public void GetContractorsByStreet()
        {
            Mock<IContractorRepository> mock = new Mock<IContractorRepository>();
            mock.Setup(a => a.Contractors).Returns(new Contractor[]
            {
                new Contractor { id = 1, street = "Spławy 2a" },
                new Contractor { id = 2, street = "Wrocławska 8" },
                new Contractor { id = 3, street = "Spławy 2a" },
                new Contractor { id = 4, street = "Karmelicka 9"},
                new Contractor { id = 5, street = "Jana Pawła 16" },
                new Contractor { id = 6, street = "Spławy 2a" }
            }.AsQueryable());

            ContractorController ctrl = new ContractorController(mock.Object);
            object [] temp = ctrl.GetContractorsByStreet("Spławy 2a");
            Assert.AreEqual(temp.Length, 3);
            Assert.AreEqual(((Contractor)temp[2]).id, 6);

            temp = ctrl.GetContractorsByStreet("Karmelicka 9");
            Assert.AreEqual(temp.Length, 1);
            Assert.AreEqual(((Contractor)temp[0]).id, 4);

            temp = ctrl.GetContractorsByStreet("Warszawska 19");
            Assert.AreEqual(temp.Length, 0);
        }