add test case for classes with identical names

InterfaceGenerator.Tests/SameName/SameNameClass.1.cs

@@ -0,0 +1,12 @@
+// ReSharper disable CheckNamespace
+namespace InterfaceGenerator.Tests.SameName_1;
+
+/// <summary>
+/// A class with the same name as <see cref="SameName_2.SameNameClass"/>. It exists to test if the generated source units have fully
+/// qualified names.
+/// </summary>
+[GenerateAutoInterface]
+internal class SameNameClass : ISameNameClass
+{
+    
+}

InterfaceGenerator.Tests/SameName/SameNameClass.2.cs

@@ -0,0 +1,8 @@
+// ReSharper disable CheckNamespace
+namespace InterfaceGenerator.Tests.SameName_2;
+
+[GenerateAutoInterface]
+internal class SameNameClass : ISameNameClass
+{
+    
+}