diff -r 000000000000 -r 6474c204b198 js/src/jit-test/tests/arrow-functions/precedence-5.js
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/js/src/jit-test/tests/arrow-functions/precedence-5.js	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,3 @@
+// map(x => x, 32) is two arguments, not one
+
+assertEq("" + [1, 2, 3, 4].map(x => x, 32), "1,2,3,4");