Summary

• isolate the Unix parent-exit watcher from inherited shell control variables
• prevent exported TMOUT from timing out the watcher's blocking read and killing healthy workflow steps
• add regression coverage for both inherited TMOUT and real parent-exit cleanup behavior

Related Issues

• Closes signal: killed #2253

Checklist

• Code style follows existing patterns
• Self-review completed
• Tests added or updated where needed
• Documentation updated or not required
• Local validation completed

Testing

• go test ./internal/cmn/cmdutil -run 'TestParentExitWatcher(IgnoresInheritedShellTimeout|TerminatesChildWhenParentExits)$' -count=1
• go test ./internal/cmn/cmdutil -count=1
• make test TEST_TARGET=./internal/cmn/cmdutil
• git diff --check
• patched CLI repro: TMOUT=3 with a sleep 5 DAG completed successfully instead of dying at 3 seconds

Summary by cubic

Isolates the Unix parent-exit watcher from inherited shell control variables to prevent TMOUT from aborting its blocking read and killing healthy steps. Adds regression tests for TMOUT inheritance and parent-exit cleanup. Closes #2253.

• Bug Fixes
  • Set a minimal env for the watcher (Env = ["PATH=/usr/bin:/bin"]) so shell vars like TMOUT don’t affect its blocking read.
  • Added external tests verifying the watcher ignores inherited TMOUT and still terminates the child when the parent exits.

^{Written for commit 162c532. Summary will update on new commits.}

Summary by CodeRabbit

• Bug Fixes

  • Fixed parent exit watcher stability on Unix systems by preventing shell environment variables from interfering with the watcher process.

• Tests

  • Added test coverage for parent exit watcher behavior on Unix platforms, including shell timeout handling and child process termination scenarios.