diff options
Diffstat (limited to 'vendor/github.com/yuin/goldmark/renderer/html/html.go')
| -rw-r--r-- | vendor/github.com/yuin/goldmark/renderer/html/html.go | 93 |
1 files changed, 83 insertions, 10 deletions
diff --git a/vendor/github.com/yuin/goldmark/renderer/html/html.go b/vendor/github.com/yuin/goldmark/renderer/html/html.go index 350368839..8738c2a1b 100644 --- a/vendor/github.com/yuin/goldmark/renderer/html/html.go +++ b/vendor/github.com/yuin/goldmark/renderer/html/html.go @@ -5,6 +5,7 @@ import ( "bytes" "fmt" "strconv" + "unicode" "unicode/utf8" "github.com/yuin/goldmark/ast" @@ -16,7 +17,7 @@ import ( type Config struct { Writer Writer HardWraps bool - EastAsianLineBreaks bool + EastAsianLineBreaks EastAsianLineBreaks XHTML bool Unsafe bool } @@ -26,7 +27,7 @@ func NewConfig() Config { return Config{ Writer: DefaultWriter, HardWraps: false, - EastAsianLineBreaks: false, + EastAsianLineBreaks: EastAsianLineBreaksNone, XHTML: false, Unsafe: false, } @@ -38,7 +39,7 @@ func (c *Config) SetOption(name renderer.OptionName, value interface{}) { case optHardWraps: c.HardWraps = value.(bool) case optEastAsianLineBreaks: - c.EastAsianLineBreaks = value.(bool) + c.EastAsianLineBreaks = value.(EastAsianLineBreaks) case optXHTML: c.XHTML = value.(bool) case optUnsafe: @@ -103,24 +104,94 @@ func WithHardWraps() interface { // EastAsianLineBreaks is an option name used in WithEastAsianLineBreaks. const optEastAsianLineBreaks renderer.OptionName = "EastAsianLineBreaks" +// A EastAsianLineBreaks is a style of east asian line breaks. +type EastAsianLineBreaks int + +const ( + //EastAsianLineBreaksNone renders line breaks as it is. + EastAsianLineBreaksNone EastAsianLineBreaks = iota + // EastAsianLineBreaksSimple follows east_asian_line_breaks in Pandoc. + EastAsianLineBreaksSimple + // EastAsianLineBreaksCSS3Draft follows CSS text level3 "Segment Break Transformation Rules" with some enhancements. + EastAsianLineBreaksCSS3Draft +) + +func (b EastAsianLineBreaks) softLineBreak(thisLastRune rune, siblingFirstRune rune) bool { + switch b { + case EastAsianLineBreaksNone: + return false + case EastAsianLineBreaksSimple: + return !(util.IsEastAsianWideRune(thisLastRune) && util.IsEastAsianWideRune(siblingFirstRune)) + case EastAsianLineBreaksCSS3Draft: + return eastAsianLineBreaksCSS3DraftSoftLineBreak(thisLastRune, siblingFirstRune) + } + return false +} + +func eastAsianLineBreaksCSS3DraftSoftLineBreak(thisLastRune rune, siblingFirstRune rune) bool { + // Implements CSS text level3 Segment Break Transformation Rules with some enhancements. + // References: + // - https://www.w3.org/TR/2020/WD-css-text-3-20200429/#line-break-transform + // - https://github.com/w3c/csswg-drafts/issues/5086 + + // Rule1: + // If the character immediately before or immediately after the segment break is + // the zero-width space character (U+200B), then the break is removed, leaving behind the zero-width space. + if thisLastRune == '\u200B' || siblingFirstRune == '\u200B' { + return false + } + + // Rule2: + // Otherwise, if the East Asian Width property of both the character before and after the segment break is + // F, W, or H (not A), and neither side is Hangul, then the segment break is removed. + thisLastRuneEastAsianWidth := util.EastAsianWidth(thisLastRune) + siblingFirstRuneEastAsianWidth := util.EastAsianWidth(siblingFirstRune) + if (thisLastRuneEastAsianWidth == "F" || + thisLastRuneEastAsianWidth == "W" || + thisLastRuneEastAsianWidth == "H") && + (siblingFirstRuneEastAsianWidth == "F" || + siblingFirstRuneEastAsianWidth == "W" || + siblingFirstRuneEastAsianWidth == "H") { + return unicode.Is(unicode.Hangul, thisLastRune) || unicode.Is(unicode.Hangul, siblingFirstRune) + } + + // Rule3: + // Otherwise, if either the character before or after the segment break belongs to + // the space-discarding character set and it is a Unicode Punctuation (P*) or U+3000, + // then the segment break is removed. + if util.IsSpaceDiscardingUnicodeRune(thisLastRune) || + unicode.IsPunct(thisLastRune) || + thisLastRune == '\u3000' || + util.IsSpaceDiscardingUnicodeRune(siblingFirstRune) || + unicode.IsPunct(siblingFirstRune) || + siblingFirstRune == '\u3000' { + return false + } + + // Rule4: + // Otherwise, the segment break is converted to a space (U+0020). + return true +} + type withEastAsianLineBreaks struct { + eastAsianLineBreaksStyle EastAsianLineBreaks } func (o *withEastAsianLineBreaks) SetConfig(c *renderer.Config) { - c.Options[optEastAsianLineBreaks] = true + c.Options[optEastAsianLineBreaks] = o.eastAsianLineBreaksStyle } func (o *withEastAsianLineBreaks) SetHTMLOption(c *Config) { - c.EastAsianLineBreaks = true + c.EastAsianLineBreaks = o.eastAsianLineBreaksStyle } // WithEastAsianLineBreaks is a functional option that indicates whether softline breaks // between east asian wide characters should be ignored. -func WithEastAsianLineBreaks() interface { +func WithEastAsianLineBreaks(e EastAsianLineBreaks) interface { renderer.Option Option } { - return &withEastAsianLineBreaks{} + return &withEastAsianLineBreaks{e} } // XHTML is an option name used in WithXHTML. @@ -663,14 +734,13 @@ func (r *Renderer) renderText(w util.BufWriter, source []byte, node ast.Node, en _, _ = w.WriteString("<br>\n") } } else if n.SoftLineBreak() { - if r.EastAsianLineBreaks && len(value) != 0 { + if r.EastAsianLineBreaks != EastAsianLineBreaksNone && len(value) != 0 { sibling := node.NextSibling() if sibling != nil && sibling.Kind() == ast.KindText { if siblingText := sibling.(*ast.Text).Text(source); len(siblingText) != 0 { thisLastRune := util.ToRune(value, len(value)-1) siblingFirstRune, _ := utf8.DecodeRune(siblingText) - if !(util.IsEastAsianWideRune(thisLastRune) && - util.IsEastAsianWideRune(siblingFirstRune)) { + if r.EastAsianLineBreaks.softLineBreak(thisLastRune, siblingFirstRune) { _ = w.WriteByte('\n') } } @@ -938,6 +1008,9 @@ func nodeToHTMLText(n ast.Node, source []byte) []byte { buf.Write(s.Text(source)) } else if !c.HasChildren() { buf.Write(util.EscapeHTML(c.Text(source))) + if t, ok := c.(*ast.Text); ok && t.SoftLineBreak() { + buf.WriteByte('\n') + } } else { buf.Write(nodeToHTMLText(c, source)) } |