`react-doctor/mobx-no-make-auto-observable-in-inheritance`

Unsupported MobX auto-observable inheritance

Category: Bugs
Severity: error
Source: oxlint-plugin-react-doctor
Framework: global
Enabled when: mobx:6
Default: Enabled

Validate the diagnostic

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

Confirm the reported code matches react-doctor/mobx-no-make-auto-observable-in-inheritance. 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 { makeAutoObservable } from "mobx";

class TodoStore extends BaseStore {
  todos = [];

  addTodo(todo) {
    this.todos.push(todo);
  }

  constructor() {
    super();
    makeAutoObservable(this);
  }
}

Corrected pattern

import { action, makeObservable, observable } from "mobx";

class TodoStore extends BaseStore {
  todos = [];

  addTodo(todo) {
    this.todos.push(todo);
  }

  constructor() {
    super();
    makeObservable(this, {
      todos: observable,
      addTodo: action,
    });
  }
}

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/mobx-no-make-auto-observable-in-inheritance diagnostic in the current repository. Required change: - Replace inheritance with composition, or annotate inherited members explicitly with makeObservable.

Reference transformation:Before:

import { makeAutoObservable } from "mobx";

class TodoStore extends BaseStore {
  todos = [];

  addTodo(todo) {
    this.todos.push(todo);
  }

  constructor() {
    super();
    makeAutoObservable(this);
  }
}

After:

import { action, makeObservable, observable } from "mobx";

class TodoStore extends BaseStore {
  todos = [];

  addTodo(todo) {
    this.todos.push(todo);
  }

  constructor() {
    super();
    makeObservable(this, {
      todos: observable,
      addTodo: action,
    });
  }
}

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: mobx:6. 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/mobx-no-observer-wrapped-memo: Invalid MobX observer wrapper order
react-doctor/mobx-reaction-disposer-discarded: MobX reaction disposer discarded
react-doctor/motion-animate-presence-must-outlive-child: AnimatePresence unmounts with its exiting child
react-doctor/motion-animate-presence-requires-key: AnimatePresence child is missing a key
react-doctor/motion-animate-presence-wait-single-child: AnimatePresence wait mode has multiple children

react-doctor/mobx-no-make-auto-observable-in-inheritance