new.js

Promotion.pre('save', true, function(next, done) {
  next();
  var self = this;
  short.generate(settings.baseURL + '/promotion/' + this._id + '/show', function(err, url) {
    self.url = settings.baseURL + '/' + url.hash;
    done();
  })
})

Promotion.pre('save', true, function(next, done) {
  next()
  Release.update({_id: this._release}, {'$push': {_promotions: this._id}},
      function(err, count) {
        if(err) throw err;
        done();
      }
  );
})

Promotion.pre('save', true, function(next, done) {
  next()
  User.update({_id: this._promoter}, {'$push': {_promotions: this._id}},
      function(err, count) {
        if(err) throw err;
        done();
      }
  );
})

old.js

Promotion.statics.createFor = function createFor(promoter, release, callback) {
  var promotion = new this({
      _promoter: promoter,
      _release: release
  });
  short.generate(settings.baseURL + '/promotion/' + promotion._id + '/show', function(err, url) {
    promotion.url = settings.baseURL + '/' + url.hash  
    promotion.save(function(err) {
      var fields = {'$push': {_promotions: promotion._id}};
      async.series([function(cb) {
        User.update({_id: promoter}, fields, cb)
      }, function(cb) {
        Release.update({_id: release}, fields, cb) 
      }],
      callback(err, promotion))
    });
  })

}

test.js

var app = require('test_helper')

describe('Promotion', function() {
  var user = {}
    , release = {}

  var fixtures = {
    user: function(cb) {
      User.create({displayName: 'Bob Barker'}, cb)
    },
    release: function(cb) {
      Release.create({title: 'Golden Oldies'}, cb)
    }
  }

  before(function(done) {
    async.series(fixtures, function(err, results) {
      if(err) throw err;
      user = results.user;
      release = results.release;
      done();
    })
  })

  //after(function(done) {
    //mongoose.connection.db.executeDbCommand( {dropDatabase:1}, 
       //function(err, result) { 
         //if(err) throw err;
         //done();
    //}) 
  //})

  describe('#save', function() {
    it("updates the user object", function(done) {
      var promotion = new Promotion({_promoter: user._id, _release: release._id})
      promotion.save(function(err) { throw err; })
      User.findById(user._id, function(err, u) {
        if(err) throw err;
        _.last(u._promotions).should.eql(promotion._id)
        done();
      })
    })

    it("updates the release object", function(done) {
      var promotion = new Promotion({_promoter: user._id, _release: release._id})
      promotion.save(function(err) { throw err; })
      Release.findById(release._id, function(err, r) {
        if(err) throw err;
        _.last(r._promotions).should.eql(promotion._id)
        done();
      })
    })

    it("creates a short url", function(done) {
      var promotion = new Promotion({_promoter: user._id, _release: release._id})
      var longURL = 'http://localhost:3001/promotion/'+promotion._id+'/show'
      promotion.save(function(err) { 
        inspect(err)
        throw err; 
      });
      Promotion.findOne(promotion, function(err, p) {
        if(err) throw err;
        short.retrieve(_.strRightBack(p.url, '/'), function(err, url) {
          done()
        }) 
      })
    })
  })
})