Imported Upstream version 1.4upstream/1.4

9 files changed, 0 insertions, 3517 deletions

diff --git a/src/pkg/go/parser/error_test.go b/src/pkg/go/parser/error_test.go
deleted file mode 100644
index 8506077ce..000000000
--- a/src/pkg/go/parser/error_test.go
+++ /dev/null
@@ -1,183 +0,0 @@
-// 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.
-
-// This file implements a parser test harness. The files in the testdata
-// directory are parsed and the errors reported are compared against the
-// error messages expected in the test files. The test files must end in
-// .src rather than .go so that they are not disturbed by gofmt runs.
-//
-// Expected errors are indicated in the test files by putting a comment
-// of the form /* ERROR "rx" */ immediately following an offending token.
-// The harness will verify that an error matching the regular expression
-// rx is reported at that source position.
-//
-// For instance, the following test file indicates that a "not declared"
-// error should be reported for the undeclared variable x:
-//
-//	package p
-//	func f() {
-//		_ = x /* ERROR "not declared" */ + 1
-//	}
-
-package parser
-
-import (
-	"go/scanner"
-	"go/token"
-	"io/ioutil"
-	"path/filepath"
-	"regexp"
-	"strings"
-	"testing"
-)
-
-const testdata = "testdata"
-
-var fsetErrs *token.FileSet
-
-// getFile assumes that each filename occurs at most once
-func getFile(filename string) (file *token.File) {
-	fsetErrs.Iterate(func(f *token.File) bool {
-		if f.Name() == filename {
-			if file != nil {
-				panic(filename + " used multiple times")
-			}
-			file = f
-		}
-		return true
-	})
-	return file
-}
-
-func getPos(filename string, offset int) token.Pos {
-	if f := getFile(filename); f != nil {
-		return f.Pos(offset)
-	}
-	return token.NoPos
-}
-
-// ERROR comments must be of the form /* ERROR "rx" */ and rx is
-// a regular expression that matches the expected error message.
-// The special form /* ERROR HERE "rx" */ must be used for error
-// messages that appear immediately after a token, rather than at
-// a token's position.
-//
-var errRx = regexp.MustCompile(`^/\* *ERROR *(HERE)? *"([^"]*)" *\*/$`)
-
-// expectedErrors collects the regular expressions of ERROR comments found
-// in files and returns them as a map of error positions to error messages.
-//
-func expectedErrors(t *testing.T, filename string, src []byte) map[token.Pos]string {
-	errors := make(map[token.Pos]string)
-
-	var s scanner.Scanner
-	// file was parsed already - do not add it again to the file
-	// set otherwise the position information returned here will
-	// not match the position information collected by the parser
-	s.Init(getFile(filename), src, nil, scanner.ScanComments)
-	var prev token.Pos // position of last non-comment, non-semicolon token
-	var here token.Pos // position immediately after the token at position prev
-
-	for {
-		pos, tok, lit := s.Scan()
-		switch tok {
-		case token.EOF:
-			return errors
-		case token.COMMENT:
-			s := errRx.FindStringSubmatch(lit)
-			if len(s) == 3 {
-				pos := prev
-				if s[1] == "HERE" {
-					pos = here
-				}
-				errors[pos] = string(s[2])
-			}
-		default:
-			prev = pos
-			var l int // token length
-			if tok.IsLiteral() {
-				l = len(lit)
-			} else {
-				l = len(tok.String())
-			}
-			here = prev + token.Pos(l)
-		}
-	}
-}
-
-// compareErrors compares the map of expected error messages with the list
-// of found errors and reports discrepancies.
-//
-func compareErrors(t *testing.T, expected map[token.Pos]string, found scanner.ErrorList) {
-	for _, error := range found {
-		// error.Pos is a token.Position, but we want
-		// a token.Pos so we can do a map lookup
-		pos := getPos(error.Pos.Filename, error.Pos.Offset)
-		if msg, found := expected[pos]; found {
-			// we expect a message at pos; check if it matches
-			rx, err := regexp.Compile(msg)
-			if err != nil {
-				t.Errorf("%s: %v", error.Pos, err)
-				continue
-			}
-			if match := rx.MatchString(error.Msg); !match {
-				t.Errorf("%s: %q does not match %q", error.Pos, error.Msg, msg)
-				continue
-			}
-			// we have a match - eliminate this error
-			delete(expected, pos)
-		} else {
-			// To keep in mind when analyzing failed test output:
-			// If the same error position occurs multiple times in errors,
-			// this message will be triggered (because the first error at
-			// the position removes this position from the expected errors).
-			t.Errorf("%s: unexpected error: %s", error.Pos, error.Msg)
-		}
-	}
-
-	// there should be no expected errors left
-	if len(expected) > 0 {
-		t.Errorf("%d errors not reported:", len(expected))
-		for pos, msg := range expected {
-			t.Errorf("%s: %s\n", fsetErrs.Position(pos), msg)
-		}
-	}
-}
-
-func checkErrors(t *testing.T, filename string, input interface{}) {
-	src, err := readSource(filename, input)
-	if err != nil {
-		t.Error(err)
-		return
-	}
-
-	_, err = ParseFile(fsetErrs, filename, src, DeclarationErrors|AllErrors)
-	found, ok := err.(scanner.ErrorList)
-	if err != nil && !ok {
-		t.Error(err)
-		return
-	}
-	found.RemoveMultiples()
-
-	// we are expecting the following errors
-	// (collect these after parsing a file so that it is found in the file set)
-	expected := expectedErrors(t, filename, src)
-
-	// verify errors returned by the parser
-	compareErrors(t, expected, found)
-}
-
-func TestErrors(t *testing.T) {
-	fsetErrs = token.NewFileSet()
-	list, err := ioutil.ReadDir(testdata)
-	if err != nil {
-		t.Fatal(err)
-	}
-	for _, fi := range list {
-		name := fi.Name()
-		if !fi.IsDir() && !strings.HasPrefix(name, ".") && strings.HasSuffix(name, ".src") {
-			checkErrors(t, filepath.Join(testdata, name), nil)
-		}
-	}
-}
diff --git a/src/pkg/go/parser/example_test.go b/src/pkg/go/parser/example_test.go
deleted file mode 100644
index 3c58e63a9..000000000
--- a/src/pkg/go/parser/example_test.go
+++ /dev/null
@@ -1,34 +0,0 @@
-// 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 parser_test
-
-import (
-	"fmt"
-	"go/parser"
-	"go/token"
-)
-
-func ExampleParseFile() {
-	fset := token.NewFileSet() // positions are relative to fset
-
-	// Parse the file containing this very example
-	// but stop after processing the imports.
-	f, err := parser.ParseFile(fset, "example_test.go", nil, parser.ImportsOnly)
-	if err != nil {
-		fmt.Println(err)
-		return
-	}
-
-	// Print the imports from the file's AST.
-	for _, s := range f.Imports {
-		fmt.Println(s.Path.Value)
-	}
-
-	// output:
-	//
-	// "fmt"
-	// "go/parser"
-	// "go/token"
-}
diff --git a/src/pkg/go/parser/interface.go b/src/pkg/go/parser/interface.go
deleted file mode 100644
index 57da4ddcd..000000000
--- a/src/pkg/go/parser/interface.go
+++ /dev/null
@@ -1,198 +0,0 @@
-// 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.
-
-// This file contains the exported entry points for invoking the parser.
-
-package parser
-
-import (
-	"bytes"
-	"errors"
-	"go/ast"
-	"go/token"
-	"io"
-	"io/ioutil"
-	"os"
-	"path/filepath"
-	"strings"
-)
-
-// If src != nil, readSource converts src to a []byte if possible;
-// otherwise it returns an error. If src == nil, readSource returns
-// the result of reading the file specified by filename.
-//
-func readSource(filename string, src interface{}) ([]byte, error) {
-	if src != nil {
-		switch s := src.(type) {
-		case string:
-			return []byte(s), nil
-		case []byte:
-			return s, nil
-		case *bytes.Buffer:
-			// is io.Reader, but src is already available in []byte form
-			if s != nil {
-				return s.Bytes(), nil
-			}
-		case io.Reader:
-			var buf bytes.Buffer
-			if _, err := io.Copy(&buf, s); err != nil {
-				return nil, err
-			}
-			return buf.Bytes(), nil
-		}
-		return nil, errors.New("invalid source")
-	}
-	return ioutil.ReadFile(filename)
-}
-
-// A Mode value is a set of flags (or 0).
-// They control the amount of source code parsed and other optional
-// parser functionality.
-//
-type Mode uint
-
-const (
-	PackageClauseOnly Mode             = 1 << iota // stop parsing after package clause
-	ImportsOnly                                    // stop parsing after import declarations
-	ParseComments                                  // parse comments and add them to AST
-	Trace                                          // print a trace of parsed productions
-	DeclarationErrors                              // report declaration errors
-	SpuriousErrors                                 // same as AllErrors, for backward-compatibility
-	AllErrors         = SpuriousErrors             // report all errors (not just the first 10 on different lines)
-)
-
-// ParseFile parses the source code of a single Go source file and returns
-// the corresponding ast.File node. The source code may be provided via
-// the filename of the source file, or via the src parameter.
-//
-// If src != nil, ParseFile parses the source from src and the filename is
-// only used when recording position information. The type of the argument
-// for the src parameter must be string, []byte, or io.Reader.
-// If src == nil, ParseFile parses the file specified by filename.
-//
-// The mode parameter controls the amount of source text parsed and other
-// optional parser functionality. Position information is recorded in the
-// file set fset.
-//
-// If the source couldn't be read, the returned AST is nil and the error
-// indicates the specific failure. If the source was read but syntax
-// errors were found, the result is a partial AST (with ast.Bad* nodes
-// representing the fragments of erroneous source code). Multiple errors
-// are returned via a scanner.ErrorList which is sorted by file position.
-//
-func ParseFile(fset *token.FileSet, filename string, src interface{}, mode Mode) (f *ast.File, err error) {
-	// get source
-	text, err := readSource(filename, src)
-	if err != nil {
-		return nil, err
-	}
-
-	var p parser
-	defer func() {
-		if e := recover(); e != nil {
-			_ = e.(bailout) // re-panics if it's not a bailout
-		}
-
-		// set result values
-		if f == nil {
-			// source is not a valid Go source file - satisfy
-			// ParseFile API and return a valid (but) empty
-			// *ast.File
-			f = &ast.File{
-				Name:  new(ast.Ident),
-				Scope: ast.NewScope(nil),
-			}
-		}
-
-		p.errors.Sort()
-		err = p.errors.Err()
-	}()
-
-	// parse source
-	p.init(fset, filename, text, mode)
-	f = p.parseFile()
-
-	return
-}
-
-// ParseDir calls ParseFile for all files with names ending in ".go" in the
-// directory specified by path and returns a map of package name -> package
-// AST with all the packages found.
-//
-// If filter != nil, only the files with os.FileInfo entries passing through
-// the filter (and ending in ".go") are considered. The mode bits are passed
-// to ParseFile unchanged. Position information is recorded in fset.
-//
-// If the directory couldn't be read, a nil map and the respective error are
-// returned. If a parse error occurred, a non-nil but incomplete map and the
-// first error encountered are returned.
-//
-func ParseDir(fset *token.FileSet, path string, filter func(os.FileInfo) bool, mode Mode) (pkgs map[string]*ast.Package, first error) {
-	fd, err := os.Open(path)
-	if err != nil {
-		return nil, err
-	}
-	defer fd.Close()
-
-	list, err := fd.Readdir(-1)
-	if err != nil {
-		return nil, err
-	}
-
-	pkgs = make(map[string]*ast.Package)
-	for _, d := range list {
-		if strings.HasSuffix(d.Name(), ".go") && (filter == nil || filter(d)) {
-			filename := filepath.Join(path, d.Name())
-			if src, err := ParseFile(fset, filename, nil, mode); err == nil {
-				name := src.Name.Name
-				pkg, found := pkgs[name]
-				if !found {
-					pkg = &ast.Package{
-						Name:  name,
-						Files: make(map[string]*ast.File),
-					}
-					pkgs[name] = pkg
-				}
-				pkg.Files[filename] = src
-			} else if first == nil {
-				first = err
-			}
-		}
-	}
-
-	return
-}
-
-// ParseExpr is a convenience function for obtaining the AST of an expression x.
-// The position information recorded in the AST is undefined. The filename used
-// in error messages is the empty string.
-//
-func ParseExpr(x string) (ast.Expr, error) {
-	var p parser
-	p.init(token.NewFileSet(), "", []byte(x), 0)
-
-	// Set up pkg-level scopes to avoid nil-pointer errors.
-	// This is not needed for a correct expression x as the
-	// parser will be ok with a nil topScope, but be cautious
-	// in case of an erroneous x.
-	p.openScope()
-	p.pkgScope = p.topScope
-	e := p.parseRhsOrType()
-	p.closeScope()
-	assert(p.topScope == nil, "unbalanced scopes")
-
-	// If a semicolon was inserted, consume it;
-	// report an error if there's more tokens.
-	if p.tok == token.SEMICOLON {
-		p.next()
-	}
-	p.expect(token.EOF)
-
-	if p.errors.Len() > 0 {
-		p.errors.Sort()
-		return nil, p.errors.Err()
-	}
-
-	return e, nil
-}
diff --git a/src/pkg/go/parser/parser.go b/src/pkg/go/parser/parser.go
deleted file mode 100644
index 00dd532b2..000000000
--- a/src/pkg/go/parser/parser.go
+++ /dev/null
@@ -1,2478 +0,0 @@
-// 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.
-
-// Package parser implements a parser for Go source files. Input may be
-// provided in a variety of forms (see the various Parse* functions); the
-// output is an abstract syntax tree (AST) representing the Go source. The
-// parser is invoked through one of the Parse* functions.
-//
-package parser
-
-import (
-	"fmt"
-	"go/ast"
-	"go/scanner"
-	"go/token"
-	"strconv"
-	"strings"
-	"unicode"
-)
-
-// The parser structure holds the parser's internal state.
