Thenkas for the translation. I just updated the description to make it clearer that the second argument of the getSerie function is optional and should default to 0.

The fact that the argument is optional was only mentioned in the docbloc of the getSerie() function, now it is also in the description.

You are right, it was only mentioned in the docbloc of the getSerie() function, now it is also in the description.

I don't understand: the code you pasted here is a valid solution (at least now). What was the issue ?

I agree it's a little verbose... I was playing with different node modules about code quality and tried to reach a nice score, so I copy / pasted that skeleton and the adapted my tests. :D

Are you suggesting that I remove the test cases for the object and the functions or more than that ?
If it's also about the numerical test cases being the ones in the description, it's because I hate typing test cases that are only in the description.

It seems that Number.parseInt() gives the error on the CodeWars website. If you simply use parseInt, it will work.

Thank you very much for your detailed comments.

I simplified this kata by removing all error checking, since it is a simple kata and you're right that error checking took away all the fun altogether.

I will have a look at the libraries you mention, and I'll search for kata that deals with errors or maybe make one in the future.

In your kata description, you write that motto("Tyrell") should return "growing strong" (lowercased) while the correct answer should be "Growing Strong".

Nice fundamental kata. In my opinion, the following edge test cases also make sense:

Test.expect(![].all(isGreaterThanZero), 'An empty array has not all elements greater than zero');
Test.expect(![].any(isGreaterThanZero), 'An empty array has not any element greater than zero');
Test.expect([].none(isGreaterThanZero), 'An empty array has none element greater than zero');

Test.expect(![].all(isLessThanZero), 'An empty array has not all elements lower or equal than zero');
Test.expect(![].any(isLessThanZero), 'An empty array has not any element lower or equal than zero');
Test.expect([].none(isLessThanZero), 'An empty array has none element greater or equal than zero');