Add DebuggerDisableUserUnhandledExceptionsAttribute

src/coreclr/nativeaot/System.Private.CoreLib/src/System/Diagnostics/Debugger.cs

@@ -5,7 +5,7 @@
 
 namespace System.Diagnostics
 {
-    public static class Debugger
+    public static partial class Debugger
     {
         [MethodImpl(MethodImplOptions.NoInlining)]
         [DebuggerHidden] // this helps VS appear to stop on the source line calling Debugger.Break() instead of inside it

src/libraries/System.Private.CoreLib/src/System.Private.CoreLib.Shared.projitems

@@ -290,7 +290,9 @@
     <Compile Include="$(MSBuildThisFileDirectory)System\Diagnostics\Contracts\Contracts.cs" />
     <Compile Include="$(MSBuildThisFileDirectory)System\Diagnostics\Debug.cs" />
     <Compile Include="$(MSBuildThisFileDirectory)System\Diagnostics\DebuggableAttribute.cs" />
+    <Compile Include="$(MSBuildThisFileDirectory)System\Diagnostics\Debugger.cs" />
     <Compile Include="$(MSBuildThisFileDirectory)System\Diagnostics\DebuggerBrowsableAttribute.cs" />
+    <Compile Include="$(MSBuildThisFileDirectory)System\Diagnostics\DebuggerDisableUserUnhandledExceptionsAttribute.cs" />
     <Compile Include="$(MSBuildThisFileDirectory)System\Diagnostics\DebuggerDisplayAttribute.cs" />
     <Compile Include="$(MSBuildThisFileDirectory)System\Diagnostics\DebuggerHiddenAttribute.cs" />
     <Compile Include="$(MSBuildThisFileDirectory)System\Diagnostics\DebuggerNonUserCodeAttribute.cs" />
@@ -2799,4 +2801,4 @@
     <Compile Include="$(MSBuildThisFileDirectory)System\Numerics\IUnaryPlusOperators.cs" />
     <Compile Include="$(MSBuildThisFileDirectory)System\Numerics\IUnsignedNumber.cs" />
   </ItemGroup>
-</Project>
+</Project>

src/libraries/System.Private.CoreLib/src/System/Diagnostics/Debugger.cs

@@ -0,0 +1,21 @@
+// Licensed to the .NET Foundation under one or more agreements.
+// The .NET Foundation licenses this file to you under the MIT license.
+
+using System.Runtime.CompilerServices;
+
+namespace System.Diagnostics
+{
+    public static partial class Debugger
+    {
+        /// <summary>
+        /// Signals a breakpoint to an attached debugger with the <paramref name="exception"/> details
+        /// if a .NET debugger is attached with break on user-unhandled exception enabled and a method
+        /// attributed with DebuggerDisableUserUnhandledExceptionsAttribute calls this method.
+        /// </summary>
+        /// <param name="exception">The user-unhandled exception.</param>
+        [MethodImpl(MethodImplOptions.NoInlining | MethodImplOptions.NoOptimization)]
+        public static void BreakForUserUnhandledException(Exception exception)
+        {
+        }
+    }
+}

src/libraries/System.Private.CoreLib/src/System/Diagnostics/DebuggerDisableUserUnhandledExceptionsAttribute.cs

@@ -0,0 +1,15 @@
+// Licensed to the .NET Foundation under one or more agreements.
+// The .NET Foundation licenses this file to you under the MIT license.
+
+namespace System.Diagnostics
+{
+    /// <summary>
+    /// If a .NET Debugger is attached which supports the Debugger.BreakForUserUnhandledException(Exception) API,
+    /// this attribute will prevent the debugger from breaking on user-unhandled exceptions when the
+    /// exception is caught by a method with this attribute, unless BreakForUserUnhandledException is called.
+    /// </summary>
+    [AttributeUsage(AttributeTargets.Method)]
+    public sealed class DebuggerDisableUserUnhandledExceptionsAttribute : Attribute
+    {
+    }
+}

src/libraries/System.Runtime/ref/System.Runtime.cs

@@ -8666,6 +8666,7 @@ public static partial class Debugger
         public static readonly string? DefaultCategory;
         public static bool IsAttached { get { throw null; } }
         public static void Break() { }
+        public static void BreakForUserUnhandledException(System.Exception exception) { }
         public static bool IsLogging() { throw null; }
         public static bool Launch() { throw null; }
         public static void Log(int level, string? category, string? message) { }
@@ -8683,6 +8684,11 @@ public enum DebuggerBrowsableState
         Collapsed = 2,
         RootHidden = 3,
     }
+    [System.AttributeUsage(System.AttributeTargets.Method)]
+    public sealed class DebuggerDisableUserUnhandledExceptionsAttribute : System.Attribute
+    {
+        public DebuggerDisableUserUnhandledExceptionsAttribute() { }
+    }
     [System.AttributeUsageAttribute(System.AttributeTargets.Assembly | System.AttributeTargets.Class | System.AttributeTargets.Delegate | System.AttributeTargets.Enum | System.AttributeTargets.Field | System.AttributeTargets.Property | System.AttributeTargets.Struct, AllowMultiple=true)]
     public sealed partial class DebuggerDisplayAttribute : System.Attribute
     {

src/mono/System.Private.CoreLib/src/System/Diagnostics/Debugger.cs

@@ -5,7 +5,7 @@
 
 namespace System.Diagnostics
 {
-    public static class Debugger
+    public static partial class Debugger
     {
         public static readonly string? DefaultCategory;