public void TestDetach_WithSelectedCore_WithTwoFragments_ShouldDetachTopFragment()
        {
            ICore     dummyCore            = new SystemCore("A", 100);
            IFragment dummyFragment        = new NuclearFragment("Test", 1);
            IFragment anotherDummyFragment = new NuclearFragment("Test2", 1);

            dummyCore.AttachFragment(dummyFragment);
            dummyCore.AttachFragment(anotherDummyFragment);

            this.testNuclearPowerPlant.AttachCore(dummyCore);
            this.testNuclearPowerPlant.SelectCore("A");

            ICommand testCommand   = new DetachFragmentCommand(this.testNuclearPowerPlant);
            String   actualMessage = testCommand.Execute();

            String expectedMessage = "Successfully detached Fragment Test2 from Core A!";

            Assert.AreEqual(expectedMessage, actualMessage, "DetachFragment command does not work correctly!");
        }