-type parser struct {
-	file    *token.File
-	errors  scanner.ErrorList
-	scanner scanner.Scanner
-
-	// Tracing/debugging
-	mode   Mode // parsing mode
-	trace  bool // == (mode & Trace != 0)
-	indent int  // indentation used for tracing output
-
-	// Comments
-	comments    []*ast.CommentGroup
-	leadComment *ast.CommentGroup // last lead comment
-	lineComment *ast.CommentGroup // last line comment
-
-	// Next token
-	pos token.Pos   // token position
-	tok token.Token // one token look-ahead
-	lit string      // token literal
-
-	// Error recovery
-	// (used to limit the number of calls to syncXXX functions
-	// w/o making scanning progress - avoids potential endless
-	// loops across multiple parser functions during error recovery)
-	syncPos token.Pos // last synchronization position
-	syncCnt int       // number of calls to syncXXX without progress
-
-	// Non-syntactic parser control
-	exprLev int  // < 0: in control clause, >= 0: in expression
-	inRhs   bool // if set, the parser is parsing a rhs expression
-
-	// Ordinary identifier scopes
-	pkgScope   *ast.Scope        // pkgScope.Outer == nil
-	topScope   *ast.Scope        // top-most scope; may be pkgScope
-	unresolved []*ast.Ident      // unresolved identifiers
-	imports    []*ast.ImportSpec // list of imports
-
-	// Label scopes
-	// (maintained by open/close LabelScope)
-	labelScope  *ast.Scope     // label scope for current function
-	targetStack [][]*ast.Ident // stack of unresolved labels
-}
-
-func (p *parser) init(fset *token.FileSet, filename string, src []byte, mode Mode) {
-	p.file = fset.AddFile(filename, -1, len(src))
-	var m scanner.Mode
-	if mode&ParseComments != 0 {
-		m = scanner.ScanComments
-	}
-	eh := func(pos token.Position, msg string) { p.errors.Add(pos, msg) }
-	p.scanner.Init(p.file, src, eh, m)
-
-	p.mode = mode
-	p.trace = mode&Trace != 0 // for convenience (p.trace is used frequently)
-
-	p.next()
-}
-
-// ----------------------------------------------------------------------------
-// Scoping support
-
-func (p *parser) openScope() {
-	p.topScope = ast.NewScope(p.topScope)
-}
-
-func (p *parser) closeScope() {
-	p.topScope = p.topScope.Outer
-}
-
-func (p *parser) openLabelScope() {
-	p.labelScope = ast.NewScope(p.labelScope)
-	p.targetStack = append(p.targetStack, nil)
-}
-
-func (p *parser) closeLabelScope() {
-	// resolve labels
-	n := len(p.targetStack) - 1
-	scope := p.labelScope
-	for _, ident := range p.targetStack[n] {
-		ident.Obj = scope.Lookup(ident.Name)
-		if ident.Obj == nil && p.mode&DeclarationErrors != 0 {
-			p.error(ident.Pos(), fmt.Sprintf("label %s undefined", ident.Name))
-		}
-	}
-	// pop label scope
-	p.targetStack = p.targetStack[0:n]
-	p.labelScope = p.labelScope.Outer
-}
-
-func (p *parser) declare(decl, data interface{}, scope *ast.Scope, kind ast.ObjKind, idents ...*ast.Ident) {
-	for _, ident := range idents {
-		assert(ident.Obj == nil, "identifier already declared or resolved")
-		obj := ast.NewObj(kind, ident.Name)
-		// remember the corresponding declaration for redeclaration
-		// errors and global variable resolution/typechecking phase
-		obj.Decl = decl
-		obj.Data = data
-		ident.Obj = obj
-		if ident.Name != "_" {
-			if alt := scope.Insert(obj); alt != nil && p.mode&DeclarationErrors != 0 {
-				prevDecl := ""
-				if pos := alt.Pos(); pos.IsValid() {
-					prevDecl = fmt.Sprintf("\n\tprevious declaration at %s", p.file.Position(pos))
-				}
-				p.error(ident.Pos(), fmt.Sprintf("%s redeclared in this block%s", ident.Name, prevDecl))
-			}
-		}
-	}
-}
-
-func (p *parser) shortVarDecl(decl *ast.AssignStmt, list []ast.Expr) {
-	// Go spec: A short variable declaration may redeclare variables
-	// provided they were originally declared in the same block with
-	// the same type, and at least one of the non-blank variables is new.
-	n := 0 // number of new variables
-	for _, x := range list {
-		if ident, isIdent := x.(*ast.Ident); isIdent {
-			assert(ident.Obj == nil, "identifier already declared or resolved")
-			obj := ast.NewObj(ast.Var, ident.Name)
-			// remember corresponding assignment for other tools
-			obj.Decl = decl
-			ident.Obj = obj
-			if ident.Name != "_" {
-				if alt := p.topScope.Insert(obj); alt != nil {
-					ident.Obj = alt // redeclaration
-				} else {
-					n++ // new declaration
-				}
-			}
-		} else {
-			p.errorExpected(x.Pos(), "identifier on left side of :=")
-		}
-	}
-	if n == 0 && p.mode&DeclarationErrors != 0 {
-		p.error(list[0].Pos(), "no new variables on left side of :=")
-	}
-}
-
-// The unresolved object is a sentinel to mark identifiers that have been added
-// to the list of unresolved identifiers. The sentinel is only used for verifying
-// internal consistency.
-var unresolved = new(ast.Object)
-
-// If x is an identifier, tryResolve attempts to resolve x by looking up
-// the object it denotes. If no object is found and collectUnresolved is
-// set, x is marked as unresolved and collected in the list of unresolved
-// identifiers.
-//
-func (p *parser) tryResolve(x ast.Expr, collectUnresolved bool) {
-	// nothing to do if x is not an identifier or the blank identifier
-	ident, _ := x.(*ast.Ident)
-	if ident == nil {
-		return
-	}
-	assert(ident.Obj == nil, "identifier already declared or resolved")
-	if ident.Name == "_" {
-		return
-	}
-	// try to resolve the identifier
-	for s := p.topScope; s != nil; s = s.Outer {
-		if obj := s.Lookup(ident.Name); obj != nil {
-			ident.Obj = obj
-			return
-		}
-	}
-	// all local scopes are known, so any unresolved identifier
-	// must be found either in the file scope, package scope
-	// (perhaps in another file), or universe scope --- collect
-	// them so that they can be resolved later
-	if collectUnresolved {
-		ident.Obj = unresolved
-		p.unresolved = append(p.unresolved, ident)
-	}
-}
-
-func (p *parser) resolve(x ast.Expr) {
-	p.tryResolve(x, true)
-}
-
-// ----------------------------------------------------------------------------
-// Parsing support
-
-func (p *parser) printTrace(a ...interface{}) {
-	const dots = ". . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . "
-	const n = len(dots)
-	pos := p.file.Position(p.pos)
-	fmt.Printf("%5d:%3d: ", pos.Line, pos.Column)
-	i := 2 * p.indent
-	for i > n {
-		fmt.Print(dots)
-		i -= n
-	}
-	// i <= n
-	fmt.Print(dots[0:i])
-	fmt.Println(a...)
-}
-
-func trace(p *parser, msg string) *parser {
-	p.printTrace(msg, "(")
-	p.indent++
-	return p
-}
-
-// Usage pattern: defer un(trace(p, "..."))
-func un(p *parser) {
-	p.indent--
-	p.printTrace(")")
-}
-
-// Advance to the next token.
-func (p *parser) next0() {
-	// Because of one-token look-ahead, print the previous token
-	// when tracing as it provides a more readable output. The
-	// very first token (!p.pos.IsValid()) is not initialized
-	// (it is token.ILLEGAL), so don't print it .
-	if p.trace && p.pos.IsValid() {
-		s := p.tok.String()
-		switch {
-		case p.tok.IsLiteral():
-			p.printTrace(s, p.lit)
-		case p.tok.IsOperator(), p.tok.IsKeyword():
-			p.printTrace("\"" + s + "\"")
-		default:
-			p.printTrace(s)
-		}
-	}
-
-	p.pos, p.tok, p.lit = p.scanner.Scan()
-}
-
-// Consume a comment and return it and the line on which it ends.
-func (p *parser) consumeComment() (comment *ast.Comment, endline int) {
-	// /*-style comments may end on a different line than where they start.
-	// Scan the comment for '\n' chars and adjust endline accordingly.
-	endline = p.file.Line(p.pos)
-	if p.lit[1] == '*' {
-		// don't use range here - no need to decode Unicode code points
-		for i := 0; i < len(p.lit); i++ {
-			if p.lit[i] == '\n' {
-				endline++
-			}
-		}
-	}
-
-	comment = &ast.Comment{Slash: p.pos, Text: p.lit}
-	p.next0()
-
-	return
-}
-
-// Consume a group of adjacent comments, add it to the parser's
-// comments list, and return it together with the line at which
-// the last comment in the group ends. A non-comment token or n
-// empty lines terminate a comment group.
-//
-func (p *parser) consumeCommentGroup(n int) (comments *ast.CommentGroup, endline int) {
-	var list []*ast.Comment
-	endline = p.file.Line(p.pos)
-	for p.tok == token.COMMENT && p.file.Line(p.pos) <= endline+n {
-		var comment *ast.Comment
-		comment, endline = p.consumeComment()
-		list = append(list, comment)
-	}
-
-	// add comment group to the comments list
-	comments = &ast.CommentGroup{List: list}
-	p.comments = append(p.comments, comments)
-
-	return
-}
-
-// Advance to the next non-comment token. In the process, collect
-// any comment groups encountered, and remember the last lead and
-// and line comments.
-//
-// A lead comment is a comment group that starts and ends in a
-// line without any other tokens and that is followed by a non-comment
-// token on the line immediately after the comment group.
-//
-// A line comment is a comment group that follows a non-comment
-// token on the same line, and that has no tokens after it on the line
-// where it ends.
-//
-// Lead and line comments may be considered documentation that is
-// stored in the AST.
-//
-func (p *parser) next() {
-	p.leadComment = nil
-	p.lineComment = nil
-	prev := p.pos
-	p.next0()
-
-	if p.tok == token.COMMENT {
-		var comment *ast.CommentGroup
-		var endline int
-
-		if p.file.Line(p.pos) == p.file.Line(prev) {
-			// The comment is on same line as the previous token; it
-			// cannot be a lead comment but may be a line comment.
-			comment, endline = p.consumeCommentGroup(0)
-			if p.file.Line(p.pos) != endline {
-				// The next token is on a different line, thus
-				// the last comment group is a line comment.
-				p.lineComment = comment
-			}
-		}
-
-		// consume successor comments, if any
-		endline = -1
-		for p.tok == token.COMMENT {
-			comment, endline = p.consumeCommentGroup(1)
-		}
-
-		if endline+1 == p.file.Line(p.pos) {
-			// The next token is following on the line immediately after the
-			// comment group, thus the last comment group is a lead comment.
-			p.leadComment = comment
-		}
-	}
-}
-
-// A bailout panic is raised to indicate early termination.
-type bailout struct{}
-
-func (p *parser) error(pos token.Pos, msg string) {
-	epos := p.file.Position(pos)
-
-	// If AllErrors is not set, discard errors reported on the same line
-	// as the last recorded error and stop parsing if there are more than
-	// 10 errors.
-	if p.mode&AllErrors == 0 {
-		n := len(p.errors)
-		if n > 0 && p.errors[n-1].Pos.Line == epos.Line {
-			return // discard - likely a spurious error
-		}
-		if n > 10 {
-			panic(bailout{})
-		}
-	}
-
-	p.errors.Add(epos, msg)
-}
-
-func (p *parser) errorExpected(pos token.Pos, msg string) {
-	msg = "expected " + msg
-	if pos == p.pos {
-		// the error happened at the current position;
-		// make the error message more specific
-		if p.tok == token.SEMICOLON && p.lit == "\n" {
-			msg += ", found newline"
-		} else {
-			msg += ", found '" + p.tok.String() + "'"
-			if p.tok.IsLiteral() {
-				msg += " " + p.lit
-			}
-		}
-	}
-	p.error(pos, msg)
-}
-
-func (p *parser) expect(tok token.Token) token.Pos {
-	pos := p.pos
-	if p.tok != tok {
-		p.errorExpected(pos, "'"+tok.String()+"'")
-	}
-	p.next() // make progress
-	return pos
-}
-
-// expectClosing is like expect but provides a better error message
-// for the common case of a missing comma before a newline.
-//
-func (p *parser) expectClosing(tok token.Token, context string) token.Pos {
-	if p.tok != tok && p.tok == token.SEMICOLON && p.lit == "\n" {
-		p.error(p.pos, "missing ',' before newline in "+context)
-		p.next()
-	}
-	return p.expect(tok)
-}
-
-func (p *parser) expectSemi() {
-	// semicolon is optional before a closing ')' or '}'
-	if p.tok != token.RPAREN && p.tok != token.RBRACE {
-		if p.tok == token.SEMICOLON {
-			p.next()
-		} else {
-			p.errorExpected(p.pos, "';'")
-			syncStmt(p)
-		}
-	}
-}
-
-func (p *parser) atComma(context string) bool {
-	if p.tok == token.COMMA {
-		return true
-	}
-	if p.tok == token.SEMICOLON && p.lit == "\n" {
-		p.error(p.pos, "missing ',' before newline in "+context)
-		return true // "insert" the comma and continue
-
-	}
-	return false
-}
-
-func assert(cond bool, msg string) {
-	if !cond {
-		panic("go/parser internal error: " + msg)
-	}
-}
-
-// syncStmt advances to the next statement.
-// Used for synchronization after an error.
-//
-func syncStmt(p *parser) {
-	for {
-		switch p.tok {
-		case token.BREAK, token.CONST, token.CONTINUE, token.DEFER,
-			token.FALLTHROUGH, token.FOR, token.GO, token.GOTO,
-			token.IF, token.RETURN, token.SELECT, token.SWITCH,
-			token.TYPE, token.VAR:
-			// Return only if parser made some progress since last
-			// sync or if it has not reached 10 sync calls without
-			// progress. Otherwise consume at least one token to
-			// avoid an endless parser loop (it is possible that
-			// both parseOperand and parseStmt call syncStmt and
-			// correctly do not advance, thus the need for the
-			// invocation limit p.syncCnt).
-			if p.pos == p.syncPos && p.syncCnt < 10 {
-				p.syncCnt++
-				return
-			}
-			if p.pos > p.syncPos {
-				p.syncPos = p.pos
-				p.syncCnt = 0
-				return
-			}
-			// Reaching here indicates a parser bug, likely an
-			// incorrect token list in this function, but it only
-			// leads to skipping of possibly correct code if a
-			// previous error is present, and thus is preferred
-			// over a non-terminating parse.
-		case token.EOF:
-			return
-		}
-		p.next()
-	}
-}
-
-// syncDecl advances to the next declaration.
-// Used for synchronization after an error.
-//
-func syncDecl(p *parser) {
-	for {
-		switch p.tok {
-		case token.CONST, token.TYPE, token.VAR:
-			// see comments in syncStmt
-			if p.pos == p.syncPos && p.syncCnt < 10 {
-				p.syncCnt++
-				return
-			}
-			if p.pos > p.syncPos {
-				p.syncPos = p.pos
-				p.syncCnt = 0
-				return
-			}
-		case token.EOF:
-			return
-		}
-		p.next()
-	}
-}
-
-// safePos returns a valid file position for a given position: If pos
-// is valid to begin with, safePos returns pos. If pos is out-of-range,
-// safePos returns the EOF position.
