Add L0 test for work directory validation failure path

[Copilot]

Addresses review feedback requesting test coverage for the work directory validation added in #4227. The validation code (Runner.cs:410-423) returns TerminatedError when the work directory cannot be created or accessed, but lacked test coverage for this failure path.

Changes

• Added RunCommand_ShouldReturnTerminatedError_WhenWorkDirCreationFails test in Test/L0/Listener/RunnerL0.cs
  • Simulates directory creation failure by placing a blocking file at the target path
  • Verifies runner returns Constants.Runner.ReturnCode.TerminatedError
  • Includes proper cleanup in finally block

The test exercises this code path:

try
{
    Directory.CreateDirectory(workDirectory);
    IOUtil.ValidateExecutePermission(workDirectory);
}
catch (Exception ex)
{
    Trace.Error(ex);
    _term.WriteError($"Fail to create and validate runner's work directory '{workDirectory}'.");
    return Constants.Runner.ReturnCode.TerminatedError;
}

---

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[Copilot]

Just as a heads up, I was blocked by some firewall rules while working on your feedback. Expand below for details.

Warning

Firewall rules blocked me from connecting to one or more addresses (expand for details)

I tried to connect to the following addresses, but was blocked by firewall rules:

• https://api.github.com/repos/TingluoHuang/REDACTED_L0/tarball/CompositeBasic
  • Triggering command: /home/REDACTED/work/REDACTED/REDACTED/_dotnetsdk/8.0.417/dotnet /home/REDACTED/work/REDACTED/REDACTED/_dotnetsdk/8.0.417/dotnet exec --runtimeconfig /home/REDACTED/work/REDACTED/REDACTED/src/Test/bin/Debug/net8.0/Test.runtimeconfig.json --depsfile /home/REDACTED/work/REDACTED/REDACTED/src/Test/bin/Debug/net8.0/Test.deps.json /home/REDACTED/work/REDACTED/REDACTED/src/Test/bin/Debug/net8.0/testhost.dll --port 36571 --endpoint 127.0.0.1:036571 --role client --parentprocessid 6213 --telemetryoptedin false (http block)
• https://api.github.com/repos/TingluoHuang/REDACTED_L0/tarball/CompositeLimit
  • Triggering command: /home/REDACTED/work/REDACTED/REDACTED/_dotnetsdk/8.0.417/dotnet /home/REDACTED/work/REDACTED/REDACTED/_dotnetsdk/8.0.417/dotnet exec --runtimeconfig /home/REDACTED/work/REDACTED/REDACTED/src/Test/bin/Debug/net8.0/Test.runtimeconfig.json --depsfile /home/REDACTED/work/REDACTED/REDACTED/src/Test/bin/Debug/net8.0/Test.deps.json /home/REDACTED/work/REDACTED/REDACTED/src/Test/bin/Debug/net8.0/testhost.dll --port 36571 --endpoint 127.0.0.1:036571 --role client --parentprocessid 6213 --telemetryoptedin false (http block)
• https://api.github.com/repos/TingluoHuang/REDACTED_L0/tarball/RepositoryActionWithActionYamlFile_DockerHubImage
  • Triggering command: /home/REDACTED/work/REDACTED/REDACTED/_dotnetsdk/8.0.417/dotnet /home/REDACTED/work/REDACTED/REDACTED/_dotnetsdk/8.0.417/dotnet exec --runtimeconfig /home/REDACTED/work/REDACTED/REDACTED/src/Test/bin/Debug/net8.0/Test.runtimeconfig.json --depsfile /home/REDACTED/work/REDACTED/REDACTED/src/Test/bin/Debug/net8.0/Test.deps.json /home/REDACTED/work/REDACTED/REDACTED/src/Test/bin/Debug/net8.0/testhost.dll --port 36571 --endpoint 127.0.0.1:036571 --role client --parentprocessid 6213 --telemetryoptedin false (http block)
• https://api.github.com/repos/TingluoHuang/REDACTED_L0/tarball/RepositoryActionWithActionfile_DockerHubImage
  • Triggering command: /home/REDACTED/work/REDACTED/REDACTED/_dotnetsdk/8.0.417/dotnet /home/REDACTED/work/REDACTED/REDACTED/_dotnetsdk/8.0.417/dotnet exec --runtimeconfig /home/REDACTED/work/REDACTED/REDACTED/src/Test/bin/Debug/net8.0/Test.runtimeconfig.json --depsfile /home/REDACTED/work/REDACTED/REDACTED/src/Test/bin/Debug/net8.0/Test.deps.json /home/REDACTED/work/REDACTED/REDACTED/src/Test/bin/Debug/net8.0/testhost.dll --port 36571 --endpoint 127.0.0.1:036571 --role client --parentprocessid 6213 --telemetryoptedin false (http block)
• https://api.github.com/repos/TingluoHuang/REDACTED_L0/tarball/RepositoryActionWithInvalidWrapperActionfile_Node
