diff -r 000000000000 -r 6474c204b198 js/src/tests/ecma_6/Comprehensions/syntax.js
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/js/src/tests/ecma_6/Comprehensions/syntax.js	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,6 @@
+// "let" is not allowed as an identifier.
+
+assertThrowsInstanceOf(function () { eval('[for (let of y) foo]') }, SyntaxError);
+assertThrowsInstanceOf(function () { eval('(for (let of y) foo)') }, SyntaxError);
+
+reportCompare(null, null, "test");