Add Unit test

Author: dellis1972

src/Xamarin.Android.Build.Tasks/Tasks/GenerateJavaStubs.cs

@@ -282,15 +282,15 @@ void Run (DirectoryAssemblyResolver res, bool useMarshalMethods)
 					TypeDefinition conflict;
 					bool hasConflict = false;
 					if (managed.TryGetValue (managedKey, out conflict)) {
-						if (!conflict.Module.Mvid.Equals(type.Module.Mvid)) {
+						if (!conflict.Module.Name.Equals(type.Module.Name)) {
 							if (!managedConflicts.TryGetValue (managedKey, out var list))
 								managedConflicts.Add (managedKey, list = new List<string> { conflict.GetPartialAssemblyName (cache) });
 							list.Add (type.GetPartialAssemblyName (cache));
 						}
 						hasConflict = true;
 					}
 					if (java.TryGetValue (javaKey, out conflict)) {
-						if (!conflict.Module.Mvid.Equals(type.Module.Mvid)) {
+						if (!conflict.Module.Name.Equals(type.Module.Name)) {
 							if (!javaConflicts.TryGetValue (javaKey, out var list))
 								javaConflicts.Add (javaKey, list = new List<string> { conflict.GetAssemblyQualifiedName (cache) });
 							list.Add (type.GetAssemblyQualifiedName (cache));

src/Xamarin.Android.Build.Tasks/Tests/Xamarin.Android.Build.Tests/Tasks/LinkerTests.cs

@@ -509,5 +509,41 @@ public void AndroidUseNegotiateAuthentication ([Values (true, false, null)] bool
 				}
 			}
 		}
+
+		[Test]
+		public void DoNotErrorOnPerArchJavaTypeDuplicates ()
+		{
+			if (!Builder.UseDotNet)
+				Assert.Ignore ("Test only valid on .NET");
+
+			var path = Path.Combine (Root, "temp", TestName);
+			var lib = new XamarinAndroidLibraryProject { IsRelease = true, ProjectName = "Lib1" };
+			lib.SetProperty ("IsTrimmable", "true");
+			lib.Sources.Add (new BuildItem.Source ("Library1.cs") {
+				TextContent = () => @"
+namespace Lib1;
+public class Library1 : Java.Lang.Object {
+	private static bool Is64Bits = IntPtr.Size >= 8;
+
+	public static bool Is64 () {
+		return Is64Bits;
+	}
+}",
+			});
+			var proj = new XamarinAndroidApplicationProject { IsRelease = true, ProjectName = "App1" };
+			proj.References.Add(new BuildItem.ProjectReference (Path.Combine ("..", "Lib1", "Lib1.csproj"), "Lib1"));
+			proj.MainActivity = proj.DefaultMainActivity.Replace (
+				"base.OnCreate (bundle);",
+				"base.OnCreate (bundle);\n" +
+				"if (Lib1.Library1.Is64 ()) Console.WriteLine (\"Hello World!\");");
+
+
+			using (var lb = CreateDllBuilder (Path.Combine (path, "Lib1"))) {
+				using (var b = CreateApkBuilder (Path.Combine (path, "App1"))) {
+					Assert.IsTrue (lb.Build (lib), "build should have succeeded.");
+					Assert.IsTrue (b.Build (proj), "build should have succeeded.");
+				}
+			}
+		}
 	}
 }