Update markdown parsing library to github.com/gomarkdown/markdown (#944)

vendor/github.com/gomarkdown/markdown/html/callouts.go

@@ -0,0 +1,42 @@
+package html
+
+import (
+	"bytes"
+	"io"
+
+	"github.com/gomarkdown/markdown/ast"
+	"github.com/gomarkdown/markdown/parser"
+)
+
+// EscapeHTMLCallouts writes html-escaped d to w. It escapes &, <, > and " characters, *but*
+// expands callouts <<N>> with the callout HTML, i.e. by calling r.callout() with a newly created
+// ast.Callout node.
+func (r *Renderer) EscapeHTMLCallouts(w io.Writer, d []byte) {
+	ld := len(d)
+Parse:
+	for i := 0; i < ld; i++ {
+		for _, comment := range r.opts.Comments {
+			if !bytes.HasPrefix(d[i:], comment) {
+				break
+			}
+
+			lc := len(comment)
+			if i+lc < ld {
+				if id, consumed := parser.IsCallout(d[i+lc:]); consumed > 0 {
+					// We have seen a callout
+					callout := &ast.Callout{ID: id}
+					r.callout(w, callout)
+					i += consumed + lc - 1
+					continue Parse
+				}
+			}
+		}
+
+		escSeq := Escaper[d[i]]
+		if escSeq != nil {
+			w.Write(escSeq)
+		} else {
+			w.Write([]byte{d[i]})
+		}
+	}
+}

vendor/github.com/gomarkdown/markdown/html/doc.go

@@ -0,0 +1,43 @@
+/*
+Package html implements HTML renderer of parsed markdown document.
+
+Configuring and customizing a renderer
+
+A renderer can be configured with multiple options:
+
+	import "github.com/gomarkdown/markdown/html"
+
+	flags := html.CommonFlags | html.CompletePage | html.HrefTargetBlank
+	opts := html.RenderOptions{
+		TItle: "A custom title",
+		Flags: flags,
+	}
+	renderer := html.NewRenderer(opts)
+
+You can also re-use most of the logic and customize rendering of selected nodes
+by providing node render hook.
+This is most useful for rendering nodes that allow for design choices, like
+links or code blocks.
+
+	import (
+		"github.com/gomarkdown/markdown/html"
+		"github.com/gomarkdown/markdown/ast"
+	)
+
+	// a very dummy render hook that will output "code_replacements" instead of
+	// <code>${content}</code> emitted by html.Renderer
+	func renderHookCodeBlock(w io.Writer, node *ast.Node, entering bool) (ast.WalkStatus, bool) {
+		_, ok := node.Data.(*ast.CodeBlockData)
+		if !ok {
+			return ast.GoToNext, false
+		}
+		io.WriteString(w, "code_replacement")
+		return ast.GoToNext, true
+	}
+
+	opts := html.RendererOptions{
+		RenderNodeHook: renderHookCodeBlock,
+	}
+	renderer := html.NewRenderer(opts)
+*/
+package html

vendor/github.com/gomarkdown/markdown/html/esc.go

@@ -0,0 +1,50 @@
+package html
+
+import (
+	"html"
+	"io"
+)
+
+var Escaper = [256][]byte{
+	'&': []byte("&"),
+	'<': []byte("&lt;"),
+	'>': []byte("&gt;"),
+	'"': []byte("&quot;"),
+}
+
+// EscapeHTML writes html-escaped d to w. It escapes &, <, > and " characters.
+func EscapeHTML(w io.Writer, d []byte) {
+	var start, end int
+	n := len(d)
+	for end < n {
+		escSeq := Escaper[d[end]]
+		if escSeq != nil {
+			w.Write(d[start:end])
+			w.Write(escSeq)
+			start = end + 1
+		}
+		end++
+	}
+	if start < n && end <= n {
+		w.Write(d[start:end])
+	}
+}
+
+func escLink(w io.Writer, text []byte) {
+	unesc := html.UnescapeString(string(text))
+	EscapeHTML(w, []byte(unesc))
+}
+
+// Escape writes the text to w, but skips the escape character.
