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-rw-r--r--gcc-4.8.1/libgo/go/go/doc/example.go332
1 files changed, 0 insertions, 332 deletions
diff --git a/gcc-4.8.1/libgo/go/go/doc/example.go b/gcc-4.8.1/libgo/go/go/doc/example.go
deleted file mode 100644
index f634e1677..000000000
--- a/gcc-4.8.1/libgo/go/go/doc/example.go
+++ /dev/null
@@ -1,332 +0,0 @@
-// Copyright 2011 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.
-
-// Extract example functions from file ASTs.
-
-package doc
-
-import (
- "go/ast"
- "go/token"
- "path"
- "regexp"
- "sort"
- "strconv"
- "strings"
- "unicode"
- "unicode/utf8"
-)
-
-type Example struct {
- Name string // name of the item being exemplified
- Doc string // example function doc string
- Code ast.Node
- Play *ast.File // a whole program version of the example
- Comments []*ast.CommentGroup
- Output string // expected output
- EmptyOutput bool // expect empty output
-}
-
-func Examples(files ...*ast.File) []*Example {
- var list []*Example
- for _, file := range files {
- hasTests := false // file contains tests or benchmarks
- numDecl := 0 // number of non-import declarations in the file
- var flist []*Example
- for _, decl := range file.Decls {
- if g, ok := decl.(*ast.GenDecl); ok && g.Tok != token.IMPORT {
- numDecl++
- continue
- }
- f, ok := decl.(*ast.FuncDecl)
- if !ok {
- continue
- }
- numDecl++
- name := f.Name.Name
- if isTest(name, "Test") || isTest(name, "Benchmark") {
- hasTests = true
- continue
- }
- if !isTest(name, "Example") {
- continue
- }
- var doc string
- if f.Doc != nil {
- doc = f.Doc.Text()
- }
- output, hasOutput := exampleOutput(f.Body, file.Comments)
- flist = append(flist, &Example{
- Name: name[len("Example"):],
- Doc: doc,
- Code: f.Body,
- Play: playExample(file, f.Body),
- Comments: file.Comments,
- Output: output,
- EmptyOutput: output == "" && hasOutput,
- })
- }
- if !hasTests && numDecl > 1 && len(flist) == 1 {
- // If this file only has one example function, some
- // other top-level declarations, and no tests or
- // benchmarks, use the whole file as the example.
- flist[0].Code = file
- flist[0].Play = playExampleFile(file)
- }
- list = append(list, flist...)
- }
- sort.Sort(exampleByName(list))
- return list
-}
-
-var outputPrefix = regexp.MustCompile(`(?i)^[[:space:]]*output:`)
-
-// Extracts the expected output and whether there was a valid output comment
-func exampleOutput(b *ast.BlockStmt, comments []*ast.CommentGroup) (output string, ok bool) {
- if _, last := lastComment(b, comments); last != nil {
- // test that it begins with the correct prefix
- text := last.Text()
- if loc := outputPrefix.FindStringIndex(text); loc != nil {
- text = text[loc[1]:]
- // Strip zero or more spaces followed by \n or a single space.
- text = strings.TrimLeft(text, " ")
- if len(text) > 0 && text[0] == '\n' {
- text = text[1:]
- }
- return text, true
- }
- }
- return "", false // no suitable comment found
-}
-
-// isTest tells whether name looks like a test, example, or benchmark.
-// It is a Test (say) if there is a character after Test that is not a
-// lower-case letter. (We don't want Testiness.)
-func isTest(name, prefix string) bool {
- if !strings.HasPrefix(name, prefix) {
- return false
- }
- if len(name) == len(prefix) { // "Test" is ok
- return true
- }
- rune, _ := utf8.DecodeRuneInString(name[len(prefix):])
- return !unicode.IsLower(rune)
-}
-
-type exampleByName []*Example
-
-func (s exampleByName) Len() int { return len(s) }
-func (s exampleByName) Swap(i, j int) { s[i], s[j] = s[j], s[i] }
-func (s exampleByName) Less(i, j int) bool { return s[i].Name < s[j].Name }
-
-// playExample synthesizes a new *ast.File based on the provided
-// file with the provided function body as the body of main.
-func playExample(file *ast.File, body *ast.BlockStmt) *ast.File {
- if !strings.HasSuffix(file.Name.Name, "_test") {
- // We don't support examples that are part of the
- // greater package (yet).
- return nil
- }
-
- // Find top-level declarations in the file.
- topDecls := make(map[*ast.Object]bool)
- for _, decl := range file.Decls {
- switch d := decl.(type) {
- case *ast.FuncDecl:
- topDecls[d.Name.Obj] = true
- case *ast.GenDecl:
- for _, spec := range d.Specs {
- switch s := spec.(type) {
- case *ast.TypeSpec:
- topDecls[s.Name.Obj] = true
- case *ast.ValueSpec:
- for _, id := range s.Names {
- topDecls[id.Obj] = true
- }
- }
- }
- }
- }
-
- // Find unresolved identifiers and uses of top-level declarations.
- unresolved := make(map[string]bool)
- usesTopDecl := false
- var inspectFunc func(ast.Node) bool
- inspectFunc = func(n ast.Node) bool {
- // For selector expressions, only inspect the left hand side.
- // (For an expression like fmt.Println, only add "fmt" to the
- // set of unresolved names, not "Println".)
