# `react-doctor/ink-prefer-use-animation`

Animation loop implemented with setInterval

- **Category:** Performance
- **Severity:** warn
- **Source:** oxlint-plugin-react-doctor
- **Framework:** global
- **Enabled when:** Ink >= 7.0.0

## Validate the diagnostic

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

Confirm the reported code matches `react-doctor/ink-prefer-use-animation`. 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

```tsx
import { Text } from "ink";
import { useEffect, useState } from "react";

const App = () => {
  const [frame, setFrame] = useState(0);
  useEffect(() => {
    const timer = setInterval(() => {
      setFrame((value) => value + 1);
    }, 80);
    return () => clearInterval(timer);
  }, []);
  return <Text>{frame}</Text>;
};
```

### Corrected pattern

```tsx
import { Text, useAnimation } from "ink";

const App = () => {
  const { frame } = useAnimation({ interval: 80 });
  return <Text>{frame}</Text>;
};
```

## 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.

````text
Fix every confirmed `react-doctor/ink-prefer-use-animation` diagnostic in the current repository.

Required change:
- Use Ink's shared `useAnimation()` scheduler and automatic unmount cleanup.

Reference transformation:

Before:
```tsx
import { Text } from "ink";
import { useEffect, useState } from "react";

const App = () => {
  const [frame, setFrame] = useState(0);
  useEffect(() => {
    const timer = setInterval(() => {
      setFrame((value) => value + 1);
    }, 80);
    return () => clearInterval(timer);
  }, []);
  return <Text>{frame}</Text>;
};
```

After:
```tsx
import { Text, useAnimation } from "ink";

const App = () => {
  const { frame } = useAnimation({ interval: 80 });
  return <Text>{frame}</Text>;
};
```

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.
- Preserve resource ownership and cleanup. Do not move work into a hotter render or frame path.
- 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: `Ink >= 7.0.0`.

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.
````