Shift Most of Wasm AOT test build to helix

docs/workflow/testing/libraries/testing-wasm.md

@@ -144,6 +144,21 @@ At the moment supported values are:
 
 By default, `chrome` browser is used.
 
+## AOT library tests
+
+- Building library tests with AOT, and (even) with `EnableAggressiveTrimming` takes 3-9mins on CI, and that adds up for all the assemblies, causing
+a large build time. To circumvent that on CI, we build the test assemblies on the build machine, but skip the WasmApp build part of it, since
+that includes the expensive AOT step.
+
+- Instead, we take the built test assembly+dependencies, and enough related bits to be able to run the `WasmBuildApp` target, with the original
+inputs.
+
+- To recreate a similar build+test run locally, add `/p:BuildAOTTestsOnHelix=true` to the usual command line.
+- For example, with `./dotnet.sh build /t:Test src/libraries/System.AppContext/tests /p:TargetOS=Browser /p:TargetArchitecture=wasm /p:Configuration=Release`
+
+    - AOT:  add `/p:EnableAggressiveTrimming=true /p:RunAOTCompilation=true /p:BuildAOTTestsOnHelix=true`
+    - Only trimming (helpful to isolate issues caused by trimming):
+        - add `/p:EnableAggressiveTrimming=true /p:BuildAOTTestsOnHelix=true`
 ## Debugging
 
 ### Getting more information

eng/pipelines/common/platform-matrix.yml

@@ -219,7 +219,7 @@ jobs:
       targetRid: browser-wasm
       platform: Browser_wasm
       container:
-        image: ubuntu-18.04-webassembly-20210223133559-4800846
+        image: ubuntu-18.04-webassembly-20210309143118-005aab4
         registry: mcr
       jobParameters:
         runtimeFlavor: ${{ parameters.runtimeFlavor }}

eng/pipelines/runtime-staging.yml

@@ -205,8 +205,47 @@ jobs:
     jobParameters:
       testGroup: innerloop
       nameSuffix: AllSubsets_Mono_AOT
-      buildArgs: -s mono+libs+host+packs+libs.tests -c $(_BuildConfig) /p:ArchiveTests=true /p:EnableAggressiveTrimming=true /p:RunAOTCompilation=true
-      timeoutInMinutes: 120
+      buildArgs: -s mono+libs+host+packs+libs.tests -c $(_BuildConfig) /p:ArchiveTests=true /p:EnableAggressiveTrimming=true /p:BuildAOTTestsOnHelix=true /p:RunAOTCompilation=true
+      timeoutInMinutes: 180
+      condition: >-
+        or(
+          eq(dependencies.evaluate_paths.outputs['SetPathVars_libraries.containsChange'], true),
+          eq(dependencies.evaluate_paths.outputs['SetPathVars_mono.containsChange'], true),
+          eq(dependencies.evaluate_paths.outputs['SetPathVars_installer.containsChange'], true),
+          eq(variables['isFullMatrix'], true))
+      # extra steps, run tests
+      extraStepsTemplate: /eng/pipelines/libraries/helix.yml
+      extraStepsParameters:
+        creator: dotnet-bot
+        testRunNamePrefixSuffix: Mono_$(_BuildConfig)
+        extraHelixArguments: /p:NeedsToBuildWasmAppsOnHelix=true
+        scenarios:
+        - normal
+        condition: >-
+          or(
+          eq(variables['librariesContainsChange'], true),
+          eq(variables['monoContainsChange'], true),
+          eq(variables['isFullMatrix'], true))
+
+- template: /eng/pipelines/common/platform-matrix.yml
+  parameters:
+    jobTemplate: /eng/pipelines/common/global-build-job.yml
+    helixQueuesTemplate: /eng/pipelines/libraries/helix-queues-setup.yml
+    buildConfig: Release
+    runtimeFlavor: mono
+    platforms:
+    - Browser_wasm
+    variables:
+      # map dependencies variables to local variables
+      - name: librariesContainsChange
+        value: $[ dependencies.evaluate_paths.outputs['SetPathVars_libraries.containsChange'] ]
+      - name: monoContainsChange
+        value: $[ dependencies.evaluate_paths.outputs['SetPathVars_mono.containsChange'] ]
+    jobParameters:
+      testGroup: innerloop
+      nameSuffix: AllSubsets_Mono_EAT
+      buildArgs: -s mono+libs+host+packs+libs.tests -c $(_BuildConfig) /p:ArchiveTests=true /p:EnableAggressiveTrimming=true /p:BuildAOTTestsOnHelix=true /p:RunAOTCompilation=false
+      timeoutInMinutes: 180
       condition: >-
         or(
           eq(dependencies.evaluate_paths.outputs['SetPathVars_libraries.containsChange'], true),
@@ -218,6 +257,7 @@ jobs:
       extraStepsParameters:
         creator: dotnet-bot
         testRunNamePrefixSuffix: Mono_$(_BuildConfig)
+        extraHelixArguments: /p:NeedsToBuildWasmAppsOnHelix=true
         scenarios:
         - normal
         condition: >-

