Function delKeys

test/delay-test.js:11–23

(client, pattern)

const {EventEmitter: Emitter} = require('events');

function delKeys(client, pattern) {
  const promise = helpers.deferred(),
    done = promise.defer();
  client.keys(pattern, (err, keys) => {
    if (err) return done(err);
    if (keys.length) {
      client.del(keys, done);
    } else {
      done();
    }
  });
  return promise;
}

// A promise-based barrier.
function reef(n = 1) {