public async Task CalculateDiff_success()
{
//Arrange
Guid fakeGuid = new Guid();
DiffRequestViewModel fakeData = new DiffRequestViewModel()
{
Id = fakeGuid
};
DiffViewModel fakeViewModel = GetDiffViewModelFake(fakeGuid);
_diffAppServiceMock.Setup(x => x.CalculateDiff(It.IsAny <Guid>()))
.Returns(Task.FromResult(fakeViewModel));
//Act
var diffController = new DiffController(_diffAppServiceMock.Object);
diffController.ControllerContext.HttpContext = _contextMock.Object;
var actionResult = await diffController.CalculateDiff(fakeData);
//Assert
Assert.Equal((actionResult as OkObjectResult).StatusCode, (int)System.Net.HttpStatusCode.OK);
Assert.Equal((((ObjectResult)actionResult).Value as DiffViewModel).Id, fakeGuid);
}