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

[github-actions]

Apply moderate, tasteful functional/immutability improvements to the pkg/cli package to eliminate unnecessary mutable state and make data transformations more declarative.

Round-Robin Progress: First package processed. Next run will process pkg/cli/fileutil.

Summary of Changes

1. Immutability / Functional Initialization — compile_config.go

Replaced imperative nested loop initialization in sanitizeValidationResults with sliceutil.Map, and extracted a pure helper function sanitizeCompileValidationError.

Before:

sanitized := make([]ValidationResult, len(results))
for i, result := range results {
    sanitized[i] = ValidationResult{
        ...
        Errors:   make([]CompileValidationError, len(result.Errors)),
        Warnings: make([]CompileValidationError, len(result.Warnings)),
    }
    for j, err := range result.Errors {
        sanitized[i].Errors[j] = CompileValidationError{...}
    }
    for j, warn := range result.Warnings {
        sanitized[i].Warnings[j] = CompileValidationError{...}
    }
}
return sanitized

After:

return sliceutil.Map(results, func(result ValidationResult) ValidationResult {
    return ValidationResult{
        ...
        Errors:   sliceutil.Map(result.Errors, sanitizeCompileValidationError),
        Warnings: sliceutil.Map(result.Warnings, sanitizeCompileValidationError),
    }
})

// Pure helper function - same input always gives same output
func sanitizeCompileValidationError(err CompileValidationError) CompileValidationError {
    return CompileValidationError{
        Type:    err.Type,
        Message: stringutil.SanitizeErrorMessage(err.Message),
        Line:    err.Line,
    }
}

2. Transformative Operation — audit_report.go

Replaced var jobs []JobData + append loop with sliceutil.Map for the job data building in buildAuditData.

Before:

var jobs []JobData
for _, jobDetail := range processedRun.JobDetails {
    job := JobData{...}
    if jobDetail.Duration > 0 {
        job.Duration = timeutil.FormatDuration(jobDetail.Duration)
    }
    jobs = append(jobs, job)
}

After:

jobs := sliceutil.Map(processedRun.JobDetails, func(jobDetail JobInfoWithDuration) JobData {
    job := JobData{...}
    if jobDetail.Duration > 0 {
        job.Duration = timeutil.FormatDuration(jobDetail.Duration)
    }
    return job
})

3. Transformative Operation — audit_report_analysis.go

Replaced var failedJobs []string + conditional append loop with sliceutil.FilterMap in generateFailureAnalysis.

Before:

var failedJobs []string
for _, job := range processedRun.JobDetails {
    if job.Conclusion == "failure" || job.Conclusion == "timed_out" || job.Conclusion == "cancelled" {
        failedJobs = append(failedJobs, job.Name)
    }
}

After:

failedJobs := sliceutil.FilterMap(
    processedRun.JobDetails,
    func(job JobInfoWithDuration) bool {
        return job.Conclusion == "failure" || job.Conclusion == "timed_out" || job.Conclusion == "cancelled"
    },
    func(job JobInfoWithDuration) string { return job.Name },
)

Benefits

• Immutability: 3 mutable intermediate variables eliminated
• Clarity: Data transformation intent is immediately clear from the functional composition
• Purity: Extracted sanitizeCompileValidationError as a pure function (testable in isolation)
• Consistency: Uses existing sliceutil.Map/sliceutil.FilterMap utilities already in the codebase

Testing

• ✅ All existing tests pass (TestGenerateFindings, TestGenerateRecommendations, TestGenerateFailureAnalysis, TestBuildAuditData*)
• ✅ go vet ./pkg/cli/ clean
• ✅ make fmt clean
• ✅ No behavioral changes — functionality is identical

References:

• §22175708784

AI generated by Functional Pragmatist

• expires on Feb 20, 2026, 9:31 AM UTC

[pelikhan]

@copilot merge main

[Copilot]

@pelikhan I've opened a new pull request, #16812, to work on those changes. Once the pull request is ready, I'll request review from you.

