change-webpack-to-metro.ts

import {
  Tree,
  formatFiles,
  getProjects,
  updateProjectConfiguration,
  updateJson,
} from '@nx/devkit';

/**
 * Migration:
 * - change target 'export-web'
 * - change bundler to 'metro'
 */
export default async function update(tree: Tree) {
  const projects = getProjects(tree);

  for (const [name, config] of projects.entries()) {
    if (config.targets?.['start']?.executor === '@nx/expo:start') {
      if (config.targets['web']) {
        delete config.targets['web'];
      }
      if (config.targets['export-web']) {
        config.targets['export-web'].options.bundler = 'metro';
      }

      updateJson(tree, `${config.root}/app.json`, (appJson) => {
        if (appJson.expo?.web) {
          appJson.expo.web.bundler = 'metro';
        }
        return appJson;
      });
    }

    updateProjectConfiguration(tree, name, config);
  }

  await formatFiles(tree);
}