unit_test_AAA

  @Test
  public void testSuccessfulLogin() {
    // Aragnge
    final LoginViewModel vm = new LoginViewModel(environment());

    final TestSubscriber<Void> loginSuccess  = new TestSubscriber<>();
    vm.outputs.loginSuccess().subscribe(loginSuccess);

    vm.inputs.email("hello@kickstarter.com");
    vm.inputs.password("danisawesome");
    
    // Act
    vm.inputs.loginClick();

    // Assert
    loginSuccess.assertValueCount(1);
    koalaTest.assertValues("Login");
  }
}