public void StartDateSpecification(DateTime?startDate, bool expected)
        {
            ISpecification <Therapy> specification = new TherapyStartDateSpecification(startDate);
            bool result = specification.IsSatisfiedBy(_therapy);

            Assert.Equal(result, expected);
        }
        public static ISpecification <Therapy> ToTherapySpecification(this TherapySearchDTO parameters)
        {
            ISpecification <Therapy> filter = new TherapyStartDateSpecification(parameters.StartDate);

            filter = filter.BinaryOperation(
                parameters.EndDateOperator, new TherapyEndDateSpecification(parameters.EndDate));
            filter = filter.BinaryOperation(
                parameters.DoctorSurnameOperator, new TherapyDoctorSurnameSpecification(parameters.DoctorSurname));
            filter = filter.BinaryOperation(
                parameters.DrugNameOperator, new TherapyDrugNameSpacification(parameters.DrugName));

            return(filter);
        }