public void ensure_initialized_fails_if_not_yet_initialized()
{
var sut = new InitializationGuard(() => Observable.Return(Unit.Default));
var ex = Assert.Throws <InitializationException>(() => sut.EnsureInitialized());
Assert.Equal("Not yet initialized.", ex.Message);
}
public void initialization_only_executes_once_even_when_there_are_multiple_initialization_attempts_at_once()
{
var count = 0;
var init = new Subject <Unit>();
var sut = new InitializationGuard(() => Observable.Start(() => { ++count; }, ImmediateScheduler.Instance).SelectMany(_ => init));
Assert.Equal(0, count);
sut
.Initialize()
.Subscribe()
.Dispose();
sut
.Initialize()
.Subscribe()
.Dispose();
sut
.Initialize()
.Subscribe()
.Dispose();
init.OnCompleted();
Assert.Equal(InitializationGuardState.Initialized, sut.State);
Assert.Equal(1, count);
}
public void state_resets_to_uninitialized_if_initialization_fails()
{
var sut = new InitializationGuard(() => Observable.Throw <Unit>(new InvalidOperationException()));
sut
.Initialize()
.Subscribe();
Assert.Equal(InitializationGuardState.Uninitialized, sut.State);
}
public void an_initialized_guard_has_a_state_of_initialized()
{
var sut = new InitializationGuard(() => Observable.Return(Unit.Default));
sut
.Initialize()
.Subscribe();
Assert.Equal(InitializationGuardState.Initialized, sut.State);
}
public void an_initializing_guard_has_a_state_of_initializing()
{
var sut = new InitializationGuard(() => Observable.Never <Unit>());
sut
.Initialize()
.Subscribe();
Assert.Equal(InitializationGuardState.Initializing, sut.State);
}
public void ensure_initialized_succeeds_if_initialized()
{
var sut = new InitializationGuard(() => Observable.Return(Unit.Default));
sut
.Initialize()
.Subscribe();
sut.EnsureInitialized();
}
public void error_propagates_if_initialization_fails()
{
var sut = new InitializationGuard(() => Observable.Throw <Unit>(new InvalidOperationException("Whatever")));
Exception exception = null;
sut
.Initialize()
.Subscribe(
_ => { },
ex => exception = ex);
Assert.NotNull(exception);
Assert.Equal("Whatever", exception.Message);
}
public void disposing_disconnects_the_initialization_pipeline()
{
var init = new Subject <Unit>();
var sut = new InitializationGuard(() => init);
var initialized = false;
sut
.Initialize()
.Subscribe(_ => initialized = true);
sut.Dispose();
init.OnCompleted();
Assert.False(initialized);
}
public void initialization_can_be_reattempted_if_it_fails()
{
var attempt = 0;
var sut = new InitializationGuard(
() => Observable
.Start(() => ++ attempt, ImmediateScheduler.Instance)
.Select(a => a == 2)
.SelectMany(succeed => succeed ? Observable.Return(Unit.Default) : Observable.Throw <Unit>(new InvalidOperationException())));
sut
.Initialize()
.Subscribe();
Assert.Equal(InitializationGuardState.Uninitialized, sut.State);
sut
.Initialize()
.Subscribe();
Assert.Equal(InitializationGuardState.Initialized, sut.State);
}
public void initialization_pipeline_must_complete_before_being_considered_done()
{
var initialize = new Subject <Unit>();
var sut = new InitializationGuard(() => initialize);
sut
.Initialize()
.Subscribe();
Assert.Equal(InitializationGuardState.Initializing, sut.State);
initialize.OnNext(Unit.Default);
Assert.Equal(InitializationGuardState.Initializing, sut.State);
initialize.OnNext(Unit.Default);
Assert.Equal(InitializationGuardState.Initializing, sut.State);
initialize.OnCompleted();
Assert.Equal(InitializationGuardState.Initialized, sut.State);
}
public void initialization_only_executes_once_if_successful()
{
var count = 0;
var sut = new InitializationGuard(() => Observable.Start(() => { ++count; }, ImmediateScheduler.Instance));
Assert.Equal(0, count);
sut
.Initialize()
.Subscribe()
.Dispose();
Assert.Equal(1, count);
sut
.Initialize()
.Subscribe()
.Dispose();
Assert.Equal(1, count);
}
