encoding/xml: bring API closer to other packages

Includes gofix module. The only case not covered should be
xml.Unmarshal, since it remains with a similar interface, and
would require introspecting the type of its first argument
better.

Fixes #2626.

R=golang-dev, rsc, gustavo
CC=golang-dev
https://golang.org/cl/5574053

misc/dashboard/builder/main.go

@@ -587,7 +587,7 @@ func commitPoll(key, pkg string) {
 	var logStruct struct {
 		Log []HgLog
 	}
-	err = xml.Unmarshal(strings.NewReader("<Top>"+data+"</Top>"), &logStruct)
+	err = xml.Unmarshal([]byte("<Top>"+data+"</Top>"), &logStruct)
 	if err != nil {
 		log.Printf("unmarshal hg log: %v", err)
 		return

src/cmd/godoc/codewalk.go

@@ -115,9 +115,9 @@ func loadCodewalk(filename string) (*Codewalk, error) {
 	}
 	defer f.Close()
 	cw := new(Codewalk)
-	p := xml.NewParser(f)
-	p.Entity = xml.HTMLEntity
-	err = p.Unmarshal(cw, nil)
+	d := xml.NewDecoder(f)
+	d.Entity = xml.HTMLEntity
+	err = d.Decode(cw)
 	if err != nil {
 		return nil, &os.PathError{"parsing", filename, err}
 	}

src/cmd/gofix/Makefile

@@ -42,6 +42,7 @@ GOFILES=\
 	timefileinfo.go\
 	typecheck.go\
 	url.go\
+	xmlapi.go\
 
 include ../../Make.cmd
 

src/cmd/gofix/xmlapi.go

+// 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 main
+
+import (
+	"go/ast"
+)
+
+func init() {
+	register(xmlapiFix)
+}
+
+var xmlapiFix = fix{
+	"xmlapi",
+	"2012-01-23",
+	xmlapi,
+	`
+	Make encoding/xml's API look more like the rest of the encoding packages.
+
+http://codereview.appspot.com/5574053
+`,
+}
+
+var xmlapiTypeConfig = &TypeConfig{
+	Func: map[string]string{
+		"xml.NewParser": "xml.Parser",
+	},
+}
+
+func xmlapi(f *ast.File) bool {
+	if !imports(f, "encoding/xml") {
+		return false
+	}
+
+	typeof, _ := typecheck(xmlapiTypeConfig, f)
+
+	fixed := false
+	walk(f, func(n interface{}) {
+		s, ok := n.(*ast.SelectorExpr)
+		if ok && typeof[s.X] == "xml.Parser" && s.Sel.Name == "Unmarshal" {
+			s.Sel.Name = "DecodeElement"
+			fixed = true
+			return
+		}
+		if ok && isPkgDot(s, "xml", "Parser") {
+			s.Sel.Name = "Decoder"
+			fixed = true
+			return
+		}
+
+		call, ok := n.(*ast.CallExpr)
+		if !ok {
+			return
+		}
+		switch {
+		case len(call.Args) == 2 && isPkgDot(call.Fun, "xml", "Marshal"):
+			*call = xmlMarshal(call.Args)
+			fixed = true
+		// Can't fix without further diving into the type of call.Args[0].
+		//case len(call.Args) == 2 && isPkgDot(call.Fun, "xml", "Unmarshal"):
+		//	*call = xmlUnmarshal(call.Args)
+		//	fixed = true
+		case len(call.Args) == 1 && isPkgDot(call.Fun, "xml", "NewParser"):
+			sel := call.Fun.(*ast.SelectorExpr).Sel
+			sel.Name = "NewDecoder"
+			fixed = true
+		}
+	})
+	return fixed
+}
+
+func xmlMarshal(args []ast.Expr) ast.CallExpr {
+	return xmlCallChain("NewEncoder", "Encode", args)
+}
+
+func xmlUnmarshal(args []ast.Expr) ast.CallExpr {
+	return xmlCallChain("NewDecoder", "Decode", args)
+}
+
+func xmlCallChain(first, second string, args []ast.Expr) ast.CallExpr {
+	return ast.CallExpr{
+		Fun: &ast.SelectorExpr{
+			X: &ast.CallExpr{
+				Fun: &ast.SelectorExpr{
+					X:   ast.NewIdent("xml"),
+					Sel: ast.NewIdent(first),
+				},
+				Args: args[:1],
+			},
+			Sel: ast.NewIdent(second),
+		},
+		Args: args[1:2],
+	}
+}

src/cmd/gofix/xmlapi_test.go

+// 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 main
+
+func init() {
+	addTestCases(xmlapiTests, xmlapi)
+}
+
+var xmlapiTests = []testCase{
+	{
+		Name: "xmlapi.0",
+		In: `package main
+
+import "encoding/xml"
+
+func f() {
+	xml.Marshal(a, b)
+	xml.Unmarshal(a, b)
+
+	p1 := xml.NewParser(stream)
+	p1.Unmarshal(v, start)
+
+	var p2 xml.Parser
+	p2.Unmarshal(v, start)
+}
+`,
+		Out: `package main
+
+import "encoding/xml"
+
+func f() {
+	xml.NewEncoder(a).Encode(b)
+	xml.Unmarshal(a, b)
+
+	p1 := xml.NewDecoder(stream)
+	p1.DecodeElement(v, start)
+
+	var p2 xml.Decoder
+	p2.DecodeElement(v, start)
+}
+`,
+	},
+}

src/pkg/encoding/xml/marshal.go

@@ -26,11 +26,7 @@ type Marshaler interface {
 	MarshalXML() ([]byte, error)
 }
 
-type printer struct {
-	*bufio.Writer
-}
-
-// Marshal writes an XML-formatted representation of v to w.
+// Marshal returns the XML encoding of v.
 //
 // If v implements Marshaler, then Marshal calls its MarshalXML method.
 // Otherwise, Marshal uses the following procedure to create the XML.
@@ -76,7 +72,7 @@ type printer struct {
 //		Age       int      `xml:"person>age"`
 //	}
 //
-//	xml.Marshal(w, &Result{Id: 13, FirstName: "John", LastName: "Doe", Age: 42})
+//	xml.Marshal(&Result{Id: 13, FirstName: "John", LastName: "Doe", Age: 42})
 //
 // would be marshalled as:
 //
@@ -91,13 +87,38 @@ type printer struct {
 //	</result>
 //
 // Marshal will return an error if asked to marshal a channel, function, or map.
-func Marshal(w io.Writer, v interface{}) (err error) {
-	p := &printer{bufio.NewWriter(w)}
-	err = p.marshalValue(reflect.ValueOf(v), nil)
-	p.Flush()
+func Marshal(v interface{}) ([]byte, error) {
+	var b bytes.Buffer
+	if err := NewEncoder(&b).Encode(v); err != nil {
+		return nil, err
+	}
+	return b.Bytes(), nil
+}
+
+// An Encoder writes XML data to an output stream.
+type Encoder struct {
+	printer
+}
+
+// NewEncoder returns a new encoder that writes to w.
+func NewEncoder(w io.Writer) *Encoder {
+	return &Encoder{printer{bufio.NewWriter(w)}}
+}
+
+// Encode writes the XML encoding of v to the stream.
+//
+// See the documentation for Marshal for details about the conversion
+// of Go values to XML.
+func (enc *Encoder) Encode(v interface{}) error {
+	err := enc.marshalValue(reflect.ValueOf(v), nil)
+	enc.Flush()
 	return err
 }
 
