Incorrect type refinement with in_array(..., strict: true) #5759
Description
Bug report
Somewhere between 0.12.94 and 0.12.99, a correctly-reachable bit of code following an in_array(const-enum, array-of-const-enums, true) check started leading to incorrectly marking the value as unreachable. Using \PHPStan\dumpType($array) shows the correct set of possible values entering the function and conditional.
I suspect this is in some way related to the recent improvements which removed the hard limit of 8 values in constant scalar arrays, but haven't done a deep dive. It does occur (as demonstrated below) in smaller value sets, so possibly it's been a latent issue that only just started happening on my larger enums.
Update: poking around a bit more, I observed that without in_array(..., strict: true), I do not receive the unreachable code error. However, the checked value is still not refined out of the variable.
Code snippet that reproduces the problem
https://phpstan.org/r/2af7eca1-73d9-4489-a107-897f77d04e44
https://phpstan.org/r/437803d5-e64c-4149-9715-8805052141eb
Note the code I discovered this with is more complex (more constants, other conditionals, etc), but this seems to be the simplest reproduce case. The updated snippet reveals the issue is specific to strict checks of array contents.
Expected output
No "unreachable statement" error; dumpTypes should have Dumped type: array<2|3>