959 lines
23 KiB
Go
959 lines
23 KiB
Go
// Copyright 2018 The Go Authors. All rights reserved.
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// Use of this source code is governed by a BSD-style
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// license that can be found in the LICENSE file.
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package modfile
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import (
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"bytes"
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"errors"
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"fmt"
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"os"
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"strconv"
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"strings"
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"unicode"
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"unicode/utf8"
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)
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// A Position describes an arbitrary source position in a file, including the
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// file, line, column, and byte offset.
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type Position struct {
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Line int // line in input (starting at 1)
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LineRune int // rune in line (starting at 1)
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Byte int // byte in input (starting at 0)
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}
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// add returns the position at the end of s, assuming it starts at p.
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func (p Position) add(s string) Position {
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p.Byte += len(s)
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if n := strings.Count(s, "\n"); n > 0 {
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p.Line += n
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s = s[strings.LastIndex(s, "\n")+1:]
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p.LineRune = 1
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}
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p.LineRune += utf8.RuneCountInString(s)
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return p
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}
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// An Expr represents an input element.
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type Expr interface {
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// Span returns the start and end position of the expression,
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// excluding leading or trailing comments.
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Span() (start, end Position)
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// Comment returns the comments attached to the expression.
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// This method would normally be named 'Comments' but that
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// would interfere with embedding a type of the same name.
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Comment() *Comments
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}
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// A Comment represents a single // comment.
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type Comment struct {
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Start Position
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Token string // without trailing newline
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Suffix bool // an end of line (not whole line) comment
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}
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// Comments collects the comments associated with an expression.
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type Comments struct {
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Before []Comment // whole-line comments before this expression
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Suffix []Comment // end-of-line comments after this expression
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// For top-level expressions only, After lists whole-line
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// comments following the expression.
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After []Comment
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}
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// Comment returns the receiver. This isn't useful by itself, but
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// a Comments struct is embedded into all the expression
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// implementation types, and this gives each of those a Comment
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// method to satisfy the Expr interface.
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func (c *Comments) Comment() *Comments {
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return c
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}
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// A FileSyntax represents an entire go.mod file.
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type FileSyntax struct {
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Name string // file path
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Comments
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Stmt []Expr
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}
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func (x *FileSyntax) Span() (start, end Position) {
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if len(x.Stmt) == 0 {
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return
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}
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start, _ = x.Stmt[0].Span()
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_, end = x.Stmt[len(x.Stmt)-1].Span()
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return start, end
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}
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// addLine adds a line containing the given tokens to the file.
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//
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// If the first token of the hint matches the first token of the
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// line, the new line is added at the end of the block containing hint,
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// extracting hint into a new block if it is not yet in one.
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//
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// If the hint is non-nil buts its first token does not match,
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// the new line is added after the block containing hint
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// (or hint itself, if not in a block).
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//
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// If no hint is provided, addLine appends the line to the end of
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// the last block with a matching first token,
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// or to the end of the file if no such block exists.
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func (x *FileSyntax) addLine(hint Expr, tokens ...string) *Line {
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if hint == nil {
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// If no hint given, add to the last statement of the given type.
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Loop:
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for i := len(x.Stmt) - 1; i >= 0; i-- {
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stmt := x.Stmt[i]
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switch stmt := stmt.(type) {
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case *Line:
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if stmt.Token != nil && stmt.Token[0] == tokens[0] {
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hint = stmt
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break Loop
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}
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case *LineBlock:
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if stmt.Token[0] == tokens[0] {
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hint = stmt
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break Loop
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}
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}
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}
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}
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newLineAfter := func(i int) *Line {
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new := &Line{Token: tokens}
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if i == len(x.Stmt) {
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x.Stmt = append(x.Stmt, new)
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} else {
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x.Stmt = append(x.Stmt, nil)
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copy(x.Stmt[i+2:], x.Stmt[i+1:])
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x.Stmt[i+1] = new
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}
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return new
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}
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if hint != nil {
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for i, stmt := range x.Stmt {
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switch stmt := stmt.(type) {
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case *Line:
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if stmt == hint {
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if stmt.Token == nil || stmt.Token[0] != tokens[0] {
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return newLineAfter(i)
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}
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// Convert line to line block.
