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path: root/libgo/go/cmd/go/internal/modfile/read.go
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-rw-r--r--libgo/go/cmd/go/internal/modfile/read.go869
1 files changed, 0 insertions, 869 deletions
diff --git a/libgo/go/cmd/go/internal/modfile/read.go b/libgo/go/cmd/go/internal/modfile/read.go
deleted file mode 100644
index 1d81ff1ab7a..00000000000
--- a/libgo/go/cmd/go/internal/modfile/read.go
+++ /dev/null
@@ -1,869 +0,0 @@
-// Copyright 2018 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-// Module file parser.
-// This is a simplified copy of Google's buildifier parser.
-
-package modfile
-
-import (
- "bytes"
- "fmt"
- "os"
- "strconv"
- "strings"
- "unicode"
- "unicode/utf8"
-)
-
-// A Position describes the position between two bytes of input.
-type Position struct {
- Line int // line in input (starting at 1)
- LineRune int // rune in line (starting at 1)
- Byte int // byte in input (starting at 0)
-}
-
-// add returns the position at the end of s, assuming it starts at p.
-func (p Position) add(s string) Position {
- p.Byte += len(s)
- if n := strings.Count(s, "\n"); n > 0 {
- p.Line += n
- s = s[strings.LastIndex(s, "\n")+1:]
- p.LineRune = 1
- }
- p.LineRune += utf8.RuneCountInString(s)
- return p
-}
-
-// An Expr represents an input element.
-type Expr interface {
- // Span returns the start and end position of the expression,
- // excluding leading or trailing comments.
- Span() (start, end Position)
-
- // Comment returns the comments attached to the expression.
- // This method would normally be named 'Comments' but that
- // would interfere with embedding a type of the same name.
- Comment() *Comments
-}
-
-// A Comment represents a single // comment.
-type Comment struct {
- Start Position
- Token string // without trailing newline
- Suffix bool // an end of line (not whole line) comment
-}
-
-// Comments collects the comments associated with an expression.
-type Comments struct {
- Before []Comment // whole-line comments before this expression
- Suffix []Comment // end-of-line comments after this expression
-
- // For top-level expressions only, After lists whole-line
- // comments following the expression.
- After []Comment
-}
-
-// Comment returns the receiver. This isn't useful by itself, but
-// a Comments struct is embedded into all the expression
-// implementation types, and this gives each of those a Comment
-// method to satisfy the Expr interface.
-func (c *Comments) Comment() *Comments {
- return c
-}
-
-// A FileSyntax represents an entire go.mod file.
-type FileSyntax struct {
- Name string // file path
- Comments
- Stmt []Expr
-}
-
-func (x *FileSyntax) Span() (start, end Position) {
- if len(x.Stmt) == 0 {
- return
- }
- start, _ = x.Stmt[0].Span()
- _, end = x.Stmt[len(x.Stmt)-1].Span()
- return start, end
-}
-
-func (x *FileSyntax) addLine(hint Expr, tokens ...string) *Line {
- if hint == nil {
- // If no hint given, add to the last statement of the given type.
- Loop:
- for i := len(x.Stmt) - 1; i >= 0; i-- {
- stmt := x.Stmt[i]
- switch stmt := stmt.(type) {
- case *Line:
- if stmt.Token != nil && stmt.Token[0] == tokens[0] {
- hint = stmt
- break Loop
- }
- case *LineBlock:
- if stmt.Token[0] == tokens[0] {
- hint = stmt
- break Loop
- }
- }
- }
- }
-
- if hint != nil {
- for i, stmt := range x.Stmt {
- switch stmt := stmt.(type) {
- case *Line:
- if stmt == hint {
- // Convert line to line block.
- stmt.InBlock = true
- block := &LineBlock{Token: stmt.Token[:1], Line: []*Line{stmt}}
- stmt.Token = stmt.Token[1:]
- x.Stmt[i] = block
- new := &Line{Token: tokens[1:], InBlock: true}
- block.Line = append(block.Line, new)
- return new
- }
- case *LineBlock:
- if stmt == hint {
- new := &Line{Token: tokens[1:], InBlock: true}
- stmt.Line = append(stmt.Line, new)
- return new
- }
- for j, line := range stmt.Line {
- if line == hint {
- // Add new line after hint.