[Copilot]

Pull request overview

This PR mixes two unrelated concerns: functional programming improvements to pkg/cli and Playwright domain support for pkg/workflow. The PR description only mentions the functional programming changes but omits significant changes including Playwright domain support, workflow lock file updates, action pin removals, and documentation additions.

Changes:

• Refactored three functions in pkg/cli to use sliceutil.Map and sliceutil.FilterMap for more declarative data transformations
• Added Playwright ecosystem domain support to automatically allow required domains when Playwright tool is configured
• Removed 6 unused action pin entries and updated stale-repos action SHA

Reviewed changes

Copilot reviewed 11 out of 11 changed files in this pull request and generated 2 comments.

Show a summary per file

File	Description
pkg/cli/compile_config.go	Refactored sanitizeValidationResults to use sliceutil.Map and extracted pure helper sanitizeCompileValidationError
pkg/cli/audit_report.go	Replaced imperative loop with sliceutil.Map for building job data
pkg/cli/audit_report_analysis.go	Replaced filter+append pattern with sliceutil.FilterMap for collecting failed job names
pkg/workflow/domains.go	Added PlaywrightDomains constant and extractPlaywrightDomains function to support Playwright browser downloads
pkg/workflow/http_mcp_domains_test.go	Added comprehensive test coverage for Playwright domain extraction
.github/workflows/stale-repo-identifier.lock.yml	Updated stale-repos action SHA with mismatched version comment
.github/workflows/slide-deck-maintainer.lock.yml	Added Playwright domains to allow-domains list
.github/workflows/docs-noob-tester.lock.yml	Added Playwright domains to allow-domains list
pkg/workflow/data/action_pins.json	Removed 6 unused action pin entries (stale-repos@v3.0.2, haskell-actions/setup@v2.10.3, oven-sh/setup-bun@v2.1.2, ruby/setup-ruby@v1.288.0, super-linter/super-linter@v8.2.1)
.github/aw/actions-lock.json	Removed same 6 unused action pin entries
docs/src/content/docs/reference/glossary.md	Added Playground glossary entry

---

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[Copilot]

Major discrepancy between PR description and actual changes

The PR title and description claim this PR improves "pkg/cli functional/immutability patterns", but the majority of changes are unrelated to this stated purpose:

1. pkg/workflow changes (NOT mentioned in description):

   • New Playwright domain support in domains.go
   • New test cases in http_mcp_domains_test.go

2. Lock file changes (NOT mentioned in description):

   • Removal of 6 action pin entries in action_pins.json and actions-lock.json
   • SHA updates in workflow lock files
   • Playwright domain additions to workflow allow-lists

3. Documentation changes (NOT mentioned in description):

   • New Playground glossary entry

The PR description should accurately reflect all changes being made. Either:

• Split this into separate PRs (one for functional patterns, one for Playwright support)
• Update the PR description to accurately describe all changes included

[Copilot]

Inconsistent version reference in comment

The SHA is being changed from a21e55567b83cf3c3f3f9085d3038dc6cee02598 to 3477b6488008d9411aaf22a0924ec7c1f6a69980, but the comment still references "v3.0.2".

Looking at the action_pins.json file, the new SHA (3477b64...) corresponds to the github/stale-repos@v3 entry (not v3.0.2). The old v3.0.2 entry with SHA a21e555... is being removed from action_pins.json.

Either:

• The comment should be updated to # v3 to match the actual pin being used, or
• The SHA should use a different value if v3.0.2 is specifically needed

This mismatch could cause confusion about which version is actually being used.

Suggested change

	uses: github/stale-repos@3477b6488008d9411aaf22a0924ec7c1f6a69980 # v3.0.2
	uses: github/stale-repos@3477b6488008d9411aaf22a0924ec7c1f6a69980 # v3