Null coalesce non-null result implies the caller not to be null - not reflected in consequent conditions

[janedbal]

Feature request

See snippet: https://phpstan.org/r/bb7805f4-89bf-42e7-825b-d4984041c656, it would be nice if phpstan would understand this correlation.

[neclimdul]

Think I ran into the same issue with a property. Ran into this implementing the PSR-7 message interface which will close/detach the internal resource leading to some weird object states where the internal resource is no longer set.

Here's a bit of a contrived example demonstrating it using a generator.
https://phpstan.org/r/20e1698e-7e49-4793-a542-1640e03e7c6f

[phpstan-bot]

@neclimdul After the latest push in 2.2.x, PHPStan now reports different result with your code snippet:

@@ @@
-16: Cannot call method next() on Generator<int, string, mixed, mixed>|null.
+No errors

[phpstan-bot]

Closed via merging phpstan/phpstan-src#4995