Fix circular selector detection in t.like()

novemberborn · novemberborn · commit 2c671061aa8a · 2023-06-16T17:48:10.000+02:00
The previous implementation tracked each object, even if not circular. Update to use a stack. Fixes #3205.
diff --git a/lib/like-selector.js b/lib/like-selector.js
@@ -16,13 +16,7 @@ export function isLikeSelector(selector) {
 
 export const CIRCULAR_SELECTOR = new Error('Encountered a circular selector');
 
-export function selectComparable(actual, selector, circular = new Set()) {
-	if (circular.has(selector)) {
-		throw CIRCULAR_SELECTOR;
-	}
-
-	circular.add(selector);
-
+export function selectComparable(actual, selector, circular = [selector]) {
 	if (isPrimitive(actual)) {
 		return actual;
 	}
@@ -31,9 +25,17 @@ export function selectComparable(actual, selector, circular = new Set()) {
 	const enumerableKeys = Reflect.ownKeys(selector).filter(key => Reflect.getOwnPropertyDescriptor(selector, key).enumerable);
 	for (const key of enumerableKeys) {
 		const subselector = Reflect.get(selector, key);
-		comparable[key] = isLikeSelector(subselector)
-			? selectComparable(Reflect.get(actual, key), subselector, circular)
-			: Reflect.get(actual, key);
+		if (isLikeSelector(subselector)) {
+			if (circular.includes(subselector)) {
+				throw CIRCULAR_SELECTOR;
+			}
+
+			circular.push(subselector);
+			comparable[key] = selectComparable(Reflect.get(actual, key), subselector, circular);
+			circular.pop();
+		} else {
+			comparable[key] = Reflect.get(actual, key);
+		}
 	}
 
 	return comparable;
diff --git a/test-tap/assert.js b/test-tap/assert.js
@@ -741,6 +741,11 @@ test('.like()', t => {
 		return assertions.like(specimen, selector);
 	});
 
+	passes(t, () => {
+		const array = ['c1', 'c2'];
+		return assertions.like({a: 'a', b: 'b', c: ['c1', 'c2'], d: ['c1', 'c2']}, {b: 'b', d: array, c: array});
+	});
+
 	failsWith(t, () => {
 		const likePattern = {
 			a: 'a',
