Fix phpstan/phpstan#13705: Adding elements to empty array in while loop does not result in array being recognized as potentially non-empty for in_array#5290
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When `count($arr) < $rangeVar` was used as a while loop condition (or
similar), the TypeSpecifier would incorrectly narrow the array to
`array{}` inside the loop body. This happened because
`specifyTypesForCountFuncCall` treated an IntegerRangeType sizeType
in falsey context as "count NOT in range", which is stricter than
the actual semantic "count < some value within the range".
Skip specifyTypesForCountFuncCall entirely when context is falsey
and the left operand is an IntegerRangeType, since the correct
narrowing cannot be expressed with the current sizeType abstraction.
Update test expectations in bug-4700 and bug11480 which relied on
the previous unsound over-narrowing behavior.
Fixes phpstan/phpstan#13705
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Mar 25, 2026
…an#5059) Co-authored-by: Claude Opus 4.6 <[email protected]>
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This PR fixes phpstan/phpstan#13705.
Summary
When
count($array) < $variable(where$variablehas a range type likeint<1, 42>) was used as a while loop condition, PHPStan incorrectly narrowed the array type toarray{}inside the loop body. This caused false positives within_array()and similar functions that depend on the array being potentially non-empty.Root cause
The condition
count($codes) < $quantityis internally transformed to!($quantity <= count($codes)). TheSmallerOrEqualhandler inTypeSpecifiercomputes asizeTypefrom the left operand and passes it tospecifyTypesForCountFuncCall. In the falsey context (negated byBooleanNot), this function interpretssizeType = int<1, 42>as "count is NOT in int<1,42>", concluding count must be 0. But the actual semantic is "count < $quantity where $quantity is somewhere in int<1,42>" — count could easily be non-zero (e.g., count=3 when $quantity=5).Fix
Skip
specifyTypesForCountFuncCallwhen the context is falsey AND the left operand is anIntegerRangeType. The sound narrowing for this case cannot be expressed with the current sizeType abstraction, so no narrowing is better than unsound narrowing.Two existing test files (
bug-4700.php,bug11480.php) had expectations that relied on the previous unsound over-narrowing and have been updated.Test plan
tests/PHPStan/Analyser/nsrt/bug-13705.phpcovering while loop, do-while loop, and simple while loop casesbug-4700.phpandbug11480.php