--- /dev/null
+// 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.
+
+// This file contains support functions for parsing .go files
+// accessed via godoc's file system fs.
+
+package godoc
+
+import (
+ "bytes"
+ "go/ast"
+ "go/parser"
+ "go/token"
+ pathpkg "path"
+
+ "golang.org/x/tools/godoc/vfs"
+)
+
+var linePrefix = []byte("//line ")
+
+// This function replaces source lines starting with "//line " with a blank line.
+// It does this irrespective of whether the line is truly a line comment or not;
+// e.g., the line may be inside a string, or a /*-style comment; however that is
+// rather unlikely (proper testing would require a full Go scan which we want to
+// avoid for performance).
+func replaceLinePrefixCommentsWithBlankLine(src []byte) {
+ for {
+ i := bytes.Index(src, linePrefix)
+ if i < 0 {
+ break // we're done
+ }
+ // 0 <= i && i+len(linePrefix) <= len(src)
+ if i == 0 || src[i-1] == '\n' {
+ // at beginning of line: blank out line
+ for i < len(src) && src[i] != '\n' {
+ src[i] = ' '
+ i++
+ }
+ } else {
+ // not at beginning of line: skip over prefix
+ i += len(linePrefix)
+ }
+ // i <= len(src)
+ src = src[i:]
+ }
+}
+
+func (c *Corpus) parseFile(fset *token.FileSet, filename string, mode parser.Mode) (*ast.File, error) {
+ src, err := vfs.ReadFile(c.fs, filename)
+ if err != nil {
+ return nil, err
+ }
+
+ // Temporary ad-hoc fix for issue 5247.
+ // TODO(gri,dmitshur) Remove this in favor of a better fix, eventually (see issue 32092).
+ replaceLinePrefixCommentsWithBlankLine(src)
+
+ return parser.ParseFile(fset, filename, src, mode)
+}
+
+func (c *Corpus) parseFiles(fset *token.FileSet, relpath string, abspath string, localnames []string) (map[string]*ast.File, error) {
+ files := make(map[string]*ast.File)
+ for _, f := range localnames {
+ absname := pathpkg.Join(abspath, f)
+ file, err := c.parseFile(fset, absname, parser.ParseComments)
+ if err != nil {
+ return nil, err
+ }
+ files[pathpkg.Join(relpath, f)] = file
+ }
+
+ return files, nil
+}