-//
-// This is hack to work around "artificial" end positions in the AST which
-// are computed by adding 1 to (presumably valid) token positions. If the
-// token positions are invalid due to parse errors, the resulting end position
-// may be past the file's EOF position, which would lead to panics if used
-// later on.
-//
-func (p *parser) safePos(pos token.Pos) (res token.Pos) {
-	defer func() {
-		if recover() != nil {
-			res = token.Pos(p.file.Base() + p.file.Size()) // EOF position
-		}
-	}()
-	_ = p.file.Offset(pos) // trigger a panic if position is out-of-range
-	return pos
-}
-
-// ----------------------------------------------------------------------------
-// Identifiers
-
-func (p *parser) parseIdent() *ast.Ident {
-	pos := p.pos
-	name := "_"
-	if p.tok == token.IDENT {
-		name = p.lit
-		p.next()
-	} else {
-		p.expect(token.IDENT) // use expect() error handling
-	}
-	return &ast.Ident{NamePos: pos, Name: name}
-}
-
-func (p *parser) parseIdentList() (list []*ast.Ident) {
-	if p.trace {
-		defer un(trace(p, "IdentList"))
-	}
-
-	list = append(list, p.parseIdent())
-	for p.tok == token.COMMA {
-		p.next()
-		list = append(list, p.parseIdent())
-	}
-
-	return
-}
-
-// ----------------------------------------------------------------------------
-// Common productions
-
-// If lhs is set, result list elements which are identifiers are not resolved.
-func (p *parser) parseExprList(lhs bool) (list []ast.Expr) {
-	if p.trace {
-		defer un(trace(p, "ExpressionList"))
-	}
-
-	list = append(list, p.checkExpr(p.parseExpr(lhs)))
-	for p.tok == token.COMMA {
-		p.next()
-		list = append(list, p.checkExpr(p.parseExpr(lhs)))
-	}
-
-	return
-}
-
-func (p *parser) parseLhsList() []ast.Expr {
-	old := p.inRhs
-	p.inRhs = false
-	list := p.parseExprList(true)
-	switch p.tok {
-	case token.DEFINE:
-		// lhs of a short variable declaration
-		// but doesn't enter scope until later:
-		// caller must call p.shortVarDecl(p.makeIdentList(list))
-		// at appropriate time.
-	case token.COLON:
-		// lhs of a label declaration or a communication clause of a select
-		// statement (parseLhsList is not called when parsing the case clause
-		// of a switch statement):
-		// - labels are declared by the caller of parseLhsList
-		// - for communication clauses, if there is a stand-alone identifier
-		//   followed by a colon, we have a syntax error; there is no need
-		//   to resolve the identifier in that case
-	default:
-		// identifiers must be declared elsewhere
-		for _, x := range list {
-			p.resolve(x)
-		}
-	}
-	p.inRhs = old
-	return list
-}
-
-func (p *parser) parseRhsList() []ast.Expr {
-	old := p.inRhs
-	p.inRhs = true
-	list := p.parseExprList(false)
-	p.inRhs = old
-	return list
-}
-
-// ----------------------------------------------------------------------------
-// Types
-
-func (p *parser) parseType() ast.Expr {
-	if p.trace {
-		defer un(trace(p, "Type"))
-	}
-
-	typ := p.tryType()
-
-	if typ == nil {
-		pos := p.pos
-		p.errorExpected(pos, "type")
-		p.next() // make progress
-		return &ast.BadExpr{From: pos, To: p.pos}
-	}
-
-	return typ
-}
-
-// If the result is an identifier, it is not resolved.
-func (p *parser) parseTypeName() ast.Expr {
-	if p.trace {
-		defer un(trace(p, "TypeName"))
-	}
-
-	ident := p.parseIdent()
-	// don't resolve ident yet - it may be a parameter or field name
-
-	if p.tok == token.PERIOD {
-		// ident is a package name
-		p.next()
-		p.resolve(ident)
-		sel := p.parseIdent()
-		return &ast.SelectorExpr{X: ident, Sel: sel}
-	}
-
-	return ident
-}
-
-func (p *parser) parseArrayType() ast.Expr {
-	if p.trace {
-		defer un(trace(p, "ArrayType"))
-	}
-
-	lbrack := p.expect(token.LBRACK)
-	var len ast.Expr
-	// always permit ellipsis for more fault-tolerant parsing
-	if p.tok == token.ELLIPSIS {
-		len = &ast.Ellipsis{Ellipsis: p.pos}
-		p.next()
-	} else if p.tok != token.RBRACK {
-		len = p.parseRhs()
-	}
-	p.expect(token.RBRACK)
-	elt := p.parseType()
-
-	return &ast.ArrayType{Lbrack: lbrack, Len: len, Elt: elt}
-}
-
-func (p *parser) makeIdentList(list []ast.Expr) []*ast.Ident {
-	idents := make([]*ast.Ident, len(list))
-	for i, x := range list {
-		ident, isIdent := x.(*ast.Ident)
-		if !isIdent {
-			if _, isBad := x.(*ast.BadExpr); !isBad {
-				// only report error if it's a new one
-				p.errorExpected(x.Pos(), "identifier")
-			}
-			ident = &ast.Ident{NamePos: x.Pos(), Name: "_"}
-		}
-		idents[i] = ident
-	}
-	return idents
-}
-
-func (p *parser) parseFieldDecl(scope *ast.Scope) *ast.Field {
-	if p.trace {
-		defer un(trace(p, "FieldDecl"))
-	}
-
-	doc := p.leadComment
-
-	// FieldDecl
-	list, typ := p.parseVarList(false)
-
-	// Tag
-	var tag *ast.BasicLit
-	if p.tok == token.STRING {
-		tag = &ast.BasicLit{ValuePos: p.pos, Kind: p.tok, Value: p.lit}
-		p.next()
-	}
-
-	// analyze case
-	var idents []*ast.Ident
-	if typ != nil {
-		// IdentifierList Type
-		idents = p.makeIdentList(list)
-	} else {
-		// ["*"] TypeName (AnonymousField)
-		typ = list[0] // we always have at least one element
-		if n := len(list); n > 1 || !isTypeName(deref(typ)) {
-			pos := typ.Pos()
-			p.errorExpected(pos, "anonymous field")
-			typ = &ast.BadExpr{From: pos, To: p.safePos(list[n-1].End())}
-		}
-	}
-
-	p.expectSemi() // call before accessing p.linecomment
-
-	field := &ast.Field{Doc: doc, Names: idents, Type: typ, Tag: tag, Comment: p.lineComment}
-	p.declare(field, nil, scope, ast.Var, idents...)
-	p.resolve(typ)
-
-	return field
-}
-
-func (p *parser) parseStructType() *ast.StructType {
-	if p.trace {
-		defer un(trace(p, "StructType"))
-	}
-
-	pos := p.expect(token.STRUCT)
-	lbrace := p.expect(token.LBRACE)
-	scope := ast.NewScope(nil) // struct scope
-	var list []*ast.Field
-	for p.tok == token.IDENT || p.tok == token.MUL || p.tok == token.LPAREN {
-		// a field declaration cannot start with a '(' but we accept
-		// it here for more robust parsing and better error messages
-		// (parseFieldDecl will check and complain if necessary)
-		list = append(list, p.parseFieldDecl(scope))
-	}
-	rbrace := p.expect(token.RBRACE)
-
-	return &ast.StructType{
-		Struct: pos,
-		Fields: &ast.FieldList{
-			Opening: lbrace,
-			List:    list,
-			Closing: rbrace,
-		},
-	}
-}
-
-func (p *parser) parsePointerType() *ast.StarExpr {
-	if p.trace {
-		defer un(trace(p, "PointerType"))
-	}
-
-	star := p.expect(token.MUL)
-	base := p.parseType()
-
-	return &ast.StarExpr{Star: star, X: base}
-}
-
-// If the result is an identifier, it is not resolved.
-func (p *parser) tryVarType(isParam bool) ast.Expr {
-	if isParam && p.tok == token.ELLIPSIS {
-		pos := p.pos
-		p.next()
-		typ := p.tryIdentOrType() // don't use parseType so we can provide better error message
-		if typ != nil {
-			p.resolve(typ)
-		} else {
-			p.error(pos, "'...' parameter is missing type")
-			typ = &ast.BadExpr{From: pos, To: p.pos}
-		}
-		return &ast.Ellipsis{Ellipsis: pos, Elt: typ}
-	}
-	return p.tryIdentOrType()
-}
-
-// If the result is an identifier, it is not resolved.
-func (p *parser) parseVarType(isParam bool) ast.Expr {
-	typ := p.tryVarType(isParam)
-	if typ == nil {
-		pos := p.pos
-		p.errorExpected(pos, "type")
-		p.next() // make progress
-		typ = &ast.BadExpr{From: pos, To: p.pos}
-	}
-	return typ
-}
-
-// If any of the results are identifiers, they are not resolved.
-func (p *parser) parseVarList(isParam bool) (list []ast.Expr, typ ast.Expr) {
-	if p.trace {
-		defer un(trace(p, "VarList"))
-	}
-
-	// a list of identifiers looks like a list of type names
-	//
-	// parse/tryVarType accepts any type (including parenthesized
-	// ones) even though the syntax does not permit them here: we
-	// accept them all for more robust parsing and complain later
-	for typ := p.parseVarType(isParam); typ != nil; {
-		list = append(list, typ)
-		if p.tok != token.COMMA {
-			break
-		}
-		p.next()
-		typ = p.tryVarType(isParam) // maybe nil as in: func f(int,) {}
-	}
-
-	// if we had a list of identifiers, it must be followed by a type
-	typ = p.tryVarType(isParam)
-
-	return
-}
-
-func (p *parser) parseParameterList(scope *ast.Scope, ellipsisOk bool) (params []*ast.Field) {
-	if p.trace {
-		defer un(trace(p, "ParameterList"))
-	}
-
-	// ParameterDecl
-	list, typ := p.parseVarList(ellipsisOk)
-
-	// analyze case
-	if typ != nil {
-		// IdentifierList Type
-		idents := p.makeIdentList(list)
-		field := &ast.Field{Names: idents, Type: typ}
-		params = append(params, field)
-		// Go spec: The scope of an identifier denoting a function
-		// parameter or result variable is the function body.
-		p.declare(field, nil, scope, ast.Var, idents...)
-		p.resolve(typ)
-		if p.tok == token.COMMA {
-			p.next()
-		}
-		for p.tok != token.RPAREN && p.tok != token.EOF {
-			idents := p.parseIdentList()
-			typ := p.parseVarType(ellipsisOk)
-			field := &ast.Field{Names: idents, Type: typ}
-			params = append(params, field)
-			// Go spec: The scope of an identifier denoting a function
-			// parameter or result variable is the function body.
-			p.declare(field, nil, scope, ast.Var, idents...)
-			p.resolve(typ)
-			if !p.atComma("parameter list") {
-				break
-			}
-			p.next()
-		}
-	} else {
-		// Type { "," Type } (anonymous parameters)
-		params = make([]*ast.Field, len(list))
-		for i, typ := range list {
-			p.resolve(typ)
-			params[i] = &ast.Field{Type: typ}
-		}
-	}
-
-	return
-}
-
-func (p *parser) parseParameters(scope *ast.Scope, ellipsisOk bool) *ast.FieldList {
-	if p.trace {
-		defer un(trace(p, "Parameters"))
-	}
-
-	var params []*ast.Field
-	lparen := p.expect(token.LPAREN)
-	if p.tok != token.RPAREN {
-		params = p.parseParameterList(scope, ellipsisOk)
-	}
-	rparen := p.expect(token.RPAREN)
-
-	return &ast.FieldList{Opening: lparen, List: params, Closing: rparen}
-}
-
-func (p *parser) parseResult(scope *ast.Scope) *ast.FieldList {
-	if p.trace {
-		defer un(trace(p, "Result"))
-	}
-
-	if p.tok == token.LPAREN {
-		return p.parseParameters(scope, false)
-	}
-
-	typ := p.tryType()
-	if typ != nil {
-		list := make([]*ast.Field, 1)
-		list[0] = &ast.Field{Type: typ}
-		return &ast.FieldList{List: list}
-	}
-
-	return nil
-}
-
-func (p *parser) parseSignature(scope *ast.Scope) (params, results *ast.FieldList) {
-	if p.trace {
-		defer un(trace(p, "Signature"))
-	}
-
-	params = p.parseParameters(scope, true)
-	results = p.parseResult(scope)
-
-	return
-}
-
-func (p *parser) parseFuncType() (*ast.FuncType, *ast.Scope) {
-	if p.trace {
-		defer un(trace(p, "FuncType"))
-	}
-
-	pos := p.expect(token.FUNC)
-	scope := ast.NewScope(p.topScope) // function scope
-	params, results := p.parseSignature(scope)
-
-	return &ast.FuncType{Func: pos, Params: params, Results: results}, scope
-}
-
-func (p *parser) parseMethodSpec(scope *ast.Scope) *ast.Field {
-	if p.trace {
-		defer un(trace(p, "MethodSpec"))
-	}
-
-	doc := p.leadComment
-	var idents []*ast.Ident
-	var typ ast.Expr
-	x := p.parseTypeName()
-	if ident, isIdent := x.(*ast.Ident); isIdent && p.tok == token.LPAREN {
-		// method
-		idents = []*ast.Ident{ident}
-		scope := ast.NewScope(nil) // method scope
-		params, results := p.parseSignature(scope)
-		typ = &ast.FuncType{Func: token.NoPos, Params: params, Results: results}
-	} else {
-		// embedded interface
-		typ = x
-		p.resolve(typ)
-	}
-	p.expectSemi() // call before accessing p.linecomment
-
-	spec := &ast.Field{Doc: doc, Names: idents, Type: typ, Comment: p.lineComment}
-	p.declare(spec, nil, scope, ast.Fun, idents...)
