Adds support for URL connection strings, with a test to ensure Sequelize gets instantiated correctly

lib/sequelize.js

-var Utils             = require("./utils")
+var url               = require("url")
+  , Utils             = require("./utils")
   , DAOFactory        = require("./dao-factory")
   , DataTypes         = require('./data-types')
   , DAOFactoryManager = require("./dao-factory-manager")
@@ -46,7 +47,31 @@ module.exports = (function() {
     @class Sequelize
     @constructor
   */
-  var Sequelize = function(database, username, password, options) {
+  var Sequelize = function() {
+    var database, username, password, options = {}, urlParts
+
+    if (arguments.length === 1) {
+      urlParts = url.parse(arguments[0])
+      database = urlParts.path.replace(/^\//,  '')
+      dialect = urlParts.protocol
+      options.dialect = urlParts.protocol.replace(/:$/, '')
+      options.host = urlParts.hostname
+
+      if (urlParts.port) {
+        options.port = urlParts.port
+      }
+
+      if (urlParts.auth) {
+        username = urlParts.auth.split(':')[0]
+        password = urlParts.auth.split(':')[1]
+      }
+    } else {
+      database = arguments[0]
+      username = arguments[1]
+      password = arguments[2]
+      options = arguments[3]
+    }
+
     this.options = Utils._.extend({
       dialect: 'mysql',
       host: 'localhost',

spec/configuration.spec.js

+if(typeof require === 'function') {
+  const buster             = require("buster")
+      , CustomEventEmitter = require("../lib/emitters/custom-event-emitter")
+      , Helpers            = require('./buster-helpers')
+      , dialect            = Helpers.getTestDialect()
+}
+
+buster.spec.expose()
+buster.testRunner.timeout = 1000
+
+var Sequelize = require(__dirname + '/../index')
+
+describe(Helpers.getTestDialectTeaser("Configuration"), function() {
+  describe('Instantiation with a URL string', function() {
+    it('should accept username, password, host, port, and database', function() {
+      var sequelize = new Sequelize('mysql://user:pass@example.com:9821/dbname')
+      var config = sequelize.config
+      var options = sequelize.options
+
+      expect(options.dialect).toEqual('mysql')
+
+      expect(config.database).toEqual('dbname')
+      expect(config.host).toEqual('example.com')
+      expect(config.username).toEqual('user')
+      expect(config.password).toEqual('pass')
+      expect(config.port).toEqual(9821)
+    })
+
+    it('should work with no authentication options', function() {
+      var sequelize = new Sequelize('mysql://example.com:9821/dbname')
+      var config = sequelize.config
+
+      expect(config.username).toEqual(undefined)
+      expect(config.password).toEqual(null)
+    })
+
+    it('should use the default port when no other is specified', function() {
+      var sequelize = new Sequelize('mysql://example.com/dbname')
+      var config = sequelize.config
+
+      // The default port should be set
+      expect(config.port).toEqual(3306)
+    })
+  })
+
+  describe('Intantiation with arguments', function() {
+    it('should accept two parameters (database, username)', function() {
+      var sequelize = new Sequelize('dbname', 'root')
+      var config = sequelize.config
+
+      expect(config.database).toEqual('dbname')
+      expect(config.username).toEqual('root')
+    })
+
+    it('should accept three parameters (database, username, password)', function() {
+      var sequelize = new Sequelize('dbname', 'root', 'pass')
+      var config = sequelize.config
+
+      expect(config.database).toEqual('dbname')
+      expect(config.username).toEqual('root')
+      expect(config.password).toEqual('pass')
+    })
+
+    it('should accept four parameters (database, username, password, options)', function() {
+      var sequelize = new Sequelize('dbname', 'root', 'pass', { port: 999 })
+      var config = sequelize.config
+
+      expect(config.database).toEqual('dbname')
+      expect(config.username).toEqual('root')
+      expect(config.password).toEqual('pass')
+      expect(config.port).toEqual(999)
+    })
+  })
+})