diff --git a/csharp/test/Ice/adapterDeactivation/ServantLocatorI.cs b/csharp/test/Ice/adapterDeactivation/ServantLocatorI.cs
index 475af2a93c3..02d2749c475 100644
--- a/csharp/test/Ice/adapterDeactivation/ServantLocatorI.cs
+++ b/csharp/test/Ice/adapterDeactivation/ServantLocatorI.cs
@@ -36,13 +36,7 @@ public ServantLocatorI()
                 }
             }
 
-            private static void test(bool b)
-            {
-                if (!b)
-                {
-                    throw new System.Exception();
-                }
-            }
+            private static void test(bool b) => global::Test.TestHelper.test(b);
 
             public Ice.Object locate(Ice.Current current, out System.Object cookie)
             {
diff --git a/csharp/test/Ice/ami/TestI.cs b/csharp/test/Ice/ami/TestI.cs
index b49ded40948..d4edf7300bc 100644
--- a/csharp/test/Ice/ami/TestI.cs
+++ b/csharp/test/Ice/ami/TestI.cs
@@ -8,14 +8,7 @@ namespace ami
     {
         public class TestI : Test.TestIntfDisp_
         {
-            protected static void test(bool b)
-            {
-                if (!b)
-                {
-                    Debug.Assert(false);
-                    throw new System.Exception();
-                }
-            }
+            private static void test(bool b) => global::Test.TestHelper.test(b);
 
             public TestI()
             {
diff --git a/csharp/test/Ice/background/AllTests.cs b/csharp/test/Ice/background/AllTests.cs
index 7d09e3d57d6..624bdf4ab2e 100644
--- a/csharp/test/Ice/background/AllTests.cs
+++ b/csharp/test/Ice/background/AllTests.cs
@@ -2,7 +2,7 @@
 
 using Test;
 
-public class AllTests
+public class AllTests : global::Test.AllTests
 {
     public class Progress : IProgress<bool>
     {
@@ -20,14 +20,6 @@ public void Report(bool value)
         }
     }
 
-    private static void test(bool b)
-    {
-        if (!b)
-        {
-            throw new System.Exception();
-        }
-    }
-
     private class OpThread
     {
         internal OpThread(BackgroundPrx background)
diff --git a/csharp/test/Ice/dictMapping/Twoways.cs b/csharp/test/Ice/dictMapping/Twoways.cs
index 945e078f5e5..9f636a728fb 100644
--- a/csharp/test/Ice/dictMapping/Twoways.cs
+++ b/csharp/test/Ice/dictMapping/Twoways.cs
@@ -6,13 +6,7 @@ namespace dictMapping
     {
         internal class Twoways
         {
-            private static void test(bool b)
-            {
-                if (!b)
-                {
-                    throw new System.Exception();
-                }
-            }
+            private static void test(bool b) => global::Test.TestHelper.test(b);
 
             internal static void twoways(Ice.Communicator communicator, Test.MyClassPrx p)
             {
diff --git a/csharp/test/Ice/dictMapping/TwowaysAMI.cs b/csharp/test/Ice/dictMapping/TwowaysAMI.cs
index 60399e02b0e..d369e0b1540 100644
--- a/csharp/test/Ice/dictMapping/TwowaysAMI.cs
+++ b/csharp/test/Ice/dictMapping/TwowaysAMI.cs
@@ -1,26 +1,12 @@
 // Copyright (c) ZeroC, Inc.
 
-/* Unmerged change from project 'collocated'
-Before:
-using System.Diagnostics;
-using System.Collections.Generic;
-After:
-using System.Collections.Generic;
-using System.Diagnostics;
-*/
 namespace Ice
 {
     namespace dictMapping
     {
         public class TwowaysAMI
         {
-            private static void test(bool b)
-            {
-                if (!b)
-                {
-                    throw new System.SystemException();
-                }
-            }
+            private static void test(bool b) => global::Test.TestHelper.test(b);
 
             internal static async Task twowaysAMI(Test.MyClassPrx p)
             {
diff --git a/csharp/test/Ice/executor/Executor.cs b/csharp/test/Ice/executor/Executor.cs
index 9e3cd0aa49a..0a2477547b7 100644
--- a/csharp/test/Ice/executor/Executor.cs
+++ b/csharp/test/Ice/executor/Executor.cs
@@ -4,13 +4,7 @@
 