+func Escape(w io.Writer, text []byte) {
+	esc := false
+	for i := 0; i < len(text); i++ {
+		if text[i] == '\\' {
+			esc = !esc
+		}
+		if esc && text[i] == '\\' {
+			continue
+		}
+		w.Write([]byte{text[i]})
+	}
+}

vendor/github.com/gomarkdown/markdown/html/smartypants.go

@@ -0,0 +1,444 @@
+package html
+
+import (
+	"bytes"
+	"io"
+)
+
+// SmartyPants rendering
+
+// SPRenderer is a struct containing state of a Smartypants renderer.
+type SPRenderer struct {
+	inSingleQuote bool
+	inDoubleQuote bool
+	callbacks     [256]smartCallback
+}
+
+func wordBoundary(c byte) bool {
+	return c == 0 || isSpace(c) || isPunctuation(c)
+}
+
+func tolower(c byte) byte {
+	if c >= 'A' && c <= 'Z' {
+		return c - 'A' + 'a'
+	}
+	return c
+}
+
+func isdigit(c byte) bool {
+	return c >= '0' && c <= '9'
+}
+
+func smartQuoteHelper(out *bytes.Buffer, previousChar byte, nextChar byte, quote byte, isOpen *bool, addNBSP bool) bool {
+	// edge of the buffer is likely to be a tag that we don't get to see,
+	// so we treat it like text sometimes
+
+	// enumerate all sixteen possibilities for (previousChar, nextChar)
+	// each can be one of {0, space, punct, other}
+	switch {
+	case previousChar == 0 && nextChar == 0:
+		// context is not any help here, so toggle
+		*isOpen = !*isOpen
+	case isSpace(previousChar) && nextChar == 0:
+		// [ "] might be [ "<code>foo...]
+		*isOpen = true
+	case isPunctuation(previousChar) && nextChar == 0:
+		// [!"] hmm... could be [Run!"] or [("<code>...]
+		*isOpen = false
+	case /* isnormal(previousChar) && */ nextChar == 0:
+		// [a"] is probably a close
+		*isOpen = false
+	case previousChar == 0 && isSpace(nextChar):
+		// [" ] might be [...foo</code>" ]
+		*isOpen = false
+	case isSpace(previousChar) && isSpace(nextChar):
+		// [ " ] context is not any help here, so toggle
+		*isOpen = !*isOpen
+	case isPunctuation(previousChar) && isSpace(nextChar):
+		// [!" ] is probably a close
+		*isOpen = false
+	case /* isnormal(previousChar) && */ isSpace(nextChar):
+		// [a" ] this is one of the easy cases
+		*isOpen = false
+	case previousChar == 0 && isPunctuation(nextChar):
+		// ["!] hmm... could be ["$1.95] or [</code>"!...]
+		*isOpen = false
+	case isSpace(previousChar) && isPunctuation(nextChar):
+		// [ "!] looks more like [ "$1.95]
+		*isOpen = true
+	case isPunctuation(previousChar) && isPunctuation(nextChar):
+		// [!"!] context is not any help here, so toggle
+		*isOpen = !*isOpen
+	case /* isnormal(previousChar) && */ isPunctuation(nextChar):
+		// [a"!] is probably a close
+		*isOpen = false
+	case previousChar == 0 /* && isnormal(nextChar) */ :
+		// ["a] is probably an open
+		*isOpen = true
+	case isSpace(previousChar) /* && isnormal(nextChar) */ :
+		// [ "a] this is one of the easy cases
+		*isOpen = true
+	case isPunctuation(previousChar) /* && isnormal(nextChar) */ :
+		// [!"a] is probably an open
+		*isOpen = true
+	default:
+		// [a'b] maybe a contraction?
+		*isOpen = false
+	}
+
+	// Note that with the limited lookahead, this non-breaking
+	// space will also be appended to single double quotes.
