array{0: int, a?: string} admits the value [0 => 1] (the optional string key a is
absent), and array_is_list([0 => 1]) === true. So array_is_list($b) is maybe-true,
not "always false", and the list branch is reachable. This is the second reproduction
from phpstan#14938 — the optional-extra-key variant of the optional-key family (see
regressions_optional_key_shape_is_list.php for the base case).
References:
- PHPStan phpstan#14938 (fix: phpstan-src#6025)
- Cross-tool survey phpstan#14939| Analyzer | Version | Result | Diagnostics |
|---|---|---|---|
| phan | 6.0.10Phan 6.0.10 php-ast version 1.1.3 PHP version used to run Phan: 8.5.11 | Pass | No diagnostics reported. |
| phpstan | 2.3.1PHPStan - PHP Static Analysis Tool 2.3.1 | Pass | No diagnostics reported. |
| psalm | 6.20.0Psalm 6.20.0@804f03c0c183d149fcd4b8c7c0c9b3fbf836d34c next: 7.0.0-rc2 |
Pass | regressions_optional_extra_key_is_list.php:24: Type array{0: int, a?: string} for $b is never list<mixed> [TypeDoesNotContainType] |
| mago | 1.57.0mago 1.57.0 | Pass | No diagnostics reported. |
| mir | 0.87.0mir 0.87.0 | Pass | regressions_optional_extra_key_is_list.php:24: RedundantCondition: Condition is always false, so the then branch is never reached [MIR0400] |
| phpantom | 0.11.1phpantom_lsp 0.11.1 | Pass | No diagnostics reported. |
| intelephense | 1.18.5intelephense 1.18.5 | Pass | No diagnostics reported. |
| phpactor | 2026.10.07.0Phpactor 2026.10.07.0 | Pass | No diagnostics reported. |
| phpy | 1.0.19409phpy 1.0.19409 | Pass | No diagnostics reported. |
| qodana | 262.10968.76PhpStorm 262.10968.76 | Pass | No diagnostics reported. |
| noverify | 0.5.5NoVerify, version 0.5.5: built on: 2025.04.22 14:36:46 OS: r-kuchinskas arm64 Commit: 4774b82f8adc53fbef38f95e97af4b953b4d1529 | Pass | regressions_optional_extra_key_is_list.php:22: param $b miss matched with phpdoc type <<array{0: int, a?: string}>> [funcParamTypeMissMatch] |
| steins | 0.1.8steins 0.1.8 (2026-09-21 revision 76306a9) | Pass | No diagnostics reported. |
| phpstan-strict | 2.3.1PHPStan - PHP Static Analysis Tool 2.3.1 | Pass | No diagnostics reported. |
| psalm-next | 7.0.0-rc2Psalm 7.0.0-rc2@20339e3fe5b8d03bcd8061030eb2a83ad50e5783 | Pass | regressions_optional_extra_key_is_list.php:24: Type array{0: int, a?: string} for $b is never list<mixed> [TypeDoesNotContainType] |
<?php
declare(strict_types=1);
namespace Conformance\Tests\RegressionsOptionalExtraKeyIsList;
/**
* Optional extra non-list key stays list-compatible.
*
* `array{0: int, a?: string}` admits the value `[0 => 1]` (the optional string key `a` is
* absent), and `array_is_list([0 => 1]) === true`. So `array_is_list($b)` is maybe-true,
* not "always false", and the list branch is reachable. This is the second reproduction
* from phpstan#14938 — the optional-extra-key variant of the optional-key family (see
* regressions_optional_key_shape_is_list.php for the base case).
*
* References:
* - PHPStan https://github.com/phpstan/phpstan/issues/14938 (fix: phpstan-src#6025)
* - Cross-tool survey https://github.com/phpstan/phpstan/discussions/14939
*/
/** @param array{0: int, a?: string} $b */
function optionalExtraKeyIsList(array $b): void // E<noverify>: NoVerify does not parse array shape syntax and flags the annotation itself
{
if (array_is_list($b)) { // E<psalm>: TypeDoesNotContainType, reported as never list // E<pzoom>: same TypeDoesNotContainType as Psalm // E<mir>: RedundantCondition — collapses the check. PHPStan reported always-false through 2.2.8 (#14938) and is silent since 2.2.9. Mago reported impossible-type-comparison in 1.19 and is silent since 1.43
echo "reached at runtime when \$b === [0 => 1]\n";
}
}
optionalExtraKeyIsList([0 => 1]);