go1.16 (#14783)

vendor/github.com/russross/blackfriday/v2/README.md

@@ -1,4 +1,6 @@
-Blackfriday [![Build Status](https://travis-ci.org/russross/blackfriday.svg?branch=master)](https://travis-ci.org/russross/blackfriday)
+Blackfriday
+[![Build Status][BuildV2SVG]][BuildV2URL]
+[![PkgGoDev][PkgGoDevV2SVG]][PkgGoDevV2URL]
 ===========
 
 Blackfriday is a [Markdown][1] processor implemented in [Go][2]. It
@@ -16,19 +18,21 @@ It started as a translation from C of [Sundown][3].
 Installation
 ------------
 
-Blackfriday is compatible with any modern Go release. With Go 1.7 and git
-installed:
+Blackfriday is compatible with modern Go releases in module mode.
+With Go installed:
 
-    go get gopkg.in/russross/blackfriday.v2
+    go get github.com/russross/blackfriday/v2
 
-will download, compile, and install the package into your `$GOPATH`
-directory hierarchy. Alternatively, you can achieve the same if you
-import it into a project:
+will resolve and add the package to the current development module,
+then build and install it. Alternatively, you can achieve the same
+if you import it in a package:
 
-    import "gopkg.in/russross/blackfriday.v2"
+    import "github.com/russross/blackfriday/v2"
 
 and `go get` without parameters.
 
+Legacy GOPATH mode is unsupported.
+
 
 Versions
 --------
@@ -36,13 +40,9 @@ Versions
 Currently maintained and recommended version of Blackfriday is `v2`. It's being
 developed on its own branch: https://github.com/russross/blackfriday/tree/v2 and the
 documentation is available at
-https://godoc.org/gopkg.in/russross/blackfriday.v2.
+https://pkg.go.dev/github.com/russross/blackfriday/v2.
 
-It is `go get`-able via via [gopkg.in][6] at `gopkg.in/russross/blackfriday.v2`,
-but we highly recommend using package management tool like [dep][7] or
-[Glide][8] and make use of semantic versioning. With package management you
-should import `github.com/russross/blackfriday` and specify that you're using
-version 2.0.0.
+It is `go get`-able in module mode at `github.com/russross/blackfriday/v2`.
 
 Version 2 offers a number of improvements over v1:
 
@@ -62,6 +62,11 @@ Potential drawbacks:
   v2. See issue [#348](https://github.com/russross/blackfriday/issues/348) for
   tracking.
 
+If you are still interested in the legacy `v1`, you can import it from
+`github.com/russross/blackfriday`. Documentation for the legacy v1 can be found
+here: https://pkg.go.dev/github.com/russross/blackfriday.
+
+
 Usage
 -----
 
