Comparison operation always true on modified array by reference

[JAZ-013]

Hi. First of all, sorry, I'm incredibly new to PHPStan and a VERY old school PHP developer (20+ years). I'm in the process of apply static analysis to some old code to bring it up to date. Most issues are being dealt with fine, but I came across this issue in a library I wrote that uses sockets and I'm not sure it's correct(??). Or can someone explain to me why this is considered invalid?

<?php declare(strict_types = 1);

class HelloWorld
{
	public function sayHello(): void
	{
		$socket = socket_create(AF_INET, SOCK_STREAM, 0);
		if($socket === false) return;
		$read = [$socket];
		$write = null;
		$except = null;
		socket_select($read, $write, $except, 0, 1);
		if(count($read) > 0){
			echo 'ready to read';
		}
	}
}

You can paste this code into the playground on phpstan.org with at least LEVEL4 and it'll give the error:

Comparison operation ">" between 1 and 0 is always true.

However, the purpose of socket_select is to modify the $read array, so it will more than often than not, be empty at this point. Why is PHPStan throwing this error when the array is passed by reference to the socket_select function? What would be a valid work-around for this case? Is dropping the rule level, or adding an ignore annotation the only option?

Thanks. I'm really just trying to wrap my head around some of the rules here so bare with me. ;)

[ondrejmirtes]

Hi, this is a bug. I fixed it: phpstan/phpstan-src@24c5249

[JAZ-013]

Oh cool. Thanks for sorting that out. :)