 public class Executor
 {
-    private static void test(bool b)
-    {
-        if (!b)
-        {
-            throw new System.Exception();
-        }
-    }
+    private static void test(bool b) => global::Test.TestHelper.test(b);
 
     public Executor()
     {
diff --git a/csharp/test/Ice/executor/TestI.cs b/csharp/test/Ice/executor/TestI.cs
index 24fc5d2f485..767d4138c9f 100644
--- a/csharp/test/Ice/executor/TestI.cs
+++ b/csharp/test/Ice/executor/TestI.cs
@@ -4,13 +4,7 @@
 
 public class TestI : TestIntfDisp_
 {
-    private static void test(bool b)
-    {
-        if (!b)
-        {
-            throw new System.Exception();
-        }
-    }
+    private static void test(bool b) => global::Test.TestHelper.test(b);
 
     public TestI()
     {
@@ -43,13 +37,7 @@ public override void
 
 public class TestControllerI : TestIntfControllerDisp_
 {
-    private static void test(bool b)
-    {
-        if (!b)
-        {
-            throw new System.Exception();
-        }
-    }
+    private static void test(bool b) => global::Test.TestHelper.test(b);
 
     public override void
     holdAdapter(Ice.Current current)
diff --git a/csharp/test/Ice/hold/HoldI.cs b/csharp/test/Ice/hold/HoldI.cs
index d7d6a92eea4..200473f2339 100644
--- a/csharp/test/Ice/hold/HoldI.cs
+++ b/csharp/test/Ice/hold/HoldI.cs
@@ -8,13 +8,7 @@ public sealed class HoldI : Test.HoldDisp_
     private int _last = 0;
     private readonly object _taskMutex = new object();
 
-    private static void test(bool b)
-    {
-        if (!b)
-        {
-            throw new System.Exception();
-        }
-    }
+    private static void test(bool b) => global::Test.TestHelper.test(b);
 
     public HoldI(Ice.ObjectAdapter adapter) => _adapter = adapter;
 
diff --git a/csharp/test/Ice/operations/BatchOneways.cs b/csharp/test/Ice/operations/BatchOneways.cs
index 1d12ffb260f..b8b8a91c979 100644
--- a/csharp/test/Ice/operations/BatchOneways.cs
+++ b/csharp/test/Ice/operations/BatchOneways.cs
@@ -6,13 +6,7 @@ namespace operations
     {
         internal class BatchOneways
         {
-            private static void test(bool b)
-            {
-                if (!b)
-                {
-                    throw new System.Exception();
-                }
-            }
+            private static void test(bool b) => global::Test.TestHelper.test(b);
 
             private class BatchRequestInterceptorI
             {
diff --git a/csharp/test/Ice/operations/BatchOnewaysAMI.cs b/csharp/test/Ice/operations/BatchOnewaysAMI.cs
index fb89455edfc..bf7fbd0cf83 100644
--- a/csharp/test/Ice/operations/BatchOnewaysAMI.cs
+++ b/csharp/test/Ice/operations/BatchOnewaysAMI.cs
@@ -8,13 +8,7 @@ namespace operations
     {
         internal class BatchOnewaysAMI
         {
-            private static void test(bool b)
-            {
-                if (!b)
-                {
-                    throw new System.Exception();
-                }
-            }
+            private static void test(bool b) => global::Test.TestHelper.test(b);
 
             private class Callback
             {
diff --git a/csharp/test/Ice/operations/MyDerivedClassAMDI.cs b/csharp/test/Ice/operations/MyDerivedClassAMDI.cs
index e1fd63dfe1d..8cc50d67aa6 100644
--- a/csharp/test/Ice/operations/MyDerivedClassAMDI.cs
+++ b/csharp/test/Ice/operations/MyDerivedClassAMDI.cs
@@ -8,13 +8,7 @@ namespace AMD
         {
             public sealed class MyDerivedClassI : Test.MyDerivedClassDisp_
             {
-                private static void test(bool b)
-                {
-                    if (!b)
-                    {
-                        throw new System.Exception();
-                    }
-                }
+                private static void test(bool b) => global::Test.TestHelper.test(b);
 
