381facc",
"revisionTime": "2018-11-05T19:48:08Z"
},
{
"checksumSHA1": "yHrglPUc3Ia12nwO0l/I0ArT3to=",
"path": "golang.org/x/tools/go/analysis/passes/tests",
"revision": "c76e1ad98a635a7c069d7ab43d31fcf38381facc",
"revisionTime": "2018-11-05T19:48:08Z"
},
{
"checksumSHA1": "en0VsP2OoNX40F/bNfbO6geSgi4=",
"path": "golang.org/x/tools/go/analysis/passes/unreachable",
"revision": "c76e1ad98a635a7c069d7ab43d31fcf38381facc",
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{
"checksumSHA1": "641akvyeQUx5MqoHiyKwRps4vEg=",
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},
{
"checksumSHA1": "cm27h0jINv4jlgiHMn7q572FXTY=",
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"revisionTime": "2018-11-05T19:48:08Z"
},
{
"checksumSHA1": "/bQnex6L/nyDuZCIIRbM6Is/IRY=",
"path": "golang.org/x/tools/go/ast/astutil",
"revision": "c76e1ad98a635a7c069d7ab43d31fcf38381facc",
"revisionTime": "2018-11-05T19:48:08Z"
},
{
"checksumSHA1": "qnZLWirp4hAxafiKvH+nnmgGf8Q=",
"path": "golang.org/x/tools/go/ast/inspector",
"revision": "c76e1ad98a635a7c069d7ab43d31fcf38381facc",
"revisionTime": "2018-11-05T19:48:08Z"
},
{
"checksumSHA1": "+g97ZSLGNNbqfBzpYje8fA5PvXs=",
"path": "golang.org/x/tools/go/cfg",
"revision": "c76e1ad98a635a7c069d7ab43d31fcf38381facc",
"revisionTime": "2018-11-05T19:48:08Z"
},
{
"checksumSHA1": "JWIR0GVqbDYhTW9mh4zpY/ve6Ro=",
"path": "golang.org/x/tools/go/types/objectpath",
"revision": "c76e1ad98a635a7c069d7ab43d31fcf38381facc",
"revisionTime": "2018-11-05T19:48:08Z"
},
{
"checksumSHA1": "kyVWOWK3PkDKCtXRJffE60MrfOo=",
"path": "golang.org/x/tools/go/types/typeutil",
"revision": "c76e1ad98a635a7c069d7ab43d31fcf38381facc",
"revisionTime": "2018-11-05T19:48:08Z"
} }
], ],
"rootPath": "/cmd" "rootPath": "/cmd"
......
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