/**
  *
  */
 public function testIncrementAge()
 {
     //Create an Object to test with.
     //We're creating an Animal object because the tested functionality is inherited by 'Dog' and 'Cat'
     $animal = new Animal('Animal', 1);
     //Speak once
     $animal->speak("test");
     //Our age should still be 1
     $this->assertEquals(1, $animal->age());
     //Speak twice
     $animal->speak("test");
     //Now our age should be 2
     $this->assertEquals(2, $animal->age());
 }