Change Activity Default IdFormat to W3C

src/libraries/System.Diagnostics.DiagnosticSource/src/System.Diagnostics.DiagnosticSource.csproj

@@ -48,6 +48,10 @@
   </ItemGroup>
   <ItemGroup Condition=" '$(TargetFramework)' != 'net45' And '$(TargetFramework)' != 'netstandard1.1'">
     <Compile Include="System\Diagnostics\Activity.Current.net46.cs" />
+    <Compile Include="System\Diagnostics\LocalAppContextSwitches.cs" />
+    <Compile Include="$(CommonPath)System\LocalAppContextSwitches.Common.cs">
+      <Link>Common\System\LocalAppContextSwitches.Common.cs</Link>
+    </Compile>
   </ItemGroup>
   <ItemGroup Condition=" '$(TargetFramework)' == 'net45' ">
     <Compile Include="System\Diagnostics\Activity.Current.net45.cs" />
@@ -82,6 +86,9 @@
     <Reference Include="System.Threading" />
     <Reference Include="System.Resources.ResourceManager" />
   </ItemGroup>
+  <ItemGroup Condition="'$(TargetFramework)' == 'netstandard1.3'">
+    <Reference Include="System.AppContext" />
+  </ItemGroup>
   <ItemGroup Condition="$(TargetFramework.StartsWith('net4'))">
     <Compile Include="AssemblyInfo.netfx.cs" />
     <Compile Include="System\Diagnostics\Activity.DateTime.netfx.cs" />

src/libraries/System.Diagnostics.DiagnosticSource/src/System/Diagnostics/Activity.cs

@@ -51,7 +51,7 @@ public partial class Activity : IDisposable
         private static ActivityIdFormat s_defaultIdFormat;
         /// <summary>
         /// Normally if the ParentID is defined, the format of that is used to determine the
-        /// format used by the Activity.   However if ForceDefaultFormat is set to true, the
+        /// format used by the Activity. However if ForceDefaultFormat is set to true, the
         /// ID format will always be the DefaultIdFormat even if the ParentID is define and is
         /// a different format.
         /// </summary>
@@ -735,7 +735,13 @@ public static ActivityIdFormat DefaultIdFormat
             get
             {
                 if (s_defaultIdFormat == ActivityIdFormat.Unknown)
+                {
+#if NO_EVENTSOURCE_COMPLEX_TYPE_SUPPORT
                     s_defaultIdFormat = ActivityIdFormat.Hierarchical;
+#else
+                    s_defaultIdFormat = LocalAppContextSwitches.DefaultActivityIdFormatIsHierarchial ? ActivityIdFormat.Hierarchical : ActivityIdFormat.W3C;
+#endif // NO_EVENTSOURCE_COMPLEX_TYPE_SUPPORT
+                }
                 return s_defaultIdFormat;
             }
             set

src/libraries/System.Diagnostics.DiagnosticSource/src/System/Diagnostics/LocalAppContextSwitches.cs

@@ -0,0 +1,18 @@
+// Licensed to the .NET Foundation under one or more agreements.
+// The .NET Foundation licenses this file to you under the MIT license.
+// See the LICENSE file in the project root for more information.
+
+using System.Runtime.CompilerServices;
+
+namespace System
+{
+    internal static partial class LocalAppContextSwitches
+    {
+        private static int s_defaultActivityIdFormatIsHierarchial;
+        public static bool DefaultActivityIdFormatIsHierarchial
+        {
+            [MethodImpl(MethodImplOptions.AggressiveInlining)]
+            get => GetCachedSwitchValue("System.Diagnostics.DefaultActivityIdFormatIsHierarchial", ref s_defaultActivityIdFormatIsHierarchial);
+        }
+    }
+}

src/libraries/System.Diagnostics.DiagnosticSource/tests/ActivityTests.cs

@@ -210,8 +210,6 @@ public void ActivityIdNonHierarchicalOverflow()
 
             Assert.Equal(parentId, activity.ParentId);
 
-            // With probability 1/MaxLong, Activity.Id length may be expectedIdLength + 1
-            Assert.InRange(activity.Id.Length, expectedIdLength, expectedIdLength + 1);
             Assert.DoesNotContain('#', activity.Id);
         }
 
@@ -258,6 +256,7 @@ public void IdGenerationNoParent()
         public void IdGenerationInternalParent()
         {
             var parent = new Activity("parent");
+            parent.SetIdFormat(ActivityIdFormat.Hierarchical);
             parent.Start();
             var child1 = new Activity("child1");
             var child2 = new Activity("child2");
@@ -539,7 +538,7 @@ public void IdFormat_HierarchicalIsDefault()
         {
             Activity activity = new Activity("activity1");
             activity.Start();
-            Assert.Equal(ActivityIdFormat.Hierarchical, activity.IdFormat);
+            Assert.Equal(ActivityIdFormat.W3C, activity.IdFormat);
         }
 
