public void Put_WithMockedModel_ShouldBeCalledOnce() { // Arrange var actualId = 4399; var dummyString = Guid.NewGuid().ToString().Replace("-", ""); var mockRepository = new Mock <IEntryRepository>(); var dbModel = new EntryModel() { CategoryId = 4400, SubCategoryId = 4401, LexiconFunction = dummyString, Recommendation = "delectus", Notes = "voluptatibus", }; mockRepository .Setup(m => m.Update(dbModel)); var controller = new EntryController(mockRepository.Object); // Act controller.Put(actualId, dbModel); // Assert mockRepository .Verify(m => m.Update( It.Is <EntryModel>( i => i.Id == actualId && i.LexiconFunction == dummyString)), Times.Once()); }