postcss.config.js

var glob = require('glob');

/**
 * Due to https://github.com/egoist/rollup-plugin-postcss/compare/v2.4.0...v2.4.1
 * switching from push to unshift it's not possible to upgrade past 2.4.0 as long
 * as postcss-import is used.
 */
module.exports = context => {
  return {
    plugins: [
      require('postcss-import'),
      require('postcss-mixins')({
        mixins: require('./src/postcss/mixins'),
      }),
      require('postcss-simple-vars')({
        variables: () => require('./src/postcss/vars'),
      }),
      require('postcss-custom-media')({
        importFrom: [{ customMedia: require('./src/postcss/vars/mediaRules.json') }],
      }),
      require('postcss-nested'),
      require('postcss-extend-rule'),
      require('autoprefixer'),
      require('cssnano')({
        preset: [
          'default',
          {
            mergeLonghand: false,
            discardEmpty: true,
            normalizeWhitespace: true,
          },
        ],
      }),
      context.options.prettify && require('postcss-prettify'),
    ].filter(Boolean),
  };
};