+type printer struct {
+	*bufio.Writer
+}
+
 func (p *printer) marshalValue(val reflect.Value, finfo *fieldInfo) error {
 	if !val.IsValid() {
 		return nil

src/pkg/encoding/xml/marshal_test.go

@@ -5,7 +5,6 @@
 package xml
 
 import (
-	"bytes"
 	"reflect"
 	"strconv"
 	"strings"
@@ -619,13 +618,12 @@ func TestMarshal(t *testing.T) {
 		if test.UnmarshalOnly {
 			continue
 		}
-		buf := bytes.NewBuffer(nil)
-		err := Marshal(buf, test.Value)
+		data, err := Marshal(test.Value)
 		if err != nil {
 			t.Errorf("#%d: Error: %s", idx, err)
 			continue
 		}
-		if got, want := buf.String(), test.ExpectXML; got != want {
+		if got, want := string(data), test.ExpectXML; got != want {
 			if strings.Contains(want, "\n") {
 				t.Errorf("#%d: marshal(%#v):\nHAVE:\n%s\nWANT:\n%s", idx, test.Value, got, want)
 			} else {
@@ -666,8 +664,7 @@ var marshalErrorTests = []struct {
 
 func TestMarshalErrors(t *testing.T) {
 	for idx, test := range marshalErrorTests {
-		buf := bytes.NewBuffer(nil)
-		err := Marshal(buf, test.Value)
+		_, err := Marshal(test.Value)
 		if err == nil || err.Error() != test.Err {
 			t.Errorf("#%d: marshal(%#v) = [error] %v, want %v", idx, test.Value, err, test.Err)
 		}
@@ -691,8 +688,7 @@ func TestUnmarshal(t *testing.T) {
 
 		vt := reflect.TypeOf(test.Value)
 		dest := reflect.New(vt.Elem()).Interface()
-		buffer := bytes.NewBufferString(test.ExpectXML)
-		err := Unmarshal(buffer, dest)
+		err := Unmarshal([]byte(test.ExpectXML), dest)
 
 		switch fix := dest.(type) {
 		case *Feed:
@@ -711,17 +707,14 @@ func TestUnmarshal(t *testing.T) {
 }
 
 func BenchmarkMarshal(b *testing.B) {
-	buf := bytes.NewBuffer(nil)
 	for i := 0; i < b.N; i++ {
-		Marshal(buf, atomValue)
-		buf.Truncate(0)
+		Marshal(atomValue)
 	}
 }
 
 func BenchmarkUnmarshal(b *testing.B) {
 	xml := []byte(atomXml)
 	for i := 0; i < b.N; i++ {
-		buffer := bytes.NewBuffer(xml)
-		Unmarshal(buffer, &Feed{})
+		Unmarshal(xml, &Feed{})
 	}
 }

src/pkg/encoding/xml/read.go

@@ -7,7 +7,6 @@ package xml
 import (
 	"bytes"
 	"errors"
-	"io"
 	"reflect"
 	"strconv"
 	"strings"
@@ -20,10 +19,10 @@ import (
 // See package json for a textual representation more suitable
 // to data structures.
 
-// Unmarshal parses an XML element from r and uses the
-// reflect library to fill in an arbitrary struct, slice, or string
-// pointed at by val.  Well-formed data that does not fit
-// into val is discarded.
+// Unmarshal parses the XML-encoded data and stores the result in
+// the value pointed to by v, which must be an arbitrary struct,
+// slice, or string. Well-formed data that does not fit into v is
+// discarded.
 //
 // For example, given these definitions:
 //
@@ -59,7 +58,7 @@ import (
 //		<address>123 Main Street</address>
 //	</result>
 //
-// via Unmarshal(r, &result) is equivalent to assigning
+// via Unmarshal(data, &result) is equivalent to assigning
 //
 //	r = Result{
 //		xml.Name{Local: "result"},
@@ -157,18 +156,26 @@ import (
 // Unmarshal maps an XML element to a pointer by setting the pointer
 // to a freshly allocated value and then mapping the element to that value.
 //
-func Unmarshal(r io.Reader, val interface{}) error {
-	v := reflect.ValueOf(val)
-	if v.Kind() != reflect.Ptr {
+func Unmarshal(data []byte, v interface{}) error {
+	return NewDecoder(bytes.NewBuffer(data)).Decode(v)
+}
+
+// Decode works like xml.Unmarshal, except it reads the decoder
+// stream to find the start element.
+func (d *Decoder) Decode(v interface{}) error {
+	return d.DecodeElement(v, nil)
+}
+
+// DecodeElement works like xml.Unmarshal except that it takes
+// a pointer to the start XML element to decode into v.
+// It is useful when a client reads some raw XML tokens itself
+// but also wants to defer to Unmarshal for some elements.
+func (d *Decoder) DecodeElement(v interface{}, start *StartElement) error {
+	val := reflect.ValueOf(v)
+	if val.Kind() != reflect.Ptr {
 		return errors.New("non-pointer passed to Unmarshal")
 	}
-	p := NewParser(r)
-	elem := v.Elem()
-	err := p.unmarshal(elem, nil)
-	if err != nil {
-		return err
-	}
-	return nil
+	return d.unmarshal(val.Elem(), start)
 }
 
 // An UnmarshalError represents an error in the unmarshalling process.
@@ -176,22 +183,8 @@ type UnmarshalError string
 
 func (e UnmarshalError) Error() string { return string(e) }
 
-// The Parser's Unmarshal method is like xml.Unmarshal
-// except that it can be passed a pointer to the initial start element,
-// useful when a client reads some raw XML tokens itself
-// but also defers to Unmarshal for some elements.
-// Passing a nil start element indicates that Unmarshal should
-// read the token stream to find the start element.
-func (p *Parser) Unmarshal(val interface{}, start *StartElement) error {
-	v := reflect.ValueOf(val)
-	if v.Kind() != reflect.Ptr {
-		return errors.New("non-pointer passed to Unmarshal")
-	}
-	return p.unmarshal(v.Elem(), start)
-}
-
 // Unmarshal a single XML element into val.
-func (p *Parser) unmarshal(val reflect.Value, start *StartElement) error {
+func (p *Decoder) unmarshal(val reflect.Value, start *StartElement) error {
 	// Find start element if we need it.
 	if start == nil {
 		for {
@@ -484,9 +477,9 @@ func copyValue(dst reflect.Value, src []byte) (err error) {
 // unmarshalPath walks down an XML structure looking for wanted
 // paths, and calls unmarshal on them.
 // The consumed result tells whether XML elements have been consumed
-// from the Parser until start's matching end element, or if it's
+// from the Decoder until start's matching end element, or if it's
 // still untouched because start is uninteresting for sv's fields.
-func (p *Parser) unmarshalPath(tinfo *typeInfo, sv reflect.Value, parents []string, start *StartElement) (consumed bool, err error) {
+func (p *Decoder) unmarshalPath(tinfo *typeInfo, sv reflect.Value, parents []string, start *StartElement) (consumed bool, err error) {
 	recurse := false
 Loop:
 	for i := range tinfo.fields {
@@ -550,7 +543,7 @@ Loop:
 // Read tokens until we find the end element.
 // Token is taking care of making sure the
 // end element matches the start element we saw.
-func (p *Parser) Skip() error {
+func (p *Decoder) Skip() error {
 	for {
 		tok, err := p.Token()
 		if err != nil {

src/pkg/encoding/xml/read_test.go

@@ -6,7 +6,6 @@ package xml
 
 import (
 	"reflect"
-	"strings"
 	"testing"
 )
 
