public void OnKeyUpUnlockTest() { var vm = new MainViewModel(); var arg = Mock.Create<KeyEventArgs>(Behavior.Loose); Mock.Arrange(() => arg.Key).Returns(Key.Enter); var unlockCommandExecuted = false; Mock.Arrange(() => vm.UnlockCommand.Execute(null)).DoInstead(() => unlockCommandExecuted = true); // Act vm.OnKeyUpUnlock(null, arg); // Assert Assert.IsTrue(unlockCommandExecuted); }