public void MethodReturnsATaskOfTAndMutatesGlobalState()
{
const int expected = 5;
SyncMethods.MutateGlobalState();
Assert.AreEqual(expected, MutableGlobalState.State);
}
public void UsingAResultLooksFineWithTaskCompletionSource()
{
// what is the problem with this (only relevant with certain sync contexts)
const string expected = "foo";
var actual = SyncMethods
.WaitASecondAndReturnAValueUsingTaskCompletionSource(expected)
.Result;
Assert.AreEqual(expected, actual);
}
public void UsingResultLooksFineSoWhatsTheProblem()
{
// what is the problem with this (only relevant with certain sync contexts)
const string expected = "foo";
var actual = SyncMethods
.WaitASecondAndReturnAValue(expected)
.Result;
Assert.AreEqual(expected, actual);
}
public void SyncExceptionHandlingWithoutAwait()
{
Exception exceptionThrown = null;
try
{
SyncMethods.ThrowAnExceptionAfterOneSecond(1);
}
catch (Exception ex)
{
exceptionThrown = ex;
}
Assert.IsNotNull(exceptionThrown);
}
public void AwaitedAsyncWrappedInNonAwaitedAction()
{
Exception exceptionThrown = null;
Action willThrow = async() => await SyncMethods.ThrowAnExceptionAfterOneSecond(1);
try
{
willThrow();
}
catch (Exception ex)
{
exceptionThrown = ex;
}
Assert.IsNotNull(exceptionThrown);
}
public async Task SyncExceptionHandlingWithAwait()
{
Exception exceptionThrown = null;
try
{
await SyncMethods.ThrowAnExceptionAfterOneSecond(1);
}
catch (Exception ex)
{
exceptionThrown = ex;
}
Assert.IsNotNull(exceptionThrown);
Assert.IsInstanceOf <AggregateException>(exceptionThrown);
}
public async Task AwaitedAsyncWrappedInNonAwaitedFuncOfTask()
{
Exception exceptionThrown = null;
Func <Task> willThrow = async() => await SyncMethods.ThrowAnExceptionAfterOneSecond(1);
try
{
//awaitable because it's a func
await willThrow();
}
catch (Exception ex)
{
exceptionThrown = ex;
}
Assert.IsNotNull(exceptionThrown);
}
public async Task FindingMyException()
{
Exception exceptionThrown = null;
var delay = Task.Delay(TimeSpan.FromSeconds(0.5));
var errorProneTask = SyncMethods
.ThrowAnExceptionAfterOneSecond(1)
.ContinueWith(task => exceptionThrown = task.Exception);
var firstTaskToComplete = await Task.WhenAny(delay, errorProneTask);
Assert.AreEqual(delay, firstTaskToComplete);
//give the error prone task a chance to fail.
await Task.Delay(1);
Assert.IsNotNull(exceptionThrown);
}
public async Task LosingMyException()
{
Exception exceptionThrown = null;
var delay = Task.Delay(TimeSpan.FromSeconds(0.5));
var errorProneTask = SyncMethods.ThrowAnExceptionAfterOneSecond(1);
try
{
var firstTaskToComplete = await Task.WhenAny(delay, errorProneTask);
Assert.AreEqual(delay, firstTaskToComplete);
//give the error prone task a chance to fail.
await Task.Delay(1);
}
catch (Exception ex)
{
exceptionThrown = ex;
}
Assert.IsNotNull(exceptionThrown, "Exception wont be set because my code "
+ "on the calling thread left the try catch block");
}
