react-doctor/no-redundant-should-component-update
Review shouldComponentUpdate overrides on PureComponent; deleting an override changes behavior unless it is proven equivalent to the inherited shallow comparison
- Status
- Active
- Category
- Architecture
- Assessment
- Evidence-required risk
- Required evidence
- source code, repository context
- Default configuration
- Enabled
- Default severity
- warn
Show technical metadata
- Scope
- All supported frameworks
- Active when
- always
- Requirements
- react
- Priority
- 34 (P3)
- Source
- oxlint-plugin-react-doctor
- Rule set
- oxlint-plugin-react-doctor 0.9.3 (prompt schema 2)
- Documentation
- Official documentation
Validation prompt
Confirm the detector match and collect the required evidence before deciding whether an edit is warranted.
Fires when a class extends PureComponent (a bare identifier named PureComponent or the React.PureComponent member expression) and defines shouldComponentUpdate. The override replaces PureComponent's inherited implementation; it is not automatically redundant. Inspect the method body and callers to determine whether it intentionally performs a different comparison. Also confirm the superclass resolves to React PureComponent because matching is name-based.
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.
Preserve an intentional custom comparison and switch the base class to React.Component so the update policy is explicit. Delete shouldComponentUpdate only after proving it is equivalent to PureComponent's shallow prop and state comparison and focused tests cover skipped and accepted updates. Do not mechanically delete the override: doing so can change which renders occur. See https://react.dev/reference/react/PureComponent
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/no-redundant-should-component-update diagnostic in the current repository.
Required change:
- Preserve an intentional custom comparison and switch the base class to React.Component so the update policy is explicit. Delete shouldComponentUpdate only after proving it is equivalent to PureComponent's shallow prop and state comparison and focused tests cover skipped and accepted updates. Do not mechanically delete the override: doing so can change which renders occur. See https://react.dev/reference/react/PureComponent.
Validation before editing:
Fires when a class extends PureComponent (a bare identifier named PureComponent or the React.PureComponent member expression) and defines shouldComponentUpdate. The override replaces PureComponent's inherited implementation; it is not automatically redundant. Inspect the method body and callers to determine whether it intentionally performs a different comparison. Also confirm the superclass resolves to React PureComponent because matching is name-based.
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.
- Adapt identifiers and framework details instead of copying blindly.
- Do not disable the rule or suppress matching code.
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.