public void Contains_CreateDecoratorInstanceWithAllowedExtensionsAndInjectAdditionalExtensions_ContainsAdditionalExtensions() { // arrange AdditionalExtensionsDecorator additionalExtensions = new AdditionalExtensionsDecorator(); AllowedExtensionsDecorator allowedExtensions = new AllowedExtensionsDecorator(additionalExtensions); // act, assert foreach (string extension in additionalExtensions.AllowedExtensions) { Assert.IsTrue(allowedExtensions.Contains(extension)); } }