From 3f2088ad1c4b1180c68cfe36e798741ef2456d4b Mon Sep 17 00:00:00 2001
From: Shumpei Shiina <s417.lama@gmail.com>
Date: Tue, 4 Jan 2022 00:23:49 +0900
Subject: [PATCH] Support GitLab-style math expressions ($`...`$ and ```math
 ... ```)

---
 README.md             | 4 ++--
 background/mathjax.js | 1 +
 content/index.js      | 9 +++++++++
 3 files changed, 12 insertions(+), 2 deletions(-)

diff --git a/README.md b/README.md
index 6652732..d4eb335 100644
--- a/README.md
+++ b/README.md
@@ -118,8 +118,8 @@ When enabled the extension will make a GET request every second to:
 
 The following `mathjax` delimiters are supported:
 
-- inline math: `\(math\)` and `$math$`
-- display math: `\[math\]` and `$$math$$`
+- inline math: `\(math\)`, `$math$`, and ``$`math`$``
+- display math: `\[math\]`, `$$math$$`, and math code blocks (```` ```math ````)
 
 The following rules apply to your content when `mathjax` is enabled:
 
diff --git a/background/mathjax.js b/background/mathjax.js
index 4bd9214..3d51cbe 100644
--- a/background/mathjax.js
+++ b/background/mathjax.js
@@ -7,6 +7,7 @@ md.mathjax = () => {
     /\\\[[^`]*?\\\]/,
     /\\begin\{.*?\}[^`]*?\\end\{.*?\}/,
     /\$[^`\n]*?\$/,
+    /\$`[^`\n]*?`\$/,
   ]
   .map((regex) => `(?:${regex.source})`).join('|'), 'gi')
 
diff --git a/content/index.js b/content/index.js
index 34875fd..41140d8 100644
--- a/content/index.js
+++ b/content/index.js
@@ -104,6 +104,14 @@ function mount () {
             dom.push(m('script', {
               src: 'https://cdnjs.cloudflare.com/ajax/libs/mathjax/2.7.9/MathJax.js'
             }))
+            dom.push(m('script', {type: 'text/javascript'}, `
+              ;(() => {
+                var mathblocks = document.querySelectorAll('code.language-math')
+                mathblocks.forEach(mathblock => {
+                  mathblock.parentNode.replaceWith("$$" + mathblock.textContent + "$$")
+                })
+              })()
+            `))
           }
           if (state.content.mermaid) {
             dom.push(m('script', {
@@ -336,6 +344,7 @@ var mathjax = `
       inlineMath: [
         ['$', '$'],
         ['\\\\(', '\\\\)'],
+        ['$\`', '\`$'],
       ],
       displayMath: [
         ['$$', '$$'],