panicinlibrarycode: recognize sync.OnceValue/OnceFunc panic exemptions

[Copilot]

panicinlibrarycode only exempted sync.Once.Do(func(){...}) and missed equivalent Go 1.21+ lazy-init patterns (sync.OnceValue / sync.OnceFunc). That created a governance gap where exemption behavior depended on panic message text (BUG:) rather than call-site semantics.

• Analyzer exemption expansion

  • Generalized sync-once callback detection from Once.Do-only to all supported sync-once initializer forms.
  • Added selector extraction for call expressions (including indexed call forms) and symbol/package checks to ensure exemptions apply only to sync.OnceValue / sync.OnceFunc / (*sync.Once).Do.

• Behavioral consistency

  • Preserves existing Once.Do handling.
  • Aligns all sync-once lazy-init idioms under the same exemption rule, removing accidental reliance on panic string prefixes.

• Focused test coverage

  • Added analyzer testdata cases with panics inside:
    • sync.OnceValue(func() T { ... })
    • sync.OnceFunc(func() { ... })
  • These cases are intentionally non-BUG: panic messages to validate semantic exemption logic.

var onceValue = sync.OnceValue(func() int {
	panic("lazy init failure in sync.OnceValue") // should not be flagged
	return 0
})

var onceFunc = sync.OnceFunc(func() {
	panic("lazy init failure in sync.OnceFunc") // should not be flagged
})

• Fixes [deep-report] Fix panicinlibrarycode linter blind spot: sync.OnceValue/OnceFunc panics not exempted #48919

[Copilot]

Pull request overview

Extends the panic linter’s sync.Once exemption to Go 1.21 lazy-initialization helpers.

Changes:

• Recognizes sync.OnceValue and sync.OnceFunc callbacks.
• Adds selector and generic-call handling.
• Adds focused analyzer test cases.

Show a summary per file

File	Description
pkg/linters/panic-in-library-code/panic-in-library-code.go	Generalizes sync-once callback detection.
pkg/linters/panic-in-library-code/testdata/src/panicinlibrarycode/panicinlibrarycode.go	Tests OnceValue and OnceFunc exemptions.

Review details

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• Files reviewed: 2/2 changed files
• Comments generated: 1
• Review effort level: Medium

[github-actions]

Triage: bug (linter fix)

Risk: low | Priority: medium (score 48/100)

Breakdown: impact 20/50 (narrow linter-analyzer scope, 2 files) · urgency 15/30 (CI fully green) · quality 13/20 (good description, has test data, no reviews yet)

Recommended action: batch_review (group with other small low-risk lint/tooling PRs)

All CI checks passing. Small, well-scoped fix to panicinlibrarycode analyzer exemptions.

Generated by 🔧 PR Triage Agent · aut00 · 40.7 AIC · ⌖ 5.25 AIC · ⊞ 7.9K · ◷

[github-actions]

🎉 This pull request is included in a new release.

Release: v0.84.0