public async Task GetDatasetAggregationsForSpecificationId_WhenSpeficationIdIsEmpty_ShouldThrowException()
        {
            // Arrange
            IDatasetsApiClient            datasetsApiClient             = Substitute.For <IDatasetsApiClient>();
            IMapper                       mapper                        = CreateMapper();
            DatasetAggregationsRepository datasetAggregationsRepository = new DatasetAggregationsRepository(datasetsApiClient, CreateMapper());
            ArgumentNullException         exception                     = null;

            // Act
            try
            {
                IEnumerable <DatasetAggregation> configuredTaskAwaiter = await datasetAggregationsRepository.GetDatasetAggregationsForSpecificationId(string.Empty);
            }
            catch (Exception e)
            {
                exception = e as ArgumentNullException;
            }

            // Assert
            exception.Should().NotBeNull();
            exception.Should().BeOfType <ArgumentNullException>();
            await datasetsApiClient.DidNotReceive().GetDatasetAggregationsBySpecificationId(Arg.Any <string>());
        }