there's an extra " in one of the testcases:
/home/codewarrior/test.js:29
Test.assertEquals(BFxor(1, 1), 0");
^^^

I feel this line in the Haskell test: "forAll (filter (\k -> k notElem "xXoO") fmap arbitrary) $ \str ->" gives a bit too much of a hint, then again, might be fair for a 7kyu kata.