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 | 6.0.7Phan 6.0.7 php-ast version 1.1.3 PHP version used to run Phan: 8.5.9 | Pass | No diagnostics reported. |
| phpstan | 2.2.8PHPStan - PHP Static Analysis Tool 2.2.8 | Pass reported Lv.4+ | regressions_optional_extra_key_is_list.php:24: Call to function array_is_list() with array{0: int, a?: string} will always evaluate to false. [identifier=function.impossibleType] [reported-from-level=4]With strict-rulesregressions_optional_extra_key_is_list.php:24: Call to function array_is_list() with array{0: int, a?: string} will always evaluate to false. [identifier=function.impossibleType] |
| psalm | 6.16.1Psalm 6.16.1@f1f5de594dc76faf8784e02d3dc4716c91c6f6ac next: 7.0.0-beta19 |
Pass | regressions_optional_extra_key_is_list.php:24: Type array{0: int, a?: string} for $b is never list<mixed> [TypeDoesNotContainType] |
| mago | 1.46.0mago 1.46.0 | Fail | No diagnostics reported. Expectation diffLine 24: Expected 1 error(s) |
| mir | 0.70.1mir 0.70.1 | Pass | No diagnostics reported. |
| phpantom | 0.9.0phpantom_lsp 0.9.0 | Pass | No diagnostics reported. |
| intelephense | 1.18.5intelephense 1.18.5 | Pass | No diagnostics reported. |
| phpy | 0.2.0phpy 0.2.0 | Pass | No diagnostics reported. |
| qodana | 262.8665.325Qodana 262.8665.325 | 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 | 0.1.5steins 0.1.5 (2026-08-12 revision 39b4cc1) | Pass | No diagnostics reported. |
| phpstan-strict | 2.2.8PHPStan - PHP Static Analysis Tool 2.2.8 | Pass | regressions_optional_extra_key_is_list.php:24: Call to function array_is_list() with array{0: int, a?: string} will always evaluate to false. [identifier=function.impossibleType] |
| psalm-next | 7.0.0-beta19Psalm 7.0.0-beta19@7e751c06a756fa64dc4c759c09fe4a173afcb433 | 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<phpstan>: [0 => 1] satisfies the shape and is a list, so the check is maybe-true not always-false (#14938) // E<phpstan-strict>: same always-false verdict // E<psalm>: TypeDoesNotContainType, reported as never list // E<mago>: impossible-type-comparison in 1.19
echo "reached at runtime when \$b === [0 => 1]\n";
}
}
optionalExtraKeyIsList([0 => 1]);