@@ -14,7 +13,7 @@ import (
 
 func TestUnmarshalFeed(t *testing.T) {
 	var f Feed
-	if err := Unmarshal(strings.NewReader(atomFeedString), &f); err != nil {
+	if err := Unmarshal([]byte(atomFeedString), &f); err != nil {
 		t.Fatalf("Unmarshal: %s", err)
 	}
 	if !reflect.DeepEqual(f, atomFeed) {
@@ -281,7 +280,7 @@ var pathTests = []interface{}{
 func TestUnmarshalPaths(t *testing.T) {
 	for _, pt := range pathTests {
 		v := reflect.New(reflect.TypeOf(pt).Elem()).Interface()
-		if err := Unmarshal(strings.NewReader(pathTestString), v); err != nil {
+		if err := Unmarshal([]byte(pathTestString), v); err != nil {
 			t.Fatalf("Unmarshal: %s", err)
 		}
 		if !reflect.DeepEqual(v, pt) {
@@ -331,7 +330,7 @@ var badPathTests = []struct {
 
 func TestUnmarshalBadPaths(t *testing.T) {
 	for _, tt := range badPathTests {
-		err := Unmarshal(strings.NewReader(pathTestString), tt.v)
+		err := Unmarshal([]byte(pathTestString), tt.v)
 		if !reflect.DeepEqual(err, tt.e) {
 			t.Fatalf("Unmarshal with %#v didn't fail properly:\nhave %#v,\nwant %#v", tt.v, err, tt.e)
 		}
@@ -350,7 +349,7 @@ type TestThree struct {
 
 func TestUnmarshalWithoutNameType(t *testing.T) {
 	var x TestThree
-	if err := Unmarshal(strings.NewReader(withoutNameTypeData), &x); err != nil {
+	if err := Unmarshal([]byte(withoutNameTypeData), &x); err != nil {
 		t.Fatalf("Unmarshal: %s", err)
 	}
 	if x.Attr != OK {

src/pkg/encoding/xml/xml.go

@@ -36,7 +36,7 @@ func (e *SyntaxError) Error() string {
 
 // A Name represents an XML name (Local) annotated
 // with a name space identifier (Space).
-// In tokens returned by Parser.Token, the Space identifier
+// In tokens returned by Decoder.Token, the Space identifier
 // is given as a canonical URL, not the short prefix used
 // in the document being parsed.
 type Name struct {
@@ -124,9 +124,9 @@ func CopyToken(t Token) Token {
 	return t
 }
 
-// A Parser represents an XML parser reading a particular input stream.
+// A Decoder represents an XML parser reading a particular input stream.
 // The parser assumes that its input is encoded in UTF-8.
-type Parser struct {
+type Decoder struct {
 	// Strict defaults to true, enforcing the requirements
 	// of the XML specification.
 	// If set to false, the parser allows input containing common
@@ -139,9 +139,9 @@ type Parser struct {
 	//
 	// Setting:
 	//
-	//	p.Strict = false;
-	//	p.AutoClose = HTMLAutoClose;
-	//	p.Entity = HTMLEntity
+	//	d.Strict = false;
+	//	d.AutoClose = HTMLAutoClose;
+	//	d.Entity = HTMLEntity
 	//
 	// creates a parser that can handle typical HTML.
 	Strict bool
@@ -184,16 +184,16 @@ type Parser struct {
 	tmp       [32]byte
 }
 
-// NewParser creates a new XML parser reading from r.
-func NewParser(r io.Reader) *Parser {
-	p := &Parser{
+// NewDecoder creates a new XML parser reading from r.
+func NewDecoder(r io.Reader) *Decoder {
+	d := &Decoder{
 		ns:       make(map[string]string),
 		nextByte: -1,
 		line:     1,
 		Strict:   true,
 	}
-	p.switchToReader(r)
-	return p
+	d.switchToReader(r)
+	return d
 }
 
 // Token returns the next XML token in the input stream.
@@ -218,17 +218,17 @@ func NewParser(r io.Reader) *Parser {
 // set to the URL identifying its name space when known.
 // If Token encounters an unrecognized name space prefix,
 // it uses the prefix as the Space rather than report an error.
-func (p *Parser) Token() (t Token, err error) {
-	if p.nextToken != nil {
-		t = p.nextToken
-		p.nextToken = nil
-	} else if t, err = p.RawToken(); err != nil {
+func (d *Decoder) Token() (t Token, err error) {
+	if d.nextToken != nil {
+		t = d.nextToken
+		d.nextToken = nil
+	} else if t, err = d.RawToken(); err != nil {
 		return
 	}
 
-	if !p.Strict {
-		if t1, ok := p.autoClose(t); ok {
-			p.nextToken = t
+	if !d.Strict {
+		if t1, ok := d.autoClose(t); ok {
+			d.nextToken = t
 			t = t1
 		}
 	}
@@ -240,29 +240,29 @@ func (p *Parser) Token() (t Token, err error) {
 		// the translations first.
 		for _, a := range t1.Attr {
 			if a.Name.Space == "xmlns" {
-				v, ok := p.ns[a.Name.Local]
-				p.pushNs(a.Name.Local, v, ok)
-				p.ns[a.Name.Local] = a.Value
+				v, ok := d.ns[a.Name.Local]
+				d.pushNs(a.Name.Local, v, ok)
+				d.ns[a.Name.Local] = a.Value
 			}
 			if a.Name.Space == "" && a.Name.Local == "xmlns" {
 				// Default space for untagged names
-				v, ok := p.ns[""]
-				p.pushNs("", v, ok)
-				p.ns[""] = a.Value
+				v, ok := d.ns[""]
+				d.pushNs("", v, ok)
+				d.ns[""] = a.Value
 			}
 		}
 
-		p.translate(&t1.Name, true)
+		d.translate(&t1.Name, true)
 		for i := range t1.Attr {
-			p.translate(&t1.Attr[i].Name, false)
+			d.translate(&t1.Attr[i].Name, false)
 		}
-		p.pushElement(t1.Name)
+		d.pushElement(t1.Name)
 		t = t1
 
 	case EndElement:
-		p.translate(&t1.Name, true)
-		if !p.popElement(&t1) {
-			return nil, p.err
+		d.translate(&t1.Name, true)
+		if !d.popElement(&t1) {
+			return nil, d.err
 		}
 		t = t1
 	}
@@ -272,7 +272,7 @@ func (p *Parser) Token() (t Token, err error) {
 // Apply name space translation to name n.
 // The default name space (for Space=="")
 // applies only to element names, not to attribute names.
-func (p *Parser) translate(n *Name, isElementName bool) {
+func (d *Decoder) translate(n *Name, isElementName bool) {
 	switch {
 	case n.Space == "xmlns":
 		return
@@ -281,20 +281,20 @@ func (p *Parser) translate(n *Name, isElementName bool) {
 	case n.Space == "" && n.Local == "xmlns":
 		return
 	}
-	if v, ok := p.ns[n.Space]; ok {
+	if v, ok := d.ns[n.Space]; ok {
 		n.Space = v
 	}
 }
 
-func (p *Parser) switchToReader(r io.Reader) {
+func (d *Decoder) switchToReader(r io.Reader) {
 	// Get efficient byte at a time reader.
 	// Assume that if reader has its own
 	// ReadByte, it's efficient enough.
 	// Otherwise, use bufio.
 	if rb, ok := r.(io.ByteReader); ok {
-		p.r = rb
+		d.r = rb
 	} else {
-		p.r = bufio.NewReader(r)
+		d.r = bufio.NewReader(r)
 	}
 }
 