- stmt.Line = append(stmt.Line, nil)
- copy(stmt.Line[j+2:], stmt.Line[j+1:])
- new := &Line{Token: tokens[1:], InBlock: true}
- stmt.Line[j+1] = new
- return new
- }
- }
- }
- }
- }
-
- new := &Line{Token: tokens}
- x.Stmt = append(x.Stmt, new)
- return new
-}
-
-func (x *FileSyntax) updateLine(line *Line, tokens ...string) {
- if line.InBlock {
- tokens = tokens[1:]
- }
- line.Token = tokens
-}
-
-func (x *FileSyntax) removeLine(line *Line) {
- line.Token = nil
-}
-
-// Cleanup cleans up the file syntax x after any edit operations.
-// To avoid quadratic behavior, removeLine marks the line as dead
-// by setting line.Token = nil but does not remove it from the slice
-// in which it appears. After edits have all been indicated,
-// calling Cleanup cleans out the dead lines.
-func (x *FileSyntax) Cleanup() {
- w := 0
- for _, stmt := range x.Stmt {
- switch stmt := stmt.(type) {
- case *Line:
- if stmt.Token == nil {
- continue
- }
- case *LineBlock:
- ww := 0
- for _, line := range stmt.Line {
- if line.Token != nil {
- stmt.Line[ww] = line
- ww++
- }
- }
- if ww == 0 {
- continue
- }
- if ww == 1 {
- // Collapse block into single line.
- line := &Line{
- Comments: Comments{
- Before: commentsAdd(stmt.Before, stmt.Line[0].Before),
- Suffix: commentsAdd(stmt.Line[0].Suffix, stmt.Suffix),
- After: commentsAdd(stmt.Line[0].After, stmt.After),
- },
- Token: stringsAdd(stmt.Token, stmt.Line[0].Token),
- }
- x.Stmt[w] = line
- w++
- continue
- }
- stmt.Line = stmt.Line[:ww]
- }
- x.Stmt[w] = stmt
- w++
- }
- x.Stmt = x.Stmt[:w]
-}
-
-func commentsAdd(x, y []Comment) []Comment {
- return append(x[:len(x):len(x)], y...)
-}
-
-func stringsAdd(x, y []string) []string {
- return append(x[:len(x):len(x)], y...)
-}
-
-// A CommentBlock represents a top-level block of comments separate
-// from any rule.
-type CommentBlock struct {
- Comments
- Start Position
-}
-
-func (x *CommentBlock) Span() (start, end Position) {
- return x.Start, x.Start
-}
-
-// A Line is a single line of tokens.
-type Line struct {
- Comments
- Start Position
- Token []string
- InBlock bool
- End Position
-}
-
-func (x *Line) Span() (start, end Position) {
- return x.Start, x.End
-}
-
-// A LineBlock is a factored block of lines, like
-//
-// require (
-// "x"
-// "y"
-// )
-//
-type LineBlock struct {
- Comments
- Start Position
- LParen LParen
- Token []string
- Line []*Line
- RParen RParen
-}
-
-func (x *LineBlock) Span() (start, end Position) {
- return x.Start, x.RParen.Pos.add(")")
-}
-
-// An LParen represents the beginning of a parenthesized line block.
-// It is a place to store suffix comments.
-type LParen struct {
- Comments
- Pos Position
-}
-
-func (x *LParen) Span() (start, end Position) {
- return x.Pos, x.Pos.add(")")
-}
-
-// An RParen represents the end of a parenthesized line block.
-// It is a place to store whole-line (before) comments.
-type RParen struct {
- Comments
- Pos Position
-}
-
-func (x *RParen) Span() (start, end Position) {
- return x.Pos, x.Pos.add(")")
-}
-
-// An input represents a single input file being parsed.
-type input struct {
- // Lexing state.
- filename string // name of input file, for errors
- complete []byte // entire input
- remaining []byte // remaining input
- token []byte // token being scanned
- lastToken string // most recently returned token, for error messages
- pos Position // current input position
- comments []Comment // accumulated comments
- endRule int // position of end of current rule
-
- // Parser state.
