fix: array.lastIndexOf without second argument

[paoloricciuti]

Svelte 5 rewrite

Close #11756

I think lastIndexOf is using arguments internally so passing undefined is different from not passing it (you can test that in the console)

I've resorted to pass item.length but another possibly more correct solution could be to do

const args = [this, item];
if(from_index){
    args.push(from_index);
}

and then spread those as arguments but it seemed unnecessary.

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[dummdidumm]

Strange how this only applies to lastIndexOf - thanks for the fix!

[paoloricciuti]

Strange how this only applies to lastIndexOf - thanks for the fix!

I think it applies to the rest too...but lastIndexOf has a non 0 default value and undefined get's converted to Number. For indexOf and includes is not an issue since NaN is still treated as 0 while it's an issue for lastIndexOf