storybook/lib/cli/generators/SFC_VUE/index.js

const mergeDirs = require('merge-dirs').default;
const helpers = require('../../lib/helpers');
const path = require('path');
const latestVersion = require('latest-version');

module.exports = Promise.all([
  latestVersion('@storybook/vue'),
  latestVersion('@storybook/addon-actions'),
  latestVersion('@storybook/addon-links'),
  latestVersion('babel-preset-vue'),
]).then(([storybookVersion, actionsVersion, linksVersion, babelPresetVersion]) => {
  mergeDirs(path.resolve(__dirname, 'template'), '.', 'overwrite');

  const packageJson = helpers.getPackageJson();

  packageJson.devDependencies = packageJson.devDependencies || {};
  packageJson.devDependencies['@storybook/vue'] = `^${storybookVersion}`;
  packageJson.devDependencies['@storybook/addon-actions'] = `^${actionsVersion}`;
  packageJson.devDependencies['@storybook/addon-links'] = `^${linksVersion}`;
  packageJson.devDependencies['babel-preset-vue'] = `^${babelPresetVersion}`;

  packageJson.scripts = packageJson.scripts || {};
  packageJson.scripts.storybook = 'start-storybook -p 6006';
  packageJson.scripts['build-storybook'] = 'build-storybook';

  helpers.writePackageJson(packageJson);

  const babelRc = helpers.getBabelRc() || {
    presets: [['env', { modules: false }]],
  };
  const hasPreset = babelRc.presets.find(
    preset =>
      (Array.isArray(preset) && preset[0] === 'vue') ||
      (typeof preset === 'string' && preset === 'vue')
  );
  if (!hasPreset) {
    babelRc.presets.push('vue');
  }

  helpers.writeBabelRc(babelRc);
});