Added logic for when an error doesn't have an `code` property.

lib/dialects/mysql/connection-manager.js

@@ -41,25 +41,29 @@ ConnectionManager.prototype.connect = function(config) {
 
     connection.connect(function(err) {
       if (err) {
-        switch (err.code) {
-        case 'ECONNREFUSED':
-          reject(new sequelizeErrors.ConnectionRefusedError(err));
-          break;
-        case 'ER_ACCESS_D2ENIED_ERROR':
-          reject(new sequelizeErrors.AccessDeniedError(err));
-          break;
-        case 'ENOTFOUND':
-          reject(new sequelizeErrors.HostNotFoundError(err));
-          break;
-        case 'EHOSTUNREACH':
-          reject(new sequelizeErrors.HostNotReachableError(err));
-          break;
-        case 'EINVAL':
-          reject(new sequelizeErrors.InvalidConnectionError(err));
-          break;
-        default:
+        if (err.code) {
+          switch (err.code) {
+          case 'ECONNREFUSED':
+