How to use the wd.addAsyncMethod function in wd

'    <span>one</span>\n' +
    '    <span>two</span>\n' +
    '    <span>three</span>\n' +
    '  \n' +
    '\n';
  it('wd.addElementPromisedMethod (no-chain)', function() {
    _(extraElementPromiseNoChainMethods).each(function(method, name) {
      wd.addElementPromiseMethod(name, method);
    });
    return browser
      .elementById('div1')
      .textTwice()
      .should.become('one twoone two');
  });

  partials['wd.addAsyncMethod'] =
    '<div id="theDiv">Hello World!</div>';
  it('wd.addAsyncMethod', function() {
    _(extraAsyncMethods).each(function(method, name) {
      wd.addAsyncMethod(name, method);
    });
    return browser
      // .sleepAndElementById('theDiv')
      //   .should.be.fulfilled
      // .sleepAndText()
      //   .should.be.fulfilled
      // .sleepAndElementById('theDiv')
      // .sleepAndText().should.eventually.include("Hello World!")
      .elementByCssWhenReady('#theDiv', 500).text()
        .should.become("Hello World!");
  });

should.not.exist(wd.Webdriver.prototype[name]);
    });
  };

  beforeEach(function() {
    noExtraMethodCheck();
  });

  afterEach(function() {
    _(allExtraMethodNames).each(function(name) {
      wd.removeMethod(name);
    });
    noExtraMethodCheck();
  });

  partials['wd.addAsyncMethod'] =
    '<div id="theDiv">Hello World!</div>';
  it('wd.addAsyncMethod', function(done) {
    _(extraAsyncMethods).each(function(method, name) {
      wd.addAsyncMethod(name, method);
    });
    browser.sleepAndElementById('theDiv', function(err, el) {
      if(err) { return done(err); }
      el.should.exist;
      browser.sleepAndText(el, function(err,text) {
        if(err) { return done(err); }
        text.should.equal('Hello World!');
        done();
      });
    });
  });

'    <span>three</span>\n' +
    '  \n' +
    '\n';
  it('wd.addElementPromisedMethod', function() {
    _(extraElementPromiseNoChainMethods).each(function(method, name) {
      wd.addElementPromiseMethod(name, method);
    });
    return browser
      .elementById('div1')
      .then(function(el) { return el.textTwice(); })
      .then(function(result ) {
        result.should.equal('one twoone two');
      });
  });

  partials['wd.addAsyncMethod'] =
    '<div id="theDiv">Hello World!</div>';
  it('wd.addAsyncMethod', function() {
    _(extraAsyncMethods).each(function(method, name) {
      wd.addAsyncMethod(name, method);
    });
    return browser
      .sleepAndElementById('theDiv').should.be.fulfilled
      .then(function() {
        return browser.sleepAndText().should.be.fulfilled;
      }).then(function() {
        return browser.sleepAndElementById('theDiv');
      }).then(function(el){
        return browser.sleepAndText(el).should.become("Hello World!");
      });
  });