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stmt.InBlock = true
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block := &LineBlock{Token: stmt.Token[:1], Line: []*Line{stmt}}
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stmt.Token = stmt.Token[1:]
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x.Stmt[i] = block
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new := &Line{Token: tokens[1:], InBlock: true}
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block.Line = append(block.Line, new)
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return new
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}
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case *LineBlock:
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if stmt == hint {
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if stmt.Token[0] != tokens[0] {
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return newLineAfter(i)
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}
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new := &Line{Token: tokens[1:], InBlock: true}
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stmt.Line = append(stmt.Line, new)
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return new
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}
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for j, line := range stmt.Line {
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if line == hint {
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if stmt.Token[0] != tokens[0] {
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return newLineAfter(i)
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}
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// Add new line after hint within the block.
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stmt.Line = append(stmt.Line, nil)
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copy(stmt.Line[j+2:], stmt.Line[j+1:])
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new := &Line{Token: tokens[1:], InBlock: true}
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stmt.Line[j+1] = new
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return new
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}
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}
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}
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}
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}
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new := &Line{Token: tokens}
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x.Stmt = append(x.Stmt, new)
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return new
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}
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func (x *FileSyntax) updateLine(line *Line, tokens ...string) {
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if line.InBlock {
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tokens = tokens[1:]
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}
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line.Token = tokens
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}
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// markRemoved modifies line so that it (and its end-of-line comment, if any)
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// will be dropped by (*FileSyntax).Cleanup.
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func (line *Line) markRemoved() {
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line.Token = nil
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line.Comments.Suffix = nil
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}
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// Cleanup cleans up the file syntax x after any edit operations.
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// To avoid quadratic behavior, (*Line).markRemoved marks the line as dead
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// by setting line.Token = nil but does not remove it from the slice
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// in which it appears. After edits have all been indicated,
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// calling Cleanup cleans out the dead lines.
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func (x *FileSyntax) Cleanup() {
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w := 0
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for _, stmt := range x.Stmt {
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switch stmt := stmt.(type) {
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case *Line:
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if stmt.Token == nil {
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continue
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}
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case *LineBlock:
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ww := 0
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for _, line := range stmt.Line {
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if line.Token != nil {
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stmt.Line[ww] = line
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ww++
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}
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}
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if ww == 0 {
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continue
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}
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if ww == 1 {
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// Collapse block into single line.
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line := &Line{
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Comments: Comments{
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Before: commentsAdd(stmt.Before, stmt.Line[0].Before),
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Suffix: commentsAdd(stmt.Line[0].Suffix, stmt.Suffix),
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After: commentsAdd(stmt.Line[0].After, stmt.After),
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},
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Token: stringsAdd(stmt.Token, stmt.Line[0].Token),
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}
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x.Stmt[w] = line
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w++
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continue
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}
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stmt.Line = stmt.Line[:ww]
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}
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x.Stmt[w] = stmt
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w++
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}
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x.Stmt = x.Stmt[:w]
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}
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func commentsAdd(x, y []Comment) []Comment {
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return append(x[:len(x):len(x)], y...)
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}
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func stringsAdd(x, y []string) []string {
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return append(x[:len(x):len(x)], y...)
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}
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// A CommentBlock represents a top-level block of comments separate
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// from any rule.
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type CommentBlock struct {
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Comments
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Start Position
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}
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func (x *CommentBlock) Span() (start, end Position) {
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return x.Start, x.Start
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}
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// A Line is a single line of tokens.
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type Line struct {
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Comments
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Start Position
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Token []string
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InBlock bool
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End Position
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}
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func (x *Line) Span() (start, end Position) {
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return x.Start, x.End
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}
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// A LineBlock is a factored block of lines, like
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//
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// require (
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// "x"
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// "y"
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// )
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type LineBlock struct {
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Comments
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Start Position
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LParen LParen
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Token []string
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Line []*Line
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RParen RParen
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}
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func (x *LineBlock) Span() (start, end Position) {
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return x.Start, x.RParen.Pos.add(")")
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}
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// An LParen represents the beginning of a parenthesized line block.
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// It is a place to store suffix comments.
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type LParen struct {
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Comments
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Pos Position
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}
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func (x *LParen) Span() (start, end Position) {
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return x.Pos, x.Pos.add(")")
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}
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// An RParen represents the end of a parenthesized line block.
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// It is a place to store whole-line (before) comments.