eng/testing/ILLink.Descriptor.TestUtilities.xml

@@ -0,0 +1,5 @@
+<linker>
+  <assembly fullname="TestUtilities">
+    <namespace fullname="System" />
+  </assembly>
+</linker>

eng/testing/ILLink.Descriptor.xunit.xml

@@ -12,6 +12,7 @@
   <assembly fullname="Microsoft.DotNet.XUnitExtensions" />
   <assembly fullname="xunit.core">
     <namespace fullname="Xunit" />
+    <namespace fullname="Xunit.Sdk" />
   </assembly>
-  <assembly fullname="xunit.runner.utility.netcoreapp10" /> 
+  <assembly fullname="xunit.runner.utility.netcoreapp10" />
 </linker>

eng/testing/tests.mobile.targets

@@ -167,7 +167,7 @@
       <BundleAssemblies Condition="'$(RunAOTCompilation)' != 'true'" Include="$(PublishDir)*.dll" />
     </ItemGroup>
 
-    <MakeDir Directories="$(_MobileIntermediateOutputPath)" 
+    <MakeDir Directories="$(_MobileIntermediateOutputPath)"
              Condition="'$(RunAOTCompilation)' == 'true'"/>
     <RemoveDir Directories="$(BundleDir)" />
 
@@ -243,7 +243,8 @@
     </ItemGroup>
 
     <ItemGroup>
-      <TrimmerRootDescriptor Include="$(MSBuildThisFileDirectory)ILLink.Descriptor.xunit.xml" />
+      <TrimmerRootDescriptor Include="$(MSBuildThisFileDirectory)ILLink.Descriptor.xunit.xml" Condition="'$(SkipXunitTrimmerDescriptor)' != 'true'"  />
+      <TrimmerRootDescriptor Include="$(MSBuildThisFileDirectory)ILLink.Descriptor.TestUtilities.xml" Condition="'$(SkipTestUtilitiesReference)' != 'true'" />
     </ItemGroup>
   </Target>
 

eng/testing/tests.wasm.targets

@@ -3,6 +3,15 @@
   <PropertyGroup>
     <BundleTestAppTargets>$(BundleTestAppTargets);BundleTestWasmApp</BundleTestAppTargets>
     <DebuggerSupport Condition="'$(DebuggerSupport)' == '' and '$(Configuration)' == 'Debug'">true</DebuggerSupport>
+    <!-- Some tests expect to load satellite assemblies by path, eg. System.Runtime.Loader.Tests,
+         so, just setting it true by default -->
+    <IncludeSatelliteAssembliesInVFS Condition="'$(IncludeSatelliteAssembliesInVFS)' == ''">true</IncludeSatelliteAssembliesInVFS>
+  </PropertyGroup>
+
+  <PropertyGroup>
+    <BuildAOTTestsOn Condition="'$(ContinuousIntegrationBuild)' == 'true' and '$(Scenario)' == 'BuildWasmApps'">helix</BuildAOTTestsOn>
+    <BuildAOTTestsOn Condition="'$(BuildAOTTestsOnHelix)' == 'true'">helix</BuildAOTTestsOn>
+    <BuildAOTTestsOn Condition="'$(BuildAOTTestsOn)' == ''">local</BuildAOTTestsOn>
   </PropertyGroup>
 
