public async Task DtoReturned_PutRightFile_Created()
        {
            // Arrange
            const int id = 1;
            var       mockDiffService     = new Mock <IDiffService>();
            var       mockRetrieveService = new Mock <IRetrieveService>();
            var       mockUploadService   = new Mock <IUploadService>();
            var       leftFile            = Convert.FromBase64String(TestConstants.File1Base64Content);
            var       rightFile           = Convert.FromBase64String(TestConstants.File1Base64Content);

            mockUploadService.Setup(u => u.UploadLeftAsync(id, leftFile))
            .Returns(Task.FromResult(new FileComparisonDTO()
            {
                Id    = id,
                Left  = leftFile,
                Right = rightFile
            }));
            var controller = new FileDiffController(mockDiffService.Object, mockRetrieveService.Object, mockUploadService.Object);

            // Act
            var result = await controller.PutRightFileAsync(id, new FileContentDTO()
            {
                Data = TestConstants.File1Base64Content
            });

            // Assert
            Assert.IsNotNull(result, "The action result should not be null!");
            Assert.IsInstanceOfType(result, typeof(CreatedFileActionResult), "The action result should be 201-Created!");
        }
        public async Task EmptyFile_PutRightFile_BadRequest()
        {
            // Arrange
            const int id = 1;
            var       mockDiffService     = new Mock <IDiffService>();
            var       mockRetrieveService = new Mock <IRetrieveService>();
            var       mockUploadService   = new Mock <IUploadService>();
            var       rightFile           = new FileContentDTO()
            {
                Data = string.Empty
            };

            var controller = new FileDiffController(mockDiffService.Object, mockRetrieveService.Object, mockUploadService.Object);

            // Act
            var result = await controller.PutRightFileAsync(id, rightFile);

            // Assert
            Assert.IsNotNull(result, "The action result should not be null!");
            Assert.IsInstanceOfType(result, typeof(BadRequestResult), "The action result should be 400-BadRequest!");
        }