1 files changed, 339 insertions, 0 deletions
diff --git a/vendor/github.com/yuin/goldmark/extension/typographer.go b/vendor/github.com/yuin/goldmark/extension/typographer.go
new file mode 100644
index 000000000..f56c06f74
--- /dev/null
+++ b/vendor/github.com/yuin/goldmark/extension/typographer.go
@@ -0,0 +1,339 @@
+package extension
+
+import (
+	"unicode"
+
+	"github.com/yuin/goldmark"
+	gast "github.com/yuin/goldmark/ast"
+	"github.com/yuin/goldmark/parser"
+	"github.com/yuin/goldmark/text"
+	"github.com/yuin/goldmark/util"
+)
+
+var uncloseCounterKey = parser.NewContextKey()
+
+type unclosedCounter struct {
+	Single int
+	Double int
+}
+
+func (u *unclosedCounter) Reset() {
+	u.Single = 0
+	u.Double = 0
+}
+
+func getUnclosedCounter(pc parser.Context) *unclosedCounter {
+	v := pc.Get(uncloseCounterKey)
+	if v == nil {
+		v = &unclosedCounter{}
+		pc.Set(uncloseCounterKey, v)
+	}
+	return v.(*unclosedCounter)
+}
+
+// TypographicPunctuation is a key of the punctuations that can be replaced with
+// typographic entities.
+type TypographicPunctuation int
+
+const (
+	// LeftSingleQuote is '
+	LeftSingleQuote TypographicPunctuation = iota + 1
+	// RightSingleQuote is '
+	RightSingleQuote
+	// LeftDoubleQuote is "
+	LeftDoubleQuote
+	// RightDoubleQuote is "
+	RightDoubleQuote
+	// EnDash is --
+	EnDash
+	// EmDash is ---
+	EmDash
+	// Ellipsis is ...
+	Ellipsis
+	// LeftAngleQuote is <<
+	LeftAngleQuote
+	// RightAngleQuote is >>
+	RightAngleQuote
+	// Apostrophe is '
+	Apostrophe
+
+	typographicPunctuationMax
+)
+
+// An TypographerConfig struct is a data structure that holds configuration of the
+// Typographer extension.
+type TypographerConfig struct {
+	Substitutions [][]byte
+}
+
+func newDefaultSubstitutions() [][]byte {
+	replacements := make([][]byte, typographicPunctuationMax)
+	replacements[LeftSingleQuote] = []byte("&lsquo;")
+	replacements[RightSingleQuote] = []byte("&rsquo;")
+	replacements[LeftDoubleQuote] = []byte("&ldquo;")
+	replacements[RightDoubleQuote] = []byte("&rdquo;")
+	replacements[EnDash] = []byte("&ndash;")
+	replacements[EmDash] = []byte("&mdash;")
+	replacements[Ellipsis] = []byte("&hellip;")
+	replacements[LeftAngleQuote] = []byte("&laquo;")
+	replacements[RightAngleQuote] = []byte("&raquo;")
+	replacements[Apostrophe] = []byte("&rsquo;")
+
+	return replacements
+}
+
+// SetOption implements SetOptioner.
+func (b *TypographerConfig) SetOption(name parser.OptionName, value interface{}) {
+	switch name {
+	case optTypographicSubstitutions:
+		b.Substitutions = value.([][]byte)
+	}
+}
+
+// A TypographerOption interface sets options for the TypographerParser.
+type TypographerOption interface {
+	parser.Option
+	SetTypographerOption(*TypographerConfig)
+}
+
+const optTypographicSubstitutions parser.OptionName = "TypographicSubstitutions"
+
+// TypographicSubstitutions is a list of the substitutions for the Typographer extension.
+type TypographicSubstitutions map[TypographicPunctuation][]byte
+
+type withTypographicSubstitutions struct {
+	value [][]byte
+}
+
+func (o *withTypographicSubstitutions) SetParserOption(c *parser.Config) {
+	c.Options[optTypographicSubstitutions] = o.value
+}
+
+func (o *withTypographicSubstitutions) SetTypographerOption(p *TypographerConfig) {
+	p.Substitutions = o.value
+}
+
+// WithTypographicSubstitutions is a functional otpion that specify replacement text
+// for punctuations.
