feat: suppport auto generating toc content for the '[TOC]' placeholder, related #3022

tests/fixtures/markdowns.js

@@ -109,6 +109,14 @@ const footnote = `
 hello-world: https://github.com/BoostIO/Boostnote/
 `
 
+const tocPlaceholder = `
+[TOC]
+# H1
+## H2
+### H3
+###$ H4
+`
+
 export default {
   basic,
   codeblock,
@@ -121,5 +129,6 @@ export default {
   supTexts,
   deflists,
   shortcuts,
-  footnote
+  footnote,
+  tocPlaceholder
 }

tests/lib/markdown-test.js

@@ -73,3 +73,8 @@ test('Markdown.render() should render footnote correctly', t => {
   const rendered = md.render(markdownFixtures.footnote)
   t.snapshot(rendered)
 })
+
+test('Markdown.render() should renders [TOC] placholder correctly', t => {
+  const rendered = md.render(markdownFixtures.tocPlaceholder)
+  t.snapshot(rendered)
+})

tests/lib/snapshots/markdown-test.js.md

@@ -48,6 +48,28 @@ Generated by [AVA](https://ava.li).
     `<span class="katex-display"><span class="katex"><span class="katex-mathml"><math><semantics><mrow><mi>c</mi><mo>=</mo><mi>p</mi><mi>m</mi><mi>s</mi><mi>q</mi><mi>r</mi><mi>t</mi><mrow><msup><mi>a</mi><mn>2</mn></msup><mo>+</mo><msup><mi>b</mi><mn>2</mn></msup></mrow></mrow><annotation encoding="application/x-tex">c = pmsqrt{a^2 + b^2}</annotation></semantics></math></span><span class="katex-html" aria-hidden="true"><span class="base"><span class="strut" style="height:0.43056em;vertical-align:0em;"></span><span class="mord mathdefault">c</span><span class="mspace" style="margin-right:0.2777777777777778em;"></span><span class="mrel">=</span><span class="mspace" style="margin-right:0.2777777777777778em;"></span></span><span class="base"><span class="strut" style="height:1.0585479999999998em;vertical-align:-0.19444em;"></span><span class="mord mathdefault">p</span><span class="mord mathdefault">m</span><span class="mord mathdefault">s</span><span class="mord mathdefault" style="margin-right:0.03588em;">q</span><span class="mord mathdefault" style="margin-right:0.02778em;">r</span><span class="mord mathdefault">t</span><span class="mord"><span class="mord"><span class="mord mathdefault">a</span><span class="msupsub"><span class="vlist-t"><span class="vlist-r"><span class="vlist" style="height:0.8641079999999999em;"><span style="top:-3.113em;margin-right:0.05em;"><span class="pstrut" style="height:2.7em;"></span><span class="sizing reset-size6 size3 mtight"><span class="mord mtight">2</span></span></span></span></span></span></span></span><span class="mspace" style="margin-right:0.2222222222222222em;"></span><span class="mbin">+</span><span class="mspace" style="margin-right:0.2222222222222222em;"></span><span class="mord"><span class="mord mathdefault">b</span><span class="msupsub"><span class="vlist-t"><span class="vlist-r"><span class="vlist" style="height:0.8641079999999999em;"><span style="top:-3.113em;margin-right:0.05em;"><span class="pstrut" style="height:2.7em;"></span><span class="sizing reset-size6 size3 mtight"><span class="mord mtight">2</span></span></span></span></span></span></span></span></span></span></span></span></span>␊
     `
 
+## Markdown.render() should renders [TOC] placholder correctly
+
+> Snapshot 1
+
+    `<p data-line="1"><ul class="markdownIt-TOC">␊
+    <li><a href="#h1">H1</a>␊
+    <ul>␊
+    <li><a href="#h2">H2</a>␊
+    <ul>␊
+    <li><a href="#h3">H3</a></li>␊
+    </ul>␊
+    </li>␊
+    </ul>␊
+    </li>␊
+    </ul>␊
+    </p>␊
+    <h1 id="H1" data-line="2">H1</h1>␊
+    <h2 id="H2" data-line="3">H2</h2>␊
+    <h3 id="H3" data-line="4">H3</h3>␊
+    <p data-line="5">###$ H4</p>␊
+    `
+
 ## Markdown.render() should renders abbrevations correctly
 
 > Snapshot 1