public void FindTypesByAttributeInstance() { var assemblyName = "test1.dll"; GenerateAssembly(@"namespace ClassLibrary { [System.Obsolete] public class ClassWithAttribute { public int GetNumber() { return 42; } } }", assemblyName); Assert.IsTrue(File.Exists(assemblyName)); var types = new ObsoleteAttribute().FindAttributedTypes(".", assemblyName); Assert.AreEqual(1, types.Count()); }