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author | Tianon Gravi <admwiggin@gmail.com> | 2015-01-15 11:54:00 -0700 |
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committer | Tianon Gravi <admwiggin@gmail.com> | 2015-01-15 11:54:00 -0700 |
commit | f154da9e12608589e8d5f0508f908a0c3e88a1bb (patch) | |
tree | f8255d51e10c6f1e0ed69702200b966c9556a431 /src/pkg/go/doc/comment.go | |
parent | 8d8329ed5dfb9622c82a9fbec6fd99a580f9c9f6 (diff) | |
download | golang-upstream/1.4.tar.gz |
Imported Upstream version 1.4upstream/1.4
Diffstat (limited to 'src/pkg/go/doc/comment.go')
-rw-r--r-- | src/pkg/go/doc/comment.go | 480 |
1 files changed, 0 insertions, 480 deletions
diff --git a/src/pkg/go/doc/comment.go b/src/pkg/go/doc/comment.go deleted file mode 100644 index f414ca409..000000000 --- a/src/pkg/go/doc/comment.go +++ /dev/null @@ -1,480 +0,0 @@ -// Copyright 2009 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. - -// Godoc comment extraction and comment -> HTML formatting. - -package doc - -import ( - "io" - "regexp" - "strings" - "text/template" // for HTMLEscape - "unicode" - "unicode/utf8" -) - -var ( - ldquo = []byte("“") - rdquo = []byte("”") -) - -// Escape comment text for HTML. If nice is set, -// also turn `` into “ and '' into ”. -func commentEscape(w io.Writer, text string, nice bool) { - last := 0 - if nice { - for i := 0; i < len(text)-1; i++ { - ch := text[i] - if ch == text[i+1] && (ch == '`' || ch == '\'') { - template.HTMLEscape(w, []byte(text[last:i])) - last = i + 2 - switch ch { - case '`': - w.Write(ldquo) - case '\'': - w.Write(rdquo) - } - i++ // loop will add one more - } - } - } - template.HTMLEscape(w, []byte(text[last:])) -} - -const ( - // Regexp for Go identifiers - identRx = `[\pL_][\pL_0-9]*` - - // Regexp for URLs - protocol = `https?|ftp|file|gopher|mailto|news|nntp|telnet|wais|prospero` - hostPart = `[a-zA-Z0-9_@\-]+` - filePart = `[a-zA-Z0-9_?%#~&/\-+=()]+` // parentheses may not be matching; see pairedParensPrefixLen - urlRx = `(` + protocol + `)://` + // http:// - hostPart + `([.:]` + hostPart + `)*/?` + // //www.google.com:8080/ - filePart + `([:.,]` + filePart + `)*` -) - -var matchRx = regexp.MustCompile(`(` + urlRx + `)|(` + identRx + `)`) - -var ( - html_a = []byte(`<a href="`) - html_aq = []byte(`">`) - html_enda = []byte("</a>") - html_i = []byte("<i>") - html_endi = []byte("</i>") - html_p = []byte("<p>\n") - html_endp = []byte("</p>\n") - html_pre = []byte("<pre>") - html_endpre = []byte("</pre>\n") - html_h = []byte(`<h3 id="`) - html_hq = []byte(`">`) - html_endh = []byte("</h3>\n") -) - -// pairedParensPrefixLen returns the length of the longest prefix of s containing paired parentheses. -func pairedParensPrefixLen(s string) int { - parens := 0 - l := len(s) - for i, ch := range s { - switch ch { - case '(': - if parens == 0 { - l = i - } - parens++ - case ')': - parens-- - if parens == 0 { - l = len(s) - } else if parens < 0 { - return i - } - } - } - return l -} - -// Emphasize and escape a line of text for HTML. URLs are converted into links; -// if the URL also appears in the words map, the link is taken from the map (if -// the corresponding map value is the empty string, the URL is not converted -// into a link). Go identifiers that appear in the words map are italicized; if -// the corresponding map value is not the empty string, it is considered a URL -// and the word is converted into a link. If nice is set, the remaining text's -// appearance is improved where it makes sense (e.g., `` is turned into “ -// and '' into ”). -func emphasize(w io.Writer, line string, words map[string]string, nice bool) { - for { - m := matchRx.FindStringSubmatchIndex(line) - if m == nil { - break - } - // m >= 6 (two parenthesized sub-regexps in matchRx, 1st one is urlRx) - - // write text before match - commentEscape(w, line[0:m[0]], nice) - - // adjust match if necessary - match := line[m[0]:m[1]] - if