diff -r 910f00ab2799 -r 0998f404dd31 vendor/github.com/russross/blackfriday/html.go --- a/vendor/github.com/russross/blackfriday/html.go Sun Jan 13 12:58:50 2019 +0100 +++ /dev/null Thu Jan 01 00:00:00 1970 +0000 @@ -1,940 +0,0 @@ -// -// Blackfriday Markdown Processor -// Available at http://github.com/russross/blackfriday -// -// Copyright © 2011 Russ Ross . -// Distributed under the Simplified BSD License. -// See README.md for details. -// - -// -// -// HTML rendering backend -// -// - -package blackfriday - -import ( - "bytes" - "fmt" - "io" - "regexp" - "strings" -) - -// HTMLFlags control optional behavior of HTML renderer. -type HTMLFlags int - -// HTML renderer configuration options. -const ( - HTMLFlagsNone HTMLFlags = 0 - SkipHTML HTMLFlags = 1 << iota // Skip preformatted HTML blocks - SkipImages // Skip embedded images - SkipLinks // Skip all links - Safelink // Only link to trusted protocols - NofollowLinks // Only link with rel="nofollow" - NoreferrerLinks // Only link with rel="noreferrer" - HrefTargetBlank // Add a blank target - CompletePage // Generate a complete HTML page - UseXHTML // Generate XHTML output instead of HTML - FootnoteReturnLinks // Generate a link at the end of a footnote to return to the source - Smartypants // Enable smart punctuation substitutions - SmartypantsFractions // Enable smart fractions (with Smartypants) - SmartypantsDashes // Enable smart dashes (with Smartypants) - SmartypantsLatexDashes // Enable LaTeX-style dashes (with Smartypants) - SmartypantsAngledQuotes // Enable angled double quotes (with Smartypants) for double quotes rendering - SmartypantsQuotesNBSP // Enable « French guillemets » (with Smartypants) - TOC // Generate a table of contents -) - -var ( - htmlTagRe = regexp.MustCompile("(?i)^" + htmlTag) -) - -const ( - htmlTag = "(?:" + openTag + "|" + closeTag + "|" + htmlComment + "|" + - processingInstruction + "|" + declaration + "|" + cdata + ")" - closeTag = "]" - openTag = "<" + tagName + attribute + "*" + "\\s*/?>" - attribute = "(?:" + "\\s+" + attributeName + attributeValueSpec + "?)" - attributeValue = "(?:" + unquotedValue + "|" + singleQuotedValue + "|" + doubleQuotedValue + ")" - attributeValueSpec = "(?:" + "\\s*=" + "\\s*" + attributeValue + ")" - attributeName = "[a-zA-Z_:][a-zA-Z0-9:._-]*" - cdata = "" - declaration = "]*>" - doubleQuotedValue = "\"[^\"]*\"" - htmlComment = "|" - processingInstruction = "[<][?].*?[?][>]" - singleQuotedValue = "'[^']*'" - tagName = "[A-Za-z][A-Za-z0-9-]*" - unquotedValue = "[^\"'=<>`\\x00-\\x20]+" -) - -// HTMLRendererParameters is a collection of supplementary parameters tweaking -// the behavior of various parts of HTML renderer. -type HTMLRendererParameters struct { - // Prepend this text to each relative URL. - AbsolutePrefix string - // Add this text to each footnote anchor, to ensure uniqueness. - FootnoteAnchorPrefix string - // Show this text inside the tag for a footnote return link, if the - // HTML_FOOTNOTE_RETURN_LINKS flag is enabled. If blank, the string - // [return] is used. - FootnoteReturnLinkContents string - // If set, add this text to the front of each Heading ID, to ensure - // uniqueness. - HeadingIDPrefix string - // If set, add this text to the back of each Heading ID, to ensure uniqueness. - HeadingIDSuffix string - - Title string // Document title (used if CompletePage is set) - CSS string // Optional CSS file URL (used if CompletePage is set) - Icon string // Optional icon file URL (used if CompletePage is