Fix phpstan/phpstan#11100: Possibly impure call to function array_map() in pure method - false positive#5197
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…_map() with pure callback - Added array_map to functionMetadata_original.php with hasSideEffects: false - Regenerated resources/functionMetadata.php - New regression test in tests/PHPStan/Rules/Pure/data/bug-11100.php - The root cause was that array_map had no metadata entry, so hasSideEffects() returned "maybe", causing a "Possibly impure" error even when the callback was provably pure. Callback impure points are already propagated separately via processArgs(), so marking array_map itself as side-effect-free is correct.
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Summary
When
array_map()is called with a pure static closure inside a@phpstan-puremethod, PHPStan incorrectly reports "Possibly impure call to function array_map()". This is a false positive becausearray_map()itself has no side effects beyond invoking its callback, and the callback's purity is already tracked separately.Changes
'array_map' => ['hasSideEffects' => false]tobin/functionMetadata_original.phpresources/functionMetadata.phpviabin/generate-function-metadata.phptests/PHPStan/Rules/Pure/data/bug-11100.phpandtests/PHPStan/Rules/Pure/PureMethodRuleTest.phpRoot cause
array_maphad no entry in the function metadata, soNativeFunctionReflectionProviderassigned itTrinaryLogic::createMaybe()forhasSideEffects. This causedSimpleImpurePoint::createFromVariant()to always create a "possibly impure" point for the function call itself, even when the callback argument was provably pure.Since PHPStan already propagates the callback's impure points separately through
NodeScopeResolver::processArgs()(when the callback is immediately invoked), markingarray_mapashasSideEffects: falseis correct — any side effects from the callback are still reported, but the function call itself no longer generates a spurious impure point.This is consistent with how other callback-taking array functions like
array_diff_uassoc,array_diff_ukey,array_udiff, etc. are already marked ashasSideEffects: false.Test
Added
tests/PHPStan/Rules/Pure/data/bug-11100.phpreproducing the original issue: a@phpstan-puremethod callingarray_map()with a pure static closure. The test expects no errors.Fixes phpstan/phpstan#11100