@@ -314,47 +314,47 @@ const (
 	stkNs
 )
 
-func (p *Parser) push(kind int) *stack {
-	s := p.free
+func (d *Decoder) push(kind int) *stack {
+	s := d.free
 	if s != nil {
-		p.free = s.next
+		d.free = s.next
 	} else {
 		s = new(stack)
 	}
-	s.next = p.stk
+	s.next = d.stk
 	s.kind = kind
-	p.stk = s
+	d.stk = s
 	return s
 }
 
-func (p *Parser) pop() *stack {
-	s := p.stk
+func (d *Decoder) pop() *stack {
+	s := d.stk
 	if s != nil {
-		p.stk = s.next
-		s.next = p.free
-		p.free = s
+		d.stk = s.next
+		s.next = d.free
+		d.free = s
 	}
 	return s
 }
 
 // Record that we are starting an element with the given name.
-func (p *Parser) pushElement(name Name) {
-	s := p.push(stkStart)
+func (d *Decoder) pushElement(name Name) {
+	s := d.push(stkStart)
 	s.name = name
 }
 
 // Record that we are changing the value of ns[local].
 // The old value is url, ok.
-func (p *Parser) pushNs(local string, url string, ok bool) {
-	s := p.push(stkNs)
+func (d *Decoder) pushNs(local string, url string, ok bool) {
+	s := d.push(stkNs)
 	s.name.Local = local
 	s.name.Space = url
 	s.ok = ok
 }
 
 // Creates a SyntaxError with the current line number.
-func (p *Parser) syntaxError(msg string) error {
-	return &SyntaxError{Msg: msg, Line: p.line}
+func (d *Decoder) syntaxError(msg string) error {
+	return &SyntaxError{Msg: msg, Line: d.line}
 }
 
 // Record that we are ending an element with the given name.
@@ -363,36 +363,36 @@ func (p *Parser) syntaxError(msg string) error {
 // After popping the element, apply any undo records from
 // the stack to restore the name translations that existed
 // before we saw this element.
-func (p *Parser) popElement(t *EndElement) bool {
-	s := p.pop()
+func (d *Decoder) popElement(t *EndElement) bool {
+	s := d.pop()
 	name := t.Name
 	switch {
 	case s == nil || s.kind != stkStart:
-		p.err = p.syntaxError("unexpected end element </" + name.Local + ">")
+		d.err = d.syntaxError("unexpected end element </" + name.Local + ">")
 		return false
 	case s.name.Local != name.Local:
-		if !p.Strict {
-			p.needClose = true
-			p.toClose = t.Name
+		if !d.Strict {
+			d.needClose = true
+			d.toClose = t.Name
 			t.Name = s.name
 			return true
 		}
-		p.err = p.syntaxError("element <" + s.name.Local + "> closed by </" + name.Local + ">")
+		d.err = d.syntaxError("element <" + s.name.Local + "> closed by </" + name.Local + ">")
 		return false
 	case s.name.Space != name.Space:
-		p.err = p.syntaxError("element <" + s.name.Local + "> in space " + s.name.Space +
+		d.err = d.syntaxError("element <" + s.name.Local + "> in space " + s.name.Space +
 			"closed by </" + name.Local + "> in space " + name.Space)
 		return false
 	}
 
 	// Pop stack until a Start is on the top, undoing the
 	// translations that were associated with the element we just closed.
-	for p.stk != nil && p.stk.kind != stkStart {
-		s := p.pop()
+	for d.stk != nil && d.stk.kind != stkStart {
+		s := d.pop()
 		if s.ok {
-			p.ns[s.name.Local] = s.name.Space
+			d.ns[s.name.Local] = s.name.Space
 		} else {
-			delete(p.ns, s.name.Local)
+			delete(d.ns, s.name.Local)
 		}
 	}
 
@@ -401,17 +401,17 @@ func (p *Parser) popElement(t *EndElement) bool {
 
 // If the top element on the stack is autoclosing and
 // t is not the end tag, invent the end tag.
-func (p *Parser) autoClose(t Token) (Token, bool) {
-	if p.stk == nil || p.stk.kind != stkStart {
+func (d *Decoder) autoClose(t Token) (Token, bool) {
+	if d.stk == nil || d.stk.kind != stkStart {
 		return nil, false
 	}
-	name := strings.ToLower(p.stk.name.Local)
-	for _, s := range p.AutoClose {
+	name := strings.ToLower(d.stk.name.Local)
+	for _, s := range d.AutoClose {
 		if strings.ToLower(s) == name {
 			// This one should be auto closed if t doesn't close it.
 			et, ok := t.(EndElement)
 			if !ok || et.Name.Local != name {
-				return EndElement{p.stk.name}, true
+				return EndElement{d.stk.name}, true
 			}
 			break
 		}
@@ -422,53 +422,53 @@ func (p *Parser) autoClose(t Token) (Token, bool) {
 // RawToken is like Token but does not verify that
 // start and end elements match and does not translate
 // name space prefixes to their corresponding URLs.
-func (p *Parser) RawToken() (Token, error) {
-	if p.err != nil {
-		return nil, p.err
+func (d *Decoder) RawToken() (Token, error) {
+	if d.err != nil {
+		return nil, d.err
 	}
-	if p.needClose {
+	if d.needClose {
 		// The last element we read was self-closing and
 		// we returned just the StartElement half.
 		// Return the EndElement half now.
-		p.needClose = false
-		return EndElement{p.toClose}, nil
+		d.needClose = false
+		return EndElement{d.toClose}, nil
 	}
 
-	b, ok := p.getc()
+	b, ok := d.getc()
 	if !ok {
-		return nil, p.err
+		return nil, d.err
 	}
 
 	if b != '<' {
 		// Text section.
-		p.ungetc(b)
-		data := p.text(-1, false)
+		d.ungetc(b)
+		data := d.text(-1, false)
 		if data == nil {
-			return nil, p.err
+			return nil, d.err
 		}
 		return CharData(data), nil
 	}
 
-	if b, ok = p.mustgetc(); !ok {
-		return nil, p.err
+	if b, ok = d.mustgetc(); !ok {
+		return nil, d.err
 	}
 	switch b {
 	case '/':
 		// </: End element
 		var name Name
-		if name, ok = p.nsname(); !ok {
-			if p.err == nil {
-				p.err = p.syntaxError("expected element name after </")
+		if name, ok = d.nsname(); !ok {
+			if d.err == nil {
+				d.err = d.syntaxError("expected element name after </")
 			}
-			return nil, p.err
+			return nil, d.err
 		}
-		p.space()
-		if b, ok = p.mustgetc(); !ok {
-			return nil, p.err
+		d.space()
+		if b, ok = d.mustgetc(); !ok {
+			return nil, d.err
 		}
 		if b != '>' {
-			p.err = p.syntaxError("invalid characters between </" + name.Local + " and >")
-			return nil, p.err
+			d.err = d.syntaxError("invalid characters between </" + name.Local + " and >")
+			return nil, d.err
 		}
 		return EndElement{name}, nil
 
