From 6bb264663577e618c4ce6b1405cec62722c8d8d0 Mon Sep 17 00:00:00 2001
From: Taufik Nurrohman <hi@taufik-nurrohman.com>
Date: Mon, 12 Feb 2024 00:14:00 +0700
Subject: [PATCH] fix(auto-render): strict dollar delimiter

The dollar delimiter, especially the non-display version, is disabled by default
because it often causes errors in determining the boundary when there are at
least two numbers followed by the `$` symbol present in one paragraph.

This change makes it possible to make the delimiter stricter in determining
the math boundary, by checking what characters come before the opening delimiter
and what characters come after the closing delimiter.

Tests are available as follows:

~~~ html
<ul>
  <li>$E=mc^2$</li>
  <li>$E=mc^2$asdf</li>
  <li>asdf$E=mc^2$</li>
  <li>asdf$E=mc^2$asdf</li>
  <li>$E=mc^2$ asdf</li>
  <li>asdf $E=mc^2$</li>
  <li>asdf $E=mc^2$ asdf</li>
  <li>($E=mc^2$)asdf</li>
  <li>asdf($E=mc^2$)</li>
  <li>asdf($E=mc^2$)asdf</li>
  <li>asdf asdf 20$ asdf 30$ asdf asdf asdf</li>
  <li>asdf asdf $20 asdf $30 asdf asdf asdf</li>
  <li>asdf asdf $20 asdf 30$ asdf asdf asdf</li>
  <li>asdf asdf 20 $ asdf 30 $ asdf asdf asdf</li>
  <li>asdf asdf $ 20 asdf $ 30 asdf asdf asdf</li>
  <li>asdf asdf $ 20 asdf 30 $ asdf asdf asdf</li>
</ul>

<ul>
  <li>$$E=mc^2$$</li>
  <li>$$E=mc^2$$asdf</li>
  <li>asdf$$E=mc^2$$</li>
  <li>asdf$$E=mc^2$$asdf</li>
  <li>$$E=mc^2$$ asdf</li>
  <li>asdf $$E=mc^2$$</li>
  <li>asdf $$E=mc^2$$ asdf</li>
  <li>($$E=mc^2$$)asdf</li>
  <li>asdf($$E=mc^2$$)</li>
  <li>asdf($$E=mc^2$$)asdf</li>
  <li>asdf asdf 20$$ asdf 30$$ asdf asdf asdf</li>
  <li>asdf asdf $$20 asdf $$30 asdf asdf asdf</li>
  <li>asdf asdf $$20 asdf 30$$ asdf asdf asdf</li>
  <li>asdf asdf 20 $$ asdf 30 $$ asdf asdf asdf</li>
  <li>asdf asdf $$ 20 asdf $$ 30 asdf asdf asdf</li>
  <li>asdf asdf $$ 20 asdf 30 $$ asdf asdf asdf</li>
</ul>

<ul>
  <li>asdf +10$ asdf -10$ asdf</li>
  <li>asdf +10 $ asdf -10 $ asdf</li>
  <li>asdf $+10 asdf $-10 asdf</li>
  <li>asdf $ +10 asdf $ -10 asdf</li>
</ul>

<ul>
  <li>asdf +10.5$ asdf -10.5$ asdf</li>
  <li>asdf +10.5 $ asdf -10.5 $ asdf</li>
  <li>asdf $+10.5 asdf $-10.5 asdf</li>
  <li>asdf $ +10.5 asdf $ -10.5 asdf</li>
</ul>

<ul>
  <li>asdf +10,5$ asdf -10,5$ asdf</li>
  <li>asdf +10,5 $ asdf -10,5 $ asdf</li>
  <li>asdf $+10,5 asdf $-10,5 asdf</li>
  <li>asdf $ +10,5 asdf $ -10,5 asdf</li>
</ul>

<ul>
  <li>asdf +10,000,000.5$ asdf -10,000,000.5$ asdf</li>
  <li>asdf +10,000,000.5 $ asdf -10,000,000.5 $ asdf</li>
  <li>asdf $+10,000,000.5 asdf $-10,000,000.5 asdf</li>
  <li>asdf $ +10,000,000.5 asdf $ -10,000,000.5 asdf</li>
</ul>

<ul>
  <li>asdf +10.000.000,5$ asdf -10.000.000,5$ asdf</li>
  <li>asdf +10.000.000,5 $ asdf -10.000.000,5 $ asdf</li>
  <li>asdf $+10.000.000,5 asdf $-10.000.000,5 asdf</li>
  <li>asdf $ +10.000.000,5 asdf $ -10.000.000,5 asdf</li>
</ul>

<ul>
  <li>asdf1234$E=mc^2$</li>
  <li>asdf1234$E=mc^2$1234asdf</li>
  <li>$E=mc^2$1234asdf</li>
  <li>asdf1234 $E=mc^2$</li>
  <li>asdf1234 $E=mc^2$ 1234asdf</li>
  <li>$E=mc^2$ 1234asdf</li>
</ul>
~~~
---
 contrib/auto-render/splitAtDelimiters.js | 27 ++++++++++++++++++------
 1 file changed, 20 insertions(+), 7 deletions(-)

diff --git a/contrib/auto-render/splitAtDelimiters.js b/contrib/auto-render/splitAtDelimiters.js
index 21b59030a5..c2679eb820 100644
--- a/contrib/auto-render/splitAtDelimiters.js
+++ b/contrib/auto-render/splitAtDelimiters.js
@@ -63,13 +63,26 @@ const splitAtDelimiters = function(text, delimiters) {
         const math = amsRegex.test(rawData)
             ? rawData
             : text.slice(delimiters[i].left.length, index);
-        data.push({
-            type: "math",
-            data: math,
-            rawData,
-            display: delimiters[i].display,
-        });
+        let previousData = data.slice(-1).pop(),
+            // Treat current data as plain text if previous data ends with any words or any numbers with optional space after them
+            currentData = previousData && /(\w|\b[+-]?\d+([,.]\d+)*\s*)$/.test(previousData.data) && rawData[0] === '$' ? {
+                type: "text",
+                data: rawData,
+            } : {
+                type: "math",
+                data: math,
+                rawData,
+                display: delimiters[i].display,
+            };
         text = text.slice(index + delimiters[i].right.length);
+        // Treat current data as plain text if next data starts with any words or any numbers with optional space after them
+        if (currentData.type === "math" && /^(\w|\s*[+-]?\d+([,.]\d+)*\b)/.test(text) && currentData.rawData[0] === '$') {
+            currentData.type = "text";
+            currentData.data = currentData.rawData;
+            delete currentData.display;
+            delete currentData.rawData;
+        }
+        data.push(currentData);
     }
 
     if (text !== "") {
@@ -82,4 +95,4 @@ const splitAtDelimiters = function(text, delimiters) {
     return data;
 };
 
-export default splitAtDelimiters;
+export default splitAtDelimiters;
\ No newline at end of file