Merge pull request #9193 from tmat/StackFormatterRegression

Fix regression in interactive stack printing

src/Interactive/Features/Interactive/Core/InteractiveHost.Service.cs

@@ -820,7 +820,7 @@ private async Task<ScriptState<object>> ExecuteOnUIThread(Script<object> script,
                         }
                         catch (Exception e)
                         {
-                            Console.Error.WriteLine(_replServiceProvider.ObjectFormatter.FormatException(e));
+                            Console.Error.Write(_replServiceProvider.ObjectFormatter.FormatException(e));
                             return null;
                         }
                     }))).ConfigureAwait(false);

src/Scripting/CSharpTest/ObjectFormatterTests.cs

@@ -906,6 +906,38 @@ public void StackTrace_GenericMethodInGenericType()
 $@"Exception of type 'System.Exception' was thrown.
   + Microsoft.CodeAnalysis.CSharp.Scripting.Hosting.UnitTests.ObjectFormatterTests.Fixture<T>.Method<U>(){string.Format(ScriptingResources.AtFileLine, filePath, 10027)}
   + Microsoft.CodeAnalysis.CSharp.Scripting.Hosting.UnitTests.ObjectFormatterTests.StackTrace_GenericMethodInGenericType(){string.Format(ScriptingResources.AtFileLine, filePath, 10101)}
+";
+                var actual = s_formatter.FormatException(e);
+                Assert.Equal(expected, actual);
+            }
+        }
+
+        private static class Fixture2
+        {
+            [MethodImpl(MethodImplOptions.NoInlining)]
+            public static void MethodDynamic()
+            {
+                ((dynamic)new object()).x();
+            }
+        }
+
+        [Fact]
+        public void StackTrace_Dynamic()
+        {
+            try
+            {
+                Fixture2.MethodDynamic();
+                Assert.False(true);
+            }
+            catch (Exception e)
+            {
+                const string filePath = @"z:\Fixture.cs";
+
+                var expected =
+$@"'object' does not contain a definition for 'x'
+  + System.Dynamic.UpdateDelegates.UpdateAndExecuteVoid1<T0>(System.Runtime.CompilerServices.CallSite, T0)
+  + Microsoft.CodeAnalysis.CSharp.Scripting.Hosting.UnitTests.ObjectFormatterTests.Fixture2.MethodDynamic(){string.Format(ScriptingResources.AtFileLine, filePath, 10123)}
+  + Microsoft.CodeAnalysis.CSharp.Scripting.Hosting.UnitTests.ObjectFormatterTests.StackTrace_Dynamic(){string.Format(ScriptingResources.AtFileLine, filePath, 10132)}
 ";
                 var actual = s_formatter.FormatException(e);
                 Assert.Equal(expected, actual);

src/Scripting/Core/Hosting/CommonMemberFilter.cs

@@ -26,8 +26,9 @@ public override bool Include(StackFrame frame)
                 return false;
             }
 
+            // Type is null for DynamicMethods and global methods.
             // TODO (tomat): we don't want to include awaiter helpers, shouldn't they be marked by DebuggerHidden in FX?
-            if (IsTaskAwaiter(type) || IsTaskAwaiter(type.DeclaringType))
+            if (type == null || IsTaskAwaiter(type) || IsTaskAwaiter(type.DeclaringType))
             {
                 return false;
             }
@@ -44,8 +45,10 @@ private bool IsHiddenMember(MemberInfo info)
         {
             while (info != null)
             {
+                // GetCustomAttributes returns null when called on DynamicMethod 
+                // (bug https://github.com/dotnet/corefx/issues/6402)
                 if (IsGeneratedMemberName(info.Name) ||
-                    info.GetCustomAttributes<DebuggerHiddenAttribute>().Any())
+                    info.GetCustomAttributes<DebuggerHiddenAttribute>()?.Any() == true)
                 {
                     return true;
                 }