n := pairedParensPrefixLen(match); n < len(match) { - // match contains unpaired parentheses (rare); - // redo matching with shortened line for correct indices - m = matchRx.FindStringSubmatchIndex(line[:m[0]+n]) - match = match[:n] - } - - // analyze match - url := "" - italics := false - if words != nil { - url, italics = words[match] - } - if m[2] >= 0 { - // match against first parenthesized sub-regexp; must be match against urlRx - if !italics { - // no alternative URL in words list, use match instead - url = match - } - italics = false // don't italicize URLs - } - - // write match - if len(url) > 0 { - w.Write(html_a) - template.HTMLEscape(w, []byte(url)) - w.Write(html_aq) - } - if italics { - w.Write(html_i) - } - commentEscape(w, match, nice) - if italics { - w.Write(html_endi) - } - if len(url) > 0 { - w.Write(html_enda) - } - - // advance - line = line[m[1]:] - } - commentEscape(w, line, nice) -} - -func indentLen(s string) int { - i := 0 - for i < len(s) && (s[i] == ' ' || s[i] == '\t') { - i++ - } - return i -} - -func isBlank(s string) bool { - return len(s) == 0 || (len(s) == 1 && s[0] == '\n') -} - -func commonPrefix(a, b string) string { - i := 0 - for i < len(a) && i < len(b) && a[i] == b[i] { - i++ - } - return a[0:i] -} - -func unindent(block []string) { - if len(block) == 0 { - return - } - - // compute maximum common white prefix - prefix := block[0][0:indentLen(block[0])] - for _, line := range block { - if !isBlank(line) { - prefix = commonPrefix(prefix, line[0:indentLen(line)]) - } - } - n := len(prefix) - - // remove - for i, line := range block { - if !isBlank(line) { - block[i] = line[n:] - } - } -} - -// heading returns the trimmed line if it passes as a section heading; -// otherwise it returns the empty string. -func heading(line string) string { - line = strings.TrimSpace(line) - if len(line) == 0 { - return "" - } - - // a heading must start with an uppercase letter - r, _ := utf8.DecodeRuneInString(line) - if !unicode.IsLetter(r) || !unicode.IsUpper(r) { - return "" - } - - // it must end in a letter or digit: - r, _ = utf8.DecodeLastRuneInString(line) - if !unicode.IsLetter(r) && !unicode.IsDigit(r) { - return "" - } - - // exclude lines with illegal characters - if strings.IndexAny(line, ",.;:!?+*/=()[]{}_^°&§~%#@<\">\\") >= 0 { - return "" - } - - // allow "'" for possessive "'s" only - for b := line; ; { - i := strings.IndexRune(b, '\'') - if i < 0 { - break - } - if i+1 >= len(b) || b[i+1] != 's' || (i+2 < len(b) && b[i+2] != ' ') { - return "" // not followed by "s " - } - b = b[i+2:] - } - - return line -} - -type op int - -const ( - opPara op = iota - opHead - opPre -) - -type block struct { - op op - lines []string -} - -var nonAlphaNumRx = regexp.MustCompile(`[^a-zA-Z0-9]`) - -func anchorID(line string) string { - // Add a "hdr-" prefix to avoid conflicting with IDs used for package symbols. - return "hdr-" + nonAlphaNumRx.ReplaceAllString(line, "_") -} - -// ToHTML converts comment text to formatted HTML. -// The comment was prepared by DocReader, -// so it is known not to have leading, trailing blank lines -// nor to have trailing spaces at the end of lines. -// The comment markers have already been removed. -// -// Each span of unindented non-blank lines is converted into -// a single paragraph. There is one exception to the rule: a span that -// consists of a single line, is followed by another paragraph span, -// begins with a capital letter, and contains no punctuation -// is formatted as a heading. -// -// A span of indented lines is converted into a <pre> block, -// with the common indent prefix removed. -// -// URLs in the comment text are converted into links; if the URL also appears -// in the words map, the link is taken from the map (if the corresponding map -// value is the empty string, the URL is not converted into a link). -// -// Go identifiers that appear in the words map are