@@ -91,7 +96,7 @@ Here's an example of simple usage of Blackfriday together with Bluemonday:
 ```go
 import (
     "github.com/microcosm-cc/bluemonday"
-    "github.com/russross/blackfriday"
+    "github.com/russross/blackfriday/v2"
 )
 
 // ...
@@ -104,6 +109,8 @@ html := bluemonday.UGCPolicy().SanitizeBytes(unsafe)
 If you want to customize the set of options, use `blackfriday.WithExtensions`,
 `blackfriday.WithRenderer` and `blackfriday.WithRefOverride`.
 
+### `blackfriday-tool`
+
 You can also check out `blackfriday-tool` for a more complete example
 of how to use it. Download and install it using:
 
@@ -114,7 +121,7 @@ markdown file using a standalone program.  You can also browse the
 source directly on github if you are just looking for some example
 code:
 
-* <http://github.com/russross/blackfriday-tool>
+* <https://github.com/russross/blackfriday-tool>
 
 Note that if you have not already done so, installing
 `blackfriday-tool` will be sufficient to download and install
@@ -123,6 +130,22 @@ installed in `$GOPATH/bin`.  This is a statically-linked binary that
 can be copied to wherever you need it without worrying about
 dependencies and library versions.
 
+### Sanitized anchor names
+
+Blackfriday includes an algorithm for creating sanitized anchor names
+corresponding to a given input text. This algorithm is used to create
+anchors for headings when `AutoHeadingIDs` extension is enabled. The
+algorithm has a specification, so that other packages can create
+compatible anchor names and links to those anchors.
+
+The specification is located at https://pkg.go.dev/github.com/russross/blackfriday/v2#hdr-Sanitized_Anchor_Names.
+
+[`SanitizedAnchorName`](https://pkg.go.dev/github.com/russross/blackfriday/v2#SanitizedAnchorName) exposes this functionality, and can be used to
+create compatible links to the anchor names generated by blackfriday.
+This algorithm is also implemented in a small standalone package at
+[`github.com/shurcooL/sanitized_anchor_name`](https://pkg.go.dev/github.com/shurcooL/sanitized_anchor_name). It can be useful for clients
+that want a small package and don't need full functionality of blackfriday.
+
 
 Features
 --------
@@ -199,6 +222,15 @@ implements the following extensions:
     You can use 3 or more backticks to mark the beginning of the
     block, and the same number to mark the end of the block.
 
+    To preserve classes of fenced code blocks while using the bluemonday
+    HTML sanitizer, use the following policy:
+
+    ```go
+    p := bluemonday.UGCPolicy()
+    p.AllowAttrs("class").Matching(regexp.MustCompile("^language-[a-zA-Z0-9]+$")).OnElements("code")
+    html := p.SanitizeBytes(unsafe)
+    ```
+
 *   **Definition lists**. A simple definition list is made of a single-line
     term followed by a colon and the definition for that term.
 
@@ -250,7 +282,7 @@ Other renderers
 Blackfriday is structured to allow alternative rendering engines. Here
 are a few of note:
 
-*   [github_flavored_markdown](https://godoc.org/github.com/shurcooL/github_flavored_markdown):
+*   [github_flavored_markdown](https://pkg.go.dev/github.com/shurcooL/github_flavored_markdown):
     provides a GitHub Flavored Markdown renderer with fenced code block
     highlighting, clickable heading anchor links.
 
@@ -261,20 +293,28 @@ are a few of note:
 *   [markdownfmt](https://github.com/shurcooL/markdownfmt): like gofmt,
     but for markdown.
 
-*   [LaTeX output](https://github.com/Ambrevar/Blackfriday-LaTeX):
+*   [LaTeX output](https://gitlab.com/ambrevar/blackfriday-latex):
     renders output as LaTeX.
 
+*   [bfchroma](https://github.com/Depado/bfchroma/): provides convenience
+    integration with the [Chroma](https://github.com/alecthomas/chroma) code
+    highlighting library. bfchroma is only compatible with v2 of Blackfriday and
+    provides a drop-in renderer ready to use with Blackfriday, as well as
+    options and means for further customization.
+
 *   [Blackfriday-Confluence](https://github.com/kentaro-m/blackfriday-confluence): provides a [Confluence Wiki Markup](https://confluence.atlassian.com/doc/confluence-wiki-markup-251003035.html) renderer.
 
+*   [Blackfriday-Slack](https://github.com/karriereat/blackfriday-slack): converts markdown to slack message style
 
-Todo
+
+TODO
 ----
 
 *   More unit testing
-*   Improve unicode support. It does not understand all unicode
