Imported Upstream version 4.6.0.125

Former-commit-id: a2155e9bd80020e49e72e86c44da02a8ac0e57a4

mcs/class/referencesource/System.Activities/System/Activities/Debugger/UnitTestUtility.cs

@@ -0,0 +1,43 @@
+// <copyright>
+//   Copyright (c) Microsoft Corporation.  All rights reserved.
+// </copyright>
+
+namespace System.Activities.Debugger
+{
+    using System;
+    using System.Runtime;
+
+    internal static class UnitTestUtility
+    {
+        internal static Func<string, Exception> AssertionExceptionFactory
+        {
+            get;
+            set;
+        }
+
+        internal static void TestInitialize(Func<string, Exception> createAssertionException)
+        {
+            UnitTestUtility.AssertionExceptionFactory = createAssertionException;
+        }
+
+        internal static void TestCleanup()
+        {
+            UnitTestUtility.AssertionExceptionFactory = null;
+        }
+
+        internal static void Assert(bool condition, string assertionMessage)
+        {
+            if (UnitTestUtility.AssertionExceptionFactory != null)
+            {
+                if (!condition)
+                {
+                    throw FxTrace.Exception.AsError(UnitTestUtility.AssertionExceptionFactory(assertionMessage));
+                }
+            }
+            else
+            {
+                Fx.Assert(condition, assertionMessage);
+            }
+        }
+    }
+}