                 internal class Thread_opVoid : TaskCompletionSource<object>
                 {
diff --git a/csharp/test/Ice/operations/MyDerivedClassI.cs b/csharp/test/Ice/operations/MyDerivedClassI.cs
index 1d9d4d084bb..315b0cfaaf6 100644
--- a/csharp/test/Ice/operations/MyDerivedClassI.cs
+++ b/csharp/test/Ice/operations/MyDerivedClassI.cs
@@ -6,13 +6,7 @@ namespace operations
     {
         public sealed class MyDerivedClassI : Test.MyDerivedClassDisp_
         {
-            private static void test(bool b)
-            {
-                if (!b)
-                {
-                    throw new System.Exception();
-                }
-            }
+            private static void test(bool b) => global::Test.TestHelper.test(b);
 
             public override void shutdown(Ice.Current current)
             {
diff --git a/csharp/test/Ice/operations/Oneways.cs b/csharp/test/Ice/operations/Oneways.cs
index 5d64ef63996..5187973d89d 100644
--- a/csharp/test/Ice/operations/Oneways.cs
+++ b/csharp/test/Ice/operations/Oneways.cs
@@ -6,13 +6,7 @@ namespace operations
     {
         internal class Oneways
         {
-            private static void test(bool b)
-            {
-                if (!b)
-                {
-                    throw new System.SystemException();
-                }
-            }
+            private static void test(bool b) => global::Test.TestHelper.test(b);
 
             internal static void oneways(global::Test.TestHelper helper, Test.MyClassPrx p)
             {
diff --git a/csharp/test/Ice/operations/OnewaysAMI.cs b/csharp/test/Ice/operations/OnewaysAMI.cs
index 1f26de3cc54..06874fac503 100644
--- a/csharp/test/Ice/operations/OnewaysAMI.cs
+++ b/csharp/test/Ice/operations/OnewaysAMI.cs
@@ -6,13 +6,7 @@ namespace operations
     {
         public class OnewaysAMI
         {
-            private static void test(bool b)
-            {
-                if (!b)
-                {
-                    throw new System.Exception();
-                }
-            }
+            private static void test(bool b) => global::Test.TestHelper.test(b);
 
             internal static async Task onewaysAMI(Test.MyClassPrx proxy)
             {
diff --git a/csharp/test/Ice/operations/Twoways.cs b/csharp/test/Ice/operations/Twoways.cs
index 6702ff83ffb..4ef58cff776 100644
--- a/csharp/test/Ice/operations/Twoways.cs
+++ b/csharp/test/Ice/operations/Twoways.cs
@@ -6,13 +6,7 @@ namespace operations
     {
         internal class Twoways
         {
-            private static void test(bool b)
-            {
-                if (!b)
-                {
-                    throw new System.Exception();
-                }
-            }
+            private static void test(bool b) => global::Test.TestHelper.test(b);
 
             private class PerThreadContextInvokeThread
             {
diff --git a/csharp/test/Ice/operations/TwowaysAMI.cs b/csharp/test/Ice/operations/TwowaysAMI.cs
index 0d0e49aa997..a85118cf71d 100644
--- a/csharp/test/Ice/operations/TwowaysAMI.cs
+++ b/csharp/test/Ice/operations/TwowaysAMI.cs
@@ -6,13 +6,7 @@ namespace operations
     {
         public class TwowaysAMI
         {
-            private static void test(bool b)
-            {
-                if (!b)
-                {
-                    throw new System.Exception();
-                }
-            }
+            private static void test(bool b) => global::Test.TestHelper.test(b);
 
             internal static async Task twowaysAMI(global::Test.TestHelper helper, Test.MyClassPrx p)
             {
diff --git a/csharp/test/Ice/plugin/BasePlugin.cs b/csharp/test/Ice/plugin/BasePlugin.cs
index 5274e5d5b1b..950c9b11087 100644
--- a/csharp/test/Ice/plugin/BasePlugin.cs
+++ b/csharp/test/Ice/plugin/BasePlugin.cs
@@ -17,13 +17,7 @@ public bool isDestroyed()
         return _destroyed;
     }
 
-    protected static void test(bool b)
-    {
-        if (!b)
-        {
-            throw new System.Exception();
-        }
-    }
+    protected static void test(bool b) => global::Test.TestHelper.test(b);
 
     public abstract void initialize();
     public abstract void destroy();
diff --git a/csharp/test/Ice/plugin/BasePluginFail.cs b/csharp/test/Ice/plugin/BasePluginFail.cs
index 2fb91ac5a42..0947ab5104b 100644
--- a/csharp/test/Ice/plugin/BasePluginFail.cs
+++ b/csharp/test/Ice/plugin/BasePluginFail.cs
@@ -19,13 +19,7 @@ public bool isDestroyed()
         return _destroyed;
     }
 
