1 files changed, 33 insertions, 0 deletions
diff --git a/js/src/jit-test/tests/arguments/iterator-set-and-redefine.js b/js/src/jit-test/tests/arguments/iterator-set-and-redefine.js
new file mode 100644
index 0000000000..bcf182790f
--- /dev/null
+++ b/js/src/jit-test/tests/arguments/iterator-set-and-redefine.js
@@ -0,0 +1,33 @@
+function mapped() {
+    var Iterator = {};
+
+    // First overwrite the iterator.
+    arguments[Symbol.iterator] = Iterator;
+
+    // And then redefine a property attribute.
+    Object.defineProperty(arguments, Symbol.iterator, {
+        writable: false
+    });
+
+    // Make sure redefining an attribute doesn't reset the iterator value.
+    assertEq(arguments[Symbol.iterator], Iterator);
+}
+mapped();
+
+function unmapped() {
+  "use strict";
+
+  var Iterator = {};
+
+  // First overwrite the iterator.
+  arguments[Symbol.iterator] = Iterator;
+
+  // And then redefine a property attribute.
+  Object.defineProperty(arguments, Symbol.iterator, {
+      writable: false
+  });
+
+  // Make sure redefining an attribute doesn't reset the iterator value.
+  assertEq(arguments[Symbol.iterator], Iterator);
+}
+unmapped();