1 files changed, 34 insertions, 0 deletions
diff --git a/js/src/tests/test262/built-ins/Array/prototype/with/length-increased-while-iterating.js b/js/src/tests/test262/built-ins/Array/prototype/with/length-increased-while-iterating.js
new file mode 100644
index 0000000000..01e3147e51
--- /dev/null
+++ b/js/src/tests/test262/built-ins/Array/prototype/with/length-increased-while-iterating.js
@@ -0,0 +1,34 @@
+// Copyright (C) 2021 Igalia, S.L. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+
+/*---
+esid: sec-array.prototype.with
+description: >
+  Array.prototype.with caches the length getting the array elements.
+info: |
+  Array.prototype.with ( index, value )
+
+  ...
+  2. Let len be ? LengthOfArrayLike(O).
+  ...
+  5. Repeat, while k < len
+    a. Let Pk be ! ToString(𝔽(k)).
+    b. If k is actualIndex, let fromValue be value.
+    c. Else, let fromValue be ? Get(O, Pk).
+    d. Perform ? CreateDataPropertyOrThrow(A, Pk, fromValue).
+    e. Set k to k + 1.
+features: [change-array-by-copy]
+includes: [compareArray.js]
+---*/
+
+var arr = [0, 1, 2];
+Object.defineProperty(arr, "0", {
+  get() {
+    arr.push(4);
+    return 0;
+  }
+});
+
+assert.compareArray(arr.with(1, 4), [0, 4, 2]);
+
+reportCompare(0, 0);