Your issue ;-)

I don't know if "string rotation" is a common concept but I haven't heard of it. Due to lack of explanation the solution involves more guesswork then it should in my opnion.

Agree with all the above. For now there is too much guesswork involved in solving this kata.

Hard to tell only based on Passed/Failed report.
The tests and final submission often use different tests, with the final submission ones being more extensive.
So you most likely have a problem with you algorithm that is not apparent in the simpler tests.
(Just noticed your comment is from 8 months ago, but I'm posting the reply anyway lol)

Oh yeah, if it's "assertNotEquals" hehe.
Yes, seems ok to me now.

Looks good to me!

Actually, it should be
Test.assertNotEquals(longestPalindrome("zyabyz"), 6, "Are you sure that is a palindrome?")

Please check again. Thanks much!

I fixed that test case. Please check now.

In "Your Test Cases":
Test.assertEquals(longestPalindrome("zyabyz", 0, "Are you sure that is a palindrome?")
should be:
Test.assertEquals(longestPalindrome("zyabyz"), 1, "Are you sure that is a palindrome?")
There is a parenthesis missing and the expected value is wrong, should be 1 rather then 0;

More tests including some random ones for the final submission might be good.

Thanks! Yes, I had a while loop with a semicolon after the condition lol.
For some reason it wasn't a problem when running tests...

You might have an infinite loop somewhere? None of the test cases are particularly computationally intensive.

I am getting "Process was terminated. It took longer than 6000ms to complete"...
My solution which worked for the simple testcases relies on arrays. Is that the problem?

Very clever! :)

Thanks. Yes, makes perfect sense. I should have thought a bit harder :)

Think of the plugboard with its sockets, wires and plugs in a physical sense.

Does it make sense to have more than one plug connected to a single socket on the plugboard?