FetchLoanDetailTestCase2.dart

test(
      "Use case must also fail when fetch loan fails from network",
          () {
        FetchLoanDetail fetchLoanUseCase =
        FetchLoanDetail(MockedFailedRateFetchRepository(RateFetchFailType.NETWORK));

        fetchLoanUseCase.execute(LoanParamRequest(100, 2), (data) {

        }, expectAsync1((error) {
          expect(error, isNot(isInstanceOf<RateFetchFailException>()),
              reason: "Usecase didn't fail with RateFetchException on network failure");
        }));
      });