Fix phpstan/phpstan#11181: Empty generator "return; yield;" leads to unreachable statement error#5354
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…nerators - Skip bare `yield;` (no key, no value) in getNextUnreachableStatements - This is a valid PHP idiom (`return; yield;`) to create an empty generator - Added regression test in tests/PHPStan/Rules/DeadCode/data/bug-11181.php
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Summary
PHP allows
return; yield;as an idiom to create an empty generator — theyieldmakes PHP treat the function as a generator even though it never executes. PHPStan was incorrectly reporting theyield;as an unreachable statement.Changes
src/Analyser/NodeScopeResolver.php: IngetNextUnreachableStatements(), skipExpressionnodes containing a bareYield_(no key, no value) so they are not flagged as unreachabletests/PHPStan/Rules/DeadCode/data/bug-11181.phpwith test cases forIterator,Generator, anditerablereturn typestestBug11181()intests/PHPStan/Rules/DeadCode/UnreachableStatementRuleTest.phpRoot cause
getNextUnreachableStatements()already skips certain benign statements after terminating code (Nop,InlineHTML, early-bound declarations). It did not account for bareyield;statements, which serve as generator markers in PHP and are a well-known idiom for creating empty generators.Test
The regression test covers three variants of the
return; yield;pattern with different return type hints (Iterator,Generator,iterable). All should analyse without errors.Fixes phpstan/phpstan#11181