-
-	return spec
-}
-
-func (p *parser) parseInterfaceType() *ast.InterfaceType {
-	if p.trace {
-		defer un(trace(p, "InterfaceType"))
-	}
-
-	pos := p.expect(token.INTERFACE)
-	lbrace := p.expect(token.LBRACE)
-	scope := ast.NewScope(nil) // interface scope
-	var list []*ast.Field
-	for p.tok == token.IDENT {
-		list = append(list, p.parseMethodSpec(scope))
-	}
-	rbrace := p.expect(token.RBRACE)
-
-	return &ast.InterfaceType{
-		Interface: pos,
-		Methods: &ast.FieldList{
-			Opening: lbrace,
-			List:    list,
-			Closing: rbrace,
-		},
-	}
-}
-
-func (p *parser) parseMapType() *ast.MapType {
-	if p.trace {
-		defer un(trace(p, "MapType"))
-	}
-
-	pos := p.expect(token.MAP)
-	p.expect(token.LBRACK)
-	key := p.parseType()
-	p.expect(token.RBRACK)
-	value := p.parseType()
-
-	return &ast.MapType{Map: pos, Key: key, Value: value}
-}
-
-func (p *parser) parseChanType() *ast.ChanType {
-	if p.trace {
-		defer un(trace(p, "ChanType"))
-	}
-
-	pos := p.pos
-	dir := ast.SEND | ast.RECV
-	var arrow token.Pos
-	if p.tok == token.CHAN {
-		p.next()
-		if p.tok == token.ARROW {
-			arrow = p.pos
-			p.next()
-			dir = ast.SEND
-		}
-	} else {
-		arrow = p.expect(token.ARROW)
-		p.expect(token.CHAN)
-		dir = ast.RECV
-	}
-	value := p.parseType()
-
-	return &ast.ChanType{Begin: pos, Arrow: arrow, Dir: dir, Value: value}
-}
-
-// If the result is an identifier, it is not resolved.
-func (p *parser) tryIdentOrType() ast.Expr {
-	switch p.tok {
-	case token.IDENT:
-		return p.parseTypeName()
-	case token.LBRACK:
-		return p.parseArrayType()
-	case token.STRUCT:
-		return p.parseStructType()
-	case token.MUL:
-		return p.parsePointerType()
-	case token.FUNC:
-		typ, _ := p.parseFuncType()
-		return typ
-	case token.INTERFACE:
-		return p.parseInterfaceType()
-	case token.MAP:
-		return p.parseMapType()
-	case token.CHAN, token.ARROW:
-		return p.parseChanType()
-	case token.LPAREN:
-		lparen := p.pos
-		p.next()
-		typ := p.parseType()
-		rparen := p.expect(token.RPAREN)
-		return &ast.ParenExpr{Lparen: lparen, X: typ, Rparen: rparen}
-	}
-
-	// no type found
-	return nil
-}
-
-func (p *parser) tryType() ast.Expr {
-	typ := p.tryIdentOrType()
-	if typ != nil {
-		p.resolve(typ)
-	}
-	return typ
-}
-
-// ----------------------------------------------------------------------------
-// Blocks
-
-func (p *parser) parseStmtList() (list []ast.Stmt) {
-	if p.trace {
-		defer un(trace(p, "StatementList"))
-	}
-
-	for p.tok != token.CASE && p.tok != token.DEFAULT && p.tok != token.RBRACE && p.tok != token.EOF {
-		list = append(list, p.parseStmt())
-	}
-
-	return
-}
-
-func (p *parser) parseBody(scope *ast.Scope) *ast.BlockStmt {
-	if p.trace {
-		defer un(trace(p, "Body"))
-	}
-
-	lbrace := p.expect(token.LBRACE)
-	p.topScope = scope // open function scope
-	p.openLabelScope()
-	list := p.parseStmtList()
-	p.closeLabelScope()
-	p.closeScope()
-	rbrace := p.expect(token.RBRACE)
-
-	return &ast.BlockStmt{Lbrace: lbrace, List: list, Rbrace: rbrace}
-}
-
-func (p *parser) parseBlockStmt() *ast.BlockStmt {
-	if p.trace {
-		defer un(trace(p, "BlockStmt"))
-	}
-
-	lbrace := p.expect(token.LBRACE)
-	p.openScope()
-	list := p.parseStmtList()
-	p.closeScope()
-	rbrace := p.expect(token.RBRACE)
-
-	return &ast.BlockStmt{Lbrace: lbrace, List: list, Rbrace: rbrace}
-}
-
-// ----------------------------------------------------------------------------
-// Expressions
-
-func (p *parser) parseFuncTypeOrLit() ast.Expr {
-	if p.trace {
-		defer un(trace(p, "FuncTypeOrLit"))
-	}
-
-	typ, scope := p.parseFuncType()
-	if p.tok != token.LBRACE {
-		// function type only
-		return typ
-	}
-
-	p.exprLev++
-	body := p.parseBody(scope)
-	p.exprLev--
-
-	return &ast.FuncLit{Type: typ, Body: body}
-}
-
-// parseOperand may return an expression or a raw type (incl. array
-// types of the form [...]T. Callers must verify the result.
-// If lhs is set and the result is an identifier, it is not resolved.
-//
-func (p *parser) parseOperand(lhs bool) ast.Expr {
-	if p.trace {
-		defer un(trace(p, "Operand"))
-	}
-
-	switch p.tok {
-	case token.IDENT:
-		x := p.parseIdent()
-		if !lhs {
-			p.resolve(x)
-		}
-		return x
-
-	case token.INT, token.FLOAT, token.IMAG, token.CHAR, token.STRING:
-		x := &ast.BasicLit{ValuePos: p.pos, Kind: p.tok, Value: p.lit}
-		p.next()
-		return x
-
-	case token.LPAREN:
-		lparen := p.pos
-		p.next()
-		p.exprLev++
-		x := p.parseRhsOrType() // types may be parenthesized: (some type)
-		p.exprLev--
-		rparen := p.expect(token.RPAREN)
-		return &ast.ParenExpr{Lparen: lparen, X: x, Rparen: rparen}
-
-	case token.FUNC:
-		return p.parseFuncTypeOrLit()
-	}
-
-	if typ := p.tryIdentOrType(); typ != nil {
-		// could be type for composite literal or conversion
-		_, isIdent := typ.(*ast.Ident)
-		assert(!isIdent, "type cannot be identifier")
-		return typ
-	}
-
-	// we have an error
-	pos := p.pos
-	p.errorExpected(pos, "operand")
-	syncStmt(p)
-	return &ast.BadExpr{From: pos, To: p.pos}
-}
-
-func (p *parser) parseSelector(x ast.Expr) ast.Expr {
-	if p.trace {
-		defer un(trace(p, "Selector"))
-	}
-
-	sel := p.parseIdent()
-
-	return &ast.SelectorExpr{X: x, Sel: sel}
-}
-
-func (p *parser) parseTypeAssertion(x ast.Expr) ast.Expr {
-	if p.trace {
-		defer un(trace(p, "TypeAssertion"))
-	}
-
-	lparen := p.expect(token.LPAREN)
-	var typ ast.Expr
-	if p.tok == token.TYPE {
-		// type switch: typ == nil
-		p.next()
-	} else {
-		typ = p.parseType()
-	}
-	rparen := p.expect(token.RPAREN)
-
-	return &ast.TypeAssertExpr{X: x, Type: typ, Lparen: lparen, Rparen: rparen}
-}
-
-func (p *parser) parseIndexOrSlice(x ast.Expr) ast.Expr {
-	if p.trace {
-		defer un(trace(p, "IndexOrSlice"))
-	}
-
-	const N = 3 // change the 3 to 2 to disable 3-index slices
-	lbrack := p.expect(token.LBRACK)
-	p.exprLev++
-	var index [N]ast.Expr
-	var colons [N - 1]token.Pos
-	if p.tok != token.COLON {
-		index[0] = p.parseRhs()
-	}
-	ncolons := 0
-	for p.tok == token.COLON && ncolons < len(colons) {
-		colons[ncolons] = p.pos
-		ncolons++
-		p.next()
-		if p.tok != token.COLON && p.tok != token.RBRACK && p.tok != token.EOF {
-			index[ncolons] = p.parseRhs()
-		}
-	}
-	p.exprLev--
-	rbrack := p.expect(token.RBRACK)
-
-	if ncolons > 0 {
-		// slice expression
-		slice3 := false
-		if ncolons == 2 {
-			slice3 = true
-			// Check presence of 2nd and 3rd index here rather than during type-checking
-			// to prevent erroneous programs from passing through gofmt (was issue 7305).
-			if index[1] == nil {
-				p.error(colons[0], "2nd index required in 3-index slice")
-				index[1] = &ast.BadExpr{From: colons[0] + 1, To: colons[1]}
-			}
-			if index[2] == nil {
-				p.error(colons[1], "3rd index required in 3-index slice")
-				index[2] = &ast.BadExpr{From: colons[1] + 1, To: rbrack}
-			}
-		}
-		return &ast.SliceExpr{X: x, Lbrack: lbrack, Low: index[0], High: index[1], Max: index[2], Slice3: slice3, Rbrack: rbrack}
-	}
-
-	return &ast.IndexExpr{X: x, Lbrack: lbrack, Index: index[0], Rbrack: rbrack}
-}
-
-func (p *parser) parseCallOrConversion(fun ast.Expr) *ast.CallExpr {
-	if p.trace {
-		defer un(trace(p, "CallOrConversion"))
-	}
-
-	lparen := p.expect(token.LPAREN)
-	p.exprLev++
-	var list []ast.Expr
-	var ellipsis token.Pos
-	for p.tok != token.RPAREN && p.tok != token.EOF && !ellipsis.IsValid() {
-		list = append(list, p.parseRhsOrType()) // builtins may expect a type: make(some type, ...)
-		if p.tok == token.ELLIPSIS {
-			ellipsis = p.pos
-			p.next()
-		}
-		if !p.atComma("argument list") {
-			break
-		}
-		p.next()
-	}
-	p.exprLev--
-	rparen := p.expectClosing(token.RPAREN, "argument list")
-
-	return &ast.CallExpr{Fun: fun, Lparen: lparen, Args: list, Ellipsis: ellipsis, Rparen: rparen}
-}
-
-func (p *parser) parseElement(keyOk bool) ast.Expr {
-	if p.trace {
-		defer un(trace(p, "Element"))
-	}
-
-	if p.tok == token.LBRACE {
-		return p.parseLiteralValue(nil)
-	}
-
-	// Because the parser doesn't know the composite literal type, it cannot
-	// know if a key that's an identifier is a struct field name or a name
-	// denoting a value. The former is not resolved by the parser or the
-	// resolver.
-	//
-	// Instead, _try_ to resolve such a key if possible. If it resolves,
-	// it a) has correctly resolved, or b) incorrectly resolved because
-	// the key is a struct field with a name matching another identifier.
-	// In the former case we are done, and in the latter case we don't
-	// care because the type checker will do a separate field lookup.
-	//
-	// If the key does not resolve, it a) must be defined at the top
-	// level in another file of the same package, the universe scope, or be
-	// undeclared; or b) it is a struct field. In the former case, the type
-	// checker can do a top-level lookup, and in the latter case it will do
-	// a separate field lookup.
-	x := p.checkExpr(p.parseExpr(keyOk))
-	if keyOk {
-		if p.tok == token.COLON {
-			colon := p.pos
-			p.next()
-			// Try to resolve the key but don't collect it
-			// as unresolved identifier if it fails so that
-			// we don't get (possibly false) errors about
-			// undeclared names.
-			p.tryResolve(x, false)
-			return &ast.KeyValueExpr{Key: x, Colon: colon, Value: p.parseElement(false)}
-		}
-		p.resolve(x) // not a key
-	}
-
-	return x
-}
-
-func (p *parser) parseElementList() (list []ast.Expr) {
-	if p.trace {
-		defer un(trace(p, "ElementList"))
-	}
-
-	for p.tok != token.RBRACE && p.tok != token.EOF {
-		list = append(list, p.parseElement(true))
-		if !p.atComma("composite literal") {
-			break
-		}
-		p.next()
-	}
-
-	return
-}
-
-func (p *parser) parseLiteralValue(typ ast.Expr) ast.Expr {
-	if p.trace {
-		defer un(trace(p, "LiteralValue"))
-	}
-
-	lbrace := p.expect(token.LBRACE)
-	var elts []ast.Expr
-	p.exprLev++
-	if p.tok != token.RBRACE {
-		elts = p.parseElementList()
-	}
-	p.exprLev--
-	rbrace := p.expectClosing(token.RBRACE, "composite literal")
-	return &ast.CompositeLit{Type: typ, Lbrace: lbrace, Elts: elts, Rbrace: rbrace}
-}
-
-// checkExpr checks that x is an expression (and not a type).
-func (p *parser) checkExpr(x ast.Expr) ast.Expr {
-	switch unparen(x).(type) {
-	case *ast.BadExpr:
-	case *ast.Ident:
-	case *ast.BasicLit:
-	case *ast.FuncLit:
-	case *ast.CompositeLit:
-	case *ast.ParenExpr:
-		panic("unreachable")
-	case *ast.SelectorExpr:
-	case *ast.IndexExpr:
-	case *ast.SliceExpr:
-	case *ast.TypeAssertExpr:
-		// If t.Type == nil we have a type assertion of the form
-		// y.(type), which is only allowed in type switch expressions.
-		// It's hard to exclude those but for the case where we are in
-		// a type switch. Instead be lenient and test this in the type
-		// checker.
-	case *ast.CallExpr:
-	case *ast.StarExpr:
-	case *ast.UnaryExpr:
-	case *ast.BinaryExpr:
-	default:
-		// all other nodes are not proper expressions
-		p.errorExpected(x.Pos(), "expression")
-		x = &ast.BadExpr{From: x.Pos(), To: p.safePos(x.End())}
-	}
-	return x
-}
-
-// isTypeName returns true iff x is a (qualified) TypeName.
-func isTypeName(x ast.Expr) bool {
-	switch t := x.(type) {
-	case *ast.BadExpr:
-	case *ast.Ident:
-	case *ast.SelectorExpr:
-		_, isIdent := t.X.(*ast.Ident)
-		return isIdent
-	default:
-		return false // all other nodes are not type names
-	}
-	return true
-}
-
-// isLiteralType returns true iff x is a legal composite literal type.
-func isLiteralType(x ast.Expr) bool {
-	switch t := x.(type) {
-	case *ast.BadExpr:
-	case *ast.Ident:
-	case *ast.SelectorExpr:
-		_, isIdent := t.X.(*ast.Ident)
-		return isIdent
-	case *ast.ArrayType:
-	case *ast.StructType:
-	case *ast.MapType:
-	default:
-		return false // all other nodes are not legal composite literal types
-	}
-	return true
-}
-
-// If x is of the form *T, deref returns T, otherwise it returns x.
-func deref(x ast.Expr) ast.Expr {
-	if p, isPtr := x.(*ast.StarExpr); isPtr {
-		x = p.X
-	}
-	return x
-}
-
-// If x is of the form (T), unparen returns unparen(T), otherwise it returns x.
