From a4301a0466b575d184ec9dea4988a1f49edbf18c Mon Sep 17 00:00:00 2001
From: Theodore Tsirpanis <teo@tsirpanis.gr>
Date: Sat, 30 Dec 2023 16:54:45 +0200
Subject: [PATCH 1/3] [mono] Do not throw in
 AssemblyExtensions.TryGetRawMetadata.

---
 .../src/System/Reflection/Metadata/AssemblyExtensions.cs | 9 ++++++++-
 1 file changed, 8 insertions(+), 1 deletion(-)

diff --git a/src/mono/System.Private.CoreLib/src/System/Reflection/Metadata/AssemblyExtensions.cs b/src/mono/System.Private.CoreLib/src/System/Reflection/Metadata/AssemblyExtensions.cs
index 9c677baa4bda0a..7eafc1a560964e 100644
--- a/src/mono/System.Private.CoreLib/src/System/Reflection/Metadata/AssemblyExtensions.cs
+++ b/src/mono/System.Private.CoreLib/src/System/Reflection/Metadata/AssemblyExtensions.cs
@@ -8,6 +8,13 @@ namespace System.Reflection.Metadata
     public static class AssemblyExtensions
     {
         [CLSCompliant(false)]
-        public static unsafe bool TryGetRawMetadata(this Assembly assembly, out byte* blob, out int length) => throw new NotImplementedException();
+        public static unsafe bool TryGetRawMetadata(this Assembly assembly, out byte* blob, out int length)
+        {
+            ArgumentNullException.ThrowIfNull(assembly);
+
+            blob = null;
+            length = 0;
+            return false;
+        }
     }
 }

From e243bdc67d60ecf8db9773900a85bb8f5992062b Mon Sep 17 00:00:00 2001
From: Theodore Tsirpanis <teo@tsirpanis.gr>
Date: Sun, 11 Feb 2024 19:59:45 +0200
Subject: [PATCH 2/3] Add a test for `AssemblyExtensions.TryGetRawMetadata`.

---
 .../tests/AssemblyExtensionsTest.cs           | 25 +++++++++++++++++++
 .../tests/System.Runtime.Loader.Tests.csproj  |  2 ++
 2 files changed, 27 insertions(+)
 create mode 100644 src/libraries/System.Runtime.Loader/tests/AssemblyExtensionsTest.cs

diff --git a/src/libraries/System.Runtime.Loader/tests/AssemblyExtensionsTest.cs b/src/libraries/System.Runtime.Loader/tests/AssemblyExtensionsTest.cs
new file mode 100644
index 00000000000000..0fde8bea7de7f4
--- /dev/null
+++ b/src/libraries/System.Runtime.Loader/tests/AssemblyExtensionsTest.cs
@@ -0,0 +1,25 @@
+// Licensed to the .NET Foundation under one or more agreements.
+// The .NET Foundation licenses this file to you under the MIT license.
+
+using Xunit;
+using System.Reflection.Metadata;
+using System.Reflection;
+
+namespace System.Runtime.Loader.Tests
+{
+    public unsafe class AssemblyExtensionsTest
+    {
+        [Fact]
+        public void TryGetRawMetadata()
+        {
+            bool supportsRawMetadata = PlatformDetection.IsNotMonoRuntime && PlatformDetection.IsNotNativeAot;
+
+            Assembly assembly = typeof(AssemblyExtensionsTest).Assembly;
+            bool hasMetadata = assembly.TryGetRawMetadata(out byte* blob, out int length);
+
+            Assert.Equal(supportsRawMetadata, hasMetadata);
+            Assert.Equal(supportsRawMetadata, blob != null);
+            Assert.Equal(supportsRawMetadata, length > 0);
+        }
+    }
+}
diff --git a/src/libraries/System.Runtime.Loader/tests/System.Runtime.Loader.Tests.csproj b/src/libraries/System.Runtime.Loader/tests/System.Runtime.Loader.Tests.csproj
index 03138144a9db7b..d047aa0b74dc72 100644
--- a/src/libraries/System.Runtime.Loader/tests/System.Runtime.Loader.Tests.csproj
+++ b/src/libraries/System.Runtime.Loader/tests/System.Runtime.Loader.Tests.csproj
@@ -2,6 +2,7 @@
   <PropertyGroup>
     <RootNamespace>System.Runtime.Loader.Tests</RootNamespace>
     <TargetFramework>$(NetCoreAppCurrent)</TargetFramework>
+    <AllowUnsafeBlocks>true</AllowUnsafeBlocks>
     <TestRuntime>true</TestRuntime>
     <IncludeRemoteExecutor>true</IncludeRemoteExecutor>
     <!-- Some tests rely on no deps.json file being present. -->
@@ -16,6 +17,7 @@
   <ItemGroup>
     <Compile Include="ApplyUpdateTest.cs" />
     <Compile Include="ApplyUpdateUtil.cs" />
+    <Compile Include="AssemblyExtensionsTest.cs" />
     <Compile Include="AssemblyLoadContextTest.cs" />
     <Compile Include="CollectibleAssemblyLoadContextTest.cs" />
     <Compile Include="ContextualReflection.cs" />

From a990b2364d5918c7a447198fca5d5a67437e2580 Mon Sep 17 00:00:00 2001
From: Theodore Tsirpanis <teo@tsirpanis.gr>
Date: Sat, 17 Feb 2024 15:13:21 +0200
Subject: [PATCH 3/3] Try to read the assembly metadata blob in the test.

---
 .../System.Runtime.Loader/tests/AssemblyExtensionsTest.cs  | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/src/libraries/System.Runtime.Loader/tests/AssemblyExtensionsTest.cs b/src/libraries/System.Runtime.Loader/tests/AssemblyExtensionsTest.cs
index 0fde8bea7de7f4..71a4cb434583d1 100644
--- a/src/libraries/System.Runtime.Loader/tests/AssemblyExtensionsTest.cs
+++ b/src/libraries/System.Runtime.Loader/tests/AssemblyExtensionsTest.cs
@@ -20,6 +20,13 @@ public void TryGetRawMetadata()
             Assert.Equal(supportsRawMetadata, hasMetadata);
             Assert.Equal(supportsRawMetadata, blob != null);
             Assert.Equal(supportsRawMetadata, length > 0);
+
+            if (supportsRawMetadata)
+            {
+                var metadataReader = new MetadataReader(blob, length);
+                string assemblyName = metadataReader.GetString(metadataReader.GetAssemblyDefinition().Name);
+                Assert.Equal(assembly.GetName().Name, assemblyName);
+            }
         }
     }
 }