Fix #14100: Ternary does not narrow type#4915
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ondrejmirtes merged 2 commits into2.1.xfrom Feb 13, 2026
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- Generalized ternary handler in TypeSpecifier to handle all truthy contexts, not just the `$cond ? $expr : false` special case - Converts `$cond ? $a : $b` to equivalent `($cond && $a) || (!$cond && $b)` so existing BooleanOr/BooleanAnd narrowing logic applies - New regression test in tests/PHPStan/Analyser/nsrt/bug-14100.php covering instanceof, is_string/is_int, nested ternaries, and short ternary syntax - Root cause: the ternary handler required `$scope->getType($expr->else)->isFalse()->yes()` which excluded any ternary where the else branch wasn't literally `false` Closes phpstan/phpstan#14100
Automated fix attempt 2 for CI failures.
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Summary
Ternary expressions inside
assert()(and other truthy contexts) did not narrow types. For example,assert($cond ? $x instanceof Foo : $x instanceof Bar)left$xunnarrowed, while the equivalentif/elsewith separateassert()calls worked correctly.Changes
src/Analyser/TypeSpecifier.php(lines 1062-1072) to handle all truthy/falsey contexts, not just the special case where the else branch isfalse$cond ? $a : $bis now converted to the equivalent($cond && $a) || (!$cond && $b), which delegates to the existing BooleanOr/BooleanAnd narrowing logictests/PHPStan/Analyser/nsrt/bug-14100.phpcovering:instanceofchecksis_string/is_int)Root cause
The ternary handler in
TypeSpecifier::specifyTypesInCondition()had two restrictive conditions:!$context->null()— excluded null context (though this didn't matter sinceAssertFunctionTypeSpecifyingExtensionuses truthy context)$scope->getType($expr->else)->isFalse()->yes()— required the else branch to evaluate tofalseThis meant only the pattern
$cond ? $expr : falsewas handled (converted to$cond && $expr). Any ternary where both branches carried meaningful type information (like$cond ? $x instanceof A : $x instanceof B) was silently ignored.The fix removes the
isFalse()restriction and generalizes the conversion to handle both branches, including the negated condition for the else branch.Test
tests/PHPStan/Analyser/nsrt/bug-14100.php— NSRT test verifying thatassert()with ternary conditions correctly narrows types. Coversinstanceof,is_*()functions, nested ternaries, and short ternary syntax.Fixes phpstan/phpstan#14100