Thanks for responding so quickly. Honestly, I think the test case shouldn't deal with case insensitivity, rather the solutinons we code should, however I appreciate you addressing my concern.

By the way, I did really enjoy the challenge. Thanks!

You're solution is almost right, but for the first Light test it failed because it generates the given object :

> groupAnagrams(["rat", "tar", "star"])
[ [ 'rat', 'tar' ], 
  [ 'star' ], 
  undefined ]

The undefined should not be part of the output for the test to succeed.

Cheers

I've fixed the assertSimilarUnsorted to compare lowercase string versions. Thanks for noticing it !

I feel like the tests cases have invalid failures since it's case senistive. As a result "Rats" is not an anagram of "rats" which it most certainly is.