+	if addNBSP && !*isOpen {
+		out.WriteString("&nbsp;")
+	}
+
+	out.WriteByte('&')
+	if *isOpen {
+		out.WriteByte('l')
+	} else {
+		out.WriteByte('r')
+	}
+	out.WriteByte(quote)
+	out.WriteString("quo;")
+
+	if addNBSP && *isOpen {
+		out.WriteString("&nbsp;")
+	}
+
+	return true
+}
+
+func (r *SPRenderer) smartSingleQuote(out *bytes.Buffer, previousChar byte, text []byte) int {
+	if len(text) >= 2 {
+		t1 := tolower(text[1])
+
+		if t1 == '\'' {
+			nextChar := byte(0)
+			if len(text) >= 3 {
+				nextChar = text[2]
+			}
+			if smartQuoteHelper(out, previousChar, nextChar, 'd', &r.inDoubleQuote, false) {
+				return 1
+			}
+		}
+
+		if (t1 == 's' || t1 == 't' || t1 == 'm' || t1 == 'd') && (len(text) < 3 || wordBoundary(text[2])) {
+			out.WriteString("&rsquo;")
+			return 0
+		}
+
+		if len(text) >= 3 {
+			t2 := tolower(text[2])
+
+			if ((t1 == 'r' && t2 == 'e') || (t1 == 'l' && t2 == 'l') || (t1 == 'v' && t2 == 'e')) &&
+				(len(text) < 4 || wordBoundary(text[3])) {
+				out.WriteString("&rsquo;")
+				return 0
+			}
+		}
+	}
+
+	nextChar := byte(0)
+	if len(text) > 1 {
+		nextChar = text[1]
+	}
+	if smartQuoteHelper(out, previousChar, nextChar, 's', &r.inSingleQuote, false) {
+		return 0
+	}
+
+	out.WriteByte(text[0])
+	return 0
+}
+
+func (r *SPRenderer) smartParens(out *bytes.Buffer, previousChar byte, text []byte) int {
+	if len(text) >= 3 {
+		t1 := tolower(text[1])
+		t2 := tolower(text[2])
+
+		if t1 == 'c' && t2 == ')' {
+			out.WriteString("&copy;")
+			return 2
+		}
+
+		if t1 == 'r' && t2 == ')' {
+			out.WriteString("&reg;")
+			return 2
+		}
+
+		if len(text) >= 4 && t1 == 't' && t2 == 'm' && text[3] == ')' {
+			out.WriteString("&trade;")
+			return 3
+		}
+	}
+
+	out.WriteByte(text[0])
+	return 0
+}
+
+func (r *SPRenderer) smartDash(out *bytes.Buffer, previousChar byte, text []byte) int {
+	if len(text) >= 2 {
+		if text[1] == '-' {
+			out.WriteString("&mdash;")
+			return 1
+		}
+
+		if wordBoundary(previousChar) && wordBoundary(text[1]) {
+			out.WriteString("&ndash;")
+			return 0
+		}
+	}
+
+	out.WriteByte(text[0])
+	return 0
+}
+
+func (r *SPRenderer) smartDashLatex(out *bytes.Buffer, previousChar byte, text []byte) int {
+	if len(text) >= 3 && text[1] == '-' && text[2] == '-' {
+		out.WriteString("&mdash;")
+		return 2
+	}
+	if len(text) >= 2 && text[1] == '-' {
+		out.WriteString("&ndash;")
+		return 1
+	}
+
+	out.WriteByte(text[0])
+	return 0
+}
+
+func (r *SPRenderer) smartAmpVariant(out *bytes.Buffer, previousChar byte, text []byte, quote byte, addNBSP bool) int {
+	if bytes.HasPrefix(text, []byte("&quot;")) {
+		nextChar := byte(0)
+		if len(text) >= 7 {
+			nextChar = text[6]
+		}
+		if smartQuoteHelper(out, previousChar, nextChar, quote, &r.inDoubleQuote, addNBSP) {
+			return 5
+		}
+	}
+
+	if bytes.HasPrefix(text, []byte("&#0;")) {
+		return 3
+	}
+
+	out.WriteByte('&')
+	return 0
+}
+
+func (r *SPRenderer) smartAmp(angledQuotes, addNBSP bool) func(*bytes.Buffer, byte, []byte) int {
+	var quote byte = 'd'
