mocha-describe-folder.js

const path = require('path');
const fs = require('fs');

delete require.cache[__filename];

module.exports = (name, extra = () => {}) => describe(name, function() {
  extra.call(this);
  
  const parent = module.parent.filename;
  const parentDir = path.dirname(parent);
  const files = fs.readdirSync(parentDir)
    .map(file => path.join(parentDir, file))
    .filter(file => file !== parent);

  files.forEach(require);
});