-func unparen(x ast.Expr) ast.Expr {
-	if p, isParen := x.(*ast.ParenExpr); isParen {
-		x = unparen(p.X)
-	}
-	return x
-}
-
-// checkExprOrType checks that x is an expression or a type
-// (and not a raw type such as [...]T).
-//
-func (p *parser) checkExprOrType(x ast.Expr) ast.Expr {
-	switch t := unparen(x).(type) {
-	case *ast.ParenExpr:
-		panic("unreachable")
-	case *ast.UnaryExpr:
-	case *ast.ArrayType:
-		if len, isEllipsis := t.Len.(*ast.Ellipsis); isEllipsis {
-			p.error(len.Pos(), "expected array length, found '...'")
-			x = &ast.BadExpr{From: x.Pos(), To: p.safePos(x.End())}
-		}
-	}
-
-	// all other nodes are expressions or types
-	return x
-}
-
-// If lhs is set and the result is an identifier, it is not resolved.
-func (p *parser) parsePrimaryExpr(lhs bool) ast.Expr {
-	if p.trace {
-		defer un(trace(p, "PrimaryExpr"))
-	}
-
-	x := p.parseOperand(lhs)
-L:
-	for {
-		switch p.tok {
-		case token.PERIOD:
-			p.next()
-			if lhs {
-				p.resolve(x)
-			}
-			switch p.tok {
-			case token.IDENT:
-				x = p.parseSelector(p.checkExprOrType(x))
-			case token.LPAREN:
-				x = p.parseTypeAssertion(p.checkExpr(x))
-			default:
-				pos := p.pos
-				p.errorExpected(pos, "selector or type assertion")
-				p.next() // make progress
-				x = &ast.BadExpr{From: pos, To: p.pos}
-			}
-		case token.LBRACK:
-			if lhs {
-				p.resolve(x)
-			}
-			x = p.parseIndexOrSlice(p.checkExpr(x))
-		case token.LPAREN:
-			if lhs {
-				p.resolve(x)
-			}
-			x = p.parseCallOrConversion(p.checkExprOrType(x))
-		case token.LBRACE:
-			if isLiteralType(x) && (p.exprLev >= 0 || !isTypeName(x)) {
-				if lhs {
-					p.resolve(x)
-				}
-				x = p.parseLiteralValue(x)
-			} else {
-				break L
-			}
-		default:
-			break L
-		}
-		lhs = false // no need to try to resolve again
-	}
-
-	return x
-}
-
-// If lhs is set and the result is an identifier, it is not resolved.
-func (p *parser) parseUnaryExpr(lhs bool) ast.Expr {
-	if p.trace {
-		defer un(trace(p, "UnaryExpr"))
-	}
-
-	switch p.tok {
-	case token.ADD, token.SUB, token.NOT, token.XOR, token.AND:
-		pos, op := p.pos, p.tok
-		p.next()
-		x := p.parseUnaryExpr(false)
-		return &ast.UnaryExpr{OpPos: pos, Op: op, X: p.checkExpr(x)}
-
-	case token.ARROW:
-		// channel type or receive expression
-		arrow := p.pos
-		p.next()
-
-		// If the next token is token.CHAN we still don't know if it
-		// is a channel type or a receive operation - we only know
-		// once we have found the end of the unary expression. There
-		// are two cases:
-		//
-		//   <- type  => (<-type) must be channel type
-		//   <- expr  => <-(expr) is a receive from an expression
-		//
-		// In the first case, the arrow must be re-associated with
-		// the channel type parsed already:
-		//
-		//   <- (chan type)    =>  (<-chan type)
-		//   <- (chan<- type)  =>  (<-chan (<-type))
-
-		x := p.parseUnaryExpr(false)
-
-		// determine which case we have
-		if typ, ok := x.(*ast.ChanType); ok {
-			// (<-type)
-
-			// re-associate position info and <-
-			dir := ast.SEND
-			for ok && dir == ast.SEND {
-				if typ.Dir == ast.RECV {
-					// error: (<-type) is (<-(<-chan T))
-					p.errorExpected(typ.Arrow, "'chan'")
-				}
-				arrow, typ.Begin, typ.Arrow = typ.Arrow, arrow, arrow
-				dir, typ.Dir = typ.Dir, ast.RECV
-				typ, ok = typ.Value.(*ast.ChanType)
-			}
-			if dir == ast.SEND {
-				p.errorExpected(arrow, "channel type")
-			}
-
-			return x
-		}
-
-		// <-(expr)
-		return &ast.UnaryExpr{OpPos: arrow, Op: token.ARROW, X: p.checkExpr(x)}
-
-	case token.MUL:
-		// pointer type or unary "*" expression
-		pos := p.pos
-		p.next()
-		x := p.parseUnaryExpr(false)
-		return &ast.StarExpr{Star: pos, X: p.checkExprOrType(x)}
-	}
-
-	return p.parsePrimaryExpr(lhs)
-}
-
-func (p *parser) tokPrec() (token.Token, int) {
-	tok := p.tok
-	if p.inRhs && tok == token.ASSIGN {
-		tok = token.EQL
-	}
-	return tok, tok.Precedence()
-}
-
-// If lhs is set and the result is an identifier, it is not resolved.
-func (p *parser) parseBinaryExpr(lhs bool, prec1 int) ast.Expr {
-	if p.trace {
-		defer un(trace(p, "BinaryExpr"))
-	}
-
-	x := p.parseUnaryExpr(lhs)
-	for _, prec := p.tokPrec(); prec >= prec1; prec-- {
-		for {
-			op, oprec := p.tokPrec()
-			if oprec != prec {
-				break
-			}
-			pos := p.expect(op)
-			if lhs {
-				p.resolve(x)
-				lhs = false
-			}
-			y := p.parseBinaryExpr(false, prec+1)
-			x = &ast.BinaryExpr{X: p.checkExpr(x), OpPos: pos, Op: op, Y: p.checkExpr(y)}
-		}
-	}
-
-	return x
-}
-
-// If lhs is set and the result is an identifier, it is not resolved.
-// The result may be a type or even a raw type ([...]int). Callers must
-// check the result (using checkExpr or checkExprOrType), depending on
-// context.
-func (p *parser) parseExpr(lhs bool) ast.Expr {
-	if p.trace {
-		defer un(trace(p, "Expression"))
-	}
-
-	return p.parseBinaryExpr(lhs, token.LowestPrec+1)
-}
-
-func (p *parser) parseRhs() ast.Expr {
-	old := p.inRhs
-	p.inRhs = true
-	x := p.checkExpr(p.parseExpr(false))
-	p.inRhs = old
-	return x
-}
-
-func (p *parser) parseRhsOrType() ast.Expr {
-	old := p.inRhs
-	p.inRhs = true
-	x := p.checkExprOrType(p.parseExpr(false))
-	p.inRhs = old
-	return x
-}
-
-// ----------------------------------------------------------------------------
-// Statements
-
-// Parsing modes for parseSimpleStmt.
-const (
-	basic = iota
-	labelOk
-	rangeOk
-)
-
-// parseSimpleStmt returns true as 2nd result if it parsed the assignment
-// of a range clause (with mode == rangeOk). The returned statement is an
-// assignment with a right-hand side that is a single unary expression of
-// the form "range x". No guarantees are given for the left-hand side.
-func (p *parser) parseSimpleStmt(mode int) (ast.Stmt, bool) {
-	if p.trace {
-		defer un(trace(p, "SimpleStmt"))
-	}
-
-	x := p.parseLhsList()
-
-	switch p.tok {
-	case
-		token.DEFINE, token.ASSIGN, token.ADD_ASSIGN,
-		token.SUB_ASSIGN, token.MUL_ASSIGN, token.QUO_ASSIGN,
-		token.REM_ASSIGN, token.AND_ASSIGN, token.OR_ASSIGN,
-		token.XOR_ASSIGN, token.SHL_ASSIGN, token.SHR_ASSIGN, token.AND_NOT_ASSIGN:
-		// assignment statement, possibly part of a range clause
-		pos, tok := p.pos, p.tok
-		p.next()
-		var y []ast.Expr
-		isRange := false
-		if mode == rangeOk && p.tok == token.RANGE && (tok == token.DEFINE || tok == token.ASSIGN) {
-			pos := p.pos
-			p.next()
-			y = []ast.Expr{&ast.UnaryExpr{OpPos: pos, Op: token.RANGE, X: p.parseRhs()}}
-			isRange = true
-		} else {
-			y = p.parseRhsList()
-		}
-		as := &ast.AssignStmt{Lhs: x, TokPos: pos, Tok: tok, Rhs: y}
-		if tok == token.DEFINE {
-			p.shortVarDecl(as, x)
-		}
-		return as, isRange
-	}
-
-	if len(x) > 1 {
-		p.errorExpected(x[0].Pos(), "1 expression")
-		// continue with first expression
-	}
-
-	switch p.tok {
-	case token.COLON:
-		// labeled statement
-		colon := p.pos
-		p.next()
-		if label, isIdent := x[0].(*ast.Ident); mode == labelOk && isIdent {
-			// Go spec: The scope of a label is the body of the function
-			// in which it is declared and excludes the body of any nested
-			// function.
-			stmt := &ast.LabeledStmt{Label: label, Colon: colon, Stmt: p.parseStmt()}
-			p.declare(stmt, nil, p.labelScope, ast.Lbl, label)
-			return stmt, false
-		}
-		// The label declaration typically starts at x[0].Pos(), but the label
-		// declaration may be erroneous due to a token after that position (and
-		// before the ':'). If SpuriousErrors is not set, the (only) error re-
-		// ported for the line is the illegal label error instead of the token
-		// before the ':' that caused the problem. Thus, use the (latest) colon
-		// position for error reporting.
-		p.error(colon, "illegal label declaration")
-		return &ast.BadStmt{From: x[0].Pos(), To: colon + 1}, false
-
-	case token.ARROW:
-		// send statement
-		arrow := p.pos
-		p.next()
-		y := p.parseRhs()
-		return &ast.SendStmt{Chan: x[0], Arrow: arrow, Value: y}, false
-
-	case token.INC, token.DEC:
-		// increment or decrement
-		s := &ast.IncDecStmt{X: x[0], TokPos: p.pos, Tok: p.tok}
-		p.next()
-		return s, false
-	}
-
-	// expression
-	return &ast.ExprStmt{X: x[0]}, false
-}
-
-func (p *parser) parseCallExpr(callType string) *ast.CallExpr {
-	x := p.parseRhsOrType() // could be a conversion: (some type)(x)
-	if call, isCall := x.(*ast.CallExpr); isCall {
-		return call
-	}
-	if _, isBad := x.(*ast.BadExpr); !isBad {
-		// only report error if it's a new one
-		p.error(p.safePos(x.End()), fmt.Sprintf("function must be invoked in %s statement", callType))
-	}
-	return nil
-}
-
-func (p *parser) parseGoStmt() ast.Stmt {
-	if p.trace {
-		defer un(trace(p, "GoStmt"))
-	}
-
-	pos := p.expect(token.GO)
-	call := p.parseCallExpr("go")
-	p.expectSemi()
-	if call == nil {
-		return &ast.BadStmt{From: pos, To: pos + 2} // len("go")
-	}
-
-	return &ast.GoStmt{Go: pos, Call: call}
-}
-
-func (p *parser) parseDeferStmt() ast.Stmt {
-	if p.trace {
-		defer un(trace(p, "DeferStmt"))
-	}
-
-	pos := p.expect(token.DEFER)
-	call := p.parseCallExpr("defer")
-	p.expectSemi()
-	if call == nil {
-		return &ast.BadStmt{From: pos, To: pos + 5} // len("defer")
-	}
-
-	return &ast.DeferStmt{Defer: pos, Call: call}
-}
-
-func (p *parser) parseReturnStmt() *ast.ReturnStmt {
-	if p.trace {
-		defer un(trace(p, "ReturnStmt"))
-	}
-
-	pos := p.pos
-	p.expect(token.RETURN)
-	var x []ast.Expr
-	if p.tok != token.SEMICOLON && p.tok != token.RBRACE {
-		x = p.parseRhsList()
-	}
-	p.expectSemi()
-
-	return &ast.ReturnStmt{Return: pos, Results: x}
-}
-
-func (p *parser) parseBranchStmt(tok token.Token) *ast.BranchStmt {
-	if p.trace {
-		defer un(trace(p, "BranchStmt"))
-	}
-
-	pos := p.expect(tok)
-	var label *ast.Ident
-	if tok != token.FALLTHROUGH && p.tok == token.IDENT {
-		label = p.parseIdent()
-		// add to list of unresolved targets
-		n := len(p.targetStack) - 1
-		p.targetStack[n] = append(p.targetStack[n], label)
-	}
-	p.expectSemi()
-
-	return &ast.BranchStmt{TokPos: pos, Tok: tok, Label: label}
-}
-
-func (p *parser) makeExpr(s ast.Stmt, kind string) ast.Expr {
-	if s == nil {
-		return nil
-	}
-	if es, isExpr := s.(*ast.ExprStmt); isExpr {
-		return p.checkExpr(es.X)
-	}
-	p.error(s.Pos(), fmt.Sprintf("expected %s, found simple statement (missing parentheses around composite literal?)", kind))
-	return &ast.BadExpr{From: s.Pos(), To: p.safePos(s.End())}
-}
-
-func (p *parser) parseIfStmt() *ast.IfStmt {
-	if p.trace {
-		defer un(trace(p, "IfStmt"))
-	}
-
-	pos := p.expect(token.IF)
-	p.openScope()
-	defer p.closeScope()
-
-	var s ast.Stmt
-	var x ast.Expr
-	{
-		prevLev := p.exprLev
-		p.exprLev = -1
-		if p.tok == token.SEMICOLON {
-			p.next()
-			x = p.parseRhs()
-		} else {
-			s, _ = p.parseSimpleStmt(basic)
-			if p.tok == token.SEMICOLON {
-				p.next()
-				x = p.parseRhs()
-			} else {
-				x = p.makeExpr(s, "boolean expression")
-				s = nil
-			}
-		}
-		p.exprLev = prevLev
-	}
-
-	body := p.parseBlockStmt()
-	var else_ ast.Stmt
-	if p.tok == token.ELSE {
-		p.next()
-		else_ = p.parseStmt()
-	} else {
-		p.expectSemi()
-	}
-
-	return &ast.IfStmt{If: pos, Init: s, Cond: x, Body: body, Else: else_}
-}
-
-func (p *parser) parseTypeList() (list []ast.Expr) {
-	if p.trace {
-		defer un(trace(p, "TypeList"))
-	}
-
-	list = append(list, p.parseType())
-	for p.tok == token.COMMA {
-		p.next()
-		list = append(list, p.parseType())
-	}
-
-	return
-}
-
-func (p *parser) parseCaseClause(typeSwitch bool) *ast.CaseClause {
-	if p.trace {
-		defer un(trace(p, "CaseClause"))
-	}
-
-	pos := p.pos
-	var list []ast.Expr
-	if p.tok == token.CASE {
-		p.next()
-		if typeSwitch {
-			list = p.parseTypeList()
-		} else {
-			list = p.parseRhsList()
-		}
-	} else {
-		p.expect(token.DEFAULT)
-	}
-
-	colon := p.expect(token.COLON)
-	p.openScope()
-	body := p.parseStmtList()
-	p.closeScope()
-
-	return &ast.CaseClause{Case: pos, List: list, Colon: colon, Body: body}
-}
-
-func isTypeSwitchAssert(x ast.Expr) bool {
-	a, ok := x.(*ast.TypeAssertExpr)
-	return ok && a.Type == nil
-}
-
-func isTypeSwitchGuard(s ast.Stmt) bool {
-	switch t := s.(type) {
-	case *ast.ExprStmt:
-		// x.(nil)
-		return isTypeSwitchAssert(t.X)
-	case *ast.AssignStmt:
-		// v := x.(nil)
-		return len(t.Lhs) == 1 && t.Tok == token.DEFINE && len(t.Rhs) == 1 && isTypeSwitchAssert(t.Rhs[0])
-	}
-	return false
-}
-
-func (p *parser) parseSwitchStmt() ast.Stmt {
-	if p.trace {
-		defer un(trace(p, "SwitchStmt"))
-	}
-
-	pos := p.expect(token.SWITCH)
-	p.openScope()
-	defer p.closeScope()
-
-	var s1, s2 ast.Stmt
-	if p.tok != token.LBRACE {
-		prevLev := p.exprLev
-		p.exprLev = -1
-		if p.tok != token.SEMICOLON {
-			s2, _ = p.parseSimpleStmt(basic)
-		}
-		if p.tok == token.SEMICOLON {
-			p.next()
-			s1 = s2
-			s2 = nil
-			if p.tok != token.LBRACE {
-				// A TypeSwitchGuard may declare a variable in addition
-				// to the variable declared in the initial SimpleStmt.