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type RParen struct {
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Comments
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Pos Position
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}
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func (x *RParen) Span() (start, end Position) {
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return x.Pos, x.Pos.add(")")
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}
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// An input represents a single input file being parsed.
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type input struct {
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// Lexing state.
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filename string // name of input file, for errors
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complete []byte // entire input
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remaining []byte // remaining input
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tokenStart []byte // token being scanned to end of input
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token token // next token to be returned by lex, peek
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pos Position // current input position
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comments []Comment // accumulated comments
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// Parser state.
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file *FileSyntax // returned top-level syntax tree
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parseErrors ErrorList // errors encountered during parsing
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// Comment assignment state.
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pre []Expr // all expressions, in preorder traversal
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post []Expr // all expressions, in postorder traversal
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}
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func newInput(filename string, data []byte) *input {
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return &input{
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filename: filename,
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complete: data,
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remaining: data,
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pos: Position{Line: 1, LineRune: 1, Byte: 0},
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}
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}
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// parse parses the input file.
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func parse(file string, data []byte) (f *FileSyntax, err error) {
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// The parser panics for both routine errors like syntax errors
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// and for programmer bugs like array index errors.
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// Turn both into error returns. Catching bug panics is
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// especially important when processing many files.
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in := newInput(file, data)
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defer func() {
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if e := recover(); e != nil && e != &in.parseErrors {
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in.parseErrors = append(in.parseErrors, Error{
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Filename: in.filename,
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Pos: in.pos,
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Err: fmt.Errorf("internal error: %v", e),
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})
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}
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if err == nil && len(in.parseErrors) > 0 {
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err = in.parseErrors
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}
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}()
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// Prime the lexer by reading in the first token. It will be available
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// in the next peek() or lex() call.
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in.readToken()
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// Invoke the parser.
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in.parseFile()
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if len(in.parseErrors) > 0 {
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return nil, in.parseErrors
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}
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in.file.Name = in.filename
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// Assign comments to nearby syntax.
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in.assignComments()
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return in.file, nil
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}
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// Error is called to report an error.
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// Error does not return: it panics.
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func (in *input) Error(s string) {
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in.parseErrors = append(in.parseErrors, Error{
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Filename: in.filename,
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Pos: in.pos,
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Err: errors.New(s),
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})
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panic(&in.parseErrors)
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}
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// eof reports whether the input has reached end of file.
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func (in *input) eof() bool {
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return len(in.remaining) == 0
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}
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// peekRune returns the next rune in the input without consuming it.
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func (in *input) peekRune() int {
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if len(in.remaining) == 0 {
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return 0
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}
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r, _ := utf8.DecodeRune(in.remaining)
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return int(r)
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}
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// peekPrefix reports whether the remaining input begins with the given prefix.
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func (in *input) peekPrefix(prefix string) bool {
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// This is like bytes.HasPrefix(in.remaining, []byte(prefix))
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// but without the allocation of the []byte copy of prefix.
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for i := 0; i < len(prefix); i++ {
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if i >= len(in.remaining) || in.remaining[i] != prefix[i] {
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return false
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}
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}
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return true
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}
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// readRune consumes and returns the next rune in the input.
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func (in *input) readRune() int {
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if len(in.remaining) == 0 {
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in.Error("internal lexer error: readRune at EOF")
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}
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r, size := utf8.DecodeRune(in.remaining)
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in.remaining = in.remaining[size:]
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if r == '\n' {
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in.pos.Line++
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in.pos.LineRune = 1
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} else {
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in.pos.LineRune++
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}
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in.pos.Byte += size
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return int(r)
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}
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type token struct {
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kind tokenKind
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pos Position
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endPos Position
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text string
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}
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type tokenKind int
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const (
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_EOF tokenKind = -(iota + 1)
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_EOLCOMMENT
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_IDENT
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_STRING
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_COMMENT
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// newlines and punctuation tokens are allowed as ASCII codes.
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)
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func (k tokenKind) isComment() bool {
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return k == _COMMENT || k == _EOLCOMMENT
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}
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// isEOL returns whether a token terminates a line.
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func (k tokenKind) isEOL() bool {
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return k == _EOF || k == _EOLCOMMENT || k == '\n'
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}
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// startToken marks the beginning of the next input token.
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// It must be followed by a call to endToken, once the token's text has
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// been consumed using readRune.
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func (in *input) startToken() {
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in.tokenStart = in.remaining
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in.token.text = ""
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in.token.pos = in.pos
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}
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// endToken marks the end of an input token.