italicized; if the corresponding -// map value is not the empty string, it is considered a URL and the word is converted -// into a link. -func ToHTML(w io.Writer, text string, words map[string]string) { - for _, b := range blocks(text) { - switch b.op { - case opPara: - w.Write(html_p) - for _, line := range b.lines { - emphasize(w, line, words, true) - } - w.Write(html_endp) - case opHead: - w.Write(html_h) - id := "" - for _, line := range b.lines { - if id == "" { - id = anchorID(line) - w.Write([]byte(id)) - w.Write(html_hq) - } - commentEscape(w, line, true) - } - if id == "" { - w.Write(html_hq) - } - w.Write(html_endh) - case opPre: - w.Write(html_pre) - for _, line := range b.lines { - emphasize(w, line, nil, false) - } - w.Write(html_endpre) - } - } -} - -func blocks(text string) []block { - var ( - out []block - para []string - - lastWasBlank = false - lastWasHeading = false - ) - - close := func() { - if para != nil { - out = append(out, block{opPara, para}) - para = nil - } - } - - lines := strings.SplitAfter(text, "\n") - unindent(lines) - for i := 0; i < len(lines); { - line := lines[i] - if isBlank(line) { - // close paragraph - close() - i++ - lastWasBlank = true - continue - } - if indentLen(line) > 0 { - // close paragraph - close() - - // count indented or blank lines - j := i + 1 - for j < len(lines) && (isBlank(lines[j]) || indentLen(lines[j]) > 0) { - j++ - } - // but not trailing blank lines - for j > i && isBlank(lines[j-1]) { - j-- - } - pre := lines[i:j] - i = j - - unindent(pre) - - // put those lines in a pre block - out = append(out, block{opPre, pre}) - lastWasHeading = false - continue - } - - if lastWasBlank && !lastWasHeading && i+2 < len(lines) && - isBlank(lines[i+1]) && !isBlank(lines[i+2]) && indentLen(lines[i+2]) == 0 { - // current line is non-blank, surrounded by blank lines - // and the next non-blank line is not indented: this - // might be a heading. - if head := heading(line); head != "" { - close() - out = append(out, block{opHead, []string{head}}) - i += 2 - lastWasHeading = true - continue - } - } - - // open paragraph - lastWasBlank = false - lastWasHeading = false - para = append(para, lines[i]) - i++ - } - close() - - return out -} - -// ToText prepares comment text for presentation in textual output. -// It wraps paragraphs of text to width or fewer Unicode code points -// and then prefixes each line with the indent. In preformatted sections -// (such as program text), it prefixes each non-blank line with preIndent. -func ToText(w io.Writer, text string, indent, preIndent string, width int) { - l := lineWrapper{ - out: w, - width: width, - indent: indent, - } - for _, b := range blocks(text) { - switch b.op { - case opPara: - // l.write will add leading newline if required - for _, line := range b.lines { - l.write(line) - } - l.flush() - case opHead: - w.Write(nl) - for _, line := range b.lines { - l.write(line + "\n") - } - l.flush() - case opPre: - w.Write(nl) - for _, line := range b.lines { - if isBlank(line) { - w.Write([]byte("\n")) - } else { - w.Write([]byte(preIndent)) - w.Write([]byte(line)) - } - } - } - } -} - -type lineWrapper struct { - out io.Writer - printed bool - width int - indent string - n int - pendSpace int -} - -var nl = []byte("\n") -var space = []byte(" ") - -func (l *lineWrapper) write(text string) { - if l.n == 0 && l.printed { - l.out.Write(nl) // blank line before new paragraph - } - l.printed = true - - for _, f := range strings.Fields(text) { - w := utf8.RuneCountInString(f) - // wrap if line is too long - if l.n > 0 && l.n+l.pendSpace+w > l.width { - l.out.Write(nl) - l.n = 0 - l.pendSpace = 0 - } - if l.n == 0 { - l.out.Write([]byte(l.indent)) - } - l.out.Write(space[:l.pendSpace]) - l.out.Write([]byte(f)) - l.n += l.pendSpace + w - l.pendSpace = 1 - } -} - -func (l *lineWrapper) flush() { - if l.n == 0 { - return - } - l.out.Write(nl) - l.pendSpace = 0 - l.n = 0 -} |