API Resource $this->when condition not respected

I'm struggling to figure out what's going on here.

In the example below $this->relation does not exist, calling $this->relation->anotherRelation fails (which it should) but the condition for $this->when is false

$request->user()->can('permission') && $this->has_other_resource = false

Basically i'd like to know why this code is being called: new OtherResource($this->relation->anotherRelation)

public function toArray($request)
{
		return [
				'some_key' => 'some_value',
				'another_key' => $this->when(
						$request->user()->can('permission') && $this->has_other_resource, 
						new OtherResource($this->relation->anotherRelation)
				)
		];
}