[plan] Update workflow compiler to generate grouped shell redirects (SC2129)

[github-actions]

Objective

Modify the gh-aw workflow compiler to generate grouped shell redirects instead of individual redirects, eliminating 164 shellcheck SC2129 style warnings across all compiled workflows.

Context

From discussion #15009 - Actionlint/shellcheck reports 164 occurrences of SC2129 across all 149 workflows (49% of all findings). This is a style issue in compiler-generated code.

Current Pattern (Generated):

echo "line 1" >> "$GH_AW_PROMPT"
echo "line 2" >> "$GH_AW_PROMPT"
echo "line 3" >> "$GH_AW_PROMPT"

Desired Pattern:

{
  echo "line 1"
  echo "line 2"
  echo "line 3"
} >> "$GH_AW_PROMPT"

Approach

1. Locate the compiler code that generates shell scripts with redirects (likely in prompt construction or YAML generation phase)

   • Check pkg/workflow/compiler.go or pkg/workflow/compiler_yaml.go
   • Look for code generating multiple consecutive redirects to the same file/variable

2. Implement grouping logic:

   • Detect sequences of commands redirecting to the same file
   • Group them using brace syntax { ... }
   • Apply single redirect at the end

3. Handle edge cases:

   • Single redirects (don't group)
   • Mixed redirect types (> vs >>)
   • Redirects to different files
   • Preserve error handling behavior

4. Test the changes:

   • Recompile several workflows with make recompile
   • Verify generated .lock.yml files use grouped redirects
   • Run gh aw compile --actionlint to confirm SC2129 warnings eliminated
   • Run make test-unit to ensure tests pass
   • Test workflow execution to ensure behavior unchanged

Files to Modify

• pkg/workflow/compiler.go or pkg/workflow/compiler_yaml.go (compiler logic)
• Potentially add helper functions for grouping redirects
• Update tests if needed

Acceptance Criteria

• Compiler generates grouped redirects for consecutive commands targeting same file
• All 164 SC2129 warnings eliminated (verify with actionlint)
• Edge cases handled correctly (single redirects, mixed types)
• Unit tests pass (make test-unit)
• Sample workflows recompile and execute correctly
• Generated code is cleaner and more performant

AI generated by Plan Command for discussion #15009

• expires on Feb 14, 2026, 1:28 AM UTC