public void AddModel_HappyPath() { var makeName = "make3"; var make = _makeManager.AddMake(makeName); Assert.Equal(makeName, make.Name); var modelName = "model3"; var model = _modelManager.AddModel(make.Id, modelName); Assert.Equal(modelName, model.Name); var models = _modelManager.GetModelsByMakeId(make.Id); Assert.Contains(models, x => x.Name == modelName); }