`react-doctor/valtio-no-snapshot-in-callback`

Valtio snapshot read in a callback

Category: Bugs
Severity: warn
Source: oxlint-plugin-react-doctor
Framework: global
Enabled when: react, valtio, valtio:1
Default: Enabled

Validate the diagnostic

Confirm the reported code matches this rule before you edit it.

Confirm the reported code matches react-doctor/valtio-no-snapshot-in-callback. Compare it with the Before example and verify the same API, framework, and execution context. Treat it as a false positive only when one of those conditions differs.

Compare the code

The corrected pattern shows a focused way to address the diagnostic.

Reported pattern

import { useSnapshot } from "valtio";

const Counter = () => {
  const snapshot = useSnapshot(store);
  return (
    <button type="button" onClick={() => save(snapshot.count)}>
      Save
    </button>
  );
};

Corrected pattern

const Counter = () => {
  return (
    <button type="button" onClick={() => save(store.count)}>
      Save
    </button>
  );
};

How to fix

Use the corrected pattern as a reference. Preserve behavior that the rule does not require you to change.

Copyable fix prompt

Copy this self-contained prompt into your coding agent after you confirm the diagnostic.

Fix every confirmed react-doctor/valtio-no-snapshot-in-callback diagnostic in the current repository. Required change: - Read from the original Valtio proxy inside callbacks. useSnapshot() results are for render reads; callback reads can become tracked render dependencies and cause extra re-renders.

Reference transformation:Before:

import { useSnapshot } from "valtio";

const Counter = () => {
  const snapshot = useSnapshot(store);
  return (
    <button type="button" onClick={() => save(snapshot.count)}>
      Save
    </button>
  );
};

After:

const Counter = () => {
  return (
    <button type="button" onClick={() => save(store.count)}>
      Save
    </button>
  );
};

Constraints: - Confirm the reported code matches the Before pattern. - 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. - Confirm this rule is enabled for the project: react, valtio, valtio:1. Verification: - Run focused tests for the changed behavior. - Run React Doctor and confirm this diagnostic no longer appears. - Report the files changed and any checks you could not run.

More Bugs rules from the rules reference:

react-doctor/void-dom-elements-no-children: Remove children from the void element, or use a non-void element if children are needed.
react-doctor/waapi-animation-in-render: Web Animation starts during render
react-doctor/web-animation-offsets-valid: Invalid Web Animation keyframe offsets
react-doctor/zustand-no-get-during-initialization: Zustand get() called during store initialization
react-doctor/zustand-no-mutating-state: Zustand state mutated in place

react-doctor/valtio-no-snapshot-in-callback