[fp-enhancer] Improve pkg/cli with functional patterns

[github-actions]

Functional/Immutability Enhancements - Package: pkg/cli

This PR applies moderate, tasteful functional/immutability techniques to the pkg/cli package to improve code clarity, safety, testability, and maintainability.

Round-Robin Progress: This is part of a systematic package-by-package refactoring. Next package to process: pkg/console

Note: Cache update attempted but gh-aw extension not available in this environment. Next run should start with pkg/console.

Summary of Changes

1. Immutability Improvements

• 1 variable converted from mutable to immutable initialization
• 1 slice pre-allocated instead of incremental building

Files affected:

• pkg/cli/actionlint.go - Pre-allocated slice for relative paths (lines 197-205)

2. Transformative Data Operations

• 2 imperative loops converted to functional transformations
• Applied existing sliceutil.FilterMap and sliceutil.Map utilities

Files affected:

• pkg/cli/actions_build_command.go - Replaced directory filtering loop with sliceutil.FilterMap (lines 140-143)
• pkg/cli/add_workflow_pr.go - Replaced workflow name extraction loop with sliceutil.Map (lines 85-87)

Benefits

• Safety: Pre-allocated slice eliminates unnecessary append operations and potential reallocation overhead
• Clarity: Functional transformations make intent explicit (filter-and-map vs imperative loop)
• Maintainability: Leverages existing sliceutil package for consistency
• Performance: Pre-allocation reduces memory allocation overhead for known-size slices

Principles Applied

1. Immutability First: Pre-allocate slices when size is known rather than building incrementally
2. Declarative Over Imperative: Use functional utilities to express "what" not "how"
3. Leverage Existing Utilities: Use sliceutil package functions for consistency
4. Pragmatic Balance: Changes improve clarity without dogmatic adherence

Testing

• ✅ All tests pass (TestParseAndDisplayActionlintOutput, TestGetActionDirectories)
• ✅ Test existence verified BEFORE refactoring (via code search)
• ✅ Formatting passes (make fmt)
• ✅ No behavioral changes - functionality is identical
• ✅ Manual diff review confirms only style improvements

Test output:

=== RUN   TestParseAndDisplayActionlintOutput
--- PASS: TestParseAndDisplayActionlintOutput (0.00s)
=== RUN   TestGetActionDirectories  
--- PASS: TestGetActionDirectories (0.00s)
PASS
ok      github.com/github/gh-aw/pkg/cli 0.021s

Review Focus

Please verify:

• Pre-allocation pattern in actionlint.go is appropriate
• sliceutil.FilterMap usage in actions_build_command.go improves clarity
• sliceutil.Map usage in add_workflow_pr.go is consistent with codebase style
• No unintended side effects or behavior changes

Examples

Before: Mutable slice building in actionlint.go

var relPaths []string
for _, lockFile := range lockFiles {
    relPath, err := filepath.Rel(gitRoot, lockFile)
    if err != nil {
        return fmt.Errorf("failed to get relative path for %s: %w", lockFile, err)
    }
    relPaths = append(relPaths, relPath)
}

After: Pre-allocated immutable initialization

relPaths := make([]string, len(lockFiles))
for i, lockFile := range lockFiles {
    relPath, err := filepath.Rel(gitRoot, lockFile)
    if err != nil {
        return fmt.Errorf("failed to get relative path for %s: %w", lockFile, err)
    }
    relPaths[i] = relPath
}

Before: Imperative directory filtering in actions_build_command.go

var dirs []string
for _, entry := range entries {
    if entry.IsDir() {
        dirs = append(dirs, entry.Name())
    }
}

After: Functional filter-and-map

dirs := sliceutil.FilterMap(entries,
    func(entry os.DirEntry) bool { return entry.IsDir() },
    func(entry os.DirEntry) string { return entry.Name() },
)

Before: Imperative workflow name extraction in add_workflow_pr.go

workflowNames := make([]string, len(workflows))
for i, wf := range workflows {
    workflowNames[i] = wf.WorkflowName
}

After: Functional map transformation

workflowNames := sliceutil.Map(workflows, func(wf *WorkflowSpec) string {
    return wf.WorkflowName
})

Impact

• 3 files modified with surgical, minimal changes
• ~15 lines of code replaced with clearer functional patterns
• Zero behavioral changes - all tests pass unchanged
• Consistent with existing codebase - uses existing sliceutil package

---

Automated by Functional Pragmatist - applying moderate functional/immutability techniques to pkg/cli

AI generated by Functional Pragmatist

• expires on Feb 11, 2026, 9:30 AM UTC

[github-actions]

🔍 PR Triage Results

Category: refactor | Risk: low | Priority: 32/100

Scores Breakdown

• Impact: 25/50 - Code quality improvement through functional patterns
• Urgency: 0/30 - Recent PR (3.0 hours old), no urgent need
• Quality: 7/20 - Draft status, reduced quality score, pending CI

📋 Recommended Action: batch_review

Rationale: Applies functional programming patterns to pkg/cli (pre-allocated slices, FilterMap). Low impact changes (~27 lines) but marked as draft.

Next Steps:

• Review functional pattern implementations
• Ensure no behavior changes
• Mark as ready for review when complete

---

Triaged by PR Triage Agent on 2026-02-10

AI generated by PR Triage Agent