From 70d0179d8589ba1b305451e34063f5a6619a98b5 Mon Sep 17 00:00:00 2001
From: Nolan Glore <nglore@microsoft.com>
Date: Tue, 9 Jun 2020 15:36:38 -0700
Subject: [PATCH] Fix null ref bug when base class cleanup fails when there is
 no derived class cleanup method

---
 .../MSTest.CoreAdapter/Execution/TestClassInfo.cs  |  8 +++++---
 .../Execution/TestClassInfoTests.cs                | 14 ++++++++++++++
 2 files changed, 19 insertions(+), 3 deletions(-)

diff --git a/src/Adapter/MSTest.CoreAdapter/Execution/TestClassInfo.cs b/src/Adapter/MSTest.CoreAdapter/Execution/TestClassInfo.cs
index 433f4a8a68..4ef28aba40 100644
--- a/src/Adapter/MSTest.CoreAdapter/Execution/TestClassInfo.cs
+++ b/src/Adapter/MSTest.CoreAdapter/Execution/TestClassInfo.cs
@@ -345,9 +345,11 @@ public string RunClassCleanup()
 
             if (this.IsClassInitializeExecuted || this.ClassInitializeMethod is null)
             {
+                MethodInfo classCleanupMethod = null;
+
                 try
                 {
-                    var classCleanupMethod = this.ClassCleanupMethod;
+                    classCleanupMethod = this.ClassCleanupMethod;
                     classCleanupMethod?.InvokeAsSynchronousTask(null);
                     var baseClassCleanupQueue = new Queue<MethodInfo>(this.BaseClassCleanupMethodsStack);
                     while (baseClassCleanupQueue.Count > 0)
@@ -378,8 +380,8 @@ public string RunClassCleanup()
                     return string.Format(
                         CultureInfo.CurrentCulture,
                         Resource.UTA_ClassCleanupMethodWasUnsuccesful,
-                        this.ClassType.Name,
-                        this.ClassCleanupMethod.Name,
+                        classCleanupMethod.DeclaringType.Name,
+                        classCleanupMethod.Name,
                         errorMessage,
                         StackTraceHelper.GetStackTraceInformation(realException)?.ErrorStackTrace);
                 }
diff --git a/test/UnitTests/MSTest.CoreAdapter.Unit.Tests/Execution/TestClassInfoTests.cs b/test/UnitTests/MSTest.CoreAdapter.Unit.Tests/Execution/TestClassInfoTests.cs
index aff4f3c6e6..9142aa4d2c 100644
--- a/test/UnitTests/MSTest.CoreAdapter.Unit.Tests/Execution/TestClassInfoTests.cs
+++ b/test/UnitTests/MSTest.CoreAdapter.Unit.Tests/Execution/TestClassInfoTests.cs
@@ -544,6 +544,20 @@ public void RunClassCleanupShouldReturnExceptionDetailsOfNonAssertExceptions()
                 "Class Cleanup method DummyTestClass.ClassCleanupMethod failed. Error Message: System.ArgumentException: Argument Exception. Stack Trace:     at Microsoft.VisualStudio.TestPlatform.MSTestAdapter.UnitTests.Execution.TestClassInfoTests.<>c.<RunClassCleanupShouldReturnExceptionDetailsOfNonAssertExceptions>");
         }
 
+        [TestMethod]
+        public void RunBaseClassCleanupWithNoDerivedClassCleanupShouldReturnExceptionDetailsOfNonAssertExceptions()
+        {
+            DummyBaseTestClass.ClassCleanupMethodBody = () => { throw new ArgumentException("Argument Exception"); };
+
+            this.testClassInfo.ClassCleanupMethod = null;
+            this.testClassInfo.BaseClassInitAndCleanupMethods.Enqueue(
+                Tuple.Create((MethodInfo)null, typeof(DummyBaseTestClass).GetMethod("CleanupClassMethod")));
+            this.testClassInfo.BaseClassCleanupMethodsStack.Push(typeof(DummyBaseTestClass).GetMethod("CleanupClassMethod"));
+            StringAssert.StartsWith(
+                this.testClassInfo.RunClassCleanup(),
+                "Class Cleanup method DummyBaseTestClass.CleanupClassMethod failed. Error Message: System.ArgumentException: Argument Exception. Stack Trace:     at Microsoft.VisualStudio.TestPlatform.MSTestAdapter.UnitTests.Execution.TestClassInfoTests.<>c.<RunBaseClassCleanupWithNoDerivedClassCleanupShouldReturnExceptionDetailsOfNonAssertExceptions>");
+        }
+
         [TestMethod]
         public void RunBaseClassCleanupEvenIfThereIsNoDerivedClassCleanup()
         {