react/no-render-return-value

ReactDOM.render returns the root component's instance, but only if React has rendered it by the time the call returns. React doesn't promise that. To get the instance, give the root element a ref callback. React calls it when the instance exists.

The rule reports the call when its result is stored in a variable or a property, assigned, or returned.

Configure

Off by default. To turn it on:

[lint.rules]
"react/no-render-return-value" = "error" # or "warn"

Examples

Reported:

const app = ReactDOM.render(<App />, document.body);

function mount(root) {
  return ReactDOM.render(<App />, root);
}

Not reported:

let app;

ReactDOM.render(<App ref={instance => (app = instance)} />, document.body);