@@ -477,95 +477,95 @@ func (p *Parser) RawToken() (Token, error) {
 		// TODO(rsc): Should parse the <?xml declaration to make sure
 		// the version is 1.0 and the encoding is UTF-8.
 		var target string
-		if target, ok = p.name(); !ok {
-			if p.err == nil {
-				p.err = p.syntaxError("expected target name after <?")
+		if target, ok = d.name(); !ok {
+			if d.err == nil {
+				d.err = d.syntaxError("expected target name after <?")
 			}
-			return nil, p.err
+			return nil, d.err
 		}
-		p.space()
-		p.buf.Reset()
+		d.space()
+		d.buf.Reset()
 		var b0 byte
 		for {
-			if b, ok = p.mustgetc(); !ok {
-				return nil, p.err
+			if b, ok = d.mustgetc(); !ok {
+				return nil, d.err
 			}
-			p.buf.WriteByte(b)
+			d.buf.WriteByte(b)
 			if b0 == '?' && b == '>' {
 				break
 			}
 			b0 = b
 		}
-		data := p.buf.Bytes()
+		data := d.buf.Bytes()
 		data = data[0 : len(data)-2] // chop ?>
 
 		if target == "xml" {
 			enc := procInstEncoding(string(data))
 			if enc != "" && enc != "utf-8" && enc != "UTF-8" {
-				if p.CharsetReader == nil {
-					p.err = fmt.Errorf("xml: encoding %q declared but Parser.CharsetReader is nil", enc)
-					return nil, p.err
+				if d.CharsetReader == nil {
+					d.err = fmt.Errorf("xml: encoding %q declared but Decoder.CharsetReader is nil", enc)
+					return nil, d.err
 				}
-				newr, err := p.CharsetReader(enc, p.r.(io.Reader))
+				newr, err := d.CharsetReader(enc, d.r.(io.Reader))
 				if err != nil {
-					p.err = fmt.Errorf("xml: opening charset %q: %v", enc, err)
-					return nil, p.err
+					d.err = fmt.Errorf("xml: opening charset %q: %v", enc, err)
+					return nil, d.err
 				}
 				if newr == nil {
 					panic("CharsetReader returned a nil Reader for charset " + enc)
 				}
-				p.switchToReader(newr)
+				d.switchToReader(newr)
 			}
 		}
 		return ProcInst{target, data}, nil
 
 	case '!':
 		// <!: Maybe comment, maybe CDATA.
-		if b, ok = p.mustgetc(); !ok {
-			return nil, p.err
+		if b, ok = d.mustgetc(); !ok {
+			return nil, d.err
 		}
 		switch b {
 		case '-': // <!-
 			// Probably <!-- for a comment.
-			if b, ok = p.mustgetc(); !ok {
-				return nil, p.err
+			if b, ok = d.mustgetc(); !ok {
+				return nil, d.err
 			}
 			if b != '-' {
-				p.err = p.syntaxError("invalid sequence <!- not part of <!--")
-				return nil, p.err
+				d.err = d.syntaxError("invalid sequence <!- not part of <!--")
+				return nil, d.err
 			}
 			// Look for terminator.
-			p.buf.Reset()
+			d.buf.Reset()
 			var b0, b1 byte
 			for {
-				if b, ok = p.mustgetc(); !ok {
-					return nil, p.err
+				if b, ok = d.mustgetc(); !ok {
+					return nil, d.err
 				}
-				p.buf.WriteByte(b)
+				d.buf.WriteByte(b)
 				if b0 == '-' && b1 == '-' && b == '>' {
 					break
 				}
 				b0, b1 = b1, b
 			}
-			data := p.buf.Bytes()
+			data := d.buf.Bytes()
 			data = data[0 : len(data)-3] // chop -->
 			return Comment(data), nil
 
 		case '[': // <![
 			// Probably <![CDATA[.
 			for i := 0; i < 6; i++ {
-				if b, ok = p.mustgetc(); !ok {
-					return nil, p.err
+				if b, ok = d.mustgetc(); !ok {
+					return nil, d.err
 				}
 				if b != "CDATA["[i] {
-					p.err = p.syntaxError("invalid <![ sequence")
-					return nil, p.err
+					d.err = d.syntaxError("invalid <![ sequence")
+					return nil, d.err
 				}
 			}
 			// Have <![CDATA[.  Read text until ]]>.
-			data := p.text(-1, true)
+			data := d.text(-1, true)
 			if data == nil {
-				return nil, p.err
+				return nil, d.err
 			}
 			return CharData(data), nil
 		}
@@ -573,18 +573,18 @@ func (p *Parser) RawToken() (Token, error) {
 		// Probably a directive: <!DOCTYPE ...>, <!ENTITY ...>, etc.
 		// We don't care, but accumulate for caller. Quoted angle
 		// brackets do not count for nesting.
-		p.buf.Reset()
-		p.buf.WriteByte(b)
+		d.buf.Reset()
+		d.buf.WriteByte(b)
 		inquote := uint8(0)
 		depth := 0
 		for {
-			if b, ok = p.mustgetc(); !ok {
-				return nil, p.err
+			if b, ok = d.mustgetc(); !ok {
+				return nil, d.err
 			}
 			if inquote == 0 && b == '>' && depth == 0 {
 				break
 			}
-			p.buf.WriteByte(b)
+			d.buf.WriteByte(b)
 			switch {
 			case b == inquote:
 				inquote = 0
@@ -602,45 +602,45 @@ func (p *Parser) RawToken() (Token, error) {
 				depth++
 			}
 		}
-		return Directive(p.buf.Bytes()), nil
+		return Directive(d.buf.Bytes()), nil
 	}
 
 	// Must be an open element like <a href="foo">
-	p.ungetc(b)
+	d.ungetc(b)
 
 	var (
 		name  Name
 		empty bool
 		attr  []Attr
 	)
-	if name, ok = p.nsname(); !ok {
-		if p.err == nil {
-			p.err = p.syntaxError("expected element name after <")
+	if name, ok = d.nsname(); !ok {
+		if d.err == nil {
+			d.err = d.syntaxError("expected element name after <")
 		}
-		return nil, p.err
+		return nil, d.err
 	}
 
 	attr = make([]Attr, 0, 4)
 	for {
-		p.space()
-		if b, ok = p.mustgetc(); !ok {
-			return nil, p.err
+		d.space()
+		if b, ok = d.mustgetc(); !ok {
+			return nil, d.err
 		}
 		if b == '/' {
 			empty = true
-			if b, ok = p.mustgetc(); !ok {
-				return nil, p.err
+			if b, ok = d.mustgetc(); !ok {
+				return nil, d.err
 			}
 			if b != '>' {
-				p.err = p.syntaxError("expected /> in element")
-				return nil, p.err
+				d.err = d.syntaxError("expected /> in element")
+				return nil, d.err
 			}
 			break
 		}
 		if b == '>' {
 			break
 		}
-		p.ungetc(b)
+		d.ungetc(b)
 
 		n := len(attr)
 		if n >= cap(attr) {
@@ -650,85 +650,85 @@ func (p *Parser) RawToken() (Token, error) {
 		}
 		attr = attr[0 : n+1]
 		a := &attr[n]
-		if a.Name, ok = p.nsname(); !ok {
-			if p.err == nil {
-				p.err = p.syntaxError("expected attribute name in element")
+		if a.Name, ok = d.nsname(); !ok {
+			if d.err == nil {
+				d.err = d.syntaxError("expected attribute name in element")
 			}
-			return nil, p.err
+			return nil, d.err
 		}
-		p.space()
-		if b, ok = p.mustgetc(); !ok {
-			return nil, p.err
+		d.space()
+		if b, ok = d.mustgetc(); !ok {
+			return nil, d.err
 		}
 		if b != '=' {
-			if p.Strict {
-				p.err = p.syntaxError("attribute name without = in element")
-				return nil, p.err
+			if d.Strict {
+				d.err = d.syntaxError("attribute name without = in element")
+				return nil, d.err
 			} else {
-				p.ungetc(b)
+				d.ungetc(b)
 				a.Value = a.Name.Local
 			}
 		} else {
-			p.space()
-			data := p.attrval()
+			d.space()
+			data := d.attrval()
 			if data == nil {
-				return nil, p.err
+				return nil, d.err
 			}
 			a.Value = string(data)
 		}
 	}
 	if empty {
-		p.needClose = true
-		p.toClose = name
+		d.needClose = true
+		d.toClose = name
 	}
 	return StartElement{name, attr}, nil
 }
 
