Summary

The playground "never" rule (phpstanPlayground.never) reported false positives suggesting that a method's return type should be changed to never when the method always throws, even when the method is overridden in a child class where it doesn't throw. Changing the parent's return type to never would break the child class.

Changes

• Modified src/Rules/Playground/MethodNeverRule.php to skip reporting for non-private methods in non-final classes, since these methods can be overridden
• Added regression test in tests/PHPStan/Rules/Playground/data/bug-10820.php covering abstract parent with override, non-final class with protected method, private method, and final class
• Updated existing test data in tests/PHPStan/Rules/Playground/data/method-never.php to use final class to preserve existing test coverage

Root cause

The MethodNeverRule did not consider whether a method could be overridden by a subclass. It reported any method that always throws or terminates as needing a never return type, regardless of whether subclasses might override the method with a non-throwing implementation. The fix checks if the method is private or the class is final before suggesting the return type change.

Test

The regression test in bug-10820.php verifies:

• Value::assertString() (public method in abstract non-final class, overridden by child) - no error
• NonFinalBase::doSomething() (protected method in non-final class) - no error
• NonFinalBase::doPrivate() (private method) - error reported (correct)
• FinalClass::doSomething() (public method in final class) - error reported (correct)

Fixes phpstan/phpstan#10820