Bug report

Call to function is_subclass_of() with object and class-string is reported as always being evaluated as true, even if it can't possibly know the type of the object given nor the class described by the class-string.

It also happens with class-string and class-string.

Using PHP 8.1.13 & PHPStan 1.9.2

Code snippet that reproduces the problem

https://phpstan.org/r/fc3cdcea-02db-4aba-b64d-9da9170288fa

https://phpstan.org/r/9103b780-22c7-4c38-9dd7-f8933540ceff

Expected output

PHPStan should not report any error if it can't know whether one is subclass of the other before execution.

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It helped me a lot defining more precisely the types for my app.