storybook/examples/official-storybook/config.js

import React from 'react';
import ThemeProvider from '@emotion/provider';
import { configure, addDecorator } from '@storybook/react';
import { themes } from '@storybook/components';
import { withOptions } from '@storybook/addon-options';
import { configureViewport, INITIAL_VIEWPORTS } from '@storybook/addon-viewport';
import { withResources } from '@storybook/addon-resources';

import 'react-chromatic/storybook-addon';
import addHeadWarning from './head-warning';
import extraViewports from './extra-viewports.json';

addHeadWarning('Preview head not loaded', 'preview-head-not-loaded');
addHeadWarning('Dotenv file not loaded', 'dotenv-file-not-loaded');

addDecorator(
  withOptions({
    hierarchySeparator: /\/|\./,
    hierarchyRootSeparator: /\|/,
    theme: themes.dark,
  })
);

addDecorator(
  withResources({
    resources: `<script type="text/javascript" src="https://cdnjs.cloudflare.com/ajax/libs/jquery/3.3.1/jquery.min.js"></script>
<link rel="stylesheet" type="text/css" href="https://stackpath.bootstrapcdn.com/bootstrap/4.1.3/css/bootstrap.min.css"></link>
<link rel="stylesheet" type="text/css" href="https://stackpath.bootstrapcdn.com/font-awesome/4.7.0/css/font-awesome.min.css"></link>
<script type="text/javascript">
  try {
    jQuery( "button" ).click(function() {
      alert( "Handler for .click() called." );
    });
  } catch(e){ }
</script>`,
  })
);

addDecorator(
  (story, { kind }) =>
    kind === 'Core|Errors' ? (
      story()
    ) : (
      <ThemeProvider theme={themes.normal}>{story()}</ThemeProvider>
    )
);

configureViewport({
  viewports: {
    ...INITIAL_VIEWPORTS,
    ...extraViewports,
  },
});

function importAll(req) {
  req.keys().forEach(filename => req(filename));
}

function loadStories() {
  let req;
  req = require.context('../../lib/ui/src', true, /\.stories\.js$/);
  importAll(req);

  req = require.context('../../lib/components/src', true, /\.stories\.js$/);
  importAll(req);

  req = require.context('./stories', true, /\.stories\.js$/);
  importAll(req);
}

configure(loadStories, module);