-				// Introduce extra scope to avoid redeclaration errors:
-				//
-				//	switch t := 0; t := x.(T) { ... }
-				//
-				// (this code is not valid Go because the first t
-				// cannot be accessed and thus is never used, the extra
-				// scope is needed for the correct error message).
-				//
-				// If we don't have a type switch, s2 must be an expression.
-				// Having the extra nested but empty scope won't affect it.
-				p.openScope()
-				defer p.closeScope()
-				s2, _ = p.parseSimpleStmt(basic)
-			}
-		}
-		p.exprLev = prevLev
-	}
-
-	typeSwitch := isTypeSwitchGuard(s2)
-	lbrace := p.expect(token.LBRACE)
-	var list []ast.Stmt
-	for p.tok == token.CASE || p.tok == token.DEFAULT {
-		list = append(list, p.parseCaseClause(typeSwitch))
-	}
-	rbrace := p.expect(token.RBRACE)
-	p.expectSemi()
-	body := &ast.BlockStmt{Lbrace: lbrace, List: list, Rbrace: rbrace}
-
-	if typeSwitch {
-		return &ast.TypeSwitchStmt{Switch: pos, Init: s1, Assign: s2, Body: body}
-	}
-
-	return &ast.SwitchStmt{Switch: pos, Init: s1, Tag: p.makeExpr(s2, "switch expression"), Body: body}
-}
-
-func (p *parser) parseCommClause() *ast.CommClause {
-	if p.trace {
-		defer un(trace(p, "CommClause"))
-	}
-
-	p.openScope()
-	pos := p.pos
-	var comm ast.Stmt
-	if p.tok == token.CASE {
-		p.next()
-		lhs := p.parseLhsList()
-		if p.tok == token.ARROW {
-			// SendStmt
-			if len(lhs) > 1 {
-				p.errorExpected(lhs[0].Pos(), "1 expression")
-				// continue with first expression
-			}
-			arrow := p.pos
-			p.next()
-			rhs := p.parseRhs()
-			comm = &ast.SendStmt{Chan: lhs[0], Arrow: arrow, Value: rhs}
-		} else {
-			// RecvStmt
-			if tok := p.tok; tok == token.ASSIGN || tok == token.DEFINE {
-				// RecvStmt with assignment
-				if len(lhs) > 2 {
-					p.errorExpected(lhs[0].Pos(), "1 or 2 expressions")
-					// continue with first two expressions
-					lhs = lhs[0:2]
-				}
-				pos := p.pos
-				p.next()
-				rhs := p.parseRhs()
-				as := &ast.AssignStmt{Lhs: lhs, TokPos: pos, Tok: tok, Rhs: []ast.Expr{rhs}}
-				if tok == token.DEFINE {
-					p.shortVarDecl(as, lhs)
-				}
-				comm = as
-			} else {
-				// lhs must be single receive operation
-				if len(lhs) > 1 {
-					p.errorExpected(lhs[0].Pos(), "1 expression")
-					// continue with first expression
-				}
-				comm = &ast.ExprStmt{X: lhs[0]}
-			}
-		}
-	} else {
-		p.expect(token.DEFAULT)
-	}
-
-	colon := p.expect(token.COLON)
-	body := p.parseStmtList()
-	p.closeScope()
-
-	return &ast.CommClause{Case: pos, Comm: comm, Colon: colon, Body: body}
-}
-
-func (p *parser) parseSelectStmt() *ast.SelectStmt {
-	if p.trace {
-		defer un(trace(p, "SelectStmt"))
-	}
-
-	pos := p.expect(token.SELECT)
-	lbrace := p.expect(token.LBRACE)
-	var list []ast.Stmt
-	for p.tok == token.CASE || p.tok == token.DEFAULT {
-		list = append(list, p.parseCommClause())
-	}
-	rbrace := p.expect(token.RBRACE)
-	p.expectSemi()
-	body := &ast.BlockStmt{Lbrace: lbrace, List: list, Rbrace: rbrace}
-
-	return &ast.SelectStmt{Select: pos, Body: body}
-}
-
-func (p *parser) parseForStmt() ast.Stmt {
-	if p.trace {
-		defer un(trace(p, "ForStmt"))
-	}
-
-	pos := p.expect(token.FOR)
-	p.openScope()
-	defer p.closeScope()
-
-	var s1, s2, s3 ast.Stmt
-	var isRange bool
-	if p.tok != token.LBRACE {
-		prevLev := p.exprLev
-		p.exprLev = -1
-		if p.tok != token.SEMICOLON {
-			s2, isRange = p.parseSimpleStmt(rangeOk)
-		}
-		if !isRange && p.tok == token.SEMICOLON {
-			p.next()
-			s1 = s2
-			s2 = nil
-			if p.tok != token.SEMICOLON {
-				s2, _ = p.parseSimpleStmt(basic)
-			}
-			p.expectSemi()
-			if p.tok != token.LBRACE {
-				s3, _ = p.parseSimpleStmt(basic)
-			}
-		}
-		p.exprLev = prevLev
-	}
-
-	body := p.parseBlockStmt()
-	p.expectSemi()
-
-	if isRange {
-		as := s2.(*ast.AssignStmt)
-		// check lhs
-		var key, value ast.Expr
-		switch len(as.Lhs) {
-		case 2:
-			key, value = as.Lhs[0], as.Lhs[1]
-		case 1:
-			key = as.Lhs[0]
-		default:
-			p.errorExpected(as.Lhs[0].Pos(), "1 or 2 expressions")
-			return &ast.BadStmt{From: pos, To: p.safePos(body.End())}
-		}
-		// parseSimpleStmt returned a right-hand side that
-		// is a single unary expression of the form "range x"
-		x := as.Rhs[0].(*ast.UnaryExpr).X
-		return &ast.RangeStmt{
-			For:    pos,
-			Key:    key,
-			Value:  value,
-			TokPos: as.TokPos,
-			Tok:    as.Tok,
-			X:      x,
-			Body:   body,
-		}
-	}
-
-	// regular for statement
-	return &ast.ForStmt{
-		For:  pos,
-		Init: s1,
-		Cond: p.makeExpr(s2, "boolean or range expression"),
-		Post: s3,
-		Body: body,
-	}
-}
-
-func (p *parser) parseStmt() (s ast.Stmt) {
-	if p.trace {
-		defer un(trace(p, "Statement"))
-	}
-
-	switch p.tok {
-	case token.CONST, token.TYPE, token.VAR:
-		s = &ast.DeclStmt{Decl: p.parseDecl(syncStmt)}
-	case
-		// tokens that may start an expression
-		token.IDENT, token.INT, token.FLOAT, token.IMAG, token.CHAR, token.STRING, token.FUNC, token.LPAREN, // operands
-		token.LBRACK, token.STRUCT, // composite types
-		token.ADD, token.SUB, token.MUL, token.AND, token.XOR, token.ARROW, token.NOT: // unary operators
-		s, _ = p.parseSimpleStmt(labelOk)
-		// because of the required look-ahead, labeled statements are
-		// parsed by parseSimpleStmt - don't expect a semicolon after
-		// them
-		if _, isLabeledStmt := s.(*ast.LabeledStmt); !isLabeledStmt {
-			p.expectSemi()
-		}
-	case token.GO:
-		s = p.parseGoStmt()
-	case token.DEFER:
-		s = p.parseDeferStmt()
-	case token.RETURN:
-		s = p.parseReturnStmt()
-	case token.BREAK, token.CONTINUE, token.GOTO, token.FALLTHROUGH:
-		s = p.parseBranchStmt(p.tok)
-	case token.LBRACE:
-		s = p.parseBlockStmt()
-		p.expectSemi()
-	case token.IF:
-		s = p.parseIfStmt()
-	case token.SWITCH:
-		s = p.parseSwitchStmt()
-	case token.SELECT:
-		s = p.parseSelectStmt()
-	case token.FOR:
-		s = p.parseForStmt()
-	case token.SEMICOLON:
-		s = &ast.EmptyStmt{Semicolon: p.pos}
-		p.next()
-	case token.RBRACE:
-		// a semicolon may be omitted before a closing "}"
-		s = &ast.EmptyStmt{Semicolon: p.pos}
-	default:
-		// no statement found
-		pos := p.pos
-		p.errorExpected(pos, "statement")
-		syncStmt(p)
-		s = &ast.BadStmt{From: pos, To: p.pos}
-	}
-
-	return
-}
-
-// ----------------------------------------------------------------------------
-// Declarations
-
-type parseSpecFunction func(doc *ast.CommentGroup, keyword token.Token, iota int) ast.Spec
-
-func isValidImport(lit string) bool {
-	const illegalChars = `!"#$%&'()*,:;<=>?[\]^{|}` + "`\uFFFD"
-	s, _ := strconv.Unquote(lit) // go/scanner returns a legal string literal
-	for _, r := range s {
-		if !unicode.IsGraphic(r) || unicode.IsSpace(r) || strings.ContainsRune(illegalChars, r) {
-			return false
-		}
-	}
-	return s != ""
-}
-
-func (p *parser) parseImportSpec(doc *ast.CommentGroup, _ token.Token, _ int) ast.Spec {
-	if p.trace {
-		defer un(trace(p, "ImportSpec"))
-	}
-
-	var ident *ast.Ident
-	switch p.tok {
-	case token.PERIOD:
-		ident = &ast.Ident{NamePos: p.pos, Name: "."}
-		p.next()
-	case token.IDENT:
-		ident = p.parseIdent()
-	}
-
-	pos := p.pos
-	var path string
-	if p.tok == token.STRING {
-		path = p.lit
-		if !isValidImport(path) {
-			p.error(pos, "invalid import path: "+path)
-		}
-		p.next()
-	} else {
-		p.expect(token.STRING) // use expect() error handling
-	}
-	p.expectSemi() // call before accessing p.linecomment
-
-	// collect imports
-	spec := &ast.ImportSpec{
-		Doc:     doc,
-		Name:    ident,
-		Path:    &ast.BasicLit{ValuePos: pos, Kind: token.STRING, Value: path},
-		Comment: p.lineComment,
-	}
-	p.imports = append(p.imports, spec)
-
-	return spec
-}
-
-func (p *parser) parseValueSpec(doc *ast.CommentGroup, keyword token.Token, iota int) ast.Spec {
-	if p.trace {
-		defer un(trace(p, keyword.String()+"Spec"))
-	}
-
-	idents := p.parseIdentList()
-	typ := p.tryType()
-	var values []ast.Expr
-	// always permit optional initialization for more tolerant parsing
-	if p.tok == token.ASSIGN {
-		p.next()
-		values = p.parseRhsList()
-	}
-	p.expectSemi() // call before accessing p.linecomment
-
-	// Go spec: The scope of a constant or variable identifier declared inside
-	// a function begins at the end of the ConstSpec or VarSpec and ends at
-	// the end of the innermost containing block.
-	// (Global identifiers are resolved in a separate phase after parsing.)
-	spec := &ast.ValueSpec{
-		Doc:     doc,
-		Names:   idents,
-		Type:    typ,
-		Values:  values,
-		Comment: p.lineComment,
-	}
-	kind := ast.Con
-	if keyword == token.VAR {
-		kind = ast.Var
-	}
-	p.declare(spec, iota, p.topScope, kind, idents...)
-
-	return spec
-}
-
-func (p *parser) parseTypeSpec(doc *ast.CommentGroup, _ token.Token, _ int) ast.Spec {
-	if p.trace {
-		defer un(trace(p, "TypeSpec"))
-	}
-
-	ident := p.parseIdent()
-
-	// Go spec: The scope of a type identifier declared inside a function begins
-	// at the identifier in the TypeSpec and ends at the end of the innermost
-	// containing block.
-	// (Global identifiers are resolved in a separate phase after parsing.)
