All similar changes make sense, but I'm not sure the rest does: passing an int will just work in Symfony 5, thanks to thestring type. Ppl that use strict mode won't have a smooth upgrade path that's true, but are we going to ask everyone to make their code "strict" while only some actually need it? Not sure...

I agree that we should rely on auto casting internally. No need to forbid integers passed from users. See#32066
I don't see what these changes try to accomplish.

@Tobion , these changes are for the ones calling$form->add(1) from classes with strict types enabled. Once we addstring type in5.0, they will have an error.

But now I see the point of@nicolas-grekas better (we already discussed that earlier): if a user doesdeclare(strict_types=1), it's her responsibility to check that she passes correct arguments, because Symfony is not strict about types.

Strict types is a bad idea, you have a perfect example of why.
It provides no additional type-guarantee.
On the contrary, type declarations on signature boundariesdo provide additional guarantee and thus prevent bugs.
Good news, we're adding them all in v5 when technically possible :)

See#32828 as alternative.

@nicolas-grekas , you mean 1? :)
@xabbuh, so, do you agree that we should close this?

I mean that this situation will happen to all places where we added thestring type - not only on forms.

I would have only done that in places where we explicitly declared support for other data types before. But I also understand the argument about everyone having to do the type cast then (though I wouldn't expect that many people actually use integers as form names).

@nicolas-grekas , yes, I got it. Should we add a note in the BC promise about that then?

Sure, I meant 1. :)
The BC promise is only about minor versions, so that's a bit off topic, but I don't have a better proposal.
PR welcome on the BC promise then, to be clear we don't promise not hard-breaking strict types.