Fix phpstan/phpstan#9455: Bug: False report Cannot call method getId() on A|null

[phpstan-bot]

Summary

When a null check on a method call result was stored in a boolean variable (e.g., $hasA = $b->getA() !== null), and that variable was later used in an if condition, PHPStan failed to narrow the type of $b->getA() inside the branch. The inline equivalent (if ($b->getA() !== null)) worked correctly.

Changes

• Added MethodCall and Expr\StaticCall to the allowed expression types in processSureTypesForConditionalExpressionsAfterAssign() and processSureNotTypesForConditionalExpressionsAfterAssign() in src/Analyser/ExprHandler/AssignHandler.php
• Added regression test in tests/PHPStan/Analyser/nsrt/bug-9455.php

Root cause

When PHPStan processes an assignment like $hasA = $b->getA() !== null, it creates ConditionalExpressionHolder objects that record type narrowing to apply when the assigned variable is later used in a condition. However, the methods processSureTypesForConditionalExpressionsAfterAssign and processSureNotTypesForConditionalExpressionsAfterAssign only allowed Variable, PropertyFetch, ArrayDimFetch, and FuncCall expressions to create these holders — MethodCall and StaticCall were filtered out. This meant that type narrowing from method call null checks (like $b->getA() !== null) was never stored and thus never applied when the boolean variable was checked.

Test

The regression test verifies that $b->getA() is correctly narrowed to Bug9455\A (not Bug9455\A|null) inside an if ($hasA) block where $hasA = $b->getA() !== null.

Fixes phpstan/phpstan#9455