is_subclass_of(string, string) generates invalid prediction

[thg2k]

Bug report

Erroneus report: Result of && is always false

Clearly that is not correct as demonstrated by the two calls below.

Code snippet that reproduces the problem

https://phpstan.org/r/99bd746d-80c2-4eb1-8506-2840c6fd5089

Expected output

No errors.

[vovmog]

also
https://phpstan.org/r/960adf22-fd32-49d1-a076-c332d75530b4

[phpstan-bot]

@vovmog After the latest commit in dev-master, PHPStan now reports different result with your code snippet:

@@ @@
-21: Call to an undefined method object::toArray().
+No errors

[enumag]

It seems this was also fixed by phpstan/phpstan-src#1039.

[ondrejmirtes]

Fixed: phpstan/phpstan-src@73f14db

[ondrejmirtes]

The first example still reports an error.

[ondrejmirtes]

This gives more insight into the types involved: https://phpstan.org/r/4399bb2a-cf2b-4038-9716-97cac1e647d4

[VincentLanglet]

This can be simplified to https://phpstan.org/r/2b8bb6fd-da7d-4f2c-9318-246cf0ce29a1

is_subclass_of(class-string, string) is always true for PHPStan

I would have expected to find a DynamicReturnTypeExtension, but all I found is IsSubclassOfFunctionTypeSpecifyingExtension. I never worked with TypeSpecifyingExtension but to me it's supposed to determine the type of the parameter based on the return type ; and not the opposite...

[mvorisek]

would ge great if this count be fixed