Don't use array.push(...spread) with unknown input

[DingoEatingFuzz]

Using array.push(...spread) is quite nice and convenient, but unfortunately providing too many arguments to a function call can cause a stack overflow, which happened to us.

Minimum reproduction Twiddle

Also unfortunately, using Array#concat changes the API, since it returns a new array rather than modifying the original. Also also unfortunately, simply iterating over an array and pushing one-by-one is significantly slower than using spread or concat.

Performance tests JSBin

This implementation is a hybrid approach of looping and spreading that remains stack safe.

If we can guarantee that using concat is safe, that'd be an even better implementation since it's both part of the standard lib and also faster.

[runspired]

Using concat here should be safe

[snewcomer]

@DingoEatingFuzz Is this something you would like to push across the line with concat? Happy to help if you don't have time as well.

[DingoEatingFuzz]

Hey @snewcomer, I'm working on updating the branch right now. Should be done today 🙂

[snewcomer]

I think this is ok! tests in the console seem to verify!

const source = new Array(130000);
const input = [];
input(...source);