From 507ff2864dc5fa4ea624382b659de630350a2a5c Mon Sep 17 00:00:00 2001
From: lumir <rpfos@naver.com>
Date: Thu, 8 Oct 2026 20:44:06 +0900
Subject: [PATCH] fix: escaped parentheses in nested labels in
 `no-reversed-media-syntax`

---
 src/rules/no-reversed-media-syntax.js        |   4 +-
 tests/rules/no-reversed-media-syntax.test.js | 131 +++++++++++++++++++
 2 files changed, 133 insertions(+), 2 deletions(-)

diff --git a/src/rules/no-reversed-media-syntax.js b/src/rules/no-reversed-media-syntax.js
index 82e00ec8..141beb74 100644
--- a/src/rules/no-reversed-media-syntax.js
+++ b/src/rules/no-reversed-media-syntax.js
@@ -22,11 +22,11 @@
 
 /**
  * Matches reversed link/image syntax like `(text)[url]`, ignoring escaped characters like `\(text\)[url]`.
- * The nested group is `\([^()]*\)`, not `\([\s\S]*\)`, so that it cannot overlap the
+ * The nested group is `\((?:\\[\s\S]|[^()\\])*\)`, not `\([\s\S]*\)`, so that it cannot overlap the
  * other alternatives. Overlapping alternatives cause catastrophic backtracking.
  */
 const reversedPattern =
-	/(?<=(?<!\\)(?:\\{2})*)\((?<label>(?:\\.|[^()\\]|\([^()]*\))*)\)\[(?<url>(?:\\.|[^\]\\\r\n])*)\](?!\()/gu;
+	/(?<=(?<!\\)(?:\\{2})*)\((?<label>(?:\\.|[^()\\]|\((?:\\[\s\S]|[^()\\])*\))*)\)\[(?<url>(?:\\.|[^\]\\\r\n])*)\](?!\()/gu;
 
 //-----------------------------------------------------------------------------
 // Rule Definition
diff --git a/tests/rules/no-reversed-media-syntax.test.js b/tests/rules/no-reversed-media-syntax.test.js
index a084df3d..4988665e 100644
--- a/tests/rules/no-reversed-media-syntax.test.js
+++ b/tests/rules/no-reversed-media-syntax.test.js
@@ -588,6 +588,137 @@ ruleTester.run("no-reversed-media-syntax", rule, {
 				},
 			],
 		},
+		// Nested parentheses with escaped characters
+		{
+			code: "(a (b \\(c\\)) d)[x]",
+			output: "[a (b \\(c\\)) d](x)",
+			errors: [
+				{
+					messageId: "reversedSyntax",
+					line: 1,
+					column: 1,
+					endLine: 1,
+					endColumn: 19,
+				},
+			],
+		},
+		{
+			code: "!(a (b \\(c\\)) d)[x]",
+			output: "![a (b \\(c\\)) d](x)",
+			errors: [
+				{
+					messageId: "reversedSyntax",
+					line: 1,
+					column: 2,
+					endLine: 1,
+					endColumn: 20,
+				},
+			],
+		},
+		{
+			code: "(a (b\\( c))[x]",
+			output: "[a (b\\( c)](x)",
+			errors: [
+				{
+					messageId: "reversedSyntax",
+					line: 1,
+					column: 1,
+					endLine: 1,
+					endColumn: 15,
+				},
+			],
+		},
+		{
+			code: "!(a (b\\( c))[x]",
+			output: "![a (b\\( c)](x)",
+			errors: [
+				{
+					messageId: "reversedSyntax",
+					line: 1,
+					column: 2,
+					endLine: 1,
+					endColumn: 16,
+				},
+			],
+		},
+		{
+			code: "(a (b\\) c))[x]",
+			output: "[a (b\\) c)](x)",
+			errors: [
+				{
+					messageId: "reversedSyntax",
+					line: 1,
+					column: 1,
+					endLine: 1,
+					endColumn: 15,
+				},
+			],
+		},
+		{
+			code: "!(a (b\\) c))[x]",
+			output: "![a (b\\) c)](x)",
+			errors: [
+				{
+					messageId: "reversedSyntax",
+					line: 1,
+					column: 2,
+					endLine: 1,
+					endColumn: 16,
+				},
+			],
+		},
+		{
+			code: "(a (b\\\\) c)[x]",
+			output: "[a (b\\\\) c](x)",
+			errors: [
+				{
+					messageId: "reversedSyntax",
+					line: 1,
+					column: 1,
+					endLine: 1,
+					endColumn: 15,
+				},
+			],
+		},
+		{
+			code: "!(a (b\\\\) c)[x]",
+			output: "![a (b\\\\) c](x)",
+			errors: [
+				{
+					messageId: "reversedSyntax",
+					line: 1,
+					column: 2,
+					endLine: 1,
+					endColumn: 16,
+				},
+			],
+		},
+		{
+			code: "(a (b\\\nc))[x]",
+			output: "[a (b\\\nc)](x)",
+			errors: [
+				{
+					messageId: "reversedSyntax",
+					line: 1,
+					column: 1,
+					endLine: 2,
+					endColumn: 7,
+				},
+			],
+		},
+		{
+			code: "!(a (b\\\nc))[x]",
+			output: "![a (b\\\nc)](x)",
+			errors: [
+				{
+					messageId: "reversedSyntax",
+					line: 1,
+					column: 2,
+					endLine: 2,
+					endColumn: 7,
+				},
+			],
+		},
 		// Heading
 		{
 			code: "# (ESLint)[https://eslint.org/]",