- file *FileSyntax // returned top-level syntax tree
- parseError error // error encountered during parsing
-
- // Comment assignment state.
- pre []Expr // all expressions, in preorder traversal
- post []Expr // all expressions, in postorder traversal
-}
-
-func newInput(filename string, data []byte) *input {
- return &input{
- filename: filename,
- complete: data,
- remaining: data,
- pos: Position{Line: 1, LineRune: 1, Byte: 0},
- }
-}
-
-// parse parses the input file.
-func parse(file string, data []byte) (f *FileSyntax, err error) {
- in := newInput(file, data)
- // The parser panics for both routine errors like syntax errors
- // and for programmer bugs like array index errors.
- // Turn both into error returns. Catching bug panics is
- // especially important when processing many files.
- defer func() {
- if e := recover(); e != nil {
- if e == in.parseError {
- err = in.parseError
- } else {
- err = fmt.Errorf("%s:%d:%d: internal error: %v", in.filename, in.pos.Line, in.pos.LineRune, e)
- }
- }
- }()
-
- // Invoke the parser.
- in.parseFile()
- if in.parseError != nil {
- return nil, in.parseError
- }
- in.file.Name = in.filename
-
- // Assign comments to nearby syntax.
- in.assignComments()
-
- return in.file, nil
-}
-
-// Error is called to report an error.
-// The reason s is often "syntax error".
-// Error does not return: it panics.
-func (in *input) Error(s string) {
- if s == "syntax error" && in.lastToken != "" {
- s += " near " + in.lastToken
- }
- in.parseError = fmt.Errorf("%s:%d:%d: %v", in.filename, in.pos.Line, in.pos.LineRune, s)
- panic(in.parseError)
-}
-
-// eof reports whether the input has reached end of file.
-func (in *input) eof() bool {
- return len(in.remaining) == 0
-}
-
-// peekRune returns the next rune in the input without consuming it.
-func (in *input) peekRune() int {
- if len(in.remaining) == 0 {
- return 0
- }
- r, _ := utf8.DecodeRune(in.remaining)
- return int(r)
-}
-
-// peekPrefix reports whether the remaining input begins with the given prefix.
-func (in *input) peekPrefix(prefix string) bool {
- // This is like bytes.HasPrefix(in.remaining, []byte(prefix))
- // but without the allocation of the []byte copy of prefix.
- for i := 0; i < len(prefix); i++ {
- if i >= len(in.remaining) || in.remaining[i] != prefix[i] {
- return false
- }
- }
- return true
-}
-
-// readRune consumes and returns the next rune in the input.
-func (in *input) readRune() int {
- if len(in.remaining) == 0 {
- in.Error("internal lexer error: readRune at EOF")
- }
- r, size := utf8.DecodeRune(in.remaining)
- in.remaining = in.remaining[size:]
- if r == '\n' {
- in.pos.Line++
- in.pos.LineRune = 1
- } else {
- in.pos.LineRune++
- }
- in.pos.Byte += size
- return int(r)
-}
-
-type symType struct {
- pos Position
- endPos Position
- text string
-}
-
-// startToken marks the beginning of the next input token.
-// It must be followed by a call to endToken, once the token has
-// been consumed using readRune.
-func (in *input) startToken(sym *symType) {
- in.token = in.remaining
- sym.text = ""
- sym.pos = in.pos
-}
-
-// endToken marks the end of an input token.
-// It records the actual token string in sym.text if the caller
-// has not done that already.
-func (in *input) endToken(sym *symType) {
- if sym.text == "" {
- tok := string(in.token[:len(in.token)-len(in.remaining)])
- sym.text = tok
- in.lastToken = sym.text
- }
- sym.endPos = in.pos
-}
-
-// lex is called from the parser to obtain the next input token.
-// It returns the token value (either a rune like '+' or a symbolic token _FOR)
-// and sets val to the data associated with the token.
-// For all our input tokens, the associated data is
-// val.Pos (the position where the token begins)
-// and val.Token (the input string corresponding to the token).
-func (in *input) lex(sym *symType) int {
- // Skip past spaces, stopping at non-space or EOF.
