Function unmountComponentAtNode

packages/react-dom/src/client/ReactDOMRootFB.js:435–508

(container: Container)

}

export function unmountComponentAtNode(container: Container): boolean {
  if (disableLegacyMode) {
    if (__DEV__) {
      console.error(
        'unmountComponentAtNode was removed in React 19. Use root.unmount() instead.',
      );
    }
    throw new Error('ReactDOM: Unsupported Legacy Mode API.');
  }
  if (!isValidContainer(container)) {
    throw new Error('Target container is not a DOM element.');
  }

  if (__DEV__) {
    const isModernRoot =
      isContainerMarkedAsRoot(container) &&
      container._reactRootContainer === undefined;
    if (isModernRoot) {
      console.error(
        'You are calling ReactDOM.unmountComponentAtNode() on a container that was previously ' +
          'passed to ReactDOMClient.createRoot(). This is not supported. Did you mean to call root.unmount()?',
      );
    }
  }

  if (container._reactRootContainer) {
    const root = container._reactRootContainer;

    if (__DEV__) {
      const rootEl = getReactRootElementInContainer(container);
      const renderedByDifferentReact = rootEl && !getInstanceFromNode(rootEl);
      if (renderedByDifferentReact) {
        console.error(
          "unmountComponentAtNode(): The node you're attempting to unmount " +
            'was rendered by another copy of React.',
        );
      }
    }

    updateContainerSync(null, root, null, null);
    flushSyncWork();
    // $FlowFixMe[incompatible-type] This should probably use `delete container._reactRootContainer`
    container._reactRootContainer = null;
    unmarkContainerAsRoot(container);
    return true;
  } else {
    if (__DEV__) {
      const rootEl = getReactRootElementInContainer(container);
      const hasNonRootReactChild = !!(rootEl && getInstanceFromNode(rootEl));

      // Check if the container itself is a React root node.
      const isContainerReactRoot =
        container.nodeType === ELEMENT_NODE &&
        isValidContainer(container.parentNode) &&
        // $FlowFixMe[prop-missing]
        // $FlowFixMe[incompatible-use]
        !!container.parentNode._reactRootContainer;