-func (p *Parser) attrval() []byte {
-	b, ok := p.mustgetc()
+func (d *Decoder) attrval() []byte {
+	b, ok := d.mustgetc()
 	if !ok {
 		return nil
 	}
 	// Handle quoted attribute values
 	if b == '"' || b == '\'' {
-		return p.text(int(b), false)
+		return d.text(int(b), false)
 	}
 	// Handle unquoted attribute values for strict parsers
-	if p.Strict {
-		p.err = p.syntaxError("unquoted or missing attribute value in element")
+	if d.Strict {
+		d.err = d.syntaxError("unquoted or missing attribute value in element")
 		return nil
 	}
 	// Handle unquoted attribute values for unstrict parsers
-	p.ungetc(b)
-	p.buf.Reset()
+	d.ungetc(b)
+	d.buf.Reset()
 	for {
-		b, ok = p.mustgetc()
+		b, ok = d.mustgetc()
 		if !ok {
 			return nil
 		}
 		// http://www.w3.org/TR/REC-html40/intro/sgmltut.html#h-3.2.2
 		if 'a' <= b && b <= 'z' || 'A' <= b && b <= 'Z' ||
 			'0' <= b && b <= '9' || b == '_' || b == ':' || b == '-' {
-			p.buf.WriteByte(b)
+			d.buf.WriteByte(b)
 		} else {
-			p.ungetc(b)
+			d.ungetc(b)
 			break
 		}
 	}
-	return p.buf.Bytes()
+	return d.buf.Bytes()
 }
 
 // Skip spaces if any
-func (p *Parser) space() {
+func (d *Decoder) space() {
 	for {
-		b, ok := p.getc()
+		b, ok := d.getc()
 		if !ok {
 			return
 		}
 		switch b {
 		case ' ', '\r', '\n', '\t':
 		default:
-			p.ungetc(b)
+			d.ungetc(b)
 			return
 		}
 	}
@@ -736,35 +736,35 @@ func (p *Parser) space() {
 
 // Read a single byte.
 // If there is no byte to read, return ok==false
-// and leave the error in p.err.
+// and leave the error in d.err.
 // Maintain line number.
-func (p *Parser) getc() (b byte, ok bool) {
-	if p.err != nil {
+func (d *Decoder) getc() (b byte, ok bool) {
+	if d.err != nil {
 		return 0, false
 	}
-	if p.nextByte >= 0 {
-		b = byte(p.nextByte)
-		p.nextByte = -1
+	if d.nextByte >= 0 {
+		b = byte(d.nextByte)
+		d.nextByte = -1
 	} else {
-		b, p.err = p.r.ReadByte()
-		if p.err != nil {
+		b, d.err = d.r.ReadByte()
+		if d.err != nil {
 			return 0, false
 		}
-		if p.saved != nil {
-			p.saved.WriteByte(b)
+		if d.saved != nil {
+			d.saved.WriteByte(b)
 		}
 	}
 	if b == '\n' {
-		p.line++
+		d.line++
 	}
 	return b, true
 }
 
 // Return saved offset.
 // If we did ungetc (nextByte >= 0), have to back up one.
-func (p *Parser) savedOffset() int {
-	n := p.saved.Len()
-	if p.nextByte >= 0 {
+func (d *Decoder) savedOffset() int {
+	n := d.saved.Len()
+	if d.nextByte >= 0 {
 		n--
 	}
 	return n
@@ -772,23 +772,23 @@ func (p *Parser) savedOffset() int {
 
 // Must read a single byte.
 // If there is no byte to read,
-// set p.err to SyntaxError("unexpected EOF")
+// set d.err to SyntaxError("unexpected EOF")
 // and return ok==false
-func (p *Parser) mustgetc() (b byte, ok bool) {
-	if b, ok = p.getc(); !ok {
-		if p.err == io.EOF {
-			p.err = p.syntaxError("unexpected EOF")
+func (d *Decoder) mustgetc() (b byte, ok bool) {
+	if b, ok = d.getc(); !ok {
+		if d.err == io.EOF {
+			d.err = d.syntaxError("unexpected EOF")
 		}
 	}
 	return
 }
 
 // Unread a single byte.
-func (p *Parser) ungetc(b byte) {
+func (d *Decoder) ungetc(b byte) {
 	if b == '\n' {
-		p.line--
+		d.line--
 	}
-	p.nextByte = int(b)
+	d.nextByte = int(b)
 }
 
 var entity = map[string]int{
@@ -802,18 +802,18 @@ var entity = map[string]int{
 // Read plain text section (XML calls it character data).
 // If quote >= 0, we are in a quoted string and need to find the matching quote.
 // If cdata == true, we are in a <![CDATA[ section and need to find ]]>.
-// On failure return nil and leave the error in p.err.
-func (p *Parser) text(quote int, cdata bool) []byte {
+// On failure return nil and leave the error in d.err.
+func (d *Decoder) text(quote int, cdata bool) []byte {
 	var b0, b1 byte
 	var trunc int
-	p.buf.Reset()
+	d.buf.Reset()
 Input:
 	for {
-		b, ok := p.getc()
+		b, ok := d.getc()
 		if !ok {
 			if cdata {
-				if p.err == io.EOF {
-					p.err = p.syntaxError("unexpected EOF in CDATA section")
+				if d.err == io.EOF {
+					d.err = d.syntaxError("unexpected EOF in CDATA section")
 				}
 				return nil
 			}
@@ -827,17 +827,17 @@ Input:
 				trunc = 2
 				break Input
 			}
-			p.err = p.syntaxError("unescaped ]]> not in CDATA section")
+			d.err = d.syntaxError("unescaped ]]> not in CDATA section")
 			return nil
 		}
 
