diff --git a/‎lib/rules/prefer-template.js‎
Lines changed: 1 addition & 1 deletion b/‎lib/rules/prefer-template.js‎
Lines changed: 1 addition & 1 deletion
diff --git a/‎tests/lib/rules/prefer-template.js‎
Lines changed: 11 additions & 0 deletions b/‎tests/lib/rules/prefer-template.js‎
Lines changed: 11 additions & 0 deletions
@@ -204,7 +204,7 @@ module.exports = {
 				 */
 				return `\`${currentNode.raw
 					.slice(1, -1)
-					.replace(/\\*(\$\{|`)/gu, matched => {
+					.replace(/(?<!\\)\\*(\$\{|`)/gu, matched => {
 						if (matched.lastIndexOf("\\") % 2) {
 							return `\\${matched}`;
 						}
 
@@ -408,5 +408,16 @@ ruleTester.run("prefer-template", rule, {
 			output: "`Hello ` + `'world' ${  test}`",
 			errors,
 		},
+
+		/*
+		 * Performance test for handling escape characters.
+		 * A quadratic-time regex would need several minutes,
+		 * thus exceeding the timeout for tests.
+		 */
+		{
+			code: `"${"\\".repeat(1_000_000)}" + test`,
+			output: `\`${"\\".repeat(1_000_000)}\${  test}\``,
+			errors,
+		},
 	],
 });
Original file line number	Diff line number	Diff line change
`@@ -204,7 +204,7 @@ module.exports = {`
`204`	`204`	`*/`
`205`	`205`	return `\`${currentNode.raw
`206`	`206`	`.slice(1, -1)`
`207`		- .replace(/\\*(\$\{\|`)/gu, matched => {
	`207`	+ .replace(/(?<!\\)\\*(\$\{\|`)/gu, matched => {
`208`	`208`	`if (matched.lastIndexOf("\\") % 2) {`
`209`	`209`	return `\\${matched}`;
`210`	`210`	`}`