Update emoji regex

modules/emoji/emoji.go

@@ -6,8 +6,10 @@
 package emoji
 
 import (
+	"sort"
 	"strings"
 	"sync"
+	"unicode/utf8"
 )
 
 // Gemoji is a set of emoji data.
@@ -48,6 +50,12 @@ func loadMap() {
 		// process emoji codes and aliases
 		codePairs := make([]string, 0)
 		aliasPairs := make([]string, 0)
+
+		// sort from largest to small so we match combined emoji first
+		sort.Slice(GemojiData, func(i, j int) bool {
+			return len(GemojiData[i].Emoji) > len(GemojiData[j].Emoji)
+		})
+
 		for i, e := range GemojiData {
 			if e.Emoji == "" || len(e.Aliases) == 0 {
 				continue
@@ -72,6 +80,7 @@ func loadMap() {
 		codeReplacer = strings.NewReplacer(codePairs...)
 		aliasReplacer = strings.NewReplacer(aliasPairs...)
 	})
+
 }
 
 // FromCode retrieves the emoji data based on the provided unicode code (ie,
@@ -117,3 +126,21 @@ func ReplaceAliases(s string) string {
 	loadMap()
 	return aliasReplacer.Replace(s)
 }
+
+// FindEmojiSubmatchIndex returns index pair of longest emoji in a string
+func FindEmojiSubmatchIndex(s string) []int {
+	loadMap()
+
+	// if rune and string length are the same then no emoji will be present
+	// similar performance when there is unicode present but almost 200% faster when not
+	if utf8.RuneCountInString(s) == len(s) {
+		return nil
+	}
+	for j := range GemojiData {
+		i := strings.Index(s, GemojiData[j].Emoji)
+		if i != -1 {
+			return []int{i, i + len(GemojiData[j].Emoji)}
+		}
+	}
+	return nil
+}

modules/markup/html.go

@@ -65,10 +65,6 @@ var (
 
 	// EmojiShortCodeRegex find emoji by alias like :smile:
 	EmojiShortCodeRegex = regexp.MustCompile(`\:[\w\+\-]+\:{1}`)
-
-	// find emoji literal: search all emoji hex range as many times as they appear as
-	// some emojis (skin color etc..) are just two or more chained together
-	emojiRegex = regexp.MustCompile(`[\x{1F000}-\x{1FFFF}|\x{2000}-\x{32ff}|\x{fe4e5}-\x{fe4ee}|\x{200D}|\x{FE0F}|\x{e0000}-\x{e007f}]+`)
 )
 
 // CSS class for action keywords (e.g. "closes: #1")
@@ -922,8 +918,7 @@ func emojiShortCodeProcessor(ctx *postProcessCtx, node *html.Node) {
 
 // emoji processor to match emoji and add emoji class
 func emojiProcessor(ctx *postProcessCtx, node *html.Node) {
-	m := emojiRegex.FindStringSubmatchIndex(node.Data)
-
+	m := emoji.FindEmojiSubmatchIndex(node.Data)
 	if m == nil {
 		return
 	}

modules/markup/html_test.go

@@ -263,7 +263,9 @@ func TestRender_emoji(t *testing.T) {
 	test(
 		"Some text with :smile: in the middle",
 		`<p>Some text with <span class="emoji" aria-label="grinning face with smiling eyes">😄</span> in the middle</p>`)
-
+	test(
+		"Some text with 😄😄 2 emoji next to each other",
+		`<p>Some text with <span class="emoji" aria-label="grinning face with smiling eyes">😄</span><span class="emoji" aria-label="grinning face with smiling eyes">😄</span> 2 emoji next to each other</p>`)
 	// should match nothing
 	test(
 		"2001:0db8:85a3:0000:0000:8a2e:0370:7334",