fix: no-missing-label-refs rule does not respect escaping (#348)

* fix: `no-missing-label-refs` rule does not respect escaping

* wip: add an invalid test

* wip: handle edge cases

Author: lumirlumir

src/rules/no-missing-label-refs.js

@@ -40,7 +40,8 @@ function findMissingReferences(node, nodeText) {
 	 * `left` is the content between the first brackets. It can be empty.
 	 * `right` is the content between the second brackets. It can be empty, and it can be undefined.
 	 */
-	const labelPattern = /\[(?<left>[^\]]*)\](?:\[(?<right>[^\]]*)\])?/dgu;
+	const labelPattern =
+		/(?<!\\)\[(?<left>(?:\\.|[^\]])*)(?<!\\)\](?<!\\)(?:\[(?<right>(?:\\.|[^\]])*)(?<!\\)\])?/dgu;
 
 	let match;
 

tests/rules/no-missing-label-refs.test.js

@@ -44,6 +44,17 @@ ruleTester.run("no-missing-label-refs", rule, {
 		"foo][bar]\n\n[bar]: http://bar.com",
 		"foo][bar][baz]\n\n[baz]: http://baz.com",
 		"[][foo]\n\n[foo]: http://foo.com",
+		"\\[\\]",
+		"[\\]",
+		"\\[]",
+		"\\[escaped\\]",
+		"\\[escaped]",
+		"[escaped\\]",
+		"\\[escaped\\]\\[escaped\\]",
+		"\\[escaped\\]\\[escaped]",
+		"[escaped\\]\\[escaped\\]",
+		"\\[escaped]\\[escaped]",
+		"[escaped\\][escaped\\]",
 	],
 	invalid: [
 		{
@@ -331,5 +342,44 @@ ruleTester.run("no-missing-label-refs", rule, {
 				},
 			],
 		},
+		{
+			code: "\\[[foo]\\]",
+			errors: [
+				{
+					messageId: "notFound",
+					data: { label: "foo" },
+					line: 1,
+					column: 4,
+					endLine: 1,
+					endColumn: 7,
+				},
+			],
+		},
+		{
+			code: "[\\[foo\\]]",
+			errors: [
+				{
+					messageId: "notFound",
+					data: { label: "\\[foo\\]" },
+					line: 1,
+					column: 2,
+					endLine: 1,
+					endColumn: 9,
+				},
+			],
+		},
+		{
+			code: "[\\[\\[foo\\]\\]]",
+			errors: [
+				{
+					messageId: "notFound",
+					data: { label: "\\[\\[foo\\]\\]" },
+					line: 1,
+					column: 2,
+					endLine: 1,
+					endColumn: 13,
+				},
+			],
+		},
 	],
 });