   <PropertyGroup Condition="'$(RunScriptCommand)' == ''">
@@ -14,49 +23,119 @@
 
     <_XHarnessArgs Condition="'$(Scenario)' != 'WasmTestOnBrowser'">$(_XHarnessArgs) --engine=$(JSEngine) $(JSEngineArgs) --js-file=runtime.js</_XHarnessArgs>
     <_XHarnessArgs Condition="'$(IsFunctionalTest)' == 'true'"     >$(_XHarnessArgs) --expected-exit-code=$(ExpectedExitCode)</_XHarnessArgs>
-    <_XHarnessArgs Condition="'$(WasmXHarnessArgs)' != '' and '$(OS)' != 'Windows_NT'">$(_XHarnessArgs) $(WasmXHarnessArgs) %24WasmXHarnessArgs</_XHarnessArgs>
-    <_XHarnessArgs Condition="'$(WasmXHarnessArgs)' != '' and '$(OS)' == 'Windows_NT'">$(_XHarnessArgs) $(WasmXHarnessArgs) %WasmXHarnessArgs%</_XHarnessArgs>
+    <_XHarnessArgs Condition="'$(WasmXHarnessArgs)' != ''"         >$(_XHarnessArgs) $(WasmXHarnessArgs)</_XHarnessArgs>
 
     <_AppArgs Condition="'$(IsFunctionalTest)' != 'true' and '$(Scenario)' != 'BuildWasmApps'">--run WasmTestRunner.dll $(AssemblyName).dll</_AppArgs>
     <_AppArgs Condition="'$(IsFunctionalTest)' == 'true'">--run $(AssemblyName).dll --testing</_AppArgs>
 
-    <_AppArgs Condition="'$(WasmTestAppArgs)' != ''">$(_AppArgs) $(WasmTestAppArgs) %24WasmTestAppArgs</_AppArgs>
-    <RunScriptCommand Condition="'$(OS)' != 'Windows_NT'">$HARNESS_RUNNER $(_XHarnessArgs) -- $(WasmXHarnessMonoArgs) %24WasmXHarnessMonoArgs $(_AppArgs)</RunScriptCommand>
-    <RunScriptCommand Condition="'$(OS)' == 'Windows_NT'">%HARNESS_RUNNER% $(_XHarnessArgs) -- $(WasmXHarnessMonoArgs) %WasmXHarnessMonoArgs% $(_AppArgs)</RunScriptCommand>
+    <_AppArgs Condition="'$(WasmTestAppArgs)' != ''">$(_AppArgs) $(WasmTestAppArgs)</_AppArgs>
+
+    <RunScriptCommand Condition="'$(OS)' != 'Windows_NT'">$HARNESS_RUNNER $(_XHarnessArgs) %24WasmXHarnessArgs -- $(WasmXHarnessMonoArgs) %24WasmXHarnessMonoArgs $(_AppArgs) %24WasmTestAppArgs</RunScriptCommand>
+    <RunScriptCommand Condition="'$(OS)' == 'Windows_NT'">$HARNESS_RUNNER $(_XHarnessArgs) %WasmXHarnessArgs%  -- $(WasmXHarnessMonoArgs) %WasmXHarnessMonoArgs% $(_AppArgs) %WasmTestAppArgs%</RunScriptCommand>
+  </PropertyGroup>
+
+  <PropertyGroup Condition="'$(BuildAOTTestsOnHelix)' == 'true'">
+    <_AOTBuildCommand>dotnet msbuild publish/AOTTestProjectForHelix.proj /bl:$XHARNESS_OUT/AOTBuild.binlog</_AOTBuildCommand>
+
+    <!-- running aot-helix tests locally, so we can test with the same project file as CI -->
+    <_AOTBuildCommand Condition="'$(ContinuousIntegrationBuild)' != 'true'">$(_AOTBuildCommand) /p:RuntimeSrcDir=$(RepoRoot) /p:RuntimeConfig=$(Configuration)</_AOTBuildCommand>
+
+    <_AOTBuildCommand>$(_AOTBuildCommand) /p:RunAOTCompilation=$(RunAOTCompilation)</_AOTBuildCommand>
+    <_AOTBuildCommand>$(_AOTBuildCommand) &amp;&amp; cd wasm_build/AppBundle</_AOTBuildCommand>
+
+    <RunScriptCommand Condition="'$(RunScriptCommand)' == ''">$(_AOTBuildCommand)</RunScriptCommand>
+    <RunScriptCommand Condition="'$(RunScriptCommand)' != ''">$(_AOTBuildCommand) &amp;&amp; $(RunScriptCommand)</RunScriptCommand>
   </PropertyGroup>
 
