text: // setup.js
  const path = require('path');
  
  const fs = require('fs');
  
  const {MongoMemoryServer} = require('mongodb-memory-server');
  
  const globalConfigPath = path.join(__dirname, 'globalConfig.json');
  
  const mongod = new MongoMemoryServer({
    autoStart: false,
  });
  
  module.exports = async () => {
    if (!mongod.isRunning) {
      await mongod.start();
    }
  
    const mongoConfig = {
      mongoDBName: 'jest',
      mongoUri: await mongod.getUri(),
    };
  
    // Write global config to disk because all tests run in different contexts.
    fs.writeFileSync(globalConfigPath, JSON.stringify(mongoConfig));
  
    // Set reference to mongod in order to close the server during teardown.
    global.__MONGOD__ = mongod;
  };
  