1 files changed, 37 insertions, 0 deletions
diff --git a/js/src/jit-test/tests/fuses/optimized-getiterator-invalidation.js b/js/src/jit-test/tests/fuses/optimized-getiterator-invalidation.js
new file mode 100644
index 0000000000..6505f8d023
--- /dev/null
+++ b/js/src/jit-test/tests/fuses/optimized-getiterator-invalidation.js
@@ -0,0 +1,37 @@
+
+const ITERS = 1000;
+
+// A function which when warp compiled should use
+// OptimizedGetIterator elision, and rely on invalidation
+function f(x) {
+    let sum = 0;
+    for (let i = 0; i < ITERS; i++) {
+        const [a, b, c] = x
+        sum = a + b + c;
+    }
+    return sum
+}
+
+// Run the function f 1000 times to warp compile it. Use 4 elements here to ensure
+// the return property of the ArrayIteratorPrototype is called.
+let arr = [1, 2, 3, 4];
+for (let i = 0; i < 1000; i++) {
+    f(arr);
+}
+
+// Initialize the globally scoped counter
+let counter = 0;
+const ArrayIteratorPrototype = Object.getPrototypeOf([][Symbol.iterator]());
+
+// Setting the return property should invalidate the warp script here.
+ArrayIteratorPrototype.return = function () {
+    counter++;
+    return { done: true };
+};
+
+
+// Call f one more time
+f(arr);
+
+// Use assertEq to check the value of counter.
+assertEq(counter, ITERS);