`react-doctor/motion-value-subscription-in-render`

Motion value subscription is created during render

Category: Bugs
Severity: error
Source: oxlint-plugin-react-doctor
Framework: global
Enabled when: always
Default: Enabled

Validate the diagnostic

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

Confirm the reported code matches react-doctor/motion-value-subscription-in-render. 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 { useMotionValue } from "motion/react";

const Slider = () => {
  const motionValue = useMotionValue(0);
  motionValue.on("change", updateLabel);
  return <output>{motionValue.get()}</output>;
};

Corrected pattern

import {
  useMotionValue,
  useMotionValueEvent,
} from "motion/react";

const Slider = () => {
  const motionValue = useMotionValue(0);
  useMotionValueEvent(motionValue, "change", updateLabel);
  return <output>{motionValue.get()}</output>;
};

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/motion-value-subscription-in-render diagnostic in the current repository. Required change: - Subscribe with useMotionValueEvent, or create the subscription in an effect and return its cleanup function.

Reference transformation:Before:

import { useMotionValue } from "motion/react";

const Slider = () => {
  const motionValue = useMotionValue(0);
  motionValue.on("change", updateLabel);
  return <output>{motionValue.get()}</output>;
};

After:

import {
  useMotionValue,
  useMotionValueEvent,
} from "motion/react";

const Slider = () => {
  const motionValue = useMotionValue(0);
  useMotionValueEvent(motionValue, "change", updateLabel);
  return <output>{motionValue.get()}</output>;
};

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. 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/nextjs-async-client-component: Fetch data in a parent Server Component and pass it as props, or use useQuery/useSWR in the client component
react-doctor/nextjs-async-dynamic-api-not-awaited: Synchronous Next.js request API access
react-doctor/nextjs-error-boundary-missing-use-client: Add `'use client'` as the first statement of error.tsx / global-error.tsx so the error boundary becomes a Client Component.
react-doctor/nextjs-global-error-missing-html-body: Wrap the global-error UI in `<html><body>...</body></html>` because the root layout unmounts when global-error renders
react-doctor/nextjs-image-missing-sizes: Add sizes for responsive behavior: `sizes="(max-width: 768px) 100vw, 50vw"` matching your layout breakpoints

react-doctor/motion-value-subscription-in-render