Get Node VM results from an async script

index.js

const vm = require('vm');

(async () => {
  const sandbox = {
    a: 1
  };
  await new Promise(resolve => {
    sandbox.resolve = resolve;
    const code = 'Promise.resolve(2).then(result => {a = result; resolve();})';
    const script = new vm.Script(code);
    const context = new vm.createContext(sandbox);
    script.runInContext(context);
  });
  console.log(sandbox.a); // 2
})();