  • Triggering command: /home/REDACTED/work/REDACTED/REDACTED/_dotnetsdk/8.0.417/dotnet /home/REDACTED/work/REDACTED/REDACTED/_dotnetsdk/8.0.417/dotnet exec --runtimeconfig /home/REDACTED/work/REDACTED/REDACTED/src/Test/bin/Debug/net8.0/Test.runtimeconfig.json --depsfile /home/REDACTED/work/REDACTED/REDACTED/src/Test/bin/Debug/net8.0/Test.deps.json /home/REDACTED/work/REDACTED/REDACTED/src/Test/bin/Debug/net8.0/testhost.dll --port 36571 --endpoint 127.0.0.1:036571 --role client --parentprocessid 6213 --telemetryoptedin false (http block)
• https://api.github.com/repos/TingluoHuang/REDACTED_L0/tarball/RepositoryActionWithWrapperActionfile_Node
  • Triggering command: /home/REDACTED/work/REDACTED/REDACTED/_dotnetsdk/8.0.417/dotnet /home/REDACTED/work/REDACTED/REDACTED/_dotnetsdk/8.0.417/dotnet exec --runtimeconfig /home/REDACTED/work/REDACTED/REDACTED/src/Test/bin/Debug/net8.0/Test.runtimeconfig.json --depsfile /home/REDACTED/work/REDACTED/REDACTED/src/Test/bin/Debug/net8.0/Test.deps.json /home/REDACTED/work/REDACTED/REDACTED/src/Test/bin/Debug/net8.0/testhost.dll --port 36571 --endpoint 127.0.0.1:036571 --role client --parentprocessid 6213 --telemetryoptedin false (http block)
• https://api.github.com/repos/TingluoHuang/REDACTED_L0/tarball/repositoryactionwithactionfileanddockerfile
  • Triggering command: /home/REDACTED/work/REDACTED/REDACTED/_dotnetsdk/8.0.417/dotnet /home/REDACTED/work/REDACTED/REDACTED/_dotnetsdk/8.0.417/dotnet exec --runtimeconfig /home/REDACTED/work/REDACTED/REDACTED/src/Test/bin/Debug/net8.0/Test.runtimeconfig.json --depsfile /home/REDACTED/work/REDACTED/REDACTED/src/Test/bin/Debug/net8.0/Test.deps.json /home/REDACTED/work/REDACTED/REDACTED/src/Test/bin/Debug/net8.0/testhost.dll --port 36571 --endpoint 127.0.0.1:036571 --role client --parentprocessid 6213 --telemetryoptedin false (http block)
• https://api.github.com/repos/TingluoHuang/REDACTED_L0/tarball/repositoryactionwithdockerfile
  • Triggering command: /home/REDACTED/work/REDACTED/REDACTED/_dotnetsdk/8.0.417/dotnet /home/REDACTED/work/REDACTED/REDACTED/_dotnetsdk/8.0.417/dotnet exec --runtimeconfig /home/REDACTED/work/REDACTED/REDACTED/src/Test/bin/Debug/net8.0/Test.runtimeconfig.json --depsfile /home/REDACTED/work/REDACTED/REDACTED/src/Test/bin/Debug/net8.0/Test.deps.json /home/REDACTED/work/REDACTED/REDACTED/src/Test/bin/Debug/net8.0/testhost.dll --port 36571 --endpoint 127.0.0.1:036571 --role client --parentprocessid 6213 --telemetryoptedin false (http block)
• https://api.github.com/repos/actions/download-artifact/tarball/master
  • Triggering command: /home/REDACTED/work/REDACTED/REDACTED/_dotnetsdk/8.0.417/dotnet /home/REDACTED/work/REDACTED/REDACTED/_dotnetsdk/8.0.417/dotnet exec --runtimeconfig /home/REDACTED/work/REDACTED/REDACTED/src/Test/bin/Debug/net8.0/Test.runtimeconfig.json --depsfile /home/REDACTED/work/REDACTED/REDACTED/src/Test/bin/Debug/net8.0/Test.deps.json /home/REDACTED/work/REDACTED/REDACTED/src/Test/bin/Debug/net8.0/testhost.dll --port 36571 --endpoint 127.0.0.1:036571 --role client --parentprocessid 6213 --telemetryoptedin false (http block)
• https://api.github.com/repos/actions/setup-node/tarball/v1
  • Triggering command: /home/REDACTED/work/REDACTED/REDACTED/_dotnetsdk/8.0.417/dotnet /home/REDACTED/work/REDACTED/REDACTED/_dotnetsdk/8.0.417/dotnet exec --runtimeconfig /home/REDACTED/work/REDACTED/REDACTED/src/Test/bin/Debug/net8.0/Test.runtimeconfig.json --depsfile /home/REDACTED/work/REDACTED/REDACTED/src/Test/bin/Debug/net8.0/Test.deps.json /home/REDACTED/work/REDACTED/REDACTED/src/Test/bin/Debug/net8.0/testhost.dll --port 36571 --endpoint 127.0.0.1:036571 --role client --parentprocessid 6213 --telemetryoptedin false (http block)

If you need me to access, download, or install something from one of these locations, you can either:

• Configure Actions setup steps to set up my environment, which run before the firewall is enabled
• Add the appropriate URLs or hosts to the custom allowlist in this repository's Copilot coding agent settings (admins only)