From 41ccfce3e9c04f217c29aff7bfd7c3d434eb9149 Mon Sep 17 00:00:00 2001
From: Yunus Ozen <94426948+ozenyunus35@users.noreply.github.com>
Date: Wed, 14 Oct 2026 22:11:13 +0300
Subject: [PATCH] fix(markup): parse \(...\) inline math next to letters and
 digits (#39773)

Fixes https://github.com/go-gitea/gitea/issues/39770

`\(x^2\)is` and `\(x^2\)123` rendered as plain text because `\(...\)`
went through the same check on surrounding characters as `$...$`. That
check is there to skip things like `US$1`, which can't happen with
explicit `\(` `\)` delimiters, so it's now skipped for them, the same as
for "$`...`$". `$x$a` still isn't parsed.
---
 modules/markup/markdown/markdown_math_test.go | 4 ++++
 modules/markup/markdown/math/inline_parser.go | 1 +
 2 files changed, 5 insertions(+)

diff --git a/modules/markup/markdown/markdown_math_test.go b/modules/markup/markdown/markdown_math_test.go
index c96ab208db1..f2a64da9dfc 100644
--- a/modules/markup/markdown/markdown_math_test.go
+++ b/modules/markup/markdown/markdown_math_test.go
@@ -42,6 +42,10 @@ func TestMathRender(t *testing.T) {
 			`\(a\) \(b\)`,
 			`<p><code class="language-math">a</code> <code class="language-math">b</code></p>` + nl,
 		},
+		{
+			`\(x^2\)is \(x^2\)123 a\(b\)c`,
+			`<p><code class="language-math">x^2</code>is <code class="language-math">x^2</code>123 a<code class="language-math">b</code>c</p>` + nl,
+		},
 		{
 			`$a$.`,
 			`<p><code class="language-math">a</code>.</p>` + nl,
diff --git a/modules/markup/markdown/math/inline_parser.go b/modules/markup/markdown/math/inline_parser.go
index 111e4038349..fe56d29137d 100644
--- a/modules/markup/markdown/math/inline_parser.go
+++ b/modules/markup/markdown/math/inline_parser.go
@@ -91,6 +91,7 @@ func (parser *inlineParser) Parse(parent ast.Node, block text.Reader, pc parser.
 	} else {
 		startMarkLen = 2
 		stopMark = parser.endBytesParentheses
+		checkSurrounding = false // explicit delimiters like "$`...`$", adjacent text is unambiguous
 	}
 
 	if line[0] == '$' && !parser.enableInlineDollar && (len(line) == 1 || line[1] != '`') {