react-doctor/prefer-stable-empty-fallback
Hoist a module-level const EMPTY = [] (or {}) and use it as the || / ?? fallback so the memoised child sees a stable reference
- Status
- Active
- Category
- Performance
- Assessment
- Evidence-required risk
- Required evidence
- source code, runtime behavior, measurement
- Default configuration
- Enabled
- Default severity
- warn
Show technical metadata
- Scope
- All supported frameworks
- Active when
- always
- Disabled when
- react-compiler
- Requirements
- react
- Tags
- react-jsx-only, test-noise
- Priority
- 38 (P3)
- Source
- oxlint-plugin-react-doctor
- Rule set
- oxlint-plugin-react-doctor 0.9.3 (prompt schema 2)
Validation prompt
Confirm the detector match and collect the required evidence before deciding whether an edit is warranted.
Fires on an empty array or object fallback passed to a same-file component that the detector's HOC registry classifies as memoized. Confirm the recipient actually performs prop memoization or otherwise relies on reference identity. React.lazy only defers loading and does not shallow-compare props, so a component wrapped only in lazy or React.lazy is a false positive unless the loaded component is independently memoized. Also suppress other registry wrappers whose installed implementation does not memoize props.
Evidence boundary
The diagnostic proves only that the detector’s modeled source pattern matched. It does not prove runtime impact, product intent, rendered failure, or that one remediation is correct.
Establish the environment, repository policy, exceptions, and required rendered or runtime evidence before deciding the occurrence.
Record one outcome:
- Confirmed failure: The required evidence establishes the violation.
- Rejected: A documented exception or false-positive predicate applies.
- Needs evidence: Named evidence can still be collected.
- Unavailable: Required evidence cannot be collected in this run.
- Waived with evidence: An authorized, scoped exception applies to an established failure.
- Observation: The review records an optional tradeoff without claiming a defect.
A waiver records its scope, authority, evidence, and review condition. It is not a pass or false positive.
Default severity is registry metadata. Use the occurrence’s JSON severity after repository configuration when ordering real findings.
Fix prompt
Apply this candidate correction only after the required evidence confirms the risk.
When the recipient is truly memoized or uses the prop as an identity-sensitive dependency, hoist the immutable empty fallback to module scope and pass that stable constant. Otherwise keep the local fallback: React.lazy by itself does not create a memoization boundary, so changing code only because a lazy wrapper matched the registry has no established benefit.
Repository-wide copy prompt
Use this repository-wide prompt only after validating each occurrence. For one occurrence, use the guidance above.
Show repository-wide prompt
Fix every confirmed react-doctor/prefer-stable-empty-fallback diagnostic in the current repository.
Required change:
- When the recipient is truly memoized or uses the prop as an identity-sensitive dependency, hoist the immutable empty fallback to module scope and pass that stable constant. Otherwise keep the local fallback: React.lazy by itself does not create a memoization boundary, so changing code only because a lazy wrapper matched the registry has no established benefit.
Validation before editing:
Fires on an empty array or object fallback passed to a same-file component that the detector's HOC registry classifies as memoized. Confirm the recipient actually performs prop memoization or otherwise relies on reference identity. React.lazy only defers loading and does not shallow-compare props, so a component wrapped only in lazy or React.lazy is a false positive unless the loaded component is independently memoized. Also suppress other registry wrappers whose installed implementation does not memoize props.
Constraints:
- Make the smallest change that fixes the root cause.
- Preserve behavior and interfaces unrelated to this diagnostic.
- Reuse existing project components, utilities, and conventions.
- Do not introduce render-phase side effects, render-phase state updates, or Hooks rule violations.
- Preserve resource ownership and cleanup. Do not move work into a hotter render or frame path.
- If syntax proves only a candidate cost, require a relevant trace, bundle report, payload measurement, or metric before editing.
- Without evidence, record Needs evidence. Compare the same scenario before and after; keep the change only when its target metric improves without regression.
- Adapt identifiers and framework details instead of copying blindly.
- Do not disable the rule or suppress matching code.
- Do not edit code when this condition applies: react-compiler.
Assessment:
- Record detector evidence, applicability facts, assumptions, missing evidence, and the rule class for this occurrence.
- Return one outcome: Confirmed failure, Rejected, Needs evidence, Unavailable, Waived with evidence, or Observation.
- A waiver records the established failure, scope, authority, evidence, and review or expiry condition. It is not a pass or false positive.
Verification:
- Run focused tests for the changed behavior.
- Run React Doctor and confirm this diagnostic no longer appears from changed code.
- Run an unfiltered scan of the affected scope before claiming no cross-category regression.
- Report the files changed and any checks you could not run.