`react-doctor/three-require-owned-material-cleanup`

Locally owned Three.js material is not disposed

Category: Performance
Severity: warn
Source: oxlint-plugin-react-doctor
Framework: global
Enabled when: react, three
Tags: three, webgl
Default: Enabled

Validate the diagnostic

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

Confirm the reported code matches react-doctor/three-require-owned-material-cleanup. 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

useEffect(() => {
  mesh.material = new MeshStandardMaterial();
}, [mesh]);

Corrected pattern

useEffect(() => {
  const material = new MeshStandardMaterial();
  mesh.material = material;
  return () => material.dispose();
}, [mesh]);

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/three-require-owned-material-cleanup diagnostic in the current repository. Required change: - Dispose locally constructed materials when their React owner releases them.

Reference transformation:Before:

useEffect(() => {
  mesh.material = new MeshStandardMaterial();
}, [mesh]);

After:

useEffect(() => {
  const material = new MeshStandardMaterial();
  mesh.material = material;
  return () => material.dispose();
}, [mesh]);

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: react, three. 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 Performance rules from the rules reference:

react-doctor/three-require-owned-texture-cleanup: Locally owned Three.js texture is not disposed
react-doctor/three-shader-no-inverse-of-uniform: Shader inverts a uniform matrix per invocation
react-doctor/three-shader-no-redundant-frag-depth: Shader redundantly writes fragment depth
react-doctor/three-shader-prefer-small-integer-pow: Shader uses pow for a small integer exponent
react-doctor/three-shader-prefer-squared-distance-comparison: Shader compares a computed distance

react-doctor/three-require-owned-material-cleanup