+*   Improve Unicode support. It does not understand all Unicode
     rules (about what constitutes a letter, a punctuation symbol,
     etc.), so it may fail to detect word boundaries correctly in
-    some instances. It is safe on all utf-8 input.
+    some instances. It is safe on all UTF-8 input.
 
 
 License
@@ -286,6 +326,10 @@ License
    [1]: https://daringfireball.net/projects/markdown/ "Markdown"
    [2]: https://golang.org/ "Go Language"
    [3]: https://github.com/vmg/sundown "Sundown"
-   [4]: https://godoc.org/gopkg.in/russross/blackfriday.v2#Parse "Parse func"
+   [4]: https://pkg.go.dev/github.com/russross/blackfriday/v2#Parse "Parse func"
    [5]: https://github.com/microcosm-cc/bluemonday "Bluemonday"
-   [6]: https://labix.org/gopkg.in "gopkg.in"
+
+   [BuildV2SVG]: https://travis-ci.org/russross/blackfriday.svg?branch=v2
+   [BuildV2URL]: https://travis-ci.org/russross/blackfriday
+   [PkgGoDevV2SVG]: https://pkg.go.dev/badge/github.com/russross/blackfriday/v2
+   [PkgGoDevV2URL]: https://pkg.go.dev/github.com/russross/blackfriday/v2

vendor/github.com/russross/blackfriday/v2/block.go

@@ -18,8 +18,7 @@ import (
 	"html"
 	"regexp"
 	"strings"
-
-	"github.com/shurcooL/sanitized_anchor_name"
+	"unicode"
 )
 
 const (
@@ -259,7 +258,7 @@ func (p *Markdown) prefixHeading(data []byte) int {
 	}
 	if end > i {
 		if id == "" && p.extensions&AutoHeadingIDs != 0 {
-			id = sanitized_anchor_name.Create(string(data[i:end]))
+			id = SanitizedAnchorName(string(data[i:end]))
 		}
 		block := p.addBlock(Heading, data[i:end])
 		block.HeadingID = id
@@ -673,6 +672,7 @@ func (p *Markdown) fencedCodeBlock(data []byte, doRender bool) int {
 	if beg == 0 || beg >= len(data) {
 		return 0
 	}
+	fenceLength := beg - 1
 
 	var work bytes.Buffer
 	work.Write([]byte(info))
@@ -706,6 +706,7 @@ func (p *Markdown) fencedCodeBlock(data []byte, doRender bool) int {
 	if doRender {
 		block := p.addBlock(CodeBlock, work.Bytes()) // TODO: get rid of temp buffer
 		block.IsFenced = true
+		block.FenceLength = fenceLength
 		finalizeCodeBlock(block)
 	}
 
@@ -1503,7 +1504,7 @@ func (p *Markdown) paragraph(data []byte) int {
 
 				id := ""
 				if p.extensions&AutoHeadingIDs != 0 {
-					id = sanitized_anchor_name.Create(string(data[prev:eol]))
+					id = SanitizedAnchorName(string(data[prev:eol]))
 				}
 
 				block := p.addBlock(Heading, data[prev:eol])
@@ -1588,3 +1589,24 @@ func skipUntilChar(text []byte, start int, char byte) int {
 	}
 	return i
 }
+
+// SanitizedAnchorName returns a sanitized anchor name for the given text.
+//
+// It implements the algorithm specified in the package comment.
+func SanitizedAnchorName(text string) string {
+	var anchorName []rune
+	futureDash := false
+	for _, r := range text {
+		switch {
+		case unicode.IsLetter(r) || unicode.IsNumber(r):
+			if futureDash && len(anchorName) > 0 {
+				anchorName = append(anchorName, '-')
+			}
+			futureDash = false
+			anchorName = append(anchorName, unicode.ToLower(r))
+		default:
+			futureDash = true
+		}
+	}
+	return string(anchorName)
+}

vendor/github.com/russross/blackfriday/v2/doc.go

@@ -15,4 +15,32 @@
 //
 // If you're interested in calling Blackfriday from command line, see
 // https://github.com/russross/blackfriday-tool.
+//
+// Sanitized Anchor Names
+//
+// Blackfriday includes an algorithm for creating sanitized anchor names
+// corresponding to a given input text. This algorithm is used to create
+// anchors for headings when AutoHeadingIDs extension is enabled. The
+// algorithm is specified below, so that other packages can create
+// compatible anchor names and links to those anchors.
+//
+// The algorithm iterates over the input text, interpreted as UTF-8,
+// one Unicode code point (rune) at a time. All runes that are letters (category L)
+// or numbers (category N) are considered valid characters. They are mapped to
+// lower case, and included in the output. All other runes are considered
+// invalid characters. Invalid characters that precede the first valid character,
+// as well as invalid character that follow the last valid character
+// are dropped completely. All other sequences of invalid characters
+// between two valid characters are replaced with a single dash character '-'.
+//
+// SanitizedAnchorName exposes this functionality, and can be used to
+// create compatible links to the anchor names generated by blackfriday.