- countNL := 0 // number of newlines we've skipped past
- for !in.eof() {
- // Skip over spaces. Count newlines so we can give the parser
- // information about where top-level blank lines are,
- // for top-level comment assignment.
- c := in.peekRune()
- if c == ' ' || c == '\t' || c == '\r' {
- in.readRune()
- continue
- }
-
- // Comment runs to end of line.
- if in.peekPrefix("//") {
- in.startToken(sym)
-
- // Is this comment the only thing on its line?
- // Find the last \n before this // and see if it's all
- // spaces from there to here.
- i := bytes.LastIndex(in.complete[:in.pos.Byte], []byte("\n"))
- suffix := len(bytes.TrimSpace(in.complete[i+1:in.pos.Byte])) > 0
- in.readRune()
- in.readRune()
-
- // Consume comment.
- for len(in.remaining) > 0 && in.readRune() != '\n' {
- }
- in.endToken(sym)
-
- sym.text = strings.TrimRight(sym.text, "\n")
- in.lastToken = "comment"
-
- // If we are at top level (not in a statement), hand the comment to
- // the parser as a _COMMENT token. The grammar is written
- // to handle top-level comments itself.
- if !suffix {
- // Not in a statement. Tell parser about top-level comment.
- return _COMMENT
- }
-
- // Otherwise, save comment for later attachment to syntax tree.
- if countNL > 1 {
- in.comments = append(in.comments, Comment{sym.pos, "", false})
- }
- in.comments = append(in.comments, Comment{sym.pos, sym.text, suffix})
- countNL = 1
- return _EOL
- }
-
- if in.peekPrefix("/*") {
- in.Error(fmt.Sprintf("mod files must use // comments (not /* */ comments)"))
- }
-
- // Found non-space non-comment.
- break
- }
-
- // Found the beginning of the next token.
- in.startToken(sym)
- defer in.endToken(sym)
-
- // End of file.
- if in.eof() {
- in.lastToken = "EOF"
- return _EOF
- }
-
- // Punctuation tokens.
- switch c := in.peekRune(); c {
- case '\n':
- in.readRune()
- return c
-
- case '(':
- in.readRune()
- return c
-
- case ')':
- in.readRune()
- return c
-
- case '"', '`': // quoted string
- quote := c
- in.readRune()
- for {
- if in.eof() {
- in.pos = sym.pos
- in.Error("unexpected EOF in string")
- }
- if in.peekRune() == '\n' {
- in.Error("unexpected newline in string")
- }
- c := in.readRune()
- if c == quote {
- break
- }
- if c == '\\' && quote != '`' {
- if in.eof() {
- in.pos = sym.pos
- in.Error("unexpected EOF in string")
- }
- in.readRune()
- }
- }
- in.endToken(sym)
- return _STRING
- }
-
- // Checked all punctuation. Must be identifier token.
- if c := in.peekRune(); !isIdent(c) {
- in.Error(fmt.Sprintf("unexpected input character %#q", c))
- }
-
- // Scan over identifier.
- for isIdent(in.peekRune()) {
- if in.peekPrefix("//") {
- break
- }
- if in.peekPrefix("/*") {
- in.Error(fmt.Sprintf("mod files must use // comments (not /* */ comments)"))
- }
- in.readRune()
- }
- return _IDENT
-}
-
-// isIdent reports whether c is an identifier rune.
-// We treat nearly all runes as identifier runes.
-func isIdent(c int) bool {
- return c != 0 && !unicode.IsSpace(rune(c))
-}
-
-// Comment assignment.
-// We build two lists of all subexpressions, preorder and postorder.
-// The preorder list is ordered by start location, with outer expressions first.
-// The postorder list is ordered by end location, with outer expressions last.
-// We use the preorder list to assign each whole-line comment to the syntax
-// immediately following it, and we use the postorder list to assign each
-// end-of-line comment to the syntax immediately preceding it.
-
-// order walks the expression adding it and its subexpressions to the
-// preorder and postorder lists.
