Assignment of empty SplObjectStorage

[enumag]

There seems to be some issue with SplObjectStorage - I can't assign empty SplObjectStorage to an annotated property. Note that this works just fine for other generic types since b26deb4.

https://psalm.dev/r/747947d7b6

[psalm-github-bot]

I found these snippets:

https://psalm.dev/r/747947d7b6

<?php declare(strict_types = 1);

class HelloWorld
{
    /**
	 * @var SplObjectStorage<DateTimeImmutable, null>
	 */
	public SplObjectStorage $dates;
	
	public function __construct()
	{
		$this->dates = new SplObjectStorage();
	}
}

Psalm output (using commit 7dba9bc):

ERROR: PropertyTypeCoercion - 12:18 - $this->dates expects 'SplObjectStorage<DateTimeImmutable, null>',  parent type 'SplObjectStorage<object, mixed>' provided

[muglug]

It's because the constructor doesn't take templated params, so there's nothing to be considered empty. I think the only way around this is to hack things a bit.

[ondrejmirtes]

I think it's sufficient to add the constructor with type variable parameters.