   <PropertyGroup Condition="'$(UseDefaultBlazorWASMFeatureSwitches)' == 'true'">
     <EventSourceSupport>false</EventSourceSupport>
-    <UseSystemResourceKeys>true</UseSystemResourceKeys>
+    <UseSystemResourceKeys>false</UseSystemResourceKeys>
     <EnableUnsafeUTF7Encoding>false</EnableUnsafeUTF7Encoding>
     <HttpActivityPropagationSupport>false</HttpActivityPropagationSupport>
 
     <!-- we want to default to what Blazor has, except if we are building in Debug config -->
-    <DebuggerSupport Condition="'$(Configuration)' != 'Debug'">false</DebuggerSupport>
+    <DebuggerSupport Condition="'$(DebuggerSupport)' == '' and '$(Configuration)' != 'Debug'">false</DebuggerSupport>
   </PropertyGroup>
 
   <!-- Don't include InTree.props here, because the test projects themselves can set the target* properties -->
-  <Import Project="$(MonoProjectRoot)\wasm\build\WasmApp.props" />
-  <Import Project="$(MonoProjectRoot)\wasm\build\WasmApp.InTree.targets" />
+  <Import Project="$(MonoProjectRoot)\wasm\build\WasmApp.props"
+          Condition="'$(BuildAOTTestsOn)' == 'local'" />
+  <Import Project="$(MonoProjectRoot)\wasm\build\WasmApp.InTree.targets"
+          Condition="'$(BuildAOTTestsOn)' == 'local'" />
+
   <PropertyGroup>
       <WasmBuildAppDependsOn>PrepareForWasmBuildApp;$(WasmBuildAppDependsOn)</WasmBuildAppDependsOn>
-      <EmSdkDir>$([MSBuild]::NormalizeDirectory('$(RepoRoot)', 'src', 'mono', 'wasm', 'emsdk'))</EmSdkDir>
+      <EmSdkDirForHelixPayload>$([MSBuild]::NormalizeDirectory('$(RepoRoot)', 'src', 'mono', 'wasm', 'emsdk'))</EmSdkDirForHelixPayload>
+
+      <BundleTestWasmAppDependsOn Condition="'$(BuildAOTTestsOn)' == 'local'">WasmBuildApp</BundleTestWasmAppDependsOn>
+      <BundleTestWasmAppDependsOn Condition="'$(BuildAOTTestsOn)' == 'helix'">StageEmSdkForHelix</BundleTestWasmAppDependsOn>
+
+      <BundleTestWasmAppDependsOn Condition="'$(BuildAOTTestsOnHelix)' == 'true'">$(BundleTestWasmAppDependsOn);_BundleAOTTestWasmAppForHelix</BundleTestWasmAppDependsOn>
   </PropertyGroup>
 
