Regression for arrayFilter.strict

[stefanfisk]

There's been a recent regression for arrayFilter.strict where certain array types cause the error to longer be generated. Here's is a playground link which shows a mix of working and broken types https://phpstan.org/r/fbf8aca7-4b24-4591-b982-662087459dcb.

I'm afraid that I don't have time right now to investigate which exact version introduced this issue. But I noticed it after upgrading phpstan/phpstan from 2.1.22 to 2.1.25.

[ondrejmirtes]

Which line is wrong?

[stefanfisk]

Unless I am mistaken all of the calls to array_filter() should have arrayFilter.strict since the parameter is never passed.

[VincentLanglet]

I don't fully understand the purpose of the condition in case of an UnionType

phpstan-strict-rules/src/Rules/Functions/ArrayFilterStrictRule.php

Lines 89 to 110 in d6211c4

	if ($itemType instanceof UnionType) {
	$hasTruthy = false;
	$hasFalsey = false;
	foreach ($itemType->getTypes() as $innerType) {
	$booleanType = $innerType->toBoolean();
	if ($booleanType->isTrue()->yes()) {
	$hasTruthy = true;
	continue;
	}
	if ($booleanType->isFalse()->yes()) {
	$hasFalsey = true;
	continue;
	}
	$hasTruthy = false;
	$hasFalsey = false;
	break;
	}
	if ($hasTruthy && $hasFalsey) {
	return [];
	}

When there is both sure truthy types and sure falsey types in the Union, the error is not reported.

This was added in 8afd4af

So this seems to be a wanted behavior...

[stefanfisk]

I can see the utility in only reporting the error when the type has ambiguous truthiness.

But does it make sense that array_filter([1, 2, '0', new \stdClass()]) doesn't result in an error? '0' will be cast to false and then removed which AFAIU is exactly the sort of case that the rule targets.

[ondrejmirtes]

I guess the code with UnionType could be replaced with Type::getFiniteTypes() call.

[VincentLanglet]

I guess the code with UnionType could be replaced with Type::getFiniteTypes() call.

What would be the idea ?
[1, 2, '0'] will still be ignored if using getFiniteTypes (since 1 is truthy and '0' is falsy) ;
but maybe it's a wanted behavior and this issue should be closed

What is unclear to me at first are the case where you want to ignore the array_filter rules ondrej

• If it's only boolean, it's clear it will keeps true and remove false
• If it's only array, it's clear it will keeps non empty array
• If it's only int, you report an error when it could be considered clear that it will keeps non 0 value
• If it's only string, it make sens to report error because it's unclear if we're removing '' and/or '0'
• If it's null|object, you seems to not want to report an error

Maybe the rule should be ignored if

count(TypeCombinator::intersect($type, $falseyType)->getFiniteTypes()) <= 1