protected override async Task InvokeTestMethodAsync()

in src/Microsoft.VisualStudio.Extensibility.Testing.Xunit.Shared/Threading/InProcessIdeTestInvoker.cs [144:203]
56 lines of code
7 McCabe index (conditional complexity)

        protected override async Task<decimal> InvokeTestMethodAsync(object testClassInstance)
        {
            var oldSyncContext = SynchronizationContext.Current;

            try
            {
                var asyncSyncContext = new AsyncTestSyncContext(oldSyncContext);
                SynchronizationContext.SetSynchronizationContext(asyncSyncContext);

                await Aggregator.RunAsync(
                    () => Timer.AggregateAsync(
                        async () =>
                        {
                            var parameterCount = TestMethod.GetParameters().Length;
                            var valueCount = TestMethodArguments == null ? 0 : TestMethodArguments.Length;
                            if (parameterCount != valueCount)
                            {
                                Aggregator.Add(
                                    new InvalidOperationException(
                                        $"The test method expected {parameterCount} parameter value{(parameterCount == 1 ? string.Empty : "s")}, but {valueCount} parameter value{(valueCount == 1 ? string.Empty : "s")} {(valueCount == 1 ? "was" : "were")} provided."));
                            }
                            else
                            {
                                var result = CallTestMethod(testClassInstance);
                                var task = GetTaskFromResult(result);
                                if (task != null)
                                {
                                    if (task.Status == TaskStatus.Created)
                                    {
                                        throw new InvalidOperationException("Test method returned a non-started Task (tasks must be started before being returned)");
                                    }

                                    try
                                    {
                                        await task;
                                    }
                                    catch (Exception ex) when (DataCollectionService.LogAndPropagate(ex))
                                    {
                                        throw ExceptionUtilities.Unreachable;
                                    }
                                }
                                else
                                {
                                    var ex = await asyncSyncContext.WaitForCompletionAsync();
                                    if (ex != null)
                                    {
                                        DataCollectionService.TryLog(ex);
                                        Aggregator.Add(ex);
                                    }
                                }
                            }
                        }));
            }
            finally
            {
                SynchronizationContext.SetSynchronizationContext(oldSyncContext);
            }

            return Timer.Total;
        }