fix: fix emoji not showing on sidebars (#206)

Author: ycmjason

docs/guide/markdown.md

@@ -112,7 +112,7 @@ meta:
 | col 2 is      | centered      |   $12 |
 | zebra stripes | are neat      |    $1 |
 
-## Emoji
+## Emoji :tada:
 
 **Input**
 

lib/util/index.js

@@ -1,3 +1,8 @@
+const parseEmojis = str => {
+  const emojiData = require('markdown-it-emoji/lib/data/full.json')
+  return str.replace(/:(.+?):/g, (placeholder, key) => emojiData[key] || placeholder)
+}
+
 exports.normalizeHeadTag = tag => {
   if (typeof tag === 'string') {
     tag = [tag]
@@ -30,11 +35,11 @@ exports.inferTitle = function (frontmatter) {
     return 'Home'
   }
   if (frontmatter.data.title) {
-    return frontmatter.data.title
+    return parseEmojis(frontmatter.data.title)
   }
   const match = frontmatter.content.trim().match(/^#+\s+(.*)/)
   if (match) {
-    return match[1]
+    return parseEmojis(match[1])
   }
 }
 
@@ -65,7 +70,7 @@ exports.extractHeaders = (content, include = [], md) => {
   const res = []
   tokens.forEach((t, i) => {
     if (t.type === 'heading_open' && include.includes(t.tag)) {
-      const title = tokens[i + 1].content
+      const title = parseEmojis(tokens[i + 1].content)
       const slug = t.attrs.find(([name]) => name === 'id')[1]
       res.push({
         level: parseInt(t.tag.slice(1), 10),