-func (in *input) order(x Expr) {
- if x != nil {
- in.pre = append(in.pre, x)
- }
- switch x := x.(type) {
- default:
- panic(fmt.Errorf("order: unexpected type %T", x))
- case nil:
- // nothing
- case *LParen, *RParen:
- // nothing
- case *CommentBlock:
- // nothing
- case *Line:
- // nothing
- case *FileSyntax:
- for _, stmt := range x.Stmt {
- in.order(stmt)
- }
- case *LineBlock:
- in.order(&x.LParen)
- for _, l := range x.Line {
- in.order(l)
- }
- in.order(&x.RParen)
- }
- if x != nil {
- in.post = append(in.post, x)
- }
-}
-
-// assignComments attaches comments to nearby syntax.
-func (in *input) assignComments() {
- const debug = false
-
- // Generate preorder and postorder lists.
- in.order(in.file)
-
- // Split into whole-line comments and suffix comments.
- var line, suffix []Comment
- for _, com := range in.comments {
- if com.Suffix {
- suffix = append(suffix, com)
- } else {
- line = append(line, com)
- }
- }
-
- if debug {
- for _, c := range line {
- fmt.Fprintf(os.Stderr, "LINE %q :%d:%d #%d\n", c.Token, c.Start.Line, c.Start.LineRune, c.Start.Byte)
- }
- }
-
- // Assign line comments to syntax immediately following.
- for _, x := range in.pre {
- start, _ := x.Span()
- if debug {
- fmt.Printf("pre %T :%d:%d #%d\n", x, start.Line, start.LineRune, start.Byte)
- }
- xcom := x.Comment()
- for len(line) > 0 && start.Byte >= line[0].Start.Byte {
- if debug {
- fmt.Fprintf(os.Stderr, "ASSIGN LINE %q #%d\n", line[0].Token, line[0].Start.Byte)
- }
- xcom.Before = append(xcom.Before, line[0])
- line = line[1:]
- }
- }
-
- // Remaining line comments go at end of file.
- in.file.After = append(in.file.After, line...)
-
- if debug {
- for _, c := range suffix {
- fmt.Fprintf(os.Stderr, "SUFFIX %q :%d:%d #%d\n", c.Token, c.Start.Line, c.Start.LineRune, c.Start.Byte)
- }
- }
-
- // Assign suffix comments to syntax immediately before.
- for i := len(in.post) - 1; i >= 0; i-- {
- x := in.post[i]
-
- start, end := x.Span()
- if debug {
- fmt.Printf("post %T :%d:%d #%d :%d:%d #%d\n", x, start.Line, start.LineRune, start.Byte, end.Line, end.LineRune, end.Byte)
- }
-
- // Do not assign suffix comments to end of line block or whole file.
- // Instead assign them to the last element inside.
- switch x.(type) {
- case *FileSyntax:
- continue
- }
-
- // Do not assign suffix comments to something that starts
- // on an earlier line, so that in
- //
- // x ( y
- // z ) // comment
- //
- // we assign the comment to z and not to x ( ... ).
- if start.Line != end.Line {
- continue
- }
- xcom := x.Comment()
- for len(suffix) > 0 && end.Byte <= suffix[len(suffix)-1].Start.Byte {
- if debug {
- fmt.Fprintf(os.Stderr, "ASSIGN SUFFIX %q #%d\n", suffix[len(suffix)-1].Token, suffix[len(suffix)-1].Start.Byte)
- }
- xcom.Suffix = append(xcom.Suffix, suffix[len(suffix)-1])
- suffix = suffix[:len(suffix)-1]
- }
- }
-
- // We assigned suffix comments in reverse.
- // If multiple suffix comments were appended to the same
- // expression node, they are now in reverse. Fix that.
- for _, x := range in.post {
- reverseComments(x.Comment().Suffix)
- }
-
- // Remaining suffix comments go at beginning of file.
- in.file.Before = append(in.file.Before, suffix...)
-}
-
-// reverseComments reverses the []Comment list.