-	spec := &ast.TypeSpec{Doc: doc, Name: ident}
-	p.declare(spec, nil, p.topScope, ast.Typ, ident)
-
-	spec.Type = p.parseType()
-	p.expectSemi() // call before accessing p.linecomment
-	spec.Comment = p.lineComment
-
-	return spec
-}
-
-func (p *parser) parseGenDecl(keyword token.Token, f parseSpecFunction) *ast.GenDecl {
-	if p.trace {
-		defer un(trace(p, "GenDecl("+keyword.String()+")"))
-	}
-
-	doc := p.leadComment
-	pos := p.expect(keyword)
-	var lparen, rparen token.Pos
-	var list []ast.Spec
-	if p.tok == token.LPAREN {
-		lparen = p.pos
-		p.next()
-		for iota := 0; p.tok != token.RPAREN && p.tok != token.EOF; iota++ {
-			list = append(list, f(p.leadComment, keyword, iota))
-		}
-		rparen = p.expect(token.RPAREN)
-		p.expectSemi()
-	} else {
-		list = append(list, f(nil, keyword, 0))
-	}
-
-	return &ast.GenDecl{
-		Doc:    doc,
-		TokPos: pos,
-		Tok:    keyword,
-		Lparen: lparen,
-		Specs:  list,
-		Rparen: rparen,
-	}
-}
-
-func (p *parser) parseReceiver(scope *ast.Scope) *ast.FieldList {
-	if p.trace {
-		defer un(trace(p, "Receiver"))
-	}
-
-	par := p.parseParameters(scope, false)
-
-	// must have exactly one receiver
-	if par.NumFields() != 1 {
-		p.errorExpected(par.Opening, "exactly one receiver")
-		par.List = []*ast.Field{{Type: &ast.BadExpr{From: par.Opening, To: par.Closing + 1}}}
-		return par
-	}
-
-	// recv type must be of the form ["*"] identifier
-	recv := par.List[0]
-	base := deref(recv.Type)
-	if _, isIdent := base.(*ast.Ident); !isIdent {
-		if _, isBad := base.(*ast.BadExpr); !isBad {
-			// only report error if it's a new one
-			p.errorExpected(base.Pos(), "(unqualified) identifier")
-		}
-		par.List = []*ast.Field{
-			{Type: &ast.BadExpr{From: recv.Pos(), To: p.safePos(recv.End())}},
-		}
-	}
-
-	return par
-}
-
-func (p *parser) parseFuncDecl() *ast.FuncDecl {
-	if p.trace {
-		defer un(trace(p, "FunctionDecl"))
-	}
-
-	doc := p.leadComment
-	pos := p.expect(token.FUNC)
-	scope := ast.NewScope(p.topScope) // function scope
-
-	var recv *ast.FieldList
-	if p.tok == token.LPAREN {
-		recv = p.parseReceiver(scope)
-	}
-
-	ident := p.parseIdent()
-
-	params, results := p.parseSignature(scope)
-
-	var body *ast.BlockStmt
-	if p.tok == token.LBRACE {
-		body = p.parseBody(scope)
-	}
-	p.expectSemi()
-
-	decl := &ast.FuncDecl{
-		Doc:  doc,
-		Recv: recv,
-		Name: ident,
-		Type: &ast.FuncType{
-			Func:    pos,
-			Params:  params,
-			Results: results,
-		},
-		Body: body,
-	}
-	if recv == nil {
-		// Go spec: The scope of an identifier denoting a constant, type,
-		// variable, or function (but not method) declared at top level
-		// (outside any function) is the package block.
-		//
-		// init() functions cannot be referred to and there may
-		// be more than one - don't put them in the pkgScope
-		if ident.Name != "init" {
-			p.declare(decl, nil, p.pkgScope, ast.Fun, ident)
-		}
-	}
-
-	return decl
-}
-
-func (p *parser) parseDecl(sync func(*parser)) ast.Decl {
-	if p.trace {
-		defer un(trace(p, "Declaration"))
-	}
-
-	var f parseSpecFunction
-	switch p.tok {
-	case token.CONST, token.VAR:
-		f = p.parseValueSpec
-
-	case token.TYPE:
-		f = p.parseTypeSpec
-
-	case token.FUNC:
-		return p.parseFuncDecl()
-
-	default:
-		pos := p.pos
-		p.errorExpected(pos, "declaration")
-		sync(p)
-		return &ast.BadDecl{From: pos, To: p.pos}
-	}
-
-	return p.parseGenDecl(p.tok, f)
-}
-
-// ----------------------------------------------------------------------------
-// Source files
-
-func (p *parser) parseFile() *ast.File {
-	if p.trace {
-		defer un(trace(p, "File"))
-	}
-
-	// Don't bother parsing the rest if we had errors scanning the first token.
-	// Likely not a Go source file at all.
-	if p.errors.Len() != 0 {
-		return nil
-	}
-
-	// package clause
-	doc := p.leadComment
-	pos := p.expect(token.PACKAGE)
-	// Go spec: The package clause is not a declaration;
-	// the package name does not appear in any scope.
-	ident := p.parseIdent()
-	if ident.Name == "_" && p.mode&DeclarationErrors != 0 {
-		p.error(p.pos, "invalid package name _")
-	}
-	p.expectSemi()
-
-	// Don't bother parsing the rest if we had errors parsing the package clause.
-	// Likely not a Go source file at all.
-	if p.errors.Len() != 0 {
-		return nil
-	}
-
-	p.openScope()
-	p.pkgScope = p.topScope
-	var decls []ast.Decl
-	if p.mode&PackageClauseOnly == 0 {
-		// import decls
-		for p.tok == token.IMPORT {
-			decls = append(decls, p.parseGenDecl(token.IMPORT, p.parseImportSpec))
-		}
-
-		if p.mode&ImportsOnly == 0 {
-			// rest of package body
-			for p.tok != token.EOF {
-				decls = append(decls, p.parseDecl(syncDecl))
-			}
-		}
-	}
-	p.closeScope()
-	assert(p.topScope == nil, "unbalanced scopes")
-	assert(p.labelScope == nil, "unbalanced label scopes")
-
-	// resolve global identifiers within the same file
-	i := 0
-	for _, ident := range p.unresolved {
-		// i <= index for current ident
-		assert(ident.Obj == unresolved, "object already resolved")
-		ident.Obj = p.pkgScope.Lookup(ident.Name) // also removes unresolved sentinel
-		if ident.Obj == nil {
-			p.unresolved[i] = ident
-			i++
-		}
-	}
-
-	return &ast.File{
-		Doc:        doc,
-		Package:    pos,
-		Name:       ident,
-		Decls:      decls,
-		Scope:      p.pkgScope,
-		Imports:    p.imports,
-		Unresolved: p.unresolved[0:i],
-		Comments:   p.comments,
-	}
-}
diff --git a/src/pkg/go/parser/parser_test.go b/src/pkg/go/parser/parser_test.go
deleted file mode 100644
index 2797ea518..000000000
--- a/src/pkg/go/parser/parser_test.go
+++ /dev/null
@@ -1,431 +0,0 @@
-// 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.
-
-package parser
-
-import (
-	"bytes"
-	"fmt"
-	"go/ast"
-	"go/token"
-	"os"
-	"strings"
-	"testing"
-)
-
-var fset = token.NewFileSet()
-
-var validFiles = []string{
-	"parser.go",
-	"parser_test.go",
-	"error_test.go",
-	"short_test.go",
-}
-
-func TestParse(t *testing.T) {
-	for _, filename := range validFiles {
-		_, err := ParseFile(fset, filename, nil, DeclarationErrors)
-		if err != nil {
-			t.Fatalf("ParseFile(%s): %v", filename, err)
-		}
-	}
-}
-
-func nameFilter(filename string) bool {
-	switch filename {
-	case "parser.go", "interface.go", "parser_test.go":
-		return true
-	case "parser.go.orig":
-		return true // permit but should be ignored by ParseDir
-	}
-	return false
-}
-
-func dirFilter(f os.FileInfo) bool { return nameFilter(f.Name()) }
-
-func TestParseDir(t *testing.T) {
-	path := "."
-	pkgs, err := ParseDir(fset, path, dirFilter, 0)
-	if err != nil {
-		t.Fatalf("ParseDir(%s): %v", path, err)
-	}
-	if n := len(pkgs); n != 1 {
-		t.Errorf("got %d packages; want 1", n)
-	}
-	pkg := pkgs["parser"]
-	if pkg == nil {
-		t.Errorf(`package "parser" not found`)
-		return
-	}
-	if n := len(pkg.Files); n != 3 {
-		t.Errorf("got %d package files; want 3", n)
-	}
-	for filename := range pkg.Files {
-		if !nameFilter(filename) {
-			t.Errorf("unexpected package file: %s", filename)
-		}
-	}
-}
-
-func TestParseExpr(t *testing.T) {
-	// just kicking the tires:
-	// a valid arithmetic expression
-	src := "a + b"
-	x, err := ParseExpr(src)
-	if err != nil {
-		t.Fatalf("ParseExpr(%s): %v", src, err)
-	}
-	// sanity check
-	if _, ok := x.(*ast.BinaryExpr); !ok {
-		t.Errorf("ParseExpr(%s): got %T, want *ast.BinaryExpr", src, x)
-	}
-
-	// a valid type expression
-	src = "struct{x *int}"
-	x, err = ParseExpr(src)
-	if err != nil {
-		t.Fatalf("ParseExpr(%s): %v", src, err)
-	}
-	// sanity check
-	if _, ok := x.(*ast.StructType); !ok {
-		t.Errorf("ParseExpr(%s): got %T, want *ast.StructType", src, x)
-	}
-
-	// an invalid expression
-	src = "a + *"
-	_, err = ParseExpr(src)
-	if err == nil {
-		t.Fatalf("ParseExpr(%s): got no error", src)
-	}
-
-	// a valid expression followed by extra tokens is invalid
-	src = "a[i] := x"
-	_, err = ParseExpr(src)
-	if err == nil {
-		t.Fatalf("ParseExpr(%s): got no error", src)
-	}
-
-	// ParseExpr must not crash
-	for _, src := range valids {
-		ParseExpr(src)
-	}
-}
-
-func TestColonEqualsScope(t *testing.T) {
-	f, err := ParseFile(fset, "", `package p; func f() { x, y, z := x, y, z }`, 0)
-	if err != nil {
-		t.Fatal(err)
-	}
-
-	// RHS refers to undefined globals; LHS does not.
-	as := f.Decls[0].(*ast.FuncDecl).Body.List[0].(*ast.AssignStmt)
-	for _, v := range as.Rhs {
-		id := v.(*ast.Ident)
-		if id.Obj != nil {
-			t.Errorf("rhs %s has Obj, should not", id.Name)
-		}
-	}
-	for _, v := range as.Lhs {
-		id := v.(*ast.Ident)
-		if id.Obj == nil {
-			t.Errorf("lhs %s does not have Obj, should", id.Name)
-		}
-	}
-}
-
-func TestVarScope(t *testing.T) {
-	f, err := ParseFile(fset, "", `package p; func f() { var x, y, z = x, y, z }`, 0)
-	if err != nil {
-		t.Fatal(err)
-	}
-
-	// RHS refers to undefined globals; LHS does not.
-	as := f.Decls[0].(*ast.FuncDecl).Body.List[0].(*ast.DeclStmt).Decl.(*ast.GenDecl).Specs[0].(*ast.ValueSpec)
-	for _, v := range as.Values {
-		id := v.(*ast.Ident)
-		if id.Obj != nil {
-			t.Errorf("rhs %s has Obj, should not", id.Name)
-		}
-	}
-	for _, id := range as.Names {
-		if id.Obj == nil {
-			t.Errorf("lhs %s does not have Obj, should", id.Name)
-		}
-	}
-}
-
-func TestObjects(t *testing.T) {
-	const src = `
-package p
-import fmt "fmt"
-const pi = 3.14
-type T struct{}
-var x int
-func f() { L: }
-`
-
-	f, err := ParseFile(fset, "", src, 0)
-	if err != nil {
-		t.Fatal(err)
-	}
-
-	objects := map[string]ast.ObjKind{
-		"p":   ast.Bad, // not in a scope
-		"fmt": ast.Bad, // not resolved yet
-		"pi":  ast.Con,
-		"T":   ast.Typ,
-		"x":   ast.Var,
-		"int": ast.Bad, // not resolved yet
-		"f":   ast.Fun,
-		"L":   ast.Lbl,
-	}
-
-	ast.Inspect(f, func(n ast.Node) bool {
-		if ident, ok := n.(*ast.Ident); ok {
-			obj := ident.Obj
-			if obj == nil {
-				if objects[ident.Name] != ast.Bad {
-					t.Errorf("no object for %s", ident.Name)
-				}
-				return true
-			}
-			if obj.Name != ident.Name {
-				t.Errorf("names don't match: obj.Name = %s, ident.Name = %s", obj.Name, ident.Name)
-			}
-			kind := objects[ident.Name]
-			if obj.Kind != kind {
-				t.Errorf("%s: obj.Kind = %s; want %s", ident.Name, obj.Kind, kind)
-			}
-		}
-		return true
-	})
-}
-
-func TestUnresolved(t *testing.T) {
-	f, err := ParseFile(fset, "", `
-package p
-//
-func f1a(int)
-func f2a(byte, int, float)
-func f3a(a, b int, c float)
-func f4a(...complex)
-func f5a(a s1a, b ...complex)
-//
-func f1b(*int)
-func f2b([]byte, (int), *float)
-func f3b(a, b *int, c []float)
-func f4b(...*complex)
-func f5b(a s1a, b ...[]complex)
-//
-type s1a struct { int }
-type s2a struct { byte; int; s1a }
-type s3a struct { a, b int; c float }
-//
-type s1b struct { *int }
-type s2b struct { byte; int; *float }
-type s3b struct { a, b *s3b; c []float }
-`, 0)
-	if err != nil {
-		t.Fatal(err)
-	}
-
-	want := "int " + // f1a
-		"byte int float " + // f2a
-		"int float " + // f3a
-		"complex " + // f4a
-		"complex " + // f5a
-		//
-		"int " + // f1b
-		"byte int float " + // f2b
-		"int float " + // f3b
-		"complex " + // f4b
-		"complex " + // f5b
-		//
-		"int " + // s1a
-		"byte int " + // s2a
-		"int float " + // s3a
-		//
-		"int " + // s1a
-		"byte int float " + // s2a
-		"float " // s3a
-
-	// collect unresolved identifiers
-	var buf bytes.Buffer
-	for _, u := range f.Unresolved {
-		buf.WriteString(u.Name)
-		buf.WriteByte(' ')
-	}
-	got := buf.String()
-
-	if got != want {
-		t.Errorf("\ngot:  %s\nwant: %s", got, want)
-	}
-}
-
-var imports = map[string]bool{
-	`"a"`:        true,
-	"`a`":        true,
-	`"a/b"`:      true,
-	`"a.b"`:      true,
-	`"m\x61th"`:  true,
-	`"greek/αβ"`: true,
-	`""`:         false,
-
-	// Each of these pairs tests both `` vs "" strings
-	// and also use of invalid characters spelled out as
-	// escape sequences and written directly.
-	// For example `"\x00"` tests import "\x00"
-	// while "`\x00`" tests import `<actual-NUL-byte>`.
