Was copied from Ruby translation which doesn't have random tests, just going to unpublish

Done

Fixed it, but this is a very common problem

Still needs random tests

Forked

Forked

Fixed both

Assume we are working on the binary number 1101001.

The first bit is 1, and since (0 << 1) + bit is 0 + bit which is just the bit, the result is set to just this bit.

The second bit is also 1, so we left shift the result by 1, making the result 10 in binary. Since the final bit is 0 and bits are numbers between 0 and 1, adding a bit here would be the same as setting the last bit to the new bit (same with OR operator). Adding the bit to the result, we get 11.

Third bit is 0, left shift result by 1, get 110, add 0, get 110.

Fourth bit is 1, left shift result by 1, get 1100, add 1, get 1101.

Hopefully this makes it more clear.

Done, see https://www.codewars.com/kumite/5e9c1678ae2b04001df4f5e5?sel=5fc768eb0ad5b1001302d54f

Yes, the kata specifically mentions 0 < str length < 1000

Yes, seems good, the sitewide fixes means every kata is absolved.

Fixed in fork

There was a merge conflict, forked with the fix

Yes, thank you, that works, it was stupid of me to not think of that. I've changed the kata tests and the sample tests to that, the sample tests because they add clarity.

I've changed it, is it fine? I would have liked to use && instead of || here but only || evaluates both sides (since it returns nil). I've also changed it from should eq true to should be_true for simplicity's sake, but I can revert if eq true sounds more natural.