// Copyright 2020 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 testing support.
package syntax
import (
"io"
"regexp"
)
// CommentsDo parses the given source and calls the provided handler for each
// comment or error. If the text provided to handler starts with a '/' it is
// the comment text; otherwise it is the error message.
func CommentsDo(src io.Reader, handler func(line, col uint, text string)) {
var s scanner
s.init(src, handler, comments)
for s.tok != _EOF {
s.next()
}
}
// CommentMap collects all comments in the given src with comment text
// that matches the supplied regular expression rx and returns them as
// []Error lists in a map indexed by line number. The comment text is
// the comment with any comment markers ("//", "/*", or "*/") stripped.
// The position for each Error is the position of the token immediately
// preceding the comment and the Error message is the comment text,
// with all comments that are on the same line collected in a slice, in
// source order. If there is no preceding token (the matching comment
// appears at the beginning of the file), then the recorded position
// is unknown (line, col = 0, 0). If there are no matching comments,
// the result is nil.
func CommentMap(src io.Reader, rx *regexp.Regexp) (res map[uint][]Error) {
// position of previous token
var base *PosBase
var prev struct{ line, col uint }
var s scanner
s.init(src, func(_, _ uint, text string) {
if text[0] != '/' {
return // not a comment, ignore
}
if text[1] == '*' {
text = text[:len(text)-2] // strip trailing */
}
text = text[2:] // strip leading // or /*
if rx.MatchString(text) {
pos := MakePos(base, prev.line, prev.col)
err := Error{pos, text}
if res == nil {
res = make(map[uint][]Error)
}
res[prev.line] = append(res[prev.line], err)
}
}, comments)
for s.tok != _EOF {
s.next()
if s.tok == _Semi && s.lit != "semicolon" {
continue // ignore automatically inserted semicolons
}
prev.line, prev.col = s.line, s.col
}
return
}