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// It records the actual token string in tok.text.
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// A single trailing newline (LF or CRLF) will be removed from comment tokens.
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func (in *input) endToken(kind tokenKind) {
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in.token.kind = kind
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text := string(in.tokenStart[:len(in.tokenStart)-len(in.remaining)])
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if kind.isComment() {
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if strings.HasSuffix(text, "\r\n") {
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text = text[:len(text)-2]
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} else {
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text = strings.TrimSuffix(text, "\n")
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}
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}
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in.token.text = text
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in.token.endPos = in.pos
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}
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// peek returns the kind of the next token returned by lex.
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func (in *input) peek() tokenKind {
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return in.token.kind
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}
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// lex is called from the parser to obtain the next input token.
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func (in *input) lex() token {
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tok := in.token
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in.readToken()
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return tok
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}
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// readToken lexes the next token from the text and stores it in in.token.
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func (in *input) readToken() {
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// Skip past spaces, stopping at non-space or EOF.
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for !in.eof() {
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c := in.peekRune()
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if c == ' ' || c == '\t' || c == '\r' {
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in.readRune()
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continue
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}
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// Comment runs to end of line.
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if in.peekPrefix("//") {
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in.startToken()
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// Is this comment the only thing on its line?
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// Find the last \n before this // and see if it's all
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// spaces from there to here.
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i := bytes.LastIndex(in.complete[:in.pos.Byte], []byte("\n"))
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suffix := len(bytes.TrimSpace(in.complete[i+1:in.pos.Byte])) > 0
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in.readRune()
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in.readRune()
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// Consume comment.
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for len(in.remaining) > 0 && in.readRune() != '\n' {
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}
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// If we are at top level (not in a statement), hand the comment to
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// the parser as a _COMMENT token. The grammar is written
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// to handle top-level comments itself.
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if !suffix {
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in.endToken(_COMMENT)
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return
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}
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// Otherwise, save comment for later attachment to syntax tree.
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in.endToken(_EOLCOMMENT)
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in.comments = append(in.comments, Comment{in.token.pos, in.token.text, suffix})
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return
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}
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if in.peekPrefix("/*") {
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in.Error("mod files must use // comments (not /* */ comments)")
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}
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// Found non-space non-comment.
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break
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}
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// Found the beginning of the next token.
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in.startToken()
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// End of file.
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if in.eof() {
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in.endToken(_EOF)
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return
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|
}
|
|
|
|
// Punctuation tokens.
|
|
switch c := in.peekRune(); c {
|
|
case '\n', '(', ')', '[', ']', '{', '}', ',':
|
|
in.readRune()
|
|
in.endToken(tokenKind(c))
|
|
return
|
|
|
|
case '"', '`': // quoted string
|
|
quote := c
|
|
in.readRune()
|
|
for {
|
|
if in.eof() {
|
|
in.pos = in.token.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 = in.token.pos
|
|
in.Error("unexpected EOF in string")
|
|
}
|
|
in.readRune()
|
|
}
|
|
}
|
|
in.endToken(_STRING)
|
|
return
|
|
}
|
|
|
|
// 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("mod files must use // comments (not /* */ comments)")
|
|
}
|
|
in.readRune()
|
|
}
|
|
in.endToken(_IDENT)
|
|
}
|
|
|
|
// isIdent reports whether c is an identifier rune.
|
|
// We treat most printable runes as identifier runes, except for a handful of
|
|
// ASCII punctuation characters.