+	if angledQuotes {
+		quote = 'a'
+	}
+
+	return func(out *bytes.Buffer, previousChar byte, text []byte) int {
+		return r.smartAmpVariant(out, previousChar, text, quote, addNBSP)
+	}
+}
+
+func (r *SPRenderer) smartPeriod(out *bytes.Buffer, previousChar byte, text []byte) int {
+	if len(text) >= 3 && text[1] == '.' && text[2] == '.' {
+		out.WriteString("&hellip;")
+		return 2
+	}
+
+	if len(text) >= 5 && text[1] == ' ' && text[2] == '.' && text[3] == ' ' && text[4] == '.' {
+		out.WriteString("&hellip;")
+		return 4
+	}
+
+	out.WriteByte(text[0])
+	return 0
+}
+
+func (r *SPRenderer) smartBacktick(out *bytes.Buffer, previousChar byte, text []byte) int {
+	if len(text) >= 2 && text[1] == '`' {
+		nextChar := byte(0)
+		if len(text) >= 3 {
+			nextChar = text[2]
+		}
+		if smartQuoteHelper(out, previousChar, nextChar, 'd', &r.inDoubleQuote, false) {
+			return 1
+		}
+	}
+
+	out.WriteByte(text[0])
+	return 0
+}
+
+func (r *SPRenderer) smartNumberGeneric(out *bytes.Buffer, previousChar byte, text []byte) int {
+	if wordBoundary(previousChar) && previousChar != '/' && len(text) >= 3 {
+		// is it of the form digits/digits(word boundary)?, i.e., \d+/\d+\b
+		// note: check for regular slash (/) or fraction slash (⁄, 0x2044, or 0xe2 81 84 in utf-8)
+		//       and avoid changing dates like 1/23/2005 into fractions.
+		numEnd := 0
+		for len(text) > numEnd && isdigit(text[numEnd]) {
+			numEnd++
+		}
+		if numEnd == 0 {
+			out.WriteByte(text[0])
+			return 0
+		}
+		denStart := numEnd + 1
+		if len(text) > numEnd+3 && text[numEnd] == 0xe2 && text[numEnd+1] == 0x81 && text[numEnd+2] == 0x84 {
+			denStart = numEnd + 3
+		} else if len(text) < numEnd+2 || text[numEnd] != '/' {
+			out.WriteByte(text[0])
+			return 0
+		}
+		denEnd := denStart
+		for len(text) > denEnd && isdigit(text[denEnd]) {
+			denEnd++
+		}
+		if denEnd == denStart {
+			out.WriteByte(text[0])
+			return 0
+		}
+		if len(text) == denEnd || wordBoundary(text[denEnd]) && text[denEnd] != '/' {
+			out.WriteString("<sup>")
+			out.Write(text[:numEnd])
+			out.WriteString("</sup>&frasl;<sub>")
+			out.Write(text[denStart:denEnd])
+			out.WriteString("</sub>")
+			return denEnd - 1
+		}
+	}
+
+	out.WriteByte(text[0])
+	return 0
+}
+
+func (r *SPRenderer) smartNumber(out *bytes.Buffer, previousChar byte, text []byte) int {
+	if wordBoundary(previousChar) && previousChar != '/' && len(text) >= 3 {
+		if text[0] == '1' && text[1] == '/' && text[2] == '2' {
+			if len(text) < 4 || wordBoundary(text[3]) && text[3] != '/' {
+				out.WriteString("&frac12;")
+				return 2
+			}
+		}
+
+		if text[0] == '1' && text[1] == '/' && text[2] == '4' {
+			if len(text) < 4 || wordBoundary(text[3]) && text[3] != '/' || (len(text) >= 5 && tolower(text[3]) == 't' && tolower(text[4]) == 'h') {
+				out.WriteString("&frac14;")
+				return 2
+			}
+		}
+
+		if text[0] == '3' && text[1] == '/' && text[2] == '4' {
+			if len(text) < 4 || wordBoundary(text[3]) && text[3] != '/' || (len(text) >= 6 && tolower(text[3]) == 't' && tolower(text[4]) == 'h' && tolower(text[5]) == 's') {
