diff -r 000000000000 -r 6474c204b198 js/src/jit-test/tests/collections/Set-iterator-order.js
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/js/src/jit-test/tests/collections/Set-iterator-order.js	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,14 @@
+// Set iterators produces entries in the order they were inserted.
+
+var set = Set();
+var i;
+for (i = 7; i !== 1; i = i * 7 % 1117)
+    set.add(i);
+assertEq(set.size, 557);
+
+i = 7;
+for (var v of set) {
+    assertEq(v, i);
+    i = i * 7 % 1117;
+}
+assertEq(i, 1);