         [Fact]
@@ -637,9 +636,9 @@ public void IdFormat_ZeroTraceIdAndSpanIdWithHierarchicalFormat()
         {
             Activity activity = new Activity("activity");
             activity.Start();
-            Assert.Equal(ActivityIdFormat.Hierarchical, activity.IdFormat);
-            Assert.Equal("00000000000000000000000000000000", activity.TraceId.ToHexString());
-            Assert.Equal("0000000000000000", activity.SpanId.ToHexString());
+            Assert.Equal(ActivityIdFormat.W3C, activity.IdFormat);
+            Assert.NotEqual("00000000000000000000000000000000", activity.TraceId.ToHexString());
+            Assert.NotEqual("0000000000000000", activity.SpanId.ToHexString());
         }
 
         [ConditionalFact(typeof(RemoteExecutor), nameof(RemoteExecutor.IsSupported))]

src/libraries/System.Diagnostics.DiagnosticSource/tests/TestWithConfigSwitches/ActivityTests.cs

@@ -0,0 +1,106 @@
+// Licensed to the .NET Foundation under one or more agreements.
+// The .NET Foundation licenses this file to you under the MIT license.
+// See the LICENSE file in the project root for more information.
+
+using System.Threading.Tasks;
+using Xunit;
+
+namespace System.Diagnostics.Tests
+{
+    public class ActivityTests : IDisposable
+    {
+        [Fact]
+        public void ActivityIdNonHierarchicalOverflow()
+        {
+            // find out Activity Id length on this platform in this AppDomain
+            Activity testActivity = new Activity("activity")
+                .Start();
+            var expectedIdLength = testActivity.Id.Length;
+            testActivity.Stop();
+
+            // check that if parentId '|aaa...a' 1024 bytes long is set with single node (no dots or underscores in the Id)
+            // it causes overflow during Id generation, and new root Id is generated for the new Activity
+            var parentId = '|' + new string('a', 1022) + '.';
+
+            var activity = new Activity("activity")
+                .SetParentId(parentId)
+                .Start();
+
+            Assert.Equal(parentId, activity.ParentId);
+
+            // With probability 1/MaxLong, Activity.Id length may be expectedIdLength + 1
+            Assert.InRange(activity.Id.Length, expectedIdLength, expectedIdLength + 1);
+            Assert.DoesNotContain('#', activity.Id);
+        }
+
+        [Fact]
+        public void IdGenerationInternalParent()
+        {
+            var parent = new Activity("parent");
+            parent.Start();
+            var child1 = new Activity("child1");
+            var child2 = new Activity("child2");
+            //start 2 children in different execution contexts
+            Task.Run(() => child1.Start()).Wait();
+            Task.Run(() => child2.Start()).Wait();
+
+            // In Debug builds of System.Diagnostics.DiagnosticSource, the child operation Id will be constructed as follows
+            // "|parent.RootId.<child.OperationName.Replace(., -)>-childCount.".
+            // This is for debugging purposes to know which operation the child Id is comming from.
+            //
+            // In Release builds of System.Diagnostics.DiagnosticSource, it will not contain the operation name to keep it simple and it will be as
+            // "|parent.RootId.childCount.".
+
+            string child1DebugString = $"|{parent.RootId}.{child1.OperationName}-1.";
+            string child2DebugString = $"|{parent.RootId}.{child2.OperationName}-2.";
+            string child1ReleaseString = $"|{parent.RootId}.1.";
+            string child2ReleaseString = $"|{parent.RootId}.2.";
+
+            AssertExtensions.AtLeastOneEquals(child1DebugString, child1ReleaseString, child1.Id);
+            AssertExtensions.AtLeastOneEquals(child2DebugString, child2ReleaseString, child2.Id);
+
+            Assert.Equal(parent.RootId, child1.RootId);
+            Assert.Equal(parent.RootId, child2.RootId);
+            child1.Stop();
+            child2.Stop();
+            var child3 = new Activity("child3");
+            child3.Start();
+
+            string child3DebugString = $"|{parent.RootId}.{child3.OperationName}-3.";
+            string child3ReleaseString = $"|{parent.RootId}.3.";
+
+            AssertExtensions.AtLeastOneEquals(child3DebugString, child3ReleaseString, child3.Id);
+
+            var grandChild = new Activity("grandChild");
+            grandChild.Start();
+
+            child3DebugString = $"{child3.Id}{grandChild.OperationName}-1.";
+            child3ReleaseString = $"{child3.Id}1.";
+
+            AssertExtensions.AtLeastOneEquals(child3DebugString, child3ReleaseString, grandChild.Id);
+        }
+
+        [Fact]
+        public void IdFormat_HierarchicalIsDefault()
+        {
+            Activity activity = new Activity("activity1");
+            activity.Start();
+            Assert.Equal(ActivityIdFormat.Hierarchical, activity.IdFormat);
+        }
+
+        [Fact]
+        public void IdFormat_ZeroTraceIdAndSpanIdWithHierarchicalFormat()
+        {
+            Activity activity = new Activity("activity");
+            activity.Start();
+            Assert.Equal(ActivityIdFormat.Hierarchical, activity.IdFormat);
+            Assert.Equal("00000000000000000000000000000000", activity.TraceId.ToHexString());
+            Assert.Equal("0000000000000000", activity.SpanId.ToHexString());
+        }
+
+        public void Dispose()
+        {
+            Activity.Current = null;
+        }
+    }
+}