 		// Stop reading text if we see a <.
 		if b == '<' && !cdata {
 			if quote >= 0 {
-				p.err = p.syntaxError("unescaped < inside quoted string")
+				d.err = d.syntaxError("unescaped < inside quoted string")
 				return nil
 			}
-			p.ungetc('<')
+			d.ungetc('<')
 			break Input
 		}
 		if quote >= 0 && b == byte(quote) {
@@ -850,16 +850,16 @@ Input:
 			// Parsers are required to recognize lt, gt, amp, apos, and quot
 			// even if they have not been declared.  That's all we allow.
 			var i int
-			for i = 0; i < len(p.tmp); i++ {
+			for i = 0; i < len(d.tmp); i++ {
 				var ok bool
-				p.tmp[i], ok = p.getc()
+				d.tmp[i], ok = d.getc()
 				if !ok {
-					if p.err == io.EOF {
-						p.err = p.syntaxError("unexpected EOF")
+					if d.err == io.EOF {
+						d.err = d.syntaxError("unexpected EOF")
 					}
 					return nil
 				}
-				c := p.tmp[i]
+				c := d.tmp[i]
 				if c == ';' {
 					break
 				}
@@ -869,18 +869,18 @@ Input:
 					c == '_' || c == '#' {
 					continue
 				}
-				p.ungetc(c)
+				d.ungetc(c)
 				break
 			}
-			s := string(p.tmp[0:i])
-			if i >= len(p.tmp) {
-				if !p.Strict {
+			s := string(d.tmp[0:i])
+			if i >= len(d.tmp) {
+				if !d.Strict {
 					b0, b1 = 0, 0
-					p.buf.WriteByte('&')
-					p.buf.Write(p.tmp[0:i])
+					d.buf.WriteByte('&')
+					d.buf.Write(d.tmp[0:i])
 					continue Input
 				}
-				p.err = p.syntaxError("character entity expression &" + s + "... too long")
+				d.err = d.syntaxError("character entity expression &" + s + "... too long")
 				return nil
 			}
 			var haveText bool
@@ -901,28 +901,28 @@ Input:
 				if r, ok := entity[s]; ok {
 					text = string(r)
 					haveText = true
-				} else if p.Entity != nil {
-					text, haveText = p.Entity[s]
+				} else if d.Entity != nil {
+					text, haveText = d.Entity[s]
 				}
 			}
 			if !haveText {
-				if !p.Strict {
+				if !d.Strict {
 					b0, b1 = 0, 0
-					p.buf.WriteByte('&')
-					p.buf.Write(p.tmp[0:i])
+					d.buf.WriteByte('&')
+					d.buf.Write(d.tmp[0:i])
 					continue Input
 				}
-				p.err = p.syntaxError("invalid character entity &" + s + ";")
+				d.err = d.syntaxError("invalid character entity &" + s + ";")
 				return nil
 			}
-			p.buf.Write([]byte(text))
+			d.buf.Write([]byte(text))
 			b0, b1 = 0, 0
 			continue Input
 		}
-		p.buf.WriteByte(b)
+		d.buf.WriteByte(b)
 		b0, b1 = b1, b
 	}
-	data := p.buf.Bytes()
+	data := d.buf.Bytes()
 	data = data[0 : len(data)-trunc]
 
 	// Inspect each rune for being a disallowed character.
@@ -930,12 +930,12 @@ Input:
 	for len(buf) > 0 {
 		r, size := utf8.DecodeRune(buf)
 		if r == utf8.RuneError && size == 1 {
-			p.err = p.syntaxError("invalid UTF-8")
+			d.err = d.syntaxError("invalid UTF-8")
 			return nil
 		}
 		buf = buf[size:]
 		if !isInCharacterRange(r) {
-			p.err = p.syntaxError(fmt.Sprintf("illegal character code %U", r))
+			d.err = d.syntaxError(fmt.Sprintf("illegal character code %U", r))
 			return nil
 		}
 	}
@@ -970,8 +970,8 @@ func isInCharacterRange(r rune) (inrange bool) {
 
 // Get name space name: name with a : stuck in the middle.
 // The part before the : is the name space identifier.
-func (p *Parser) nsname() (name Name, ok bool) {
-	s, ok := p.name()
+func (d *Decoder) nsname() (name Name, ok bool) {
+	s, ok := d.name()
 	if !ok {
 		return
 	}
@@ -986,37 +986,37 @@ func (p *Parser) nsname() (name Name, ok bool) {
 }
 
 // Get name: /first(first|second)*/
-// Do not set p.err if the name is missing (unless unexpected EOF is received):
+// Do not set d.err if the name is missing (unless unexpected EOF is received):
 // let the caller provide better context.
-func (p *Parser) name() (s string, ok bool) {
+func (d *Decoder) name() (s string, ok bool) {
 	var b byte
-	if b, ok = p.mustgetc(); !ok {
+	if b, ok = d.mustgetc(); !ok {
 		return
 	}
 
 	// As a first approximation, we gather the bytes [A-Za-z_:.-\x80-\xFF]*
 	if b < utf8.RuneSelf && !isNameByte(b) {
-		p.ungetc(b)
+		d.ungetc(b)
 		return "", false
 	}
-	p.buf.Reset()
-	p.buf.WriteByte(b)
+	d.buf.Reset()
+	d.buf.WriteByte(b)
 	for {
-		if b, ok = p.mustgetc(); !ok {
+		if b, ok = d.mustgetc(); !ok {
 			return
 		}
 		if b < utf8.RuneSelf && !isNameByte(b) {
-			p.ungetc(b)
+			d.ungetc(b)
 			break
 		}
-		p.buf.WriteByte(b)
+		d.buf.WriteByte(b)
 	}
 
 	// Then we check the characters.
-	s = p.buf.String()
+	s = d.buf.String()
 	for i, c := range s {
 		if !unicode.Is(first, c) && (i == 0 || !unicode.Is(second, c)) {
-			p.err = p.syntaxError("invalid XML name: " + s)
+			d.err = d.syntaxError("invalid XML name: " + s)
 			return "", false
 		}
 	}

src/pkg/encoding/xml/xml_test.go

@@ -5,7 +5,6 @@
 package xml
 
 import (
-	"bytes"
 	"io"
 	"reflect"
 	"strings"
@@ -155,8 +154,8 @@ var xmlInput = []string{
 }
 
 func TestRawToken(t *testing.T) {
-	p := NewParser(strings.NewReader(testInput))
-	testRawToken(t, p, rawTokens)
+	d := NewDecoder(strings.NewReader(testInput))
+	testRawToken(t, d, rawTokens)
 }
 
 type downCaser struct {
@@ -179,27 +178,27 @@ func (d *downCaser) Read(p []byte) (int, error) {
 
 func TestRawTokenAltEncoding(t *testing.T) {
 	sawEncoding := ""
-	p := NewParser(strings.NewReader(testInputAltEncoding))
-	p.CharsetReader = func(charset string, input io.Reader) (io.Reader, error) {
+	d := NewDecoder(strings.NewReader(testInputAltEncoding))
+	d.CharsetReader = func(charset string, input io.Reader) (io.Reader, error) {
 		sawEncoding = charset
 		if charset != "x-testing-uppercase" {
 			t.Fatalf("unexpected charset %q", charset)
 		}
 		return &downCaser{t, input.(io.ByteReader)}, nil
 	}
-	testRawToken(t, p, rawTokensAltEncoding)
+	testRawToken(t, d, rawTokensAltEncoding)
 }
 
 func TestRawTokenAltEncodingNoConverter(t *testing.T) {
-	p := NewParser(strings.NewReader(testInputAltEncoding))
-	token, err := p.RawToken()
+	d := NewDecoder(strings.NewReader(testInputAltEncoding))
+	token, err := d.RawToken()
 	if token == nil {
 		t.Fatalf("expected a token on first RawToken call")
 	}
 	if err != nil {
 		t.Fatal(err)
 	}
-	token, err = p.RawToken()
+	token, err = d.RawToken()
 	if token != nil {
 		t.Errorf("expected a nil token; got %#v", token)
 	}
@@ -213,9 +212,9 @@ func TestRawTokenAltEncodingNoConverter(t *testing.T) {
 	}
 }
 
