Fix GH-16814: MessageFormatter::format throws an error on invalid arr…

[devnexen]

…ay element.

[iluuu1994]

I believe this will implicitly modify the array. Can we skip the entire iteration when the parameter is unsed?

[nielsdos]

Honestly, I think throwing away the exception is pretty bad. What if the entry is actually used and the __toString() legitimately throws? I also think this isn't a bug in the first place:
If the key is used then we should throw, but if it isn't used then why is it passed in the first place?
If we were a statically typed language we'd have a typehint array<string> and the coercion would fail upfront.

[devnexen]

I kind of agree with you (one of the reasons I keep it as draft), I was just trying to see what s possible but ultimately looking at the code so many times, it is mostly good as is..

[iluuu1994]

I agree that exceptions should not be discarded. What I was suggesting is trying to skip the coercion to string in the first place. But as Niels has mentioned, IMO this is definitely not a bug, and might not even be a worthwhile feature.