protected override void Arrange() { base.Arrange(); var locator = new Mock <ConfigurationSectionLocator>(); locator.Setup(x => x.ConfigurationSectionNames).Returns(new[] { "testSection" }); Container.RegisterInstance(locator.Object); var section = new ElementForValidation(); var source = new DesignDictionaryConfigurationSource(); source.Add("testSection", section); SourceModel = Container.Resolve <ConfigurationSourceModel>(); SourceModel.Load(source); Section = SourceModel.Sections.Where(s => s.SectionName == "testSection").Single(); }