-  <Target Name="BundleTestWasmApp" DependsOnTargets="WasmBuildApp;StageEmSdkForHelix" />
+  <Target Name="BundleTestWasmApp" DependsOnTargets="$(BundleTestWasmAppDependsOn)" />
+
+  <UsingTask Condition="'$(BuildAOTTestsOnHelix)' == 'true'"
+             TaskName="Microsoft.WebAssembly.Build.Tasks.GenerateAOTProps"
+             AssemblyFile="$(WasmBuildTasksAssemblyPath)" />
+
+  <Target Name="_BundleAOTTestWasmAppForHelix" DependsOnTargets="PrepareForWasmBuildApp">
+    <ItemGroup>
+      <BundleFiles Include="$(WasmMainJSPath)"                  TargetDir="publish" />
+      <BundleFiles Include="@(WasmSatelliteAssemblies)"         TargetDir="publish/%(WasmSatelliteAssemblies.CultureName)" />
+      <BundleFiles Include="@(WasmAssembliesToBundle)"          TargetDir="publish" />
+
+      <BundleFiles Include="$(MonoProjectRoot)\wasm\data\aot-tests\*" TargetDir="publish" />
+    </ItemGroup>
+
+    <ItemGroup Condition="'$(DebuggerSupport)' == 'true'">
+      <!-- Add any pdb files, if available -->
+      <_BundlePdbFiles Include="$([System.IO.Path]::ChangeExtension('%(WasmAssembliesToBundle.Identity)', '.pdb'))" />
+      <BundleFiles Include="@(_BundlePdbFiles)" TargetDir="publish" Condition="Exists(%(_BundlePdbFiles.Identity))" />
+    </ItemGroup>
+
+    <!-- To recreate the original project on helix, we need to set the wasm properties also, same as the
+         library test project. Eg. $(InvariantGlobalization) -->
+    <ItemGroup>
+      <_WasmPropertyNames Include="InvariantGlobalization" />
+      <_WasmPropertyNames Include="AOTMode" />
+      <_WasmPropertyNames Include="WasmDebugLevel" />
+      <_WasmPropertyNames Include="WasmBuildNative" />
+      <_WasmPropertyNames Include="_WasmDevel" />
+      <_WasmPropertyNames Include="WasmLinkIcalls" />
+      <_WasmPropertyNames Include="WasmDedup" />
+      <_WasmPropertyNames Include="IncludeSatelliteAssembliesInVFS" />
+
+      <_WasmPropertiesToPass
+        Include="$(%(_WasmPropertyNames.Identity))"
+        Name="%(_WasmPropertyNames.Identity)"
+        ConditionToUse="%(_WasmPropertyNames.ConditionToUse)" />
+
+      <_WasmVFSFilesToCopy Include="@(WasmFilesToIncludeInFileSystem)" />
+      <_WasmVFSFilesToCopy TargetPath="%(FileName)%(Extension)" Condition="'%(TargetPath)' == ''" />
+    </ItemGroup>
+
+    <!-- This file gets imported by the project file on helix -->
+    <GenerateAOTProps
+        Properties="@(_WasmPropertiesToPass)"
+        OutputFile="$(BundleDir)publish\AOTTestProjectForHelix.props" />
+
+    <Copy SourceFiles="@(BundleFiles)"         DestinationFolder="$(BundleDir)%(TargetDir)" />
+    <Copy SourceFiles="@(_WasmVFSFilesToCopy)" DestinationFiles="$(BundleDir)\extraFiles\%(_WasmVFSFilesToCopy.TargetPath)" />
+  </Target>
 