-func reverseComments(list []Comment) {
- for i, j := 0, len(list)-1; i < j; i, j = i+1, j-1 {
- list[i], list[j] = list[j], list[i]
- }
-}
-
-func (in *input) parseFile() {
- in.file = new(FileSyntax)
- var sym symType
- var cb *CommentBlock
- for {
- tok := in.lex(&sym)
- switch tok {
- case '\n':
- if cb != nil {
- in.file.Stmt = append(in.file.Stmt, cb)
- cb = nil
- }
- case _COMMENT:
- if cb == nil {
- cb = &CommentBlock{Start: sym.pos}
- }
- com := cb.Comment()
- com.Before = append(com.Before, Comment{Start: sym.pos, Token: sym.text})
- case _EOF:
- if cb != nil {
- in.file.Stmt = append(in.file.Stmt, cb)
- }
- return
- default:
- in.parseStmt(&sym)
- if cb != nil {
- in.file.Stmt[len(in.file.Stmt)-1].Comment().Before = cb.Before
- cb = nil
- }
- }
- }
-}
-
-func (in *input) parseStmt(sym *symType) {
- start := sym.pos
- end := sym.endPos
- token := []string{sym.text}
- for {
- tok := in.lex(sym)
- switch tok {
- case '\n', _EOF, _EOL:
- in.file.Stmt = append(in.file.Stmt, &Line{
- Start: start,
- Token: token,
- End: end,
- })
- return
- case '(':
- in.file.Stmt = append(in.file.Stmt, in.parseLineBlock(start, token, sym))
- return
- default:
- token = append(token, sym.text)
- end = sym.endPos
- }
- }
-}
-
-func (in *input) parseLineBlock(start Position, token []string, sym *symType) *LineBlock {
- x := &LineBlock{
- Start: start,
- Token: token,
- LParen: LParen{Pos: sym.pos},
- }
- var comments []Comment
- for {
- tok := in.lex(sym)
- switch tok {
- case _EOL:
- // ignore
- case '\n':
- if len(comments) == 0 && len(x.Line) > 0 || len(comments) > 0 && comments[len(comments)-1].Token != "" {
- comments = append(comments, Comment{})
- }
- case _COMMENT:
- comments = append(comments, Comment{Start: sym.pos, Token: sym.text})
- case _EOF:
- in.Error(fmt.Sprintf("syntax error (unterminated block started at %s:%d:%d)", in.filename, x.Start.Line, x.Start.LineRune))
- case ')':
- x.RParen.Before = comments
- x.RParen.Pos = sym.pos
- tok = in.lex(sym)
- if tok != '\n' && tok != _EOF && tok != _EOL {
- in.Error("syntax error (expected newline after closing paren)")
- }
- return x
- default:
- l := in.parseLine(sym)
- x.Line = append(x.Line, l)
- l.Comment().Before = comments
- comments = nil
- }
- }
-}
-
-func (in *input) parseLine(sym *symType) *Line {
- start := sym.pos
- end := sym.endPos
- token := []string{sym.text}
- for {
- tok := in.lex(sym)
- switch tok {
- case '\n', _EOF, _EOL:
- return &Line{
- Start: start,
- Token: token,
- End: end,
- InBlock: true,
- }
- default:
- token = append(token, sym.text)
- end = sym.endPos
- }
- }
-}
-
-const (
- _EOF = -(1 + iota)
- _EOL
- _IDENT
- _STRING
- _COMMENT
-)
-
-var (
- slashSlash = []byte("//")
- moduleStr = []byte("module")
-)
-
-// ModulePath returns the module path from the gomod file text.
-// If it cannot find a module path, it returns an empty string.
-// It is tolerant of unrelated problems in the go.mod file.
-func ModulePath(mod []byte) string {
- for len(mod) > 0 {
- line := mod
- mod = nil
- if i := bytes.IndexByte(line, '\n'); i >= 0 {
- line, mod = line[:i], line[i+1:]
- }
- if i := bytes.Index(line, slashSlash); i >= 0 {
- line = line[:i]
- }
- line = bytes.TrimSpace(line)
- if !bytes.HasPrefix(line, moduleStr) {
- continue
- }
- line = line[len(moduleStr):]
- n := len(line)
- line = bytes.TrimSpace(line)
- if len(line) == n || len(line) == 0 {
- continue
- }
-
- if line[0] == '"' || line[0] == '`' {
- p, err := strconv.Unquote(string(line))
- if err != nil {
- return "" // malformed quoted string or multiline module path
- }
- return p
- }
-
- return string(line)
- }
- return "" // missing module path
-}
generated by cgit v1.2.3 (git 2.25.1) at 2024-06-04 16:49:28 +0000