Function waitForDrain

out/cli.cjs:55231–55238

()

      let callback = null;
      function onDrain() {
        if (callback) {
          const cb = callback;
          callback = null;
          cb();
        }
      }
      const waitForDrain = () => new Promise((resolve, reject) => {
        assert2(callback === null);
        if (socket[kError]) {
          reject(socket[kError]);
        } else {