src/libraries/System.Diagnostics.DiagnosticSource/tests/TestWithConfigSwitches/System.Diagnostics.DiagnosticSource.Switches.Tests.csproj

@@ -0,0 +1,9 @@
+<Project Sdk="Microsoft.NET.Sdk">
+  <PropertyGroup>
+    <TargetFrameworks>$(NetCoreAppCurrent)</TargetFrameworks>
+    <TestRuntime>true</TestRuntime>
+  </PropertyGroup>
+  <ItemGroup>
+    <Compile Include="ActivityTests.cs" />
+  </ItemGroup>
+</Project>

src/libraries/System.Diagnostics.DiagnosticSource/tests/TestWithConfigSwitches/runtimeconfig.template.json

@@ -0,0 +1,5 @@
+{
+  "configProperties": {
+    "System.Diagnostics.DefaultActivityIdFormatIsHierarchial": true
+  }
+}

src/libraries/System.Drawing.Common/src/System.Drawing.Common.csproj

@@ -219,7 +219,7 @@
     <Compile Include="misc\GDI\DeviceContextType.cs" />
     <Compile Include="misc\GDI\WindowsGraphics.cs" />
     <Compile Include="misc\GDI\WindowsRegion.cs" />
-    <Compile Include="$(CoreLibSharedDir)System\LocalAppContextSwitches.Common.cs"
+    <Compile Include="$(CommonPath)System\LocalAppContextSwitches.Common.cs"
              Link="System\LocalAppContextSwitches.Common.cs" />
     <Compile Include="$(CommonPath)Interop\Windows\Interop.Libraries.cs"
              Link="Common\Interop\Windows\Interop.Libraries.cs" />

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

@@ -386,7 +386,6 @@
     <Compile Include="$(MSBuildThisFileDirectory)System\LazyOfTTMetadata.cs" />
     <Compile Include="$(MSBuildThisFileDirectory)System\LoaderOptimization.cs" />
     <Compile Include="$(MSBuildThisFileDirectory)System\LoaderOptimizationAttribute.cs" />
-    <Compile Include="$(MSBuildThisFileDirectory)System\LocalAppContextSwitches.Common.cs" />
     <Compile Include="$(MSBuildThisFileDirectory)System\LocalAppContextSwitches.cs" />
     <Compile Include="$(MSBuildThisFileDirectory)System\LocalDataStoreSlot.cs" />
     <Compile Include="$(MSBuildThisFileDirectory)System\MarshalByRefObject.cs" />
@@ -1061,6 +1060,9 @@
     <Compile Include="$(CommonPath)SkipLocalsInit.cs">
       <Link>Common\SkipLocalsInit.cs</Link>
     </Compile>
+    <Compile Include="$(CommonPath)System\LocalAppContextSwitches.Common.cs">
+      <Link>Common\System\LocalAppContextSwitches.Common.cs</Link>
+    </Compile>
     <Compile Include="$(CommonPath)System\HResults.cs">
       <Link>Common\System\HResults.cs</Link>
     </Compile>

src/libraries/System.Private.Xml/src/System.Private.Xml.csproj

@@ -791,7 +791,7 @@
     <Compile Include="System\Xml\Xsl\Xslt\XsltLoader.cs" />
     <Compile Include="System\Xml\Xsl\Xslt\XsltQilFactory.cs" />
     <Compile Include="System\Xml\Xsl\Xslt\XslVisitor.cs" />
-    <Compile Include="$(CoreLibSharedDir)System\LocalAppContextSwitches.Common.cs"
+    <Compile Include="$(CommonPath)System\LocalAppContextSwitches.Common.cs"
              Link="System\LocalAppContextSwitches.Common.cs" />
     <Compile Include="System\Xml\Core\LocalAppContextSwitches.cs" />
     <Compile Include="$(CommonPath)System\CSharpHelpers.cs" />