[11.x] Allow when() to accept Closure condition parameter

[ziadoz]

This PR allows the standalone when() helper function to accept a Closure as the condition, which brings it into line with the Conditionable trait, which behaves the same way. It's handy when the condition may be expensive or a few lines of code.

I also did notice the helper method here is in the Collections namespace, however the tests suggest it belongs in Support. However I figured this might be a breaking change so I left it where it is, but I can move it if necessary.

[devajmeireles]

Suggested change

	$condition = $condition instanceof Closure ? $condition() : $condition;
	$condition = value($condition);

[devajmeireles]

Good catch! I sent a Laravel-way suggestion.

[zakariaarrid]

Hi @ziadoz ,
You can update the PHPdoc.
* @param \Closure|mixed $condition

[taylorotwell]

Technically a breaking change, though likely rare.

[shaedrich]

I wonder what the value/benefit is in executing a callable within the function but not passing any contextual variables to it that you wouldn't necessarily have outside of the function. In Conditionable, $this is passed to the callback.