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ADR 0010: Govern autofix behavior with safe defaults and plugin-level kill switches

  • Status: Accepted
  • Date: 2026-02-28

Context​

This plugin includes migration rules where some transformations are fully safe while others are context-sensitive.

The codebase already implements runtime controls in settings.typefest and wraps rule contexts to strip fix callbacks when global autofixes are disabled.

Relevant implementation points include:

  • settings.typefest.disableAllAutofixes
  • settings.typefest.disableImportInsertionFixes
  • createContextWithoutAutofixes(...) in src/_internal/typed-rule.ts
  • parsed/memoized settings in src/_internal/plugin-settings.ts

Decision​

Adopt a formal autofix governance model:

  1. Rules should only emit fix when safety is deterministic.
  2. Rules should emit suggest for behavior-sensitive migrations.
  3. Global settings can suppress autofixes at runtime:
    • disableAllAutofixes removes all fix callbacks,
    • disableImportInsertionFixes disables import-insertion helpers.

Rationale​

  1. Operational safety: large migrations need a hard stop mechanism for automated rewrites.
  2. Predictable rollout: teams can start with diagnostics/suggestions before enabling broad fixing.
  3. Centralized control: settings-based suppression avoids rule-by-rule ad hoc toggles.

Consequences​

  • Fix behavior is intentionally policy-driven, not purely rule-local.
  • Rule authors must classify fixes as deterministic (fix) vs contextual (suggest).
  • Migration playbooks can use settings to stage risk and reduce churn.

Revisit Triggers​

Re-evaluate if:

  • ESLint introduces stronger first-class fix governance primitives,
  • the plugin requires finer-grained per-rule fix policy controls,
  • or contributors report current kill-switch granularity as insufficient.