-func testRawToken(t *testing.T, p *Parser, rawTokens []Token) {
+func testRawToken(t *testing.T, d *Decoder, rawTokens []Token) {
 	for i, want := range rawTokens {
-		have, err := p.RawToken()
+		have, err := d.RawToken()
 		if err != nil {
 			t.Fatalf("token %d: unexpected error: %s", i, err)
 		}
@@ -258,10 +257,10 @@ var nestedDirectivesTokens = []Token{
 }
 
 func TestNestedDirectives(t *testing.T) {
-	p := NewParser(strings.NewReader(nestedDirectivesInput))
+	d := NewDecoder(strings.NewReader(nestedDirectivesInput))
 
 	for i, want := range nestedDirectivesTokens {
-		have, err := p.Token()
+		have, err := d.Token()
 		if err != nil {
 			t.Fatalf("token %d: unexpected error: %s", i, err)
 		}
@@ -272,10 +271,10 @@ func TestNestedDirectives(t *testing.T) {
 }
 
 func TestToken(t *testing.T) {
-	p := NewParser(strings.NewReader(testInput))
+	d := NewDecoder(strings.NewReader(testInput))
 
 	for i, want := range cookedTokens {
-		have, err := p.Token()
+		have, err := d.Token()
 		if err != nil {
 			t.Fatalf("token %d: unexpected error: %s", i, err)
 		}
@@ -287,9 +286,9 @@ func TestToken(t *testing.T) {
 
 func TestSyntax(t *testing.T) {
 	for i := range xmlInput {
-		p := NewParser(strings.NewReader(xmlInput[i]))
+		d := NewDecoder(strings.NewReader(xmlInput[i]))
 		var err error
-		for _, err = p.Token(); err == nil; _, err = p.Token() {
+		for _, err = d.Token(); err == nil; _, err = d.Token() {
 		}
 		if _, ok := err.(*SyntaxError); !ok {
 			t.Fatalf(`xmlInput "%s": expected SyntaxError not received`, xmlInput[i])
@@ -368,8 +367,7 @@ const testScalarsInput = `<allscalars>
 
 func TestAllScalars(t *testing.T) {
 	var a allScalars
-	buf := bytes.NewBufferString(testScalarsInput)
-	err := Unmarshal(buf, &a)
+	err := Unmarshal([]byte(testScalarsInput), &a)
 
 	if err != nil {
 		t.Fatal(err)
@@ -386,8 +384,7 @@ type item struct {
 func TestIssue569(t *testing.T) {
 	data := `<item><Field_a>abcd</Field_a></item>`
 	var i item
-	buf := bytes.NewBufferString(data)
-	err := Unmarshal(buf, &i)
+	err := Unmarshal([]byte(data), &i)
 
 	if err != nil || i.Field_a != "abcd" {
 		t.Fatal("Expecting abcd")
@@ -396,9 +393,9 @@ func TestIssue569(t *testing.T) {
 
 func TestUnquotedAttrs(t *testing.T) {
 	data := "<tag attr=azAZ09:-_\t>"
-	p := NewParser(strings.NewReader(data))
-	p.Strict = false
-	token, err := p.Token()
+	d := NewDecoder(strings.NewReader(data))
+	d.Strict = false
+	token, err := d.Token()
 	if _, ok := err.(*SyntaxError); ok {
 		t.Errorf("Unexpected error: %v", err)
 	}
@@ -422,9 +419,9 @@ func TestValuelessAttrs(t *testing.T) {
 		{"<input checked />", "input", "checked"},
 	}
 	for _, test := range tests {
-		p := NewParser(strings.NewReader(test[0]))
-		p.Strict = false
-		token, err := p.Token()
+		d := NewDecoder(strings.NewReader(test[0]))
+		d.Strict = false
+		token, err := d.Token()
 		if _, ok := err.(*SyntaxError); ok {
 			t.Errorf("Unexpected error: %v", err)
 		}
@@ -472,9 +469,9 @@ func TestCopyTokenStartElement(t *testing.T) {
 
 func TestSyntaxErrorLineNum(t *testing.T) {
 	testInput := "<P>Foo<P>\n\n<P>Bar</>\n"
-	p := NewParser(strings.NewReader(testInput))
+	d := NewDecoder(strings.NewReader(testInput))
 	var err error
-	for _, err = p.Token(); err == nil; _, err = p.Token() {
+	for _, err = d.Token(); err == nil; _, err = d.Token() {
 	}
 	synerr, ok := err.(*SyntaxError)
 	if !ok {
@@ -487,41 +484,41 @@ func TestSyntaxErrorLineNum(t *testing.T) {
 
 func TestTrailingRawToken(t *testing.T) {
 	input := `<FOO></FOO>  `
-	p := NewParser(strings.NewReader(input))
+	d := NewDecoder(strings.NewReader(input))
 	var err error
-	for _, err = p.RawToken(); err == nil; _, err = p.RawToken() {
+	for _, err = d.RawToken(); err == nil; _, err = d.RawToken() {
 	}
 	if err != io.EOF {
-		t.Fatalf("p.RawToken() = _, %v, want _, io.EOF", err)
+		t.Fatalf("d.RawToken() = _, %v, want _, io.EOF", err)
 	}
 }
 
 func TestTrailingToken(t *testing.T) {
 	input := `<FOO></FOO>  `
-	p := NewParser(strings.NewReader(input))
+	d := NewDecoder(strings.NewReader(input))
 	var err error
-	for _, err = p.Token(); err == nil; _, err = p.Token() {
+	for _, err = d.Token(); err == nil; _, err = d.Token() {
 	}
 	if err != io.EOF {
-		t.Fatalf("p.Token() = _, %v, want _, io.EOF", err)
+		t.Fatalf("d.Token() = _, %v, want _, io.EOF", err)
 	}
 }
 
 func TestEntityInsideCDATA(t *testing.T) {
 	input := `<test><![CDATA[ &val=foo ]]></test>`
-	p := NewParser(strings.NewReader(input))
+	d := NewDecoder(strings.NewReader(input))
 	var err error
-	for _, err = p.Token(); err == nil; _, err = p.Token() {
+	for _, err = d.Token(); err == nil; _, err = d.Token() {
 	}
 	if err != io.EOF {
-		t.Fatalf("p.Token() = _, %v, want _, io.EOF", err)
+		t.Fatalf("d.Token() = _, %v, want _, io.EOF", err)
 	}
 }
 
 // The last three tests (respectively one for characters in attribute
 // names and two for character entities) pass not because of code
 // changed for issue 1259, but instead pass with the given messages
-// from other parts of xml.Parser.  I provide these to note the
+// from other parts of xml.Decoder.  I provide these to note the
 // current behavior of situations where one might think that character
 // range checking would detect the error, but it does not in fact.
 
@@ -541,15 +538,15 @@ var characterTests = []struct {
 func TestDisallowedCharacters(t *testing.T) {
 
 	for i, tt := range characterTests {
-		p := NewParser(strings.NewReader(tt.in))
+		d := NewDecoder(strings.NewReader(tt.in))
 		var err error
 
 		for err == nil {
-			_, err = p.Token()
+			_, err = d.Token()
 		}
 		synerr, ok := err.(*SyntaxError)
 		if !ok {
-			t.Fatalf("input %d p.Token() = _, %v, want _, *SyntaxError", i, err)
+			t.Fatalf("input %d d.Token() = _, %v, want _, *SyntaxError", i, err)
 		}
 		if synerr.Msg != tt.err {
 			t.Fatalf("input %d synerr.Msg wrong: want '%s', got '%s'", i, tt.err, synerr.Msg)