-    protected static void test(bool b)
-    {
-        if (!b)
-        {
-            throw new System.Exception();
-        }
-    }
+    protected static void test(bool b) => global::Test.TestHelper.test(b);
 
     public abstract void initialize();
     public abstract void destroy();
diff --git a/csharp/test/Ice/plugin/PluginFactory.cs b/csharp/test/Ice/plugin/PluginFactory.cs
index 2cde4648c0c..44743700cfd 100644
--- a/csharp/test/Ice/plugin/PluginFactory.cs
+++ b/csharp/test/Ice/plugin/PluginFactory.cs
@@ -40,13 +40,7 @@ public void destroy()
             }
         }
 
-        private static void test(bool b)
-        {
-            if (!b)
-            {
-                throw new System.Exception();
-            }
-        }
+        private static void test(bool b) => global::Test.TestHelper.test(b);
 
         private bool _initialized = false;
         private bool _destroyed = false;
diff --git a/csharp/test/Ice/plugin/PluginInitializeFailFactory.cs b/csharp/test/Ice/plugin/PluginInitializeFailFactory.cs
index 97ed300626e..f5a1ca109fe 100644
--- a/csharp/test/Ice/plugin/PluginInitializeFailFactory.cs
+++ b/csharp/test/Ice/plugin/PluginInitializeFailFactory.cs
@@ -16,15 +16,7 @@ public void initialize()
 
         public void destroy()
         {
-            test(false);
-        }
-
-        private static void test(bool b)
-        {
-            if (!b)
-            {
-                throw new System.Exception();
-            }
+            global::Test.TestHelper.test(false);
         }
     }
 }
diff --git a/csharp/test/Ice/plugin/msbuild/plugin/plugin.csproj b/csharp/test/Ice/plugin/msbuild/plugin/plugin.csproj
index 1bb817767ea..e293de1b735 100644
--- a/csharp/test/Ice/plugin/msbuild/plugin/plugin.csproj
+++ b/csharp/test/Ice/plugin/msbuild/plugin/plugin.csproj
@@ -21,6 +21,7 @@
     <Compile Include="../../PluginThreeFailFactory.cs" />
     <Compile Include="../../PluginTwoFactory.cs" />
     <Compile Include="../../PluginTwoFailFactory.cs" />
+    <Compile Include="../../../../TestCommon/TestHelper.cs" />
   </ItemGroup>
   <ItemGroup>
     <PackageReference Include="zeroc.icebuilder.msbuild" Version="5.0.9" />
diff --git a/csharp/test/Ice/seqMapping/Twoways.cs b/csharp/test/Ice/seqMapping/Twoways.cs
index 4f5d09d4bd4..3ff5de94610 100644
--- a/csharp/test/Ice/seqMapping/Twoways.cs
+++ b/csharp/test/Ice/seqMapping/Twoways.cs
@@ -6,13 +6,7 @@ namespace seqMapping
     {
         internal class Twoways
         {
-            private static void test(bool b)
-            {
-                if (!b)
-                {
-                    throw new System.Exception();
-                }
-            }
+            private static void test(bool b) => global::Test.TestHelper.test(b);
 
             private static int _length = 100;
 
diff --git a/csharp/test/Ice/seqMapping/TwowaysAMI.cs b/csharp/test/Ice/seqMapping/TwowaysAMI.cs
index df1f9f1bb5e..904a440b527 100644
--- a/csharp/test/Ice/seqMapping/TwowaysAMI.cs
+++ b/csharp/test/Ice/seqMapping/TwowaysAMI.cs
@@ -6,13 +6,7 @@ namespace seqMapping
     {
         public class TwowaysAMI
         {
-            private static void test(bool b)
-            {
-                if (!b)
-                {
-                    throw new System.SystemException();
-                }
-            }
+            private static void test(bool b) => global::Test.TestHelper.test(b);
 
             private static readonly int _length = 100;
 
diff --git a/csharp/test/Ice/servantLocator/ServantLocatorAMDI.cs b/csharp/test/Ice/servantLocator/ServantLocatorAMDI.cs
index 04aecec7d40..b1644bf7474 100644
--- a/csharp/test/Ice/servantLocator/ServantLocatorAMDI.cs
+++ b/csharp/test/Ice/servantLocator/ServantLocatorAMDI.cs
@@ -23,13 +23,7 @@ public ServantLocatorI(String category)
                     }
                 }
 