set) - - Flags HTMLFlags // Flags allow customizing this renderer's behavior -} - -// HTMLRenderer is a type that implements the Renderer interface for HTML output. -// -// Do not create this directly, instead use the NewHTMLRenderer function. -type HTMLRenderer struct { - HTMLRendererParameters - - closeTag string // how to end singleton tags: either " />" or ">" - - // Track heading IDs to prevent ID collision in a single generation. - headingIDs map[string]int - - lastOutputLen int - disableTags int - - sr *SPRenderer -} - -const ( - xhtmlClose = " />" - htmlClose = ">" -) - -// NewHTMLRenderer creates and configures an HTMLRenderer object, which -// satisfies the Renderer interface. -func NewHTMLRenderer(params HTMLRendererParameters) *HTMLRenderer { - // configure the rendering engine - closeTag := htmlClose - if params.Flags&UseXHTML != 0 { - closeTag = xhtmlClose - } - - if params.FootnoteReturnLinkContents == "" { - params.FootnoteReturnLinkContents = `[return]` - } - - return &HTMLRenderer{ - HTMLRendererParameters: params, - - closeTag: closeTag, - headingIDs: make(map[string]int), - - sr: NewSmartypantsRenderer(params.Flags), - } -} - -func isHTMLTag(tag []byte, tagname string) bool { - found, _ := findHTMLTagPos(tag, tagname) - return found -} - -// Look for a character, but ignore it when it's in any kind of quotes, it -// might be JavaScript -func skipUntilCharIgnoreQuotes(html []byte, start int, char byte) int { - inSingleQuote := false - inDoubleQuote := false - inGraveQuote := false - i := start - for i < len(html) { - switch { - case html[i] == char && !inSingleQuote && !inDoubleQuote && !inGraveQuote: - return i - case html[i] == '\'': - inSingleQuote = !inSingleQuote - case html[i] == '"': - inDoubleQuote = !inDoubleQuote - case html[i] == '`': - inGraveQuote = !inGraveQuote - } - i++ - } - return start -} - -func findHTMLTagPos(tag []byte, tagname string) (bool, int) { - i := 0 - if i < len(tag) && tag[0] != '<' { - return false, -1 - } - i++ - i = skipSpace(tag, i) - - if i < len(tag) && tag[i] == '/' { - i++ - } - - i = skipSpace(tag, i) - j := 0 - for ; i < len(tag); i, j = i+1, j+1 { - if j >= len(tagname) { - break - } - - if strings.ToLower(string(tag[i]))[0] != tagname[j] { - return false, -1 - } - } - - if i == len(tag) { - return false, -1 - } - - rightAngle := skipUntilCharIgnoreQuotes(tag, i, '>') - if rightAngle >= i { - return true, rightAngle - } - - return false, -1 -} - -func skipSpace(tag []byte, i int) int { - for i < len(tag) && isspace(tag[i]) { - i++ - } - return i -} - -func isRelativeLink(link []byte) (yes bool) { - // a tag begin with '#' - if link[0] == '#' { - return true - } - - // link begin with '/' but not '//', the second maybe a protocol relative link - if len(link) >= 2 && link[0] == '/' && link[1] != '/' { - return true - } - - // only the root '/' - if len(link) == 1 && link[0] == '/' { - return true - } - - // current directory : begin with "./" - if bytes.HasPrefix(link, []byte("./")) { - return true - } - - // parent directory : begin with "../" - if bytes.HasPrefix(link, []byte("../")) { - return true - } - - return false -} - -func (r *HTMLRenderer) ensureUniqueHeadingID(id string) string { - for count, found := r.headingIDs[id]; found; count, found = r.headingIDs[id] { - tmp := fmt.Sprintf("%s-%d", id, count+1) - - if _, tmpFound := r.headingIDs[tmp]; !tmpFound { - r.headingIDs[id] = count + 1 - id = tmp - } else { - id = id + "-1" - } - } - - if _, found := r.headingIDs[id]; !found { - r.headingIDs[id] = 0 - } - - return id -} - -func (r *HTMLRenderer) addAbsPrefix(link []byte) []byte { - if r.AbsolutePrefix != "" && isRelativeLink(link) && link[0] != '.' { - newDest := r.AbsolutePrefix - if link[0] != '/' { - newDest += "/" - } - newDest += string(link) - return []byte(newDest) - } - return link -} - -func appendLinkAttrs(attrs []string, flags HTMLFlags, link []byte) []string { - if isRelativeLink(link) { - return attrs - } - val := []string{} - if flags&NofollowLinks != 0 { - val = append(val, "nofollow") - } - if flags&NoreferrerLinks != 0 { - val = append(val, "noreferrer") - } - if flags&HrefTargetBlank != 0 { - attrs = append(attrs, "target=\"_blank\"") - } - if len(val) == 0 { - return attrs - } - attr := fmt.Sprintf("rel=%q", strings.Join(val, " ")) - return append(attrs, attr) -} - -func isMailto(link []byte) bool { - return bytes.HasPrefix(link, []byte("mailto:")) -} - -func needSkipLink(flags HTMLFlags, dest []byte) bool { - if flags&SkipLinks != 0 { - return true - } - return flags&Safelink != 0 && !isSafeLink(dest) && !isMailto(dest) -} - -func isSmartypantable(node *Node) bool { - pt := node.Parent.Type - return pt != Link && pt != CodeBlock && pt != Code -} - -func appendLanguageAttr(attrs []string, info []byte) []string { - if len(info) == 0 { - return attrs - } - endOfLang := bytes.IndexAny(info, "\t ") - if endOfLang < 0 { - endOfLang = len(info) - } - return append(attrs, fmt.Sprintf("class=\"language-%s\"", info[:endOfLang])) -} - -func (r *HTMLRenderer) tag(w io.Writer, name []byte, attrs []string) { - w.Write(name) - if len(attrs) > 0 { - w.Write(spaceBytes) - w.Write([]byte(strings.Join(attrs, " "))) - } - w.Write(gtBytes) - r.lastOutputLen = 1 -} - -func footnoteRef(prefix string, node *Node) []byte { - urlFrag := prefix + string(slugify(node.Destination)) - anchor := fmt.Sprintf(`%d`, urlFrag, node.NoteID) - return []byte(fmt.Sprintf(`%s`, urlFrag, anchor)) -} - -func footnoteItem(prefix string, slug []byte) []byte { - return []byte(fmt.Sprintf(`
  • `, prefix, slug)) -} - -func footnoteReturnLink(prefix, returnLink string, slug []byte) []byte { - const format = ` %s` - return []byte(fmt.Sprintf(format, prefix, slug, returnLink)) -} - -func itemOpenCR(node *Node) bool { - if node.Prev == nil { - return false - } - ld := node.Parent.ListData - return !ld.Tight && ld.ListFlags&ListTypeDefinition == 0 -} - -func skipParagraphTags(node *Node) bool { - grandparent := node.Parent.Parent - if grandparent == nil || grandparent.Type != List { - return false - } - tightOrTerm := grandparent.Tight || node.Parent.ListFlags&ListTypeTerm != 0 - return grandparent.Type == List && tightOrTerm -} - -func cellAlignment(align CellAlignFlags) string { - switch align { - case TableAlignmentLeft: - return "left" - case TableAlignmentRight: - return "right" - case TableAlignmentCenter: - return "center" - default: - return "" - } -} - -func (r *HTMLRenderer) out(w io.Writer, text []byte) { - if r.disableTags > 0 { - w.Write(htmlTagRe.ReplaceAll(text, []byte{})) - } else { - w.Write(text) - } - r.lastOutputLen = len(text) -} - -func (r *HTMLRenderer) cr(w io.Writer) { - if r.lastOutputLen > 0 { - r.out(w, nlBytes) - } -} - -var ( - nlBytes = []byte{'\n'} - gtBytes = []byte{'>'} - spaceBytes = []byte{' '} -) - -var ( - brTag = []byte("
    ") - brXHTMLTag = []byte("
    ") - emTag = []byte("") - emCloseTag = []byte("") - strongTag = []byte("") - strongCloseTag = []byte("") - delTag = []byte("") - delCloseTag = []byte("") - ttTag = []byte("") - ttCloseTag = []byte("") - aTag = []byte("") - preTag = []byte("