+func WithTypographicSubstitutions(values map[TypographicPunctuation][]byte) TypographerOption {
+	replacements := newDefaultSubstitutions()
+	for k, v := range values {
+		replacements[k] = v
+	}
+
+	return &withTypographicSubstitutions{replacements}
+}
+
+type typographerDelimiterProcessor struct {
+}
+
+func (p *typographerDelimiterProcessor) IsDelimiter(b byte) bool {
+	return b == '\'' || b == '"'
+}
+
+func (p *typographerDelimiterProcessor) CanOpenCloser(opener, closer *parser.Delimiter) bool {
+	return opener.Char == closer.Char
+}
+
+func (p *typographerDelimiterProcessor) OnMatch(consumes int) gast.Node {
+	return nil
+}
+
+var defaultTypographerDelimiterProcessor = &typographerDelimiterProcessor{}
+
+type typographerParser struct {
+	TypographerConfig
+}
+
+// NewTypographerParser return a new InlineParser that parses
+// typographer expressions.
+func NewTypographerParser(opts ...TypographerOption) parser.InlineParser {
+	p := &typographerParser{
+		TypographerConfig: TypographerConfig{
+			Substitutions: newDefaultSubstitutions(),
+		},
+	}
+	for _, o := range opts {
+		o.SetTypographerOption(&p.TypographerConfig)
+	}
+	return p
+}
+
+func (s *typographerParser) Trigger() []byte {
+	return []byte{'\'', '"', '-', '.', ',', '<', '>', '*', '['}
+}
+
+func (s *typographerParser) Parse(parent gast.Node, block text.Reader, pc parser.Context) gast.Node {
+	line, _ := block.PeekLine()
+	c := line[0]
+	if len(line) > 2 {
+		if c == '-' {
+			if s.Substitutions[EmDash] != nil && line[1] == '-' && line[2] == '-' { // ---
+				node := gast.NewString(s.Substitutions[EmDash])
+				node.SetCode(true)
+				block.Advance(3)
+				return node
+			}
+		} else if c == '.' {
+			if s.Substitutions[Ellipsis] != nil && line[1] == '.' && line[2] == '.' { // ...
+				node := gast.NewString(s.Substitutions[Ellipsis])
+				node.SetCode(true)
+				block.Advance(3)
+				return node
+			}
+			return nil
+		}
+	}
+	if len(line) > 1 {
+		if c == '<' {
+			if s.Substitutions[LeftAngleQuote] != nil && line[1] == '<' { // <<
+				node := gast.NewString(s.Substitutions[LeftAngleQuote])
+				node.SetCode(true)
+				block.Advance(2)
+				return node
+			}
+			return nil
+		} else if c == '>' {
+			if s.Substitutions[RightAngleQuote] != nil && line[1] == '>' { // >>
+				node := gast.NewString(s.Substitutions[RightAngleQuote])
+				node.SetCode(true)
+				block.Advance(2)
+				return node
+			}
+			return nil
+		} else if s.Substitutions[EnDash] != nil && c == '-' && line[1] == '-' { // --
+			node := gast.NewString(s.Substitutions[EnDash])
+			node.SetCode(true)
+			block.Advance(2)
+			return node
+		}
+	}
+	if c == '\'' || c == '"' {
+		before := block.PrecendingCharacter()
+		d := parser.ScanDelimiter(line, before, 1, defaultTypographerDelimiterProcessor)
+		if d == nil {
+			return nil
+		}
+		counter := getUnclosedCounter(pc)
+		if c == '\'' {
+			if s.Substitutions[Apostrophe] != nil {
+				// Handle decade abbrevations such as '90s
+				if d.CanOpen && !d.CanClose && len(line) > 3 && util.IsNumeric(line[1]) && util.IsNumeric(line[2]) && line[3] == 's' {
+					after := rune(' ')
+					if len(line) > 4 {
+						after = util.ToRune(line, 4)
+					}
+					if len(line) == 3 || util.IsSpaceRune(after) || util.IsPunctRune(after) {
+						node := gast.NewString(s.Substitutions[Apostrophe])
+						node.SetCode(true)
+						block.Advance(1)
+						return node
+					}
+				}
+				// special cases: 'twas, 'em, 'net
+				if len(line) > 1 && (unicode.IsPunct(before) || unicode.IsSpace(before)) && (line[1] == 't' || line[1] == 'e' || line[1] == 'n' || line[1] == 'l') {
+					node := gast.NewString(s.Substitutions[Apostrophe])
+					node.SetCode(true)
+					block.Advance(1)
+					return node
+				}
+				// Convert normal apostrophes. This is probably more flexible than necessary but
+				// converts any apostrophe in between two alphanumerics.
