public void errors_retrieving_data_are_surfaced()
{
var api = new ApiMock();
api
.When(x => x.GetDinosaur(It.IsAny <int>()))
.Return(Observable.Throw <Dinosaur>(new InvalidOperationException("foo")));
var sut = new DinosaurDetailsViewModel(
42,
new BitmapLoaderMock(),
api,
CurrentThreadScheduler.Instance);
sut
.Activator
.Activate();
Assert.NotNull(sut.Error);
Assert.Equal("foo", sut.Error.Exception.Message);
api
.When(x => x.GetDinosaur(It.IsAny <int>()))
.Return(Observable.Return(default(Dinosaur)));
sut
.Error
.RetryCommand
.Execute(null);
Assert.Null(sut.Error);
}
public void errors_saving_data_are_surfaced()
{
var scheduler = new TestScheduler();
var api = new ApiMock();
api
.When(x => x.SaveDinosaur(It.IsAny <Dinosaur>()))
.Return(Observable.Throw <Unit>(new InvalidOperationException("foo")));
var sut = new DinosaurDetailsViewModel(
42,
new BitmapLoaderMock(),
api,
scheduler);
sut
.Activator
.Activate();
sut.Name = "Barney";
sut.Weight = "42";
scheduler.AdvanceByMs(2001);
Assert.NotNull(sut.Error);
Assert.Equal("foo", sut.Error.Exception.Message);
api
.When(x => x.SaveDinosaur(It.IsAny <Dinosaur>()))
.Return(Observable.Return(Unit.Default));
sut
.Error
.RetryCommand
.Execute(null);
scheduler.AdvanceByMs(1);
Assert.Null(sut.Error);
}
public void busy_flag_remains_true_whilst_saving_data()
{
var scheduler = new TestScheduler();
var api = new ApiMock();
var saveDinosaur = new Subject <Unit>();
api
.When(x => x.SaveDinosaur(It.IsAny <Dinosaur>()))
.Return(saveDinosaur);
var sut = new DinosaurDetailsViewModel(
42,
new BitmapLoaderMock(),
api,
scheduler);
sut
.Activator
.Activate();
sut.Name = "Barney";
sut.Weight = "42";
scheduler.AdvanceByMs(2001);
Assert.True(sut.IsBusy);
saveDinosaur.OnCompleted();
scheduler.AdvanceByMs(1);
Assert.False(sut.IsBusy);
}
public void busy_flag_remains_true_whilst_deleting_data()
{
var api = new ApiMock();
var deleteDinosaur = new Subject <Unit>();
api
.When(x => x.DeleteDinosaur(It.IsAny <int>()))
.Return(deleteDinosaur);
var sut = new DinosaurDetailsViewModel(
42,
new BitmapLoaderMock(),
api,
CurrentThreadScheduler.Instance);
sut
.Activator
.Activate();
using (sut.ConfirmDeleteInteraction.RegisterHandler(context => context.SetOutput(true)))
{
sut
.DeleteCommand
.Execute()
.Subscribe();
Assert.True(sut.IsBusy);
}
deleteDinosaur.OnCompleted();
Assert.False(sut.IsBusy);
}
public void data_cannot_be_deleted_if_the_auditing_system_is_unavailable()
{
var api = new ApiMock();
var isAuditingAvailable = new BehaviorSubject <bool>(true);
api
.When(x => x.IsAuditingAvailable)
.Return(isAuditingAvailable);
var sut = new DinosaurDetailsViewModel(
42,
new BitmapLoaderMock(),
api,
CurrentThreadScheduler.Instance);
sut
.Activator
.Activate();
Assert.True(sut.DeleteCommand.CanExecute.FirstAsync().Wait());
isAuditingAvailable.OnNext(false);
Assert.False(sut.DeleteCommand.CanExecute.FirstAsync().Wait());
isAuditingAvailable.OnNext(true);
Assert.True(sut.DeleteCommand.CanExecute.FirstAsync().Wait());
}
public void saves_are_throttled_to_two_seconds()
{
var scheduler = new TestScheduler();
var api = new ApiMock();
var sut = new DinosaurDetailsViewModel(
42,
new BitmapLoaderMock(),
api,
scheduler);
sut
.Activator
.Activate();
scheduler.AdvanceByMs(2000);
sut.Name = "Barney";
scheduler.AdvanceByMs(500);