    ")
-	preCloseTag        = []byte("
    ") - codeTag = []byte("") - codeCloseTag = []byte("") - pTag = []byte("

    ") - pCloseTag = []byte("

    ") - blockquoteTag = []byte("
    ") - blockquoteCloseTag = []byte("
    ") - hrTag = []byte("
    ") - hrXHTMLTag = []byte("
    ") - ulTag = []byte("
      ") - ulCloseTag = []byte("
    ") - olTag = []byte("
      ") - olCloseTag = []byte("
    ") - dlTag = []byte("
    ") - dlCloseTag = []byte("
    ") - liTag = []byte("
  • ") - liCloseTag = []byte("
    • ") - ddTag = []byte("
    ") - ddCloseTag = []byte("
    ") - dtTag = []byte("
    ") - dtCloseTag = []byte("
    ") - tableTag = []byte("") - tableCloseTag = []byte("
    ") - tdTag = []byte("") - thTag = []byte("") - theadTag = []byte("") - theadCloseTag = []byte("") - tbodyTag = []byte("") - tbodyCloseTag = []byte("") - trTag = []byte("") - trCloseTag = []byte("") - h1Tag = []byte("") - h2Tag = []byte("") - h3Tag = []byte("") - h4Tag = []byte("") - h5Tag = []byte("") - h6Tag = []byte("") - - footnotesDivBytes = []byte("\n
    \n\n") - footnotesCloseDivBytes = []byte("\n
    \n") -) - -func headingTagsFromLevel(level int) ([]byte, []byte) { - switch level { - case 1: - return h1Tag, h1CloseTag - case 2: - return h2Tag, h2CloseTag - case 3: - return h3Tag, h3CloseTag - case 4: - return h4Tag, h4CloseTag - case 5: - return h5Tag, h5CloseTag - default: - return h6Tag, h6CloseTag - } -} - -func (r *HTMLRenderer) outHRTag(w io.Writer) { - if r.Flags&UseXHTML == 0 { - r.out(w, hrTag) - } else { - r.out(w, hrXHTMLTag) - } -} - -// RenderNode is a default renderer of a single node of a syntax tree. For -// block nodes it will be called twice: first time with entering=true, second -// time with entering=false, so that it could know when it's working on an open -// tag and when on close. It writes the result to w. -// -// The return value is a way to tell the calling walker to adjust its walk -// pattern: e.g. it can terminate the traversal by returning Terminate. Or it -// can ask the walker to skip a subtree of this node by returning SkipChildren. -// The typical behavior is to return GoToNext, which asks for the usual -// traversal to the next node. -func (r *HTMLRenderer) RenderNode(w io.Writer, node *Node, entering bool) WalkStatus { - attrs := []string{} - switch node.Type { - case Text: - if r.Flags&Smartypants != 0 { - var tmp bytes.Buffer - escapeHTML(&tmp, node.Literal) - r.sr.Process(w, tmp.Bytes()) - } else { - if node.Parent.Type == Link { - escLink(w, node.Literal) - } else { - escapeHTML(w, node.Literal) - } - } - case Softbreak: - r.cr(w) - // TODO: make it configurable via out(renderer.softbreak) - case Hardbreak: - if r.Flags&UseXHTML == 0 { - r.out(w, brTag) - } else { - r.out(w, brXHTMLTag) - } - r.cr(w) - case Emph: - if entering { - r.out(w, emTag) - } else { - r.out(w, emCloseTag) - } - case Strong: - if entering { - r.out(w, strongTag) - } else { - r.out(w, strongCloseTag) - } - case Del: - if entering { - r.out(w, delTag) - } else { - r.out(w, delCloseTag) - } - case HTMLSpan: - if r.Flags&SkipHTML != 0 { - break - } - r.out(w, node.Literal) - case Link: - // mark it but don't link it if it is not a safe link: no smartypants - dest := node.LinkData.Destination - if needSkipLink(r.Flags, dest) { - if entering { - r.out(w, ttTag) - } else { - r.out(w, ttCloseTag) - } - } else { - if entering { - dest = r.addAbsPrefix(dest) - var