+				if len(line) > 1 && (unicode.IsDigit(before) || unicode.IsLetter(before)) && (unicode.IsLetter(util.ToRune(line, 1))) {
+					node := gast.NewString(s.Substitutions[Apostrophe])
+					node.SetCode(true)
+					block.Advance(1)
+					return node
+				}
+			}
+			if s.Substitutions[LeftSingleQuote] != nil && d.CanOpen && !d.CanClose {
+				nt := LeftSingleQuote
+				// special cases: Alice's, I'm, Don't, You'd
+				if len(line) > 1 && (line[1] == 's' || line[1] == 'm' || line[1] == 't' || line[1] == 'd') && (len(line) < 3 || util.IsPunct(line[2]) || util.IsSpace(line[2])) {
+					nt = RightSingleQuote
+				}
+				// special cases: I've, I'll, You're
+				if len(line) > 2 && ((line[1] == 'v' && line[2] == 'e') || (line[1] == 'l' && line[2] == 'l') || (line[1] == 'r' && line[2] == 'e')) && (len(line) < 4 || util.IsPunct(line[3]) || util.IsSpace(line[3])) {
+					nt = RightSingleQuote
+				}
+				if nt == LeftSingleQuote {
+					counter.Single++
+				}
+
+				node := gast.NewString(s.Substitutions[nt])
+				node.SetCode(true)
+				block.Advance(1)
+				return node
+			}
+			if s.Substitutions[RightSingleQuote] != nil {
+				// plural possesives and abbreviations: Smiths', doin'
+				if len(line) > 1 && unicode.IsSpace(util.ToRune(line, 0)) || unicode.IsPunct(util.ToRune(line, 0)) && (len(line) > 2 && !unicode.IsDigit(util.ToRune(line, 1))) {
+					node := gast.NewString(s.Substitutions[RightSingleQuote])
+					node.SetCode(true)
+					block.Advance(1)
+					return node
+				}
+			}
+			if s.Substitutions[RightSingleQuote] != nil && counter.Single > 0 {
+				isClose := d.CanClose && !d.CanOpen
+				maybeClose := d.CanClose && d.CanOpen && len(line) > 1 && unicode.IsPunct(util.ToRune(line, 1)) && (len(line) == 2 || (len(line) > 2 && util.IsPunct(line[2]) || util.IsSpace(line[2])))
+				if isClose || maybeClose {
+					node := gast.NewString(s.Substitutions[RightSingleQuote])
+					node.SetCode(true)
+					block.Advance(1)
+					counter.Single--
+					return node
+				}
+			}
+		}
+		if c == '"' {
+			if s.Substitutions[LeftDoubleQuote] != nil && d.CanOpen && !d.CanClose {
+				node := gast.NewString(s.Substitutions[LeftDoubleQuote])
+				node.SetCode(true)
+				block.Advance(1)
+				counter.Double++
+				return node
+			}
+			if s.Substitutions[RightDoubleQuote] != nil && counter.Double > 0 {
+				isClose := d.CanClose && !d.CanOpen
+				maybeClose := d.CanClose && d.CanOpen && len(line) > 1 && (unicode.IsPunct(util.ToRune(line, 1))) && (len(line) == 2 || (len(line) > 2 && util.IsPunct(line[2]) || util.IsSpace(line[2])))
+				if isClose || maybeClose {
+					// special case: "Monitor 21""
+					if len(line) > 1 && line[1] == '"' && unicode.IsDigit(before) {
+						return nil
+					}
+					node := gast.NewString(s.Substitutions[RightDoubleQuote])
+					node.SetCode(true)
+					block.Advance(1)
+					counter.Double--
+					return node
+				}
+			}
+		}
+	}
+	return nil
+}
+
+func (s *typographerParser) CloseBlock(parent gast.Node, pc parser.Context) {
+	getUnclosedCounter(pc).Reset()
+}
+
+type typographer struct {
+	options []TypographerOption
+}
+
+// Typographer is an extension that replaces punctuations with typographic entities.
+var Typographer = &typographer{}
+
+// NewTypographer returns a new Extender that replaces punctuations with typographic entities.
+func NewTypographer(opts ...TypographerOption) goldmark.Extender {
+	return &typographer{
+		options: opts,
+	}
+}
+
+func (e *typographer) Extend(m goldmark.Markdown) {
+	m.Parser().AddOptions(parser.WithInlineParsers(
+		util.Prioritized(NewTypographerParser(e.options...), 9999),
+	))
+}