public When_EmployerService_Is_Called_To_Get_Opportunity_Employer() { var employerRepository = Substitute.For <IRepository <Domain.Models.Employer> >(); _opportunityRepository = Substitute.For <IOpportunityRepository>(); _opportunityRepository.GetSingleOrDefaultAsync(Arg.Any <Expression <Func <Domain.Models.Opportunity, bool> > >(), Arg.Any <Expression <Func <Domain.Models.Opportunity, FindEmployerViewModel> > >()) .Returns(new FindEmployerViewModelBuilder().BuildWithEmployer()); var employerService = new EmployerService(employerRepository, _opportunityRepository, Substitute.For <IMapper>(), Substitute.For <IValidator <CrmEmployerEventBase> >(), Substitute.For <IMessageQueueService>()); _result = employerService.GetOpportunityEmployerAsync(1, 2).GetAwaiter().GetResult(); }