hrefBuf bytes.Buffer - hrefBuf.WriteString("href=\"") - escLink(&hrefBuf, dest) - hrefBuf.WriteByte('"') - attrs = append(attrs, hrefBuf.String()) - if node.NoteID != 0 { - r.out(w, footnoteRef(r.FootnoteAnchorPrefix, node)) - break - } - attrs = appendLinkAttrs(attrs, r.Flags, dest) - if len(node.LinkData.Title) > 0 { - var titleBuff bytes.Buffer - titleBuff.WriteString("title=\"") - escapeHTML(&titleBuff, node.LinkData.Title) - titleBuff.WriteByte('"') - attrs = append(attrs, titleBuff.String()) - } - r.tag(w, aTag, attrs) - } else { - if node.NoteID != 0 { - break - } - r.out(w, aCloseTag) - } - } - case Image: - if r.Flags&SkipImages != 0 { - return SkipChildren - } - if entering { - dest := node.LinkData.Destination - dest = r.addAbsPrefix(dest) - if r.disableTags == 0 { - //if options.safe && potentiallyUnsafe(dest) { - //out(w, ``) - //} else { - r.out(w, []byte(`<img src=`)) - } - } - case Code: - r.out(w, codeTag) - escapeHTML(w, node.Literal) - r.out(w, codeCloseTag) - case Document: - break - case Paragraph: - if skipParagraphTags(node) { - break - } - if entering { - // TODO: untangle this clusterfuck about when the newlines need - // to be added and when not. - if node.Prev != nil { - switch node.Prev.Type { - case HTMLBlock, List, Paragraph, Heading, CodeBlock, BlockQuote, HorizontalRule: - r.cr(w) - } - } - if node.Parent.Type == BlockQuote && node.Prev == nil { - r.cr(w) - } - r.out(w, pTag) - } else { - r.out(w, pCloseTag) - if !(node.Parent.Type == Item && node.Next == nil) { - r.cr(w) - } - } - case BlockQuote: - if entering { - r.cr(w) - r.out(w, blockquoteTag) - } else { - r.out(w, blockquoteCloseTag) - r.cr(w) - } - case HTMLBlock: - if r.Flags&SkipHTML != 0 { - break - } - r.cr(w) - r.out(w, node.Literal) - r.cr(w) - case Heading: - openTag, closeTag := headingTagsFromLevel(node.Level) - if entering { - if node.IsTitleblock { - attrs = append(attrs, `class="title"`) - } - if node.HeadingID != "" { - id := r.ensureUniqueHeadingID(node.HeadingID) - if r.HeadingIDPrefix != "" { - id = r.HeadingIDPrefix + id - } - if r.HeadingIDSuffix != "" { - id = id + r.HeadingIDSuffix - } - attrs = append(attrs, fmt.Sprintf(`id="%s"`, id)) - } - r.cr(w) - r.tag(w, openTag, attrs) - } else { - r.out(w, closeTag) - if !(node.Parent.Type == Item && node.Next == nil) { - r.cr(w) - } - } - case HorizontalRule: - r.cr(w) - r.outHRTag(w) - r.cr(w) - case List: - openTag := ulTag - closeTag := ulCloseTag - if node.ListFlags&ListTypeOrdered != 0 { - openTag = olTag - closeTag = olCloseTag - } - if node.ListFlags&ListTypeDefinition != 0 { - openTag = dlTag - closeTag = dlCloseTag - } - if entering { - if node.IsFootnotesList { - r.out(w, footnotesDivBytes) - r.outHRTag(w) - r.cr(w) - } - r.cr(w) - if node.Parent.Type == Item && node.Parent.Parent.Tight { - r.cr(w) - } - r.tag(w, openTag[:len(openTag)-1], attrs) - r.cr(w) - } else { - r.out(w, closeTag) - //cr(w) - //if node.parent.Type != Item { - // cr(w) - //} - if node.Parent.Type == Item && node.Next != nil { - r.cr(w) - } - if node.Parent.Type == Document || node.Parent.Type == BlockQuote { - r.cr(w) - } - if node.IsFootnotesList { - r.out(w, footnotesCloseDivBytes) - } - } - case Item: - openTag := liTag - closeTag := liCloseTag - if node.ListFlags&ListTypeDefinition != 0 { - openTag = ddTag - closeTag = ddCloseTag - } - if node.ListFlags&ListTypeTerm != 0 { - openTag = dtTag - closeTag = dtCloseTag - } - if entering { - if itemOpenCR(node) { - r.cr(w) - } - if node.ListData.RefLink != nil { - slug := slugify(node.ListData.RefLink) - r.out(w, footnoteItem(r.FootnoteAnchorPrefix, slug)) - break - } - r.out(w, openTag) - } else { - if node.ListData.RefLink != nil { - slug := slugify(node.ListData.RefLink) - if r.Flags&FootnoteReturnLinks != 0 { - r.out(w, footnoteReturnLink(r.FootnoteAnchorPrefix, r.FootnoteReturnLinkContents, slug)) - } - } - r.out(w, closeTag) - r.cr(w) - } - case CodeBlock: - attrs = appendLanguageAttr(attrs, node.Info) - r.cr(w) - r.out(w, preTag) - r.tag(w, codeTag[:len(codeTag)-1], attrs) - escapeHTML(w, node.Literal) - r.out(w, codeCloseTag) - r.out(w, preCloseTag) - if node.Parent.Type != Item { - r.cr(w) - } - case Table: - if entering { - r.cr(w) - r.out(w, tableTag) - } else { - r.out(w, tableCloseTag) - r.cr(w) - } - case TableCell: - openTag := tdTag - closeTag := tdCloseTag - if node.IsHeader { - openTag = thTag - closeTag = thCloseTag - } - if entering { - align := cellAlignment(node.Align) - if align != "" { - attrs = append(attrs, fmt.Sprintf(`align="%s"`, align)) - } - if node.Prev == nil { - r.cr(w) - } - r.tag(w, openTag, attrs) - } else { - r.out(w, closeTag) - r.cr(w) - } - case TableHead: - if entering { - r.cr(w) - r.out(w, theadTag) - } else { - r.out(w, theadCloseTag) - r.cr(w) - } - case TableBody: - if entering { - r.cr(w) - r.out(w, tbodyTag) - // XXX: this is to adhere to a rather silly test. Should fix test. - if node.FirstChild == nil { - r.cr(w) - } - } else { - r.out(w, tbodyCloseTag) - r.cr(w) - } - case TableRow: - if entering { - r.cr(w) - r.out(w, trTag) - } else { - r.out(w, trCloseTag) - r.cr(w) - } - default: - panic("Unknown node type " + node.Type.String()) - } - return GoToNext -} - -// RenderHeader writes HTML document preamble and TOC if requested. -func (r *HTMLRenderer) RenderHeader(w io.Writer, ast *Node) { - r.writeDocumentHeader(w) - if r.Flags&TOC != 0 { - r.writeTOC(w, ast) - } -} - -// RenderFooter writes HTML document footer. -func (r *HTMLRenderer) RenderFooter(w io.Writer, ast *Node) { - if r.Flags&CompletePage == 0 { - return - } - io.WriteString(w, "\n\n\n") -} - -func (r *HTMLRenderer) writeDocumentHeader(w io.Writer) { - if r.Flags&CompletePage == 0 { - return - } - ending := "" - if r.Flags&UseXHTML != 0 { - io.WriteString(w, "\n") - io.WriteString(w, "\n") - ending = " /" - } else { - io.WriteString(w, "\n") - io.WriteString(w, "\n") - } - io.WriteString(w, "\n") - io.WriteString(w, " ") - if r.Flags&Smartypants != 0 { - r.sr.Process(w, []byte(r.Title)) - } else { - escapeHTML(w, []byte(r.Title)) - } - io.WriteString(w, "\n") - io.WriteString(w, " \n") - io.WriteString(w, " \n") - if r.CSS != "" { - io.WriteString(w, " \n") - } - if r.Icon != "" { - io.WriteString(w, " \n") - } - io.WriteString(w, "\n") - io.WriteString(w, "\n\n") -} - -func (r *HTMLRenderer) writeTOC(w io.Writer, ast *Node) { - buf := bytes.Buffer{} - - inHeading := false - tocLevel := 0 - headingCount := 0 - - ast.Walk(func(node *Node, entering bool) WalkStatus { - if node.Type == Heading && !node.HeadingData.IsTitleblock { - inHeading = entering - if entering { - node.HeadingID = fmt.Sprintf("toc_%d", headingCount) - if node.Level == tocLevel { - buf.WriteString("\n\n
  • ") - } else if node.Level < tocLevel { - for node.Level < tocLevel { - tocLevel-- - buf.WriteString("
    • \n") - } - buf.WriteString("\n\n
  • ") - } else { - for node.Level > tocLevel { - tocLevel++ - buf.WriteString("\n") - } - - if buf.Len() > 0 { - io.WriteString(w, "\n") - } - r.lastOutputLen = buf.Len() -}