   <!-- CI has emscripten provisioned in $(EMSDK_PATH) as `/usr/local/emscripten`. Because helix tasks will
    attempt to write a .payload file, we cannot use $(EMSDK_PATH) to package emsdk as a helix correlation 
    payload. Instead, we copy over the files to a new directory `src/mono/wasm/emsdk` and use that. -->
-  <Target Name="StageEmSdkForHelix" Condition="'$(Scenario)' == 'BuildWasmApps' and '$(ContinuousIntegrationBuild)' == 'true' and !Exists($(EmSdkDir))">
-    <Error Condition="!Exists($(EMSDK_PATH))" Text="Could not find emscripten sdk in $(EmSdkDir) or in EMSDK_PATH=$(EMSDK_PATH)" />
+  <Target Name="StageEmSdkForHelix" Condition="'$(EmSdkDirForHelixPayload)' == '' or !Exists($(EmSdkDirForHelixPayload))">
+    <Error Condition="'$(EMSDK_PATH)' == '' or !Exists($(EMSDK_PATH))" Text="Could not find emscripten sdk in $(EmSdkDirForHelixPayload) or in EMSDK_PATH=$(EMSDK_PATH)" />
 
     <ItemGroup>
       <EmSdkFiles Include="$(EMSDK_PATH)\**\*" Exclude="$(EMSDK_PATH)\.git\**\*" />
     </ItemGroup>
 
-    <MakeDir Directories="$(EmSdkDir)" />
-    <Copy SourceFiles="@(EmSdkFiles)" DestinationFolder="$(EmSdkDir)\%(RecursiveDir)" />
+    <MakeDir Directories="$(EmSdkDirForHelixPayload)" />
+    <Copy SourceFiles="@(EmSdkFiles)" DestinationFolder="$(EmSdkDirForHelixPayload)\%(RecursiveDir)" />
   </Target>
 
   <Target Name="PrepareForWasmBuildApp">
@@ -74,17 +153,30 @@
 
     <ItemGroup>
       <WasmSatelliteAssemblies Include="$(PublishDir)*\*.resources.dll" />
-      <WasmSatelliteAssemblies>
-        <CultureName>$([System.IO.Directory]::GetParent('%(Identity)').Name)</CultureName>
-      </WasmSatelliteAssemblies>
+      <WasmSatelliteAssemblies CultureName="$([System.IO.Directory]::GetParent('%(Identity)').Name)" />
 
       <WasmAssembliesToBundle Include="$(PublishDir)\*.dll"/>
 
       <WasmFilesToIncludeInFileSystem Include="@(ContentWithTargetPath)" />
-      <WasmFilesToIncludeInFileSystem Include="@(ReferenceCopyLocalPaths)" Condition="'%(ReferenceCopyLocalPaths.BuildReference)' == 'true' and !$([System.String]::new('%(ReferenceCopyLocalPaths.Identity)').EndsWith('.resources.dll'))" />
-      <WasmFilesToIncludeInFileSystem Include="@(WasmSatelliteAssemblies)" TargetPath="%(WasmSatelliteAssemblies.CultureName)\%(WasmSatelliteAssemblies.Filename)%(WasmSatelliteAssemblies.Extension)" />
+      <WasmFilesToIncludeInFileSystem
+              Include="@(WasmSatelliteAssemblies)"
+              TargetPath="%(WasmSatelliteAssemblies.CultureName)\%(WasmSatelliteAssemblies.FileName)%(WasmSatelliteAssemblies.Extension)"
+              Condition="'$(IncludeSatelliteAssembliesInVFS)' == 'true'" />
+
+      <_CopyLocalPaths
+              Include="@(PublishItemsOutputGroupOutputs)"
+              Condition="'%(PublishItemsOutputGroupOutputs.BuildReference)' == 'true' and
+                         !$([System.String]::new('%(PublishItemsOutputGroupOutputs.Identity)').EndsWith('.resources.dll'))" />
+
+      <_CopyLocalPaths TargetPath="%(_CopyLocalPaths.RelativePath)" Condition="'%(_CopyLocalPaths.RelativePath)' != ''" />
+      <_CopyLocalPaths TargetPath="%(FileName)%(Extension)"         Condition="'%(_CopyLocalPaths.RelativePath)' == ''" />
+      <WasmFilesToIncludeInFileSystem Include="@(_CopyLocalPaths)" />
+
       <!-- Include files specified by test projects from publish dir -->
-      <WasmFilesToIncludeInFileSystem Include="@(WasmFilesToIncludeFromPublishDir -> '$(PublishDir)%(Identity)')" />
+      <WasmFilesToIncludeInFileSystem
+              Include="$(PublishDir)%(WasmFilesToIncludeFromPublishDir.Identity)"
+              TargetPath="%(WasmFilesToIncludeFromPublishDir.Identity)"
+              Condition="'%(WasmFilesToIncludeFromPublishDir.Identity)' != ''" />
     </ItemGroup>
   </Target>
 

