wip

Author: pavelsavara

src/mono/browser/runtime/runtime.c

@@ -197,6 +197,8 @@ init_icall_table (void)
 static void*
 get_native_to_interp (MonoMethod *method, void *extra_arg)
 {
+	assert (method);
+
 	void *addr = NULL;
 	MONO_ENTER_GC_UNSAFE;
 	MonoClass *klass = mono_method_get_class (method);

src/mono/mono/mini/interp/interp.c

@@ -3469,6 +3469,14 @@ interp_create_method_pointer (MonoMethod *method, gboolean compile, MonoError *e
 	if (method->wrapper_type == MONO_WRAPPER_NATIVE_TO_MANAGED) {
 		WrapperInfo *info = mono_marshal_get_wrapper_info (method);
 		MonoMethod *orig_method = info->d.native_to_managed.method;
+		if (!orig_method) {
+			char *s = mono_method_get_full_name (method);
+			char *msg = g_strdup_printf ("No native to managed transition for method '%s', missing [UnmanagedCallersOnly] attribute.", s);
+			mono_error_set_platform_not_supported (error, msg);
+			g_free (s);
+			g_free (msg);
+			return NULL;
+		}
 
 		/*
 		 * These are called from native code. Ask the host app for a trampoline.

src/mono/wasm/Wasm.Build.Tests/MiscTests.cs

@@ -0,0 +1,37 @@
+// Licensed to the .NET Foundation under one or more agreements.
+// The .NET Foundation licenses this file to you under the MIT license.
+
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Threading.Tasks;
+using System.Text.RegularExpressions;
+using Xunit.Abstractions;
+using Xunit;
+
+#nullable enable
+
+namespace Wasm.Build.Tests;
+
+public class MiscTests : WasmTemplateTestsBase
+{
+    public MiscTests(ITestOutputHelper output, SharedBuildPerTestClassFixture buildContext)
+        : base(output, buildContext)
+    {
+    }
+
+    [Fact]
+    public async Task TestGetFunctionPointerForDelegate()
+    {
+        Configuration config = Configuration.Release;
+        ProjectInfo info = CopyTestAsset(config, false, TestAsset.WasmBasicTestApp, "GetFunctionPointerForDelegate");
+
+        BuildProject(info, config, new BuildOptions(AssertAppBundle: false), isNativeBuild: false);
+
+        var result = await RunForBuildWithDotnetRun(new BrowserRunOptions(Configuration: config, TestScenario: "GetFunctionPointerForDelegate"));
+
+        Assert.Equal(2, result.TestOutput.Count);
+        Assert.Contains(result.TestOutput, m => m.Contains("System.PlatformNotSupportedException"));
+        Assert.Contains(result.TestOutput, m => m.Contains("No native to managed transition for method '(wrapper native-to-managed) void MiscTests/<>c:<TestGetFunctionPointerForDelegate>b__0_0 ()', missing [UnmanagedCallersOnly] attribute."));
+    }
+}

src/mono/wasm/testassets/WasmBasicTestApp/App/MiscTests.cs

@@ -0,0 +1,27 @@
+// Licensed to the .NET Foundation under one or more agreements.
+// The .NET Foundation licenses this file to you under the MIT license.
+
+using System;
+using System.Runtime.InteropServices;
+using System.Runtime.InteropServices.JavaScript;
+
+public partial class MiscTests
+{
+    [JSExport]
+    public static unsafe int TestGetFunctionPointerForDelegate()
+    {
+        try
+        {
+            nint fptr = Marshal.GetFunctionPointerForDelegate(new Action(() => Console.WriteLine("Managed method callee")));
+            ((delegate* unmanaged<void>)fptr)();
+            Console.WriteLine("No Exception");
+        }
+        catch (Exception ex)
+        {
+            Console.WriteLine("TestOutput -> " + ex.Message);
+            Console.WriteLine("TestOutput -> " + ex.GetType().FullName);
+        }
+
+        return 42;
+    }
+}

src/mono/wasm/testassets/WasmBasicTestApp/App/wwwroot/main.js

@@ -166,6 +166,8 @@ switch (testCase) {
     case "EnvVariablesTest":
         dotnet.withEnvironmentVariable("foo", "bar");
         break;
+    case "GetFunctionPointerForDelegate":
+        break;
     case "HttpNoStreamingTest":
         break;
     case "BrowserProfilerTest":
@@ -281,6 +283,18 @@ try {
 
             exit(retHttp == 42 ? 0 : 1);
             break;
+        case "GetFunctionPointerForDelegate":
+            console.log("not ready yet")
+            const miscExports = await getAssemblyExports(config.mainAssemblyName);
+            const testGetFunctionPointerForDelegate = miscExports.MiscTests.TestGetFunctionPointerForDelegate;
+            console.log("ready");
+
+            const retMics = testGetFunctionPointerForDelegate();
+            document.getElementById("out").innerHTML = retMics;
+            console.debug(`ret: ${retMics}`);
+
+            exit(retMics == 42 ? 0 : 1);
+            break;
         case "EnvVariablesTest":
             console.log("not ready yet")
             const myExportsEnv = await getAssemblyExports(config.mainAssemblyName);