+				out.WriteString("&frac34;")
+				return 2
+			}
+		}
+	}
+
+	out.WriteByte(text[0])
+	return 0
+}
+
+func (r *SPRenderer) smartDoubleQuoteVariant(out *bytes.Buffer, previousChar byte, text []byte, quote byte) int {
+	nextChar := byte(0)
+	if len(text) > 1 {
+		nextChar = text[1]
+	}
+	if !smartQuoteHelper(out, previousChar, nextChar, quote, &r.inDoubleQuote, false) {
+		out.WriteString("&quot;")
+	}
+
+	return 0
+}
+
+func (r *SPRenderer) smartDoubleQuote(out *bytes.Buffer, previousChar byte, text []byte) int {
+	return r.smartDoubleQuoteVariant(out, previousChar, text, 'd')
+}
+
+func (r *SPRenderer) smartAngledDoubleQuote(out *bytes.Buffer, previousChar byte, text []byte) int {
+	return r.smartDoubleQuoteVariant(out, previousChar, text, 'a')
+}
+
+func (r *SPRenderer) smartLeftAngle(out *bytes.Buffer, previousChar byte, text []byte) int {
+	i := 0
+
+	for i < len(text) && text[i] != '>' {
+		i++
+	}
+
+	out.Write(text[:i+1])
+	return i
+}
+
+type smartCallback func(out *bytes.Buffer, previousChar byte, text []byte) int
+
+// NewSmartypantsRenderer constructs a Smartypants renderer object.
+func NewSmartypantsRenderer(flags Flags) *SPRenderer {
+	var (
+		r SPRenderer
+
+		smartAmpAngled      = r.smartAmp(true, false)
+		smartAmpAngledNBSP  = r.smartAmp(true, true)
+		smartAmpRegular     = r.smartAmp(false, false)
+		smartAmpRegularNBSP = r.smartAmp(false, true)
+
+		addNBSP = flags&SmartypantsQuotesNBSP != 0
+	)
+
+	if flags&SmartypantsAngledQuotes == 0 {
+		r.callbacks['"'] = r.smartDoubleQuote
+		if !addNBSP {
+			r.callbacks['&'] = smartAmpRegular
+		} else {
+			r.callbacks['&'] = smartAmpRegularNBSP
+		}
+	} else {
+		r.callbacks['"'] = r.smartAngledDoubleQuote
+		if !addNBSP {
+			r.callbacks['&'] = smartAmpAngled
+		} else {
+			r.callbacks['&'] = smartAmpAngledNBSP
+		}
+	}
+	r.callbacks['\''] = r.smartSingleQuote
+	r.callbacks['('] = r.smartParens
+	if flags&SmartypantsDashes != 0 {
+		if flags&SmartypantsLatexDashes == 0 {
+			r.callbacks['-'] = r.smartDash
+		} else {
+			r.callbacks['-'] = r.smartDashLatex
+		}
+	}
+	r.callbacks['.'] = r.smartPeriod
+	if flags&SmartypantsFractions == 0 {
+		r.callbacks['1'] = r.smartNumber
+		r.callbacks['3'] = r.smartNumber
+	} else {
+		for ch := '1'; ch <= '9'; ch++ {
+			r.callbacks[ch] = r.smartNumberGeneric
+		}
+	}
+	r.callbacks['<'] = r.smartLeftAngle
+	r.callbacks['`'] = r.smartBacktick
+	return &r
+}
+
+// Process is the entry point of the Smartypants renderer.
+func (r *SPRenderer) Process(w io.Writer, text []byte) {
+	mark := 0
+	for i := 0; i < len(text); i++ {
+		if action := r.callbacks[text[i]]; action != nil {
+			if i > mark {
+				w.Write(text[mark:i])
+			}
+			previousChar := byte(0)
+			if i > 0 {
+				previousChar = text[i-1]
+			}
+			var tmp bytes.Buffer
+			i += action(&tmp, previousChar, text[i:])
+			w.Write(tmp.Bytes())
+			mark = i + 1
+		}
+	}
+	if mark < len(text) {
+		w.Write(text[mark:])
+	}
+}