-	`"\x00"`:     false,
-	"`\x00`":     false,
-	`"\x7f"`:     false,
-	"`\x7f`":     false,
-	`"a!"`:       false,
-	"`a!`":       false,
-	`"a b"`:      false,
-	"`a b`":      false,
-	`"a\\b"`:     false,
-	"`a\\b`":     false,
-	"\"`a`\"":    false,
-	"`\"a\"`":    false,
-	`"\x80\x80"`: false,
-	"`\x80\x80`": false,
-	`"\xFFFD"`:   false,
-	"`\xFFFD`":   false,
-}
-
-func TestImports(t *testing.T) {
-	for path, isValid := range imports {
-		src := fmt.Sprintf("package p; import %s", path)
-		_, err := ParseFile(fset, "", src, 0)
-		switch {
-		case err != nil && isValid:
-			t.Errorf("ParseFile(%s): got %v; expected no error", src, err)
-		case err == nil && !isValid:
-			t.Errorf("ParseFile(%s): got no error; expected one", src)
-		}
-	}
-}
-
-func TestCommentGroups(t *testing.T) {
-	f, err := ParseFile(fset, "", `
-package p /* 1a */ /* 1b */      /* 1c */ // 1d
-/* 2a
-*/
-// 2b
-const pi = 3.1415
-/* 3a */ // 3b
-/* 3c */ const e = 2.7182
-
-// Example from issue 3139
-func ExampleCount() {
-	fmt.Println(strings.Count("cheese", "e"))
-	fmt.Println(strings.Count("five", "")) // before & after each rune
-	// Output:
-	// 3
-	// 5
-}
-`, ParseComments)
-	if err != nil {
-		t.Fatal(err)
-	}
-	expected := [][]string{
-		{"/* 1a */", "/* 1b */", "/* 1c */", "// 1d"},
-		{"/* 2a\n*/", "// 2b"},
-		{"/* 3a */", "// 3b", "/* 3c */"},
-		{"// Example from issue 3139"},
-		{"// before & after each rune"},
-		{"// Output:", "// 3", "// 5"},
-	}
-	if len(f.Comments) != len(expected) {
-		t.Fatalf("got %d comment groups; expected %d", len(f.Comments), len(expected))
-	}
-	for i, exp := range expected {
-		got := f.Comments[i].List
-		if len(got) != len(exp) {
-			t.Errorf("got %d comments in group %d; expected %d", len(got), i, len(exp))
-			continue
-		}
-		for j, exp := range exp {
-			got := got[j].Text
-			if got != exp {
-				t.Errorf("got %q in group %d; expected %q", got, i, exp)
-			}
-		}
-	}
-}
-
-func getField(file *ast.File, fieldname string) *ast.Field {
-	parts := strings.Split(fieldname, ".")
-	for _, d := range file.Decls {
-		if d, ok := d.(*ast.GenDecl); ok && d.Tok == token.TYPE {
-			for _, s := range d.Specs {
-				if s, ok := s.(*ast.TypeSpec); ok && s.Name.Name == parts[0] {
-					if s, ok := s.Type.(*ast.StructType); ok {
-						for _, f := range s.Fields.List {
-							for _, name := range f.Names {
-								if name.Name == parts[1] {
-									return f
-								}
-							}
-						}
-					}
-				}
-			}
-		}
-	}
-	return nil
-}
-
-// Don't use ast.CommentGroup.Text() - we want to see exact comment text.
-func commentText(c *ast.CommentGroup) string {
-	var buf bytes.Buffer
-	if c != nil {
-		for _, c := range c.List {
-			buf.WriteString(c.Text)
-		}
-	}
-	return buf.String()
-}
-
-func checkFieldComments(t *testing.T, file *ast.File, fieldname, lead, line string) {
-	f := getField(file, fieldname)
-	if f == nil {
-		t.Fatalf("field not found: %s", fieldname)
-	}
-	if got := commentText(f.Doc); got != lead {
-		t.Errorf("got lead comment %q; expected %q", got, lead)
-	}
-	if got := commentText(f.Comment); got != line {
-		t.Errorf("got line comment %q; expected %q", got, line)
-	}
-}
-
-func TestLeadAndLineComments(t *testing.T) {
-	f, err := ParseFile(fset, "", `
-package p
-type T struct {
-	/* F1 lead comment */
-	//
-	F1 int  /* F1 */ // line comment
-	// F2 lead
-	// comment
-	F2 int  // F2 line comment
-	// f3 lead comment
-	f3 int  // f3 line comment
-}
-`, ParseComments)
-	if err != nil {
-		t.Fatal(err)
-	}
-	checkFieldComments(t, f, "T.F1", "/* F1 lead comment *///", "/* F1 */// line comment")
-	checkFieldComments(t, f, "T.F2", "// F2 lead// comment", "// F2 line comment")
-	checkFieldComments(t, f, "T.f3", "// f3 lead comment", "// f3 line comment")
-	ast.FileExports(f)
-	checkFieldComments(t, f, "T.F1", "/* F1 lead comment *///", "/* F1 */// line comment")
-	checkFieldComments(t, f, "T.F2", "// F2 lead// comment", "// F2 line comment")
-	if getField(f, "T.f3") != nil {
-		t.Error("not expected to find T.f3")
-	}
-}
diff --git a/src/pkg/go/parser/performance_test.go b/src/pkg/go/parser/performance_test.go
deleted file mode 100644
index f2732c0e2..000000000
--- a/src/pkg/go/parser/performance_test.go
+++ /dev/null
@@ -1,30 +0,0 @@
-// 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 parser
-
-import (
-	"go/token"
-	"io/ioutil"
-	"testing"
-)
-
-var src = readFile("parser.go")
-
-func readFile(filename string) []byte {
-	data, err := ioutil.ReadFile(filename)
-	if err != nil {
-		panic(err)
-	}
-	return data
-}
-
-func BenchmarkParse(b *testing.B) {
-	b.SetBytes(int64(len(src)))
-	for i := 0; i < b.N; i++ {
-		if _, err := ParseFile(token.NewFileSet(), "", src, ParseComments); err != nil {
-			b.Fatalf("benchmark failed due to parse error: %s", err)
-		}
-	}
-}
diff --git a/src/pkg/go/parser/short_test.go b/src/pkg/go/parser/short_test.go
deleted file mode 100644
index b79406099..000000000
--- a/src/pkg/go/parser/short_test.go
+++ /dev/null
@@ -1,98 +0,0 @@
-// 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.
-
-// This file contains test cases for short valid and invalid programs.
-
-package parser
-
-import "testing"
-
-var valids = []string{
-	"package p\n",
-	`package p;`,
-	`package p; import "fmt"; func f() { fmt.Println("Hello, World!") };`,
-	`package p; func f() { if f(T{}) {} };`,
-	`package p; func f() { _ = <-chan int(nil) };`,
-	`package p; func f() { _ = (<-chan int)(nil) };`,
-	`package p; func f() { _ = (<-chan <-chan int)(nil) };`,
-	`package p; func f() { _ = <-chan <-chan <-chan <-chan <-int(nil) };`,
-	`package p; func f(func() func() func());`,
-	`package p; func f(...T);`,
-	`package p; func f(float, ...int);`,
-	`package p; func f(x int, a ...int) { f(0, a...); f(1, a...,) };`,
-	`package p; func f(int,) {};`,
-	`package p; func f(...int,) {};`,
-	`package p; func f(x ...int,) {};`,
-	`package p; type T []int; var a []bool; func f() { if a[T{42}[0]] {} };`,
-	`package p; type T []int; func g(int) bool { return true }; func f() { if g(T{42}[0]) {} };`,
-	`package p; type T []int; func f() { for _ = range []int{T{42}[0]} {} };`,
-	`package p; var a = T{{1, 2}, {3, 4}}`,
-	`package p; func f() { select { case <- c: case c <- d: case c <- <- d: case <-c <- d: } };`,
-	`package p; func f() { select { case x := (<-c): } };`,
-	`package p; func f() { if ; true {} };`,
-	`package p; func f() { switch ; {} };`,
-	`package p; func f() { for _ = range "foo" + "bar" {} };`,
-	`package p; func f() { var s []int; g(s[:], s[i:], s[:j], s[i:j], s[i:j:k], s[:j:k]) };`,
-	`package p; var ( _ = (struct {*T}).m; _ = (interface {T}).m )`,
-}
-
-func TestValid(t *testing.T) {
-	for _, src := range valids {
-		checkErrors(t, src, src)
-	}
-}
-
-var invalids = []string{
-	`foo /* ERROR "expected 'package'" */ !`,
-	`package p; func f() { if { /* ERROR "expected operand" */ } };`,
-	`package p; func f() { if ; { /* ERROR "expected operand" */ } };`,
-	`package p; func f() { if f(); { /* ERROR "expected operand" */ } };`,
-	`package p; func f() { if _ /* ERROR "expected boolean expression" */ = range x; true {} };`,
-	`package p; func f() { switch _ /* ERROR "expected switch expression" */ = range x; true {} };`,
-	`package p; func f() { for _ = range x ; /* ERROR "expected '{'" */ ; {} };`,
-	`package p; func f() { for ; ; _ = range /* ERROR "expected operand" */ x {} };`,
-	`package p; func f() { for ; _ /* ERROR "expected boolean or range expression" */ = range x ; {} };`,
-	`package p; func f() { switch t /* ERROR "expected switch expression" */ = t.(type) {} };`,
-	`package p; func f() { switch t /* ERROR "expected switch expression" */ , t = t.(type) {} };`,
-	`package p; func f() { switch t /* ERROR "expected switch expression" */ = t.(type), t {} };`,
-	`package p; var a = [ /* ERROR "expected expression" */ 1]int;`,
-	`package p; var a = [ /* ERROR "expected expression" */ ...]int;`,
-	`package p; var a = struct /* ERROR "expected expression" */ {}`,
-	`package p; var a = func /* ERROR "expected expression" */ ();`,
-	`package p; var a = interface /* ERROR "expected expression" */ {}`,
-	`package p; var a = [ /* ERROR "expected expression" */ ]int`,
-	`package p; var a = map /* ERROR "expected expression" */ [int]int`,
-	`package p; var a = chan /* ERROR "expected expression" */ int;`,
-	`package p; var a = []int{[ /* ERROR "expected expression" */ ]int};`,
-	`package p; var a = ( /* ERROR "expected expression" */ []int);`,
-	`package p; var a = a[[ /* ERROR "expected expression" */ ]int:[]int];`,
-	`package p; var a = <- /* ERROR "expected expression" */ chan int;`,
-	`package p; func f() { select { case _ <- chan /* ERROR "expected expression" */ int: } };`,
-	`package p; func f() { _ = (<-<- /* ERROR "expected 'chan'" */ chan int)(nil) };`,
-	`package p; func f() { _ = (<-chan<-chan<-chan<-chan<-chan<- /* ERROR "expected channel type" */ int)(nil) };`,
-	`package p; func f() { var t []int; t /* ERROR "expected identifier on left side of :=" */ [0] := 0 };`,
-	`package p; func f() { if x := g(); x = /* ERROR "expected '=='" */ 0 {}};`,
-	`package p; func f() { _ = x = /* ERROR "expected '=='" */ 0 {}};`,
-	`package p; func f() { _ = 1 == func()int { var x bool; x = x = /* ERROR "expected '=='" */ true; return x }() };`,
-	`package p; func f() { var s []int; _ = s[] /* ERROR "expected operand" */ };`,
-	`package p; func f() { var s []int; _ = s[i:j: /* ERROR "3rd index required" */ ] };`,
-	`package p; func f() { var s []int; _ = s[i: /* ERROR "2nd index required" */ :k] };`,
-	`package p; func f() { var s []int; _ = s[i: /* ERROR "2nd index required" */ :] };`,
-	`package p; func f() { var s []int; _ = s[: /* ERROR "2nd index required" */ :] };`,
-	`package p; func f() { var s []int; _ = s[: /* ERROR "2nd index required" */ ::] };`,
-	`package p; func f() { var s []int; _ = s[i:j:k: /* ERROR "expected ']'" */ l] };`,
-	`package p; func f() { for x /* ERROR "boolean or range expression" */ = []string {} }`,
-	`package p; func f() { for x /* ERROR "boolean or range expression" */ := []string {} }`,
-	`package p; func f() { for i /* ERROR "boolean or range expression" */ , x = []string {} }`,
-	`package p; func f() { for i /* ERROR "boolean or range expression" */ , x := []string {} }`,
-	`package p; func f() { go f /* ERROR HERE "function must be invoked" */ }`,
-	`package p; func f() { defer func() {} /* ERROR HERE "function must be invoked" */ }`,
-	`package p; func f() { go func() { func() { f(x func /* ERROR "expected '\)'" */ (){}) } } }`,
-}
-
-func TestInvalid(t *testing.T) {
-	for _, src := range invalids {
-		checkErrors(t, src, src)
-	}
-}
diff --git a/src/pkg/go/parser/testdata/commas.src b/src/pkg/go/parser/testdata/commas.src
deleted file mode 100644
index af6e70645..000000000
--- a/src/pkg/go/parser/testdata/commas.src
+++ /dev/null
@@ -1,19 +0,0 @@
-// 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.
-
-// Test case for error messages/parser synchronization
-// after missing commas.
-
-package p
-
-var _ = []int{
-	0 /* ERROR "missing ','" */
-}
-
-var _ = []int{
-	0,
-	1,
-	2,
-	3 /* ERROR "missing ','" */
-}
diff --git a/src/pkg/go/parser/testdata/issue3106.src b/src/pkg/go/parser/testdata/issue3106.src
deleted file mode 100644
index 82796c8ce..000000000
--- a/src/pkg/go/parser/testdata/issue3106.src
+++ /dev/null
@@ -1,46 +0,0 @@
-// 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.
-
-// Test case for issue 3106: Better synchronization of
-// parser after certain syntax errors.
-
-package main
-
-func f() {
-	var m Mutex
-	c := MakeCond(&m)
-	percent := 0
-	const step = 10
-	for i := 0; i < 5; i++ {
-		go func() {
-			for {
-				// Emulates some useful work.
-				time.Sleep(1e8)
-				m.Lock()
-				defer
-				if /* ERROR "expected operand, found 'if'" */ percent == 100 {
-					m.Unlock()
-					break
-				}
-				percent++
-				if percent % step == 0 {
-					//c.Signal()
-				}
-				m.Unlock()
-			}
-		}()
-	}
-	for {
-		m.Lock()
-		if percent == 0 || percent % step != 0 {
-			c.Wait()
-		}
-		fmt.Print(",")
-		if percent == 100 {
-			m.Unlock()
-			break
-		}
-		m.Unlock()
-	}
-}