public void EditIncident()
        {
            // Arrange.
            var testData   = GetTestData();
            var testEntity = new Incident
            {
                Id       = 4,
                ClientId = 1,
                Theme    = "Жалоба",
                Date     = DateTime.Now
            };

            var mockDbSet = new Mock <DbSet <Incident> >();

            mockDbSet
            .As <IQueryable <Incident> >()
            .Setup(m => m.GetEnumerator())
            .Returns(testData.AsQueryable().GetEnumerator());

            var mockDbContext = new Mock <BankDbContext>();

            mockDbContext
            .Setup(m => m.Incidents)
            .Returns(mockDbSet.Object);
            mockDbContext
            .Setup(m => m.Entry(It.IsAny <Incident>()))
            .Callback(() =>
            {
                testData.ForEach(e =>
                {
                    if (e.Id == testEntity.Id)
                    {
                        e.ClientId = testEntity.ClientId;
                        e.Date     = testEntity.Date;
                        e.Text     = testEntity.Text;
                        e.Theme    = testEntity.Theme;
                    }
                });
            });

            var incidentsController = new IncidentsController(mockDbContext.Object);

            // Act.
            var actionResult = incidentsController.EditIncident(testEntity.Id, testEntity) as OkResult;
            var actEntity    = testData.Find(e => e.Id == testEntity.Id);

            // Assert.
            Assert.IsNotNull(actionResult);
            Assert.IsInstanceOfType(actionResult, typeof(OkResult));
            Assert.AreEqual(testEntity.Id, actEntity.Id);
            Assert.AreEqual(testEntity.ClientId, actEntity.ClientId);
            Assert.AreEqual(testEntity.Date, actEntity.Date);
            Assert.AreEqual(testEntity.Text, actEntity.Text);
            Assert.AreEqual(testEntity.Theme, actEntity.Theme);
        }