[TomasVotruba]

Extracted from #827, follow-up to #831.

PHPUnit counts assertions in parent lifecycle methods (setUp(), tearDown(), #[Before], ...) toward every test. A test extending a base class that asserts in setUp() performs assertions, so it must not get #[DoesNotPerformAssertions].

• LifecycleMethodAssertAnalyzer walks parent classes up to PHPUnit/Symfony TestCase, max 5 parents
• a hook overridden without parent::<hook>() hides the parent one
• parent chains with no assert-like text in their files (incl. traits) are skipped before parsing, as parsing with scope costs ~40 ms per file
• results are cached per parent class, so sibling test classes share the chain

Bench

New does_not_perform_assertion_parent_lifecycle_bench.php - 300 test classes on 10 chains of 4 parents, every other chain asserts in its top setUp().

local CPU	main	this PR
does_not_perform_assertion_lifecycle_bench.php	~1.03 s	~1.03 s
does_not_perform_assertion_parent_lifecycle_bench.php	~1.0 s, 100 classes wrongly changed	~1.42 s