sut.Name = "Barney the Dinosaur";
scheduler.AdvanceByMs(500);
sut.Weight = "42";
scheduler.AdvanceByMs(1999);
api
.Verify(x => x.SaveDinosaur(It.IsAny <Dinosaur>()))
.WasNotCalled();
scheduler.AdvanceByMs(1);
api
.Verify(x => x.SaveDinosaur(It.IsAny <Dinosaur>()))
.WasCalledExactlyOnce();
}
public void data_is_saved_immediately_upon_deactivation_even_if_two_seconds_has_not_elapsed_since_last_change()
{
var scheduler = new TestScheduler();
var api = new ApiMock();
var sut = new DinosaurDetailsViewModel(
42,
new BitmapLoaderMock(),
api,
scheduler);
sut
.Activator
.Activate();
sut.Name = "Barney";
scheduler.AdvanceByMs(1);
api
.Verify(x => x.SaveDinosaur(It.IsAny <Dinosaur>()))
.WasNotCalled();
sut
.Activator
.Deactivate();
scheduler.AdvanceByMs(1);
api
.Verify(x => x.SaveDinosaur(It.IsAny <Dinosaur>()))
.WasCalledExactlyOnce();
}
public void data_is_saved_two_seconds_after_image_data_is_modified()
{
var scheduler = new TestScheduler();
var api = new ApiMock();
var sut = new DinosaurDetailsViewModel(
42,
new BitmapLoaderMock(),
api,
scheduler);
sut
.Activator
.Activate();
scheduler.AdvanceByMs(2000);
sut.Weight = "42";
sut.ImageData = new byte[] { 1, 2, 3 };
scheduler.AdvanceByMs(1999);
api
.Verify(x => x.SaveDinosaur(It.IsAny <Dinosaur>()))
.WasNotCalled();
scheduler.AdvanceByMs(1);
api
.Verify(x => x.SaveDinosaur(It.IsAny <Dinosaur>()))
.WasCalledExactlyOnce();
}
public void retrieved_data_is_used_to_populate_the_initial_values()
{
var scheduler = new TestScheduler();
var dinosaur = new Dinosaur("Barney", 13, new byte[] { 1, 2, 3 });
var api = new ApiMock();
api
.When(x => x.GetDinosaur(42))
.Return(Observable.Return(dinosaur));
var sut = new DinosaurDetailsViewModel(
42,
new BitmapLoaderMock(),
api,
scheduler);
sut
.Activator
.Activate();
scheduler.AdvanceByMs(1);
Assert.Equal("Barney", sut.Name);
Assert.Equal("13", sut.Weight);
Assert.Equal(13, sut.ValidatedWeight.Value);
Assert.NotNull(sut.Image);
}
public void data_is_not_retrieved_upon_construction()
{
var api = new ApiMock();
var sut = new DinosaurDetailsViewModel(
42,
new BitmapLoaderMock(),
api,
CurrentThreadScheduler.Instance);
api
.Verify(x => x.GetDinosaur(It.IsAny <int>()))
.WasNotCalled();
}
public void data_is_retrieved_upon_activation()
{
var api = new ApiMock();
var sut = new DinosaurDetailsViewModel(
42,
new BitmapLoaderMock(),
api,
CurrentThreadScheduler.Instance);
sut
.Activator
.Activate();
api
.Verify(x => x.GetDinosaur(42))
.WasCalledExactlyOnce();
}
public void invalid_weights_are_rejected()
{
var sut = new DinosaurDetailsViewModel(
42,
new BitmapLoaderMock(),
new ApiMock(),
CurrentThreadScheduler.Instance);
sut
.Activator
.Activate();
sut.Weight = "42a";
Assert.False(sut.ValidatedWeight.IsValid);
Assert.Equal("'42a' is not a valid weight. Please enter whole numbers only.", sut.ValidatedWeight.Error);
}
public void data_is_not_saved_if_it_is_invalid()
{
var api = new ApiMock();
var sut = new DinosaurDetailsViewModel(
42,
new BitmapLoaderMock(),
api,
CurrentThreadScheduler.Instance);
sut
.Activator
.Activate();
sut.Weight = "42a";
api
.Verify(x => x.SaveDinosaur(It.IsAny <Dinosaur>()))
.WasNotCalled();
}
public void memory_is_reclaimed_after_deactivation()
{
//
// IMPORTANT: if you're observing failures in this test, try running it in release mode without a debugger attached.
