react-native-google-mobile-ads/src/common/ref.ts

React Native Google Mobile Ads is an easy way to monetize mobile apps with targeted, in-app advertising.

import React from 'react';

type PossibleRef<T> = React.Ref<T> | undefined;
interface ElementWithRef extends React.ReactElement {
  ref?: PossibleRef<unknown>;
}

/**
 * Access the ref using the method that doesn't yield a warning.
 *
 * Before React 19 accessing `element.props.ref` will throw a warning and suggest using `element.ref`
 * After React 19 accessing `element.ref` does the opposite.
 * https://github.com/facebook/react/pull/28348
 */
export function getElementRef(element: React.ReactElement): PossibleRef<unknown> {
  // React <=18 in DEV
  let getter = Object.getOwnPropertyDescriptor(element.props, 'ref')?.get;
  let mayWarn = getter && 'isReactWarning' in getter && getter.isReactWarning;
  if (mayWarn) {
    return (element as ElementWithRef).ref;
  }

  // React 19 in DEV
  getter = Object.getOwnPropertyDescriptor(element, 'ref')?.get;
  mayWarn = getter && 'isReactWarning' in getter && getter.isReactWarning;
  if (mayWarn) {
    return element.props.ref;
  }

  // Not DEV
  return element.props.ref || (element as ElementWithRef).ref;
}

export function composeRefs<T>(...refs: PossibleRef<T>[]) {
  return (value: T) => {
    refs.forEach(ref => {
      if (typeof ref === 'function') {
        ref(value);
      } else if (ref !== null && ref !== undefined) {
        (ref as React.MutableRefObject<T>).current = value;
      }
    });
  };
}