in packages/create-react-app/createReactApp.js [880:899]
function setCaretRangeForRuntimeDeps(packageName) {
const packagePath = path.join(process.cwd(), 'package.json');
const packageJson = require(packagePath);
if (typeof packageJson.dependencies === 'undefined') {
console.error(chalk.red('Missing dependencies in package.json'));
process.exit(1);
}
const packageVersion = packageJson.dependencies[packageName];
if (typeof packageVersion === 'undefined') {
console.error(chalk.red(`Unable to find ${packageName} in package.json`));
process.exit(1);
}
makeCaretRange(packageJson.dependencies, 'react');
makeCaretRange(packageJson.dependencies, 'react-dom');
fs.writeFileSync(packagePath, JSON.stringify(packageJson, null, 2) + os.EOL);
}