Bug: Result of ||/&& is always true/false incorrectly triggered based on docblocks #1254
Description
Summary of a problem or a feature request
If you have a docblock providing details of what a method/function is expecting (instead of just 'mixed') but then try and confirm that the method/function was passed the correct types, then PHPStan reports Result of && is always false.
Code snippet that reproduces the problem
<?php declare(strict_types=1);
// passes
foreach ([123, 'tester', new \DateTimeImmutable(), new stdClass()] as $index => $test) {
print 'Results from index ' . $index . ' = 1: ' . test1($test) . ' 2: '.test2($test).PHP_EOL;
}
/**
* No type hints for programmers, but validation still in place.
* @param mixed $time
* @return string
*/
function test1($time)
{
if (!\is_string($time) && (!$time instanceof \DateTimeInterface)) {
return '[invalid argument]';
}
return 'Matched';
}
/**
* No type hints for programmers, but validation still in place.
* @param mixed $time
* @return string
*/
function test2($time)
{
if (!(\is_string($time) || ($time instanceof \DateTimeInterface))) {
return '[invalid argument]';
}
return 'Matched';
}
/**
* Type hints for programmers, but we still validate just in case.
* @param string|\DateTimeInterface $time
* @return string
*/
function test3($time)
{
if (!\is_string($time) && (!$time instanceof \DateTimeInterface)) {
return '[invalid argument]';
}
return 'Matched';
}
/**
* Type hints for programmers, but we still validate just in case.
* @param string|\DateTimeInterface $time
* @return string
*/
function test4($time)
{
if (!(\is_string($time) || ($time instanceof \DateTimeInterface))) {
return '[invalid argument]';
}
return 'Matched';
}Code output:
Results from index 0 = 1: [invalid argument] 2: [invalid argument]
Results from index 1 = 1: Matched 2: Matched
Results from index 2 = 1: Matched 2: Matched
Results from index 3 = 1: [invalid argument] 2: [invalid argument
PHPStan results:
------ -------------------------------
Line analyzed.php
------ -------------------------------
43 Result of && is always false.
56 Result of || is always true.
------ -------------------------------
(note - apart from the ignorable/strippable docblocks, the functions test1 & test3 and test2 & test4 are identical)
https://phpstan.org/r/f485b932953a743c8737824d902e8252
Expected output
No errors should be reported - PHPStan should not treat the docblock params as set-in-stone (just as 'human suggestions' as humans can make mistakes) and not report this sort of validation as mistakes.