hotrod.js

function cache() {
  get = function(k) {
    return function(client) {
      return client.get(k);
    }
  }
  put = function(k, v) {
    return function(client) {
      return client.put(k, v);
    }
  }
}

var before = client.stats().then(function(beforeStats) { return beforeStats } );
var put = before.then(cache().put('k', 'v'));
var after = put.then(function() { return client.stats(); });
Promise.all([before, after]).then(function(results) {
  // results is an array of 2 elements, with the stats before and stats after
  expect(results[1].stores).toBe(results[0].stores + 1);
});