Function normalizePackageJson

packages/next/src/utils.ts:155–201

* Enforce specific package.json configuration for smallest possible lambda

(
  defaultPackageJson: {
    dependencies?: stringMap;
    devDependencies?: stringMap;
    scripts?: stringMap;
  } = {}
)

 * Enforce specific package.json configuration for smallest possible lambda
 */
function normalizePackageJson(
  defaultPackageJson: {
    dependencies?: stringMap;
    devDependencies?: stringMap;
    scripts?: stringMap;
  } = {}
) {
  const dependencies: stringMap = {};
  const devDependencies: stringMap = {
    ...defaultPackageJson.dependencies,
    ...defaultPackageJson.devDependencies,
  };

  if (devDependencies.react) {
    dependencies.react = devDependencies.react;
    delete devDependencies.react;
  }

  if (devDependencies['react-dom']) {
    dependencies['react-dom'] = devDependencies['react-dom'];
    delete devDependencies['react-dom'];
  }

  delete devDependencies['next-server'];

  return {
    ...defaultPackageJson,
    dependencies: {
      // react and react-dom can be overwritten
      react: 'latest',
      'react-dom': 'latest',
      ...dependencies, // override react if user provided it
      // next-server is forced to canary
      'next-server': 'v7.0.2-canary.49',
    },
    devDependencies: {
      ...devDependencies,
      // next is forced to canary
      next: 'v7.0.2-canary.49',
    },
    scripts: {
      ...defaultPackageJson.scripts,
      'now-build':
        'NODE_OPTIONS=--max_old_space_size=3000 next build --lambdas',
    },
  };
}

async function getNextConfig(workPath: string, entryPath: string) {
  const entryConfig = path.join(entryPath, './next.config.js');