|
|
func isIdent(c int) bool {
|
|
switch r := rune(c); r {
|
|
case ' ', '(', ')', '[', ']', '{', '}', ',':
|
|
return false
|
|
default:
|
|
return !unicode.IsSpace(r) && unicode.IsPrint(r)
|
|
}
|
|
}
|
|
|
|
// 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.Fprintf(os.Stderr, "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.Fprintf(os.Stderr, "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 cb *CommentBlock
|
|
for {
|
|
switch in.peek() {
|
|
case '\n':
|
|
in.lex()
|
|
if cb != nil {
|
|
in.file.Stmt = append(in.file.Stmt, cb)
|
|
cb = nil
|
|
}
|
|
case _COMMENT:
|
|
tok := in.lex()
|
|
if cb == nil {
|
|
cb = &CommentBlock{Start: tok.pos}
|
|
}
|
|
com := cb.Comment()
|
|
com.Before = append(com.Before, Comment{Start: tok.pos, Token: tok.text})
|
|
case _EOF:
|
|
if cb != nil {
|
|
in.file.Stmt = append(in.file.Stmt, cb)
|
|
}
|
|
return
|
|
default:
|
|
in.parseStmt()
|
|
if cb != nil {
|
|
in.file.Stmt[len(in.file.Stmt)-1].Comment().Before = cb.Before
|
|
cb = nil
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
func (in *input) parseStmt() {
|
|
tok := in.lex()
|
|
start := tok.pos
|
|
end := tok.endPos
|
|
tokens := []string{tok.text}
|
|
for {
|
|
tok := in.lex()
|
|
switch {
|
|
case tok.kind.isEOL():
|
|
in.file.Stmt = append(in.file.Stmt, &Line{
|
|
Start: start,
|
|
Token: tokens,
|
|
End: end,
|
|
})
|
|
return
|
|
|
|
case tok.kind == '(':
|
|
if next := in.peek(); next.isEOL() {
|
|
// Start of block: no more tokens on this line.
|
|
in.file.Stmt = append(in.file.Stmt, in.parseLineBlock(start, tokens, tok))
|
|
return
|
|
} else if next == ')' {
|
|
rparen := in.lex()
|
|
if in.peek().isEOL() {
|
|
// Empty block.
|
|
in.lex()
|
|
in.file.Stmt = append(in.file.Stmt, &LineBlock{
|
|
Start: start,
|
|
Token: tokens,
|
|
LParen: LParen{Pos: tok.pos},
|
|
RParen: RParen{Pos: rparen.pos},
|
|
})
|
|
return
|
|
}
|
|
// '( )' in the middle of the line, not a block.
|
|
tokens = append(tokens, tok.text, rparen.text)
|
|
} else {
|
|
// '(' in the middle of the line, not a block.
|
|
tokens = append(tokens, tok.text)
|
|
}
|
|
|
|
default:
|
|
tokens = append(tokens, tok.text)
|
|
end = tok.endPos
|
|
}
|
|
}
|
|
}
|
|
|
|
func (in *input) parseLineBlock(start Position, token []string, lparen token) *LineBlock {
|
|
x := &LineBlock{
|
|
Start: start,
|
|
Token: token,
|
|
LParen: LParen{Pos: lparen.pos},
|
|
}
|
|
var comments []Comment
|
|
for {
|
|
switch in.peek() {
|
|
case _EOLCOMMENT:
|
|
// Suffix comment, will be attached later by assignComments.
|
|
in.lex()
|
|
case '\n':
|
|
// Blank line. Add an empty comment to preserve it.
|
|
in.lex()
|
|
if len(comments) == 0 && len(x.Line) > 0 || len(comments) > 0 && comments[len(comments)-1].Token != "" {
|
|
comments = append(comments, Comment{})
|
|
}
|
|
case _COMMENT:
|
|
tok := in.lex()
|
|
comments = append(comments, Comment{Start: tok.pos, Token: tok.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 ')':
|
|
rparen := in.lex()
|
|
x.RParen.Before = comments
|
|
x.RParen.Pos = rparen.pos
|
|
if !in.peek().isEOL() {
|
|
in.Error("syntax error (expected newline after closing paren)")
|
|
}
|
|
in.lex()
|
|
return x
|
|
default:
|
|
l := in.parseLine()
|
|
x.Line = append(x.Line, l)
|
|
l.Comment().Before = comments
|
|
comments = nil
|
|
}
|
|
}
|
|
}
|
|
|
|
func (in *input) parseLine() *Line {
|
|
tok := in.lex()
|
|
if tok.kind.isEOL() {
|
|
in.Error("internal parse error: parseLine at end of line")
|
|
}
|
|
start := tok.pos
|
|
end := tok.endPos
|
|
tokens := []string{tok.text}
|
|
for {
|
|
tok := in.lex()
|
|
if tok.kind.isEOL() {
|
|
return &Line{
|
|
Start: start,
|
|
Token: tokens,
|
|
End: end,
|
|
InBlock: true,
|
|
}
|
|
}
|
|
tokens = append(tokens, tok.text)
|
|
end = tok.endPos
|
|
}
|
|
}
|
|
|
|
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
|
|
}
|