Today we support two different test runners: xunit.console and VSTest. The former is used when invoking the test target dotnet msbuild /t:Test and when running on CI. The latter is used when using VS Test Explorer, F5, the dotnet msbuild /t:Run target or when invoking dotnet test. To leverage the new crash dump / hang dump features that @davidfowl is driving in partnership with the VSTest team (cc @nohwnd), we should switch to VSTest and remove xunit.console entirely.

This issue only tracks the libraries side for non-mobile and non-WASM configurations. Mobile and WASM use a different harness called xharness which is out-of-scope at the moment.

1. Remove xunit.console:

• https://github.com/dotnet/runtime/blob/master/eng/testing/xunit/xunit.console.targets
• https://github.com/dotnet/runtime/blob/master/eng/testing/xunit/xunit.targets#L17

2. Remove runner templates for non-mobile and non-wasm:

• https://github.com/dotnet/runtime/blob/master/eng/testing/RunnerTemplate.cmd
• https://github.com/dotnet/runtime/blob/master/eng/testing/RunnerTemplate.sh
• 85bfbfc#diff-e7bc39410f7a119e7adb69b17006c452
• https://github.com/dotnet/runtime/blob/master/eng/testing/tests.targets#L22-L25

3. Revert 85bfbfc#diff-e7bc39410f7a119e7adb69b17006c452

4. Condition the RunTemplate and Test target logic on TargetsMobile and WASM:

• https://github.com/dotnet/runtime/blob/master/eng/testing/tests.targets#L109-L112
• https://github.com/dotnet/runtime/blob/master/eng/testing/tests.targets#L40-L104

5. Use dotnet test in CI instead of RunTests.cmd/sh for non-mobile and non-wasm:

• runtime/src/libraries/sendtohelix.proj

  Lines 69 to 70 in 132be64

  	<HelixCommand Condition="'$(TargetOS)' == 'Windows_NT'">call RunTests.cmd --runtime-path %HELIX_CORRELATION_PAYLOAD%</HelixCommand>
  	<HelixCommand Condition="'$(TargetOS)' != 'Windows_NT'">./RunTests.sh --runtime-path "$HELIX_CORRELATION_PAYLOAD"</HelixCommand>

6. Fix failing tests (ie Microsoft.Extensions.DependencyModel.Tests) and make sure that code coverage works.

7. Optional: use dotnet publish instead of the ArchiveTests target:

• https://github.com/dotnet/runtime/blob/master/eng/testing/tests.targets#L27-L38

cc @Anipik @ericstj @safern