Extension for Moq that allow to easily mock async methods
var mock = new Mock<IFoo>();
// Setup of async function is as simple as doing it for standard function
mock.SetupAsync(x => x.ExecFuncAsync(It.IsAny<string>())).Returns<string>(s => "hello " + s);
// In particular compared to the syntax provided by Moq
mock.Setup(x => x.ExecFuncAsync(It.IsAny<string>())).ReturnsAsync<string, IFoo, object>(s => "hello " + s);
// And we also provide support of async actions (task without return value), which are missing in Moq
mock.SetupAsync(x => x.DoActionAsync());
// With the possibility to add callback on them
mock.SetupAsync(x => x.DoActionAsync(It.IsAny<string>())).Callback<string>(s => { });
// But if you stick to the Setup syntax instead of the SetupAsync you can also use our new CallbackAsync extension
mock.Setup(x => x.DoActionAsync(It.IsAny<string>())).CallbackAsync<string, IFoo>(s => {});This work has been inspired in the first place by a discussion on stackoverflow: https://stackoverflow.com/questions/21253523/setup-async-task-callback-in-moq-framework
Then our decision has been validated when we read that there is an opened issue that seems frozen unfortunately: devlooped/moq#384