Address review findings and cleanup

- Replace try-finally cleanup with IDisposable temp directories
- Add IGCUserPeer infrastructure methods (monodroidAddReference,
  monodroidClearReferences, refList) to JCW Java source generator
- Port improved UCO attribute and NegativeEdgeCase tests from #10831

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

Author: simonrozsival

src/Microsoft.Android.Sdk.TrimmableTypeMap/Generator/JcwJavaSourceGenerator.cs

@@ -86,6 +86,7 @@ internal void Generate (JavaPeerInfo type, TextWriter writer)
 		WriteStaticInitializer (type, writer);
 		WriteConstructors (type, writer);
 		WriteMethods (type, writer);
+		WriteGCUserPeerMethods (writer);
 		WriteClassClose (writer);
 	}
 
@@ -222,6 +223,27 @@ static void WriteMethods (JavaPeerInfo type, TextWriter writer)
 		}
 	}
 
+	static void WriteGCUserPeerMethods (TextWriter writer)
+	{
+		writer.Write ("""
+
+	private java.util.ArrayList refList;
+	public void monodroidAddReference (java.lang.Object obj)
+	{
+		if (refList == null)
+			refList = new java.util.ArrayList ();
+		refList.add (obj);
+	}
+
+	public void monodroidClearReferences ()
+	{
+		if (refList != null)
+			refList.clear ();
+	}
+
+""");
+	}
+
 	static void WriteClassClose (TextWriter writer)
 	{
 		writer.WriteLine ('}');

tests/Microsoft.Android.Sdk.TrimmableTypeMap.Tests/Generator/FixtureTestBase.cs

@@ -33,10 +33,16 @@ protected static JavaPeerInfo FindFixtureByJavaName (string javaName)
 		return peer;
 	}
 
-	protected static void CleanUpDir (string path)
+	protected static string CreateTempDir ()
 	{
-		var dir = Path.GetDirectoryName (path);
-		if (dir != null && Directory.Exists (dir))
+		var dir = Path.Combine (Path.GetTempPath (), $"typemap-test-{Guid.NewGuid ():N}");
+		Directory.CreateDirectory (dir);
+		return dir;
+	}
+
+	protected static void DeleteTempDir (string dir)
+	{
+		if (Directory.Exists (dir))
 			try { Directory.Delete (dir, true); } catch { }
 	}
 

tests/Microsoft.Android.Sdk.TrimmableTypeMap.Tests/Generator/JcwJavaSourceGeneratorTests.cs

@@ -62,25 +62,20 @@ public void JniTypeToJava_ConvertsCorrectly (string jniType, string expected)
 
 	}
 
-	public class Filtering
+	public class Filtering : IDisposable
 	{
+		readonly string _outputDir = CreateTempDir ();
+		public void Dispose () => DeleteTempDir (_outputDir);
 
 		[Fact]
 		public void Generate_SkipsMcwTypes ()
 		{
 			var peers = ScanFixtures ();
 			var generator = new JcwJavaSourceGenerator ();
-			var outputDir = Path.Combine (Path.GetTempPath (), $"jcw-test-{Guid.NewGuid ():N}");
-			try {
-				var files = generator.Generate (peers, outputDir);
-				Assert.DoesNotContain (files, f => f.EndsWith ("java/lang/Object.java"));
-				Assert.DoesNotContain (files, f => f.EndsWith ("android/app/Activity.java"));
-				Assert.Contains (files, f => f.Replace ('\\', '/').Contains ("my/app/MainActivity.java"));
-			} finally {
-				if (Directory.Exists (outputDir)) {
-					Directory.Delete (outputDir, true);
-				}
-			}
+			var files = generator.Generate (peers, _outputDir);
+			Assert.DoesNotContain (files, f => f.EndsWith ("java/lang/Object.java"));
+			Assert.DoesNotContain (files, f => f.EndsWith ("android/app/Activity.java"));
+			Assert.Contains (files, f => f.Replace ('\\', '/').Contains ("my/app/MainActivity.java"));
 		}
 
 	}
@@ -97,6 +92,15 @@ public void Generate_MainActivity_HasClassDeclaration ()
 			Assert.Contains ("\t\tmono.android.IGCUserPeer\n", java);
 		}
 
+		[Fact]
+		public void Generate_MainActivity_HasIGCUserPeerMethods ()
+		{
+			var java = GenerateFixture ("my/app/MainActivity");
+			Assert.Contains ("private java.util.ArrayList refList;", java);
+			Assert.Contains ("public void monodroidAddReference (java.lang.Object obj)", java);
+			Assert.Contains ("public void monodroidClearReferences ()", java);
+		}
+
 		[Fact]
 		public void Generate_AbstractType_HasAbstractModifier ()
 		{
@@ -247,28 +251,23 @@ public void Generate_NestedType_HasCorrectPackageAndClassName ()
 
 	}
 
-	public class OutputFilePath
+	public class OutputFilePath : IDisposable
 	{
+		readonly string _outputDir = CreateTempDir ();
+		public void Dispose () => DeleteTempDir (_outputDir);
 
 		[Fact]
 		public void Generate_CreatesCorrectFileStructure ()
 		{
 			var peers = ScanFixtures ();
 			var generator = new JcwJavaSourceGenerator ();
-			var outputDir = Path.Combine (Path.GetTempPath (), $"jcw-test-{Guid.NewGuid ():N}");
-			try {
-				var files = generator.Generate (peers, outputDir);
-				Assert.NotEmpty (files);
-
-				foreach (var file in files) {
-					Assert.StartsWith (outputDir, file);
-					Assert.True (File.Exists (file), $"Generated file should exist: {file}");
-					Assert.EndsWith (".java", file);
-				}
-			} finally {
-				if (Directory.Exists (outputDir)) {
-					Directory.Delete (outputDir, true);
-				}
+			var files = generator.Generate (peers, _outputDir);
+			Assert.NotEmpty (files);
+
+			foreach (var file in files) {
+				Assert.StartsWith (_outputDir, file);
+				Assert.True (File.Exists (file), $"Generated file should exist: {file}");
+				Assert.EndsWith (".java", file);
 			}
 		}
 
@@ -287,8 +286,7 @@ public void Generate_InvalidJniName_Throws (string badJniName)
 		{
 			var peer = MakeAcwPeer (badJniName, "Test.Bad", "TestApp");
 			var generator = new JcwJavaSourceGenerator ();
-			var outputDir = Path.Combine (Path.GetTempPath (), $"jcw-test-{Guid.NewGuid ():N}");
-			Assert.Throws<ArgumentException> (() => generator.Generate (new [] { peer }, outputDir));
+			Assert.Throws<ArgumentException> (() => generator.Generate (new [] { peer }, _outputDir));
 		}
 
 		[Theory]
@@ -301,14 +299,7 @@ public void Generate_ValidJniName_DoesNotThrow (string validJniName)
 		{
 			var peer = MakeAcwPeer (validJniName, "Test.Valid", "TestApp");
 			var generator = new JcwJavaSourceGenerator ();
-			var outputDir = Path.Combine (Path.GetTempPath (), $"jcw-test-{Guid.NewGuid ():N}");
-			try {
-				generator.Generate (new [] { peer }, outputDir);
-			} finally {
-				if (Directory.Exists (outputDir)) {
-					Directory.Delete (outputDir, true);
-				}
-			}
+			generator.Generate (new [] { peer }, _outputDir);
 		}
 
 	}