Type is not resolvable via match and instanceof check #10843

Bug report

I feel this is a bug. You can check var type with match syntax like this:

$a = match (true) {
  $date instanceof HelloWorld => 1,
  default => false
};

Now it is clear that if $date is instance of HellowWorld the $a is int, otherwise it is bool. But phpstan doesn't understand that and treats $a always as int|false type.

Code snippet that reproduces the problem

https://phpstan.org/r/f2051cc3-1650-4fee-9634-55c209e2500c

Expected output

Full test code, which should not report an error:

<?php declare(strict_types = 1);

class HelloWorld
{
	public function sayHello(HelloWorld|null $date): int
	{
		$a = match (true) {
			$date instanceof HelloWorld => 1,
			default => false
		};

		if ($date instanceof HelloWorld) {
			return $a;
		}

		throw new Exception('Error');
	}
}

but it is reporting error:

Line 13 Method HelloWorld::sayHello() should return int but returns int|false.

Example is very stupid, and just demonstrates the issue.

Some code works if written with if-else syntax: https://phpstan.org/r/cc487fbd-cbf8-46b6-ad2f-5d28bfb5d9c9

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