Great example of how native JS code and frameworks like jQuery are interrelated.

well, most of thesedid not account for that case, but at least there are not so many of them relatively (about ~30 still stayed)

lots of undeserving solutions invalidated

hotfix applied, now the tests should test the mutating as well.

In double and multiply

This should change the values of the source array;

The mutating is not tested, just the return value.

reraised as issue.

added more chaining methods; your solution should not pass on the additional tests right now.

that one is weird, because the author's tests were identical except for these functions. Well, I've rewrote them to comply with Node v18 and now they all use assert.deepEqual both on submission and sample tests, so the issue should've been resolved by now.

done

fixed

An attempt to enforce that has been made in the latest fork by me; at least your solution should not pass the tests about checking the methods.

The chaining methods are not tested completely. See this solution

I bloody love this Kata!

this issue is not reproducible - the kata is currently solvable. this is likely due to changes in the Node.JS environment / code runner setup for JS on Codewars (perhaps because Babel is no longer used - though I cannot replicate the issue even with the old Node v8.1.3/Babel version. But it would still be solvable even without that specific feature.