diff -r 000000000000 -r 6474c204b198 js/src/jit-test/tests/arrow-functions/block-1.js
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/js/src/jit-test/tests/arrow-functions/block-1.js	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,6 @@
+// Braces after => indicate a block body as opposed to an expression body.
+
+var f = () => {};
+assertEq(f(), undefined);
+var g = () => ({});
+assertEq(typeof g(), 'object');