+// This algorithm is also implemented in a small standalone package at
+// github.com/shurcooL/sanitized_anchor_name. It can be useful for clients
+// that want a small package and don't need full functionality of blackfriday.
 package blackfriday
+
+// NOTE: Keep Sanitized Anchor Name algorithm in sync with package
+//       github.com/shurcooL/sanitized_anchor_name.
+//       Otherwise, users of sanitized_anchor_name will get anchor names
+//       that are incompatible with those generated by blackfriday.

vendor/github.com/russross/blackfriday/v2/esc.go

@@ -13,13 +13,27 @@ var htmlEscaper = [256][]byte{
 }
 
 func escapeHTML(w io.Writer, s []byte) {
+	escapeEntities(w, s, false)
+}
+
+func escapeAllHTML(w io.Writer, s []byte) {
+	escapeEntities(w, s, true)
+}
+
+func escapeEntities(w io.Writer, s []byte, escapeValidEntities bool) {
 	var start, end int
 	for end < len(s) {
 		escSeq := htmlEscaper[s[end]]
 		if escSeq != nil {
-			w.Write(s[start:end])
-			w.Write(escSeq)
-			start = end + 1
+			isEntity, entityEnd := nodeIsEntity(s, end)
+			if isEntity && !escapeValidEntities {
+				w.Write(s[start : entityEnd+1])
+				start = entityEnd + 1
+			} else {
+				w.Write(s[start:end])
+				w.Write(escSeq)
+				start = end + 1
+			}
 		}
 		end++
 	}
@@ -28,6 +42,28 @@ func escapeHTML(w io.Writer, s []byte) {
 	}
 }
 
+func nodeIsEntity(s []byte, end int) (isEntity bool, endEntityPos int) {
+	isEntity = false
+	endEntityPos = end + 1
+
+	if s[end] == '&' {
+		for endEntityPos < len(s) {
+			if s[endEntityPos] == ';' {
+				if entities[string(s[end:endEntityPos+1])] {
+					isEntity = true
+					break
+				}
+			}
+			if !isalnum(s[endEntityPos]) && s[endEntityPos] != '&' && s[endEntityPos] != '#' {
+				break
+			}
+			endEntityPos++
+		}
+	}
+
+	return isEntity, endEntityPos
+}
+
 func escLink(w io.Writer, text []byte) {
 	unesc := html.UnescapeString(string(text))
 	escapeHTML(w, []byte(unesc))

vendor/github.com/russross/blackfriday/v2/html.go

@@ -132,7 +132,10 @@ func NewHTMLRenderer(params HTMLRendererParameters) *HTMLRenderer {
 	}
 
 	if params.FootnoteReturnLinkContents == "" {
-		params.FootnoteReturnLinkContents = `<sup>[return]</sup>`
+		// U+FE0E is VARIATION SELECTOR-15.
+		// It suppresses automatic emoji presentation of the preceding
+		// U+21A9 LEFTWARDS ARROW WITH HOOK on iOS and iPadOS.
+		params.FootnoteReturnLinkContents = "<span aria-label='Return'>↩\ufe0e</span>"
 	}
 
 	return &HTMLRenderer{
@@ -616,7 +619,7 @@ func (r *HTMLRenderer) RenderNode(w io.Writer, node *Node, entering bool) WalkSt
 		}
 	case Code:
 		r.out(w, codeTag)
-		escapeHTML(w, node.Literal)
+		escapeAllHTML(w, node.Literal)
 		r.out(w, codeCloseTag)
 	case Document:
 		break
@@ -762,7 +765,7 @@ func (r *HTMLRenderer) RenderNode(w io.Writer, node *Node, entering bool) WalkSt
 		r.cr(w)
 		r.out(w, preTag)
 		r.tag(w, codeTag[:len(codeTag)-1], attrs)
-		escapeHTML(w, node.Literal)
+		escapeAllHTML(w, node.Literal)
 		r.out(w, codeCloseTag)
 		r.out(w, preCloseTag)
 		if node.Parent.Type != Item {

vendor/github.com/russross/blackfriday/v2/inline.go

@@ -278,7 +278,7 @@ func link(p *Markdown, data []byte, offset int) (int, *Node) {
 		case data[i] == '\n':
 			textHasNl = true
 
-		case data[i-1] == '\\':
+		case isBackslashEscaped(data, i):
 			continue
 
 		case data[i] == '[':

vendor/github.com/russross/blackfriday/v2/node.go

@@ -199,7 +199,8 @@ func (n *Node) InsertBefore(sibling *Node) {
 	}
 }
 
-func (n *Node) isContainer() bool {
+// IsContainer returns true if 'n' can contain children.
+func (n *Node) IsContainer() bool {
 	switch n.Type {
 	case Document:
 		fallthrough
@@ -238,6 +239,11 @@ func (n *Node) isContainer() bool {
 	}
 }
 
+// IsLeaf returns true if 'n' is a leaf node.
+func (n *Node) IsLeaf() bool {
+	return !n.IsContainer()
+}
+
 func (n *Node) canContain(t NodeType) bool {
 	if n.Type == List {
 		return t == Item
@@ -309,11 +315,11 @@ func newNodeWalker(root *Node) *nodeWalker {
 }
 
 func (nw *nodeWalker) next() {
-	if (!nw.current.isContainer() || !nw.entering) && nw.current == nw.root {
+	if (!nw.current.IsContainer() || !nw.entering) && nw.current == nw.root {
 		nw.current = nil
 		return
 	}
-	if nw.entering && nw.current.isContainer() {
+	if nw.entering && nw.current.IsContainer() {
 		if nw.current.FirstChild != nil {
 			nw.current = nw.current.FirstChild
 			nw.entering = true