Hi @ondrejmirtes,

When using treatPhpDocTypesAsCertain: false, a call array_filter shouldn't be reported as useless if the type is coming from phpdoc.

So

if ($this->treatPhpDocTypesAsCertain) {
     $arrayType = $scope->getType($args[0]->value);
} else {
     $arrayType = $scope->getNativeType($args[0]->value);
}

should be used instead of $arrayType = $scope->getType($args[0]->value);

But I don't know if there is something to do in order to not forgot this for others rules,
like changing getType to return the nativeType if treatPhpDocTypesAsCertain is false or exposing another method.
Maybe you would have an idea @staabm, @herndlm or @rajyan ?