document gotest

R=rsc
CC=go-dev
http://go/go-review/1017026

src/cmd/gotest/doc.go

+// Copyright 2009 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 gotest program is an automated testing tool for Go packages.
+
+Normally a Go package is compiled without its test files.  Gotest
+is a simple script that recompiles the package along with any files
+named *_test.go.  Functions in the test sources named TestXXX
+(where XXX is any alphanumeric string starting with an upper case
+letter) will be run when the binary is executed.  Gotest requires
+that the package have a standard package Makefile, one that
+includes go/src/Make.pkg.
+
+The test functions are run in the order they appear in the source.
+They should have signature
+
+	func TestXXX(t *testing.T) { ... }
+
+See the documentation of the testing package for more information.
+
+By default, gotest needs no arguments.  It compiles all the .go files
+in the directory, including tests, and runs the tests.  If file names
+are given, only those test files are added to the package.
+(The non-test files are always compiled.)
+
+The package is built in a special subdirectory so it does not
+interfere with the non-test installation.
+
+Usage:
+	gotest [pkg_test.go ...]
+
+The resulting binary, called (for amd64) 6.out, has a couple of
+arguments.
+
+Usage:
+	6.out [-v] [-match pattern]
+
+The -v flag causes the tests to be logged as they run.  The --match
+flag causes only those tests whose names match the regular expression
+pattern to be run. By default all tests are run silently.  If all
+the specified test pass, 6.out prints PASS and exits with a 0 exit
+code.  If any tests fail, it prints FAIL and exits with a non-zero
+code.
+
+*/
+package documentation