use TestDisableParallelization property to disable parallel test execution

[adamsitnik]

It's defined in:

runtime/eng/testing/runsettings.targets

Lines 30 to 42 in c66fa99

	<RunSettingsFileContent Condition="'$(TestDisableParallelization)' == 'true'">$(RunSettingsFileContent.Replace('$$MAXCPUCOUNT$$', '1'))</RunSettingsFileContent>
	<RunSettingsFileContent Condition="'$(TestDisableParallelization)' != 'true'">$(RunSettingsFileContent.Replace('$$MAXCPUCOUNT$$', '0'))</RunSettingsFileContent>
	<!-- Arm64 is currently not a known TargetPlatform value in VSTEST: https://github.com/microsoft/vstest/issues/2566 -->
	<RunSettingsFileContent Condition="'$(TargetArchitecture)' != 'arm64'">$(RunSettingsFileContent.Replace('$$TARGETPLATFORM$$', '<TargetPlatform>$(TargetArchitecture)</TargetPlatform>'))</RunSettingsFileContent>
	<RunSettingsFileContent Condition="'$(TargetArchitecture)' == 'arm64'">$(RunSettingsFileContent.Replace('$$TARGETPLATFORM$$', ''))</RunSettingsFileContent>
	<RunSettingsFileContent>$(RunSettingsFileContent.Replace('$$COVERAGE_INCLUDE$$', '$(CoverageIncludeFilter)')
	.Replace('$$COVERAGE_EXCLUDEBYFILE$$', '$(CoverageExcludeByFileFilter)')
	.Replace('$$COVERAGE_INCLUDEDIRECTORY$$', '$(CoverageIncludeDirectoryFilter)')
	.Replace('$$COVERAGE_ENABLED$$', '$([MSBuild]::ValueOrDefault('$(Coverage)', 'false'))')
	.Replace('$$DISABLEPARALLELIZATION$$', '$([MSBuild]::ValueOrDefault('$(TestDisableParallelization)', 'false'))')
	.Replace('$$DISABLEAPPDOMAIN$$', '$([MSBuild]::ValueOrDefault('$(TestDisableAppDomain)', 'false'))')
	.Replace('$$TESTCASEFILTER$$', '$(_testFilter)')
	.Replace('$$DOTNETHOSTPATH$$', '$(NetCoreAppCurrentTestHostPath)$([System.IO.Path]::GetFileName('$(DotNetTool)'))'))</RunSettingsFileContent>

and I've tested that it works as expected.

[ghost]

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Issue Details

---

It's defined in:

runtime/eng/testing/runsettings.targets

Lines 30 to 42 in c66fa99

	<RunSettingsFileContent Condition="'$(TestDisableParallelization)' == 'true'">$(RunSettingsFileContent.Replace('$$MAXCPUCOUNT$$', '1'))</RunSettingsFileContent>
	<RunSettingsFileContent Condition="'$(TestDisableParallelization)' != 'true'">$(RunSettingsFileContent.Replace('$$MAXCPUCOUNT$$', '0'))</RunSettingsFileContent>
	<!-- Arm64 is currently not a known TargetPlatform value in VSTEST: https://github.com/microsoft/vstest/issues/2566 -->
	<RunSettingsFileContent Condition="'$(TargetArchitecture)' != 'arm64'">$(RunSettingsFileContent.Replace('$$TARGETPLATFORM$$', '<TargetPlatform>$(TargetArchitecture)</TargetPlatform>'))</RunSettingsFileContent>
	<RunSettingsFileContent Condition="'$(TargetArchitecture)' == 'arm64'">$(RunSettingsFileContent.Replace('$$TARGETPLATFORM$$', ''))</RunSettingsFileContent>
	<RunSettingsFileContent>$(RunSettingsFileContent.Replace('$$COVERAGE_INCLUDE$$', '$(CoverageIncludeFilter)')
	.Replace('$$COVERAGE_EXCLUDEBYFILE$$', '$(CoverageExcludeByFileFilter)')
	.Replace('$$COVERAGE_INCLUDEDIRECTORY$$', '$(CoverageIncludeDirectoryFilter)')
	.Replace('$$COVERAGE_ENABLED$$', '$([MSBuild]::ValueOrDefault('$(Coverage)', 'false'))')
	.Replace('$$DISABLEPARALLELIZATION$$', '$([MSBuild]::ValueOrDefault('$(TestDisableParallelization)', 'false'))')
	.Replace('$$DISABLEAPPDOMAIN$$', '$([MSBuild]::ValueOrDefault('$(TestDisableAppDomain)', 'false'))')
	.Replace('$$TESTCASEFILTER$$', '$(_testFilter)')
	.Replace('$$DOTNETHOSTPATH$$', '$(NetCoreAppCurrentTestHostPath)$([System.IO.Path]::GetFileName('$(DotNetTool)'))'))</RunSettingsFileContent>

and I've tested that it works as expected.

Author:	adamsitnik
Assignees:	-
Labels:	area-Infrastructure-libraries
Milestone:	-

[jkotas]

I've tested that it works as expected.

Does it work as expected when running tests from command line or in the CI? The .runsettings file seems to be VS specific.

[adamsitnik]

Does it work as expected when running tests from command line or in the CI?

I was running it using the dotnet.cmd script:

.\dotnet.cmd build /t:Test .\src\libraries\System.IO.FileSystem.DriveInfo\tests\System.IO.FileSystem.DriveInfo.Tests.csproj  /p:Configuration=Release

Which I assume is used by the CI? I am going to run it using a global SDK and get back to you.

[adamsitnik]

It works both when using dotnet.cmd and a dotnet.exe from $PATH

[jkotas]

Ah ok, it is passed to XUnit on command line here:

runtime/eng/testing/xunit/xunit.console.targets

Line 18 in 57bfe47

<RunScriptCommand Condition="'$(TestDisableParallelization)' == 'true'">$(RunScriptCommand) -maxthreads 1</RunScriptCommand>

[jkotas]

But it is not obvious to me that the extra argument will be passed all the way through for mobile test targets (iOS/Android/browser) that encapsulate the test in an app.

I think the existing solution where the test spec is fully encapsulated in the test .dll is better.

[stephentoub]

I think the existing solution where the test spec is fully encapsulated in the test .dll is better.

+1. The less msbuild magic that might subtly be missed in various configurations, the better.

[adamsitnik]

@jkotas @stephentoub Thank you for your feedback. I am going to close the PR and just move src/libraries/System.Private.Xml/tests/Writers/XmlWriterApi/DisableParallelization.cs to some common folder and re-use it for System.IO.FileSystem.DriveInfo tests (#62134)