-                private static void test(bool b)
-                {
-                    if (!b)
-                    {
-                        throw new System.Exception();
-                    }
-                }
+                private static void test(bool b) => global::Test.TestHelper.test(b);
 
                 public Ice.Object locate(Ice.Current current, out object cookie)
                 {
diff --git a/csharp/test/Ice/servantLocator/ServantLocatorI.cs b/csharp/test/Ice/servantLocator/ServantLocatorI.cs
index 1450019a575..0f1f4555bf9 100644
--- a/csharp/test/Ice/servantLocator/ServantLocatorI.cs
+++ b/csharp/test/Ice/servantLocator/ServantLocatorI.cs
@@ -21,13 +21,7 @@ public ServantLocatorI(string category)
                 }
             }
 
-            private static void test(bool b)
-            {
-                if (!b)
-                {
-                    throw new System.Exception();
-                }
-            }
+            private static void test(bool b) => global::Test.TestHelper.test(b);
 
             public Ice.Object locate(Ice.Current current, out object cookie)
             {
diff --git a/csharp/test/Ice/slicing/objects/TestAMDI.cs b/csharp/test/Ice/slicing/objects/TestAMDI.cs
index 503bb84bb48..579504efa91 100644
--- a/csharp/test/Ice/slicing/objects/TestAMDI.cs
+++ b/csharp/test/Ice/slicing/objects/TestAMDI.cs
@@ -4,13 +4,7 @@
 
 public sealed class TestI : TestIntfDisp_
 {
-    private static void test(bool b)
-    {
-        if (!b)
-        {
-            throw new Exception();
-        }
-    }
+    private static void test(bool b) => global::Test.TestHelper.test(b);
 
     public override Task shutdownAsync(Ice.Current current)
     {
diff --git a/csharp/test/Ice/slicing/objects/TestI.cs b/csharp/test/Ice/slicing/objects/TestI.cs
index 8f584ffbc3d..91761784812 100644
--- a/csharp/test/Ice/slicing/objects/TestI.cs
+++ b/csharp/test/Ice/slicing/objects/TestI.cs
@@ -4,13 +4,7 @@
 
 public sealed class TestI : TestIntfDisp_
 {
-    private static void test(bool b)
-    {
-        if (!b)
-        {
-            throw new Exception();
-        }
-    }
+    private static void test(bool b) => global::Test.TestHelper.test(b);
 
     public override void shutdown(Ice.Current current)
     {
diff --git a/csharp/test/IceSSL/configuration/AllTests.cs b/csharp/test/IceSSL/configuration/AllTests.cs
index e3ddd199be5..4c0ae88b53b 100644
--- a/csharp/test/IceSSL/configuration/AllTests.cs
+++ b/csharp/test/IceSSL/configuration/AllTests.cs
@@ -9,16 +9,8 @@
 using System.Security.Cryptography.X509Certificates;
 using Test;
 
-public class AllTests
+public class AllTests : global::Test.AllTests
 {
-    private static void test(bool b)
-    {
-        if (!b)
-        {
-            throw new Exception();
-        }
-    }
-
     private static X509Certificate2 createCertificate(string certPEM)
     {
         return new X509Certificate2(System.Text.Encoding.ASCII.GetBytes(certPEM));
diff --git a/csharp/test/IceSSL/configuration/TestI.cs b/csharp/test/IceSSL/configuration/TestI.cs
index 3e376d802b5..50f708e247e 100644
--- a/csharp/test/IceSSL/configuration/TestI.cs
+++ b/csharp/test/IceSSL/configuration/TestI.cs
@@ -60,26 +60,14 @@ internal void destroy()
         _communicator.destroy();
     }
 
-    private static void test(bool b)
-    {
-        if (!b)
-        {
-            throw new Exception();
-        }
-    }
+    private static void test(bool b) => global::Test.TestHelper.test(b);
 
     private Ice.Communicator _communicator;
 }
 
 internal sealed class ServerFactoryI : ServerFactoryDisp_
 {
-    private static void test(bool b)
-    {
-        if (!b)
-        {
-            throw new Exception();
-        }
-    }
+    private static void test(bool b) => global::Test.TestHelper.test(b);
 
     public ServerFactoryI(string defaultDir)
     {