Bug report
Looks like PHPStan thinks there are four code paths may be executed:
$fooCollection->add(Foo::class)
$fooCollection->add(Bar::class)
$barCollection->add(Foo::class)
$barCollection->add(Bar::class)
But actually there are only two paths, $fooCollection->add(Foo::class) and $barCollection->add(Bar::class).
Code snippet that reproduces the problem
https://phpstan.org/r/4a41044b-cdcb-4466-9043-a9c050420d4d
Expected output
No errors.