PHPUnit, mocked interfaces, and instanceof

Question

Sometimes in my code, I'll check to see if a particular object implements an interface:

if ($instance instanceof Interface) {};

However, creating mocks of said interface in PHPUnit, I can't seem to pass that test.

 // class name is Mock_Interface_431469d7, does not pass above check
 $instance = $this->getMock('Interface'); 

I understand that having a class named Interface is different from a class implementing Interface, but I'm not sure how to get deal with this.

Am I forced to mock a concrete class that implements Interface? Wouldn't that defeat the purpose of using an interface for portability?

Thanks

Answer 1

there is also assertInstanceOf as of 3.5.0

Example:

$this->assertInstanceOf('\Models\User', $this->userService->findById(1));