//
// The SUT will subscribe to this subject, so we hold a reference to it so that it can't be GC'd.
var isAuditingAvailable = new Subject <bool>();
var api = new ApiMock();
api
.When(x => x.IsAuditingAvailable)
.Return(isAuditingAvailable);
var sut = new DinosaurDetailsViewModel(
42,
new BitmapLoaderMock(),
api,
CurrentThreadScheduler.Instance);
sut
.Activator
.Activate();
var weakSut = new WeakReference(sut);
sut = null;
GC.Collect();
GC.WaitForPendingFinalizers();
GC.Collect();
Assert.True(weakSut.IsAlive);
// Deactivation is when the SUT should detach subscriptions and therefore become eligible for collection.
((DinosaurDetailsViewModel)weakSut.Target)
.Activator
.Deactivate();
GC.Collect();
GC.WaitForPendingFinalizers();
GC.Collect();
Assert.False(weakSut.IsAlive);
}
public void changing_the_image_data_updates_the_image()
{
var sut = new DinosaurDetailsViewModel(
42,
new BitmapLoaderMock(),
new ApiMock(),
CurrentThreadScheduler.Instance);
sut
.Activator
.Activate();
var images = sut
.WhenAnyValue(x => x.Image)
.CreateCollection(ImmediateScheduler.Instance);
sut.ImageData = new byte[] { 1, 2, 3 };
sut.ImageData = new byte[] { 4, 5, 6 };
Assert.Equal(3, images.Count);
}
public void valid_weights_are_accepted()
{
var scheduler = new TestScheduler();
var sut = new DinosaurDetailsViewModel(
42,
new BitmapLoaderMock(),
new ApiMock(),
scheduler);
sut
.Activator
.Activate();
scheduler.AdvanceByMs(1);
sut.Weight = "42";
scheduler.AdvanceByMs(1);
Assert.True(sut.ValidatedWeight.IsValid);
Assert.Equal(42, sut.ValidatedWeight.Value);
}
public void data_is_deleted_if_user_confirms()
{
var api = new ApiMock();
var sut = new DinosaurDetailsViewModel(
42,
new BitmapLoaderMock(),
api,
CurrentThreadScheduler.Instance);
using (sut.ConfirmDeleteInteraction.RegisterHandler(context => context.SetOutput(true)))
{
sut
.DeleteCommand
.Execute()
.Subscribe();
}
api
.Verify(x => x.DeleteDinosaur(It.IsAny <int>()))
.WasCalledExactlyOnce();
}
public void busy_flag_remains_true_whilst_retrieving_data()
{
var api = new ApiMock();
var getDinosaur = new Subject <Dinosaur>();
api
.When(x => x.GetDinosaur(It.IsAny <int>()))
.Return(getDinosaur);
var sut = new DinosaurDetailsViewModel(
42,
new BitmapLoaderMock(),
api,
CurrentThreadScheduler.Instance);
sut
.Activator
.Activate();
Assert.True(sut.IsBusy);
getDinosaur.OnCompleted();
Assert.False(sut.IsBusy);
}
public void errors_deleting_data_are_surfaced()
{
var api = new ApiMock();
api
.When(x => x.DeleteDinosaur(It.IsAny <int>()))
.Return(Observable.Throw <Unit>(new InvalidOperationException("foo")));
var sut = new DinosaurDetailsViewModel(
42,
new BitmapLoaderMock(),
api,
CurrentThreadScheduler.Instance);
sut
.Activator
.Activate();
using (sut.ConfirmDeleteInteraction.RegisterHandler(context => context.SetOutput(true)))
{
sut
.DeleteCommand
.Execute()
.Subscribe(
_ => { },
_ => { });
Assert.NotNull(sut.Error);
Assert.Equal("foo", sut.Error.Exception.Message);
api
.When(x => x.DeleteDinosaur(It.IsAny <int>()))
.Return(Observable.Return(Unit.Default));
sut
.Error
.RetryCommand
.Execute(null);
Assert.Null(sut.Error);
}
}