src/libraries/Microsoft.CSharp/tests/Microsoft.CSharp.Tests.csproj

@@ -7,6 +7,8 @@
     "Operator '-' cannot be applied to operands of type 'ushort' and 'EnumArithmeticTests.UInt16Enum'"
     -->
     <Features>$(Features.Replace('strict', '')</Features>
+
+    <DebuggerSupport Condition="'$(DebuggerSupport)' == '' and '$(TargetOS)' == 'Browser'">true</DebuggerSupport>
   </PropertyGroup>
   <ItemGroup>
     <Compile Include="AccessTests.cs" />

src/libraries/System.Collections.Concurrent/tests/System.Collections.Concurrent.Tests.csproj

@@ -3,6 +3,7 @@
     <TestRuntime>true</TestRuntime>
     <IncludeRemoteExecutor>true</IncludeRemoteExecutor>
     <TargetFrameworks>$(NetCoreAppCurrent)</TargetFrameworks>
+    <DebuggerSupport Condition="'$(DebuggerSupport)' == '' and '$(TargetOS)' == 'Browser'">true</DebuggerSupport>
   </PropertyGroup>
   <ItemGroup>
     <Compile Include="$(CoreLibSharedDir)System\Collections\Concurrent\IProducerConsumerCollectionDebugView.cs"
@@ -70,4 +71,4 @@
     <Compile Include="$(CommonTestPath)System\Collections\IEnumerable.Generic.Serialization.Tests.cs"
              Link="Common\System\Collections\IEnumerable.Generic.Serialization.Tests.cs" />
   </ItemGroup>
-</Project>
+</Project>

src/libraries/System.Collections.Immutable/tests/System.Collections.Immutable.Tests.csproj

@@ -2,6 +2,7 @@
   <PropertyGroup>
     <NoWarn>0436</NoWarn>
     <TargetFrameworks>$(NetCoreAppCurrent);net461</TargetFrameworks>
+    <DebuggerSupport Condition="'$(DebuggerSupport)' == '' and '$(TargetOS)' == 'Browser'">true</DebuggerSupport>
   </PropertyGroup>
   <ItemGroup>
     <Compile Include="$(CommonTestPath)System\Collections\DictionaryExtensions.cs" Condition="'$(TargetFramework)' == 'net461'"

src/libraries/System.Collections.NonGeneric/tests/System.Collections.NonGeneric.Tests.csproj

@@ -2,6 +2,7 @@
   <PropertyGroup>
     <IncludeRemoteExecutor>true</IncludeRemoteExecutor>
     <TargetFrameworks>$(NetCoreAppCurrent)</TargetFrameworks>
+    <DebuggerSupport Condition="'$(DebuggerSupport)' == '' and '$(TargetOS)' == 'Browser'">true</DebuggerSupport>
   </PropertyGroup>
   <ItemGroup>
     <!-- Common Collections tests -->

src/libraries/System.Collections/tests/System.Collections.Tests.csproj

@@ -2,6 +2,7 @@
   <PropertyGroup>
     <TargetFrameworks>$(NetCoreAppCurrent)</TargetFrameworks>
     <TestRuntime>true</TestRuntime>
+    <DebuggerSupport Condition="'$(DebuggerSupport)' == '' and '$(TargetOS)' == 'Browser'">true</DebuggerSupport>
   </PropertyGroup>
   <ItemGroup>
     <!-- Common Collections tests -->