- if e, ok := n.(*ast.SelectorExpr); ok {
- ast.Inspect(e.X, inspectFunc)
- return false
- }
- if id, ok := n.(*ast.Ident); ok {
- if id.Obj == nil {
- unresolved[id.Name] = true
- } else if topDecls[id.Obj] {
- usesTopDecl = true
- }
- }
- return true
- }
- ast.Inspect(body, inspectFunc)
- if usesTopDecl {
- // We don't support examples that are not self-contained (yet).
- return nil
- }
-
- // Remove predeclared identifiers from unresolved list.
- for n := range unresolved {
- if predeclaredTypes[n] || predeclaredConstants[n] || predeclaredFuncs[n] {
- delete(unresolved, n)
- }
- }
-
- // Use unresolved identifiers to determine the imports used by this
- // example. The heuristic assumes package names match base import
- // paths for imports w/o renames (should be good enough most of the time).
- namedImports := make(map[string]string) // [name]path
- var blankImports []ast.Spec // _ imports
- for _, s := range file.Imports {
- p, err := strconv.Unquote(s.Path.Value)
- if err != nil {
- continue
- }
- n := path.Base(p)
- if s.Name != nil {
- n = s.Name.Name
- switch n {
- case "_":
- blankImports = append(blankImports, s)
- continue
- case ".":
- // We can't resolve dot imports (yet).
- return nil
- }
- }
- if unresolved[n] {
- namedImports[n] = p
- delete(unresolved, n)
- }
- }
-
- // If there are other unresolved identifiers, give up because this
- // synthesized file is not going to build.
- if len(unresolved) > 0 {
- return nil
- }
-
- // Include documentation belonging to blank imports.
- var comments []*ast.CommentGroup
- for _, s := range blankImports {
- if c := s.(*ast.ImportSpec).Doc; c != nil {
- comments = append(comments, c)
- }
- }
-
- // Include comments that are inside the function body.
- for _, c := range file.Comments {
- if body.Pos() <= c.Pos() && c.End() <= body.End() {
- comments = append(comments, c)
- }
- }
-
- // Strip "Output:" commment and adjust body end position.
- body, comments = stripOutputComment(body, comments)
-
- // Synthesize import declaration.
- importDecl := &ast.GenDecl{
- Tok: token.IMPORT,
- Lparen: 1, // Need non-zero Lparen and Rparen so that printer
- Rparen: 1, // treats this as a factored import.
- }
- for n, p := range namedImports {
- s := &ast.ImportSpec{Path: &ast.BasicLit{Value: strconv.Quote(p)}}
- if path.Base(p) != n {
- s.Name = ast.NewIdent(n)
- }
- importDecl.Specs = append(importDecl.Specs, s)
- }
- importDecl.Specs = append(importDecl.Specs, blankImports...)
-
- // Synthesize main function.
- funcDecl := &ast.FuncDecl{
- Name: ast.NewIdent("main"),
- Type: &ast.FuncType{},
- Body: body,
- }
-
- // Synthesize file.
- return &ast.File{
- Name: ast.NewIdent("main"),
- Decls: []ast.Decl{importDecl, funcDecl},
- Comments: comments,
- }
-}
-
-// playExampleFile takes a whole file example and synthesizes a new *ast.File
-// such that the example is function main in package main.
-func playExampleFile(file *ast.File) *ast.File {
- // Strip copyright comment if present.
- comments := file.Comments
- if len(comments) > 0 && strings.HasPrefix(comments[0].Text(), "Copyright") {
- comments = comments[1:]
- }
-
- // Copy declaration slice, rewriting the ExampleX function to main.
- var decls []ast.Decl
- for _, d := range file.Decls {
- if f, ok := d.(*ast.FuncDecl); ok && isTest(f.Name.Name, "Example") {
- // Copy the FuncDecl, as it may be used elsewhere.
- newF := *f
- newF.Name = ast.NewIdent("main")
- newF.Body, comments = stripOutputComment(f.Body, comments)
- d = &newF
- }
- decls = append(decls, d)
- }
-
- // Copy the File, as it may be used elsewhere.
- f := *file
- f.Name = ast.NewIdent("main")
- f.Decls = decls
- f.Comments = comments
- return &f
-}
-
-// stripOutputComment finds and removes an "Output:" commment from body
-// and comments, and adjusts the body block's end position.
-func stripOutputComment(body *ast.BlockStmt, comments []*ast.CommentGroup) (*ast.BlockStmt, []*ast.CommentGroup) {
- // Do nothing if no "Output:" comment found.
- i, last := lastComment(body, comments)
- if last == nil || !outputPrefix.MatchString(last.Text()) {
- return body, comments
- }
-
- // Copy body and comments, as the originals may be used elsewhere.
- newBody := &ast.BlockStmt{
- Lbrace: body.Lbrace,
- List: body.List,
- Rbrace: last.Pos(),
- }
- newComments := make([]*ast.CommentGroup, len(comments)-1)
- copy(newComments, comments[:i])
- copy(newComments[i:], comments[i+1:])
- return newBody, newComments
-}
-
-// lastComment returns the last comment inside the provided block.
-func lastComment(b *ast.BlockStmt, c []*ast.CommentGroup) (i int, last *ast.CommentGroup) {
- pos, end := b.Pos(), b.End()
- for j, cg := range c {
- if cg.Pos() < pos {
- continue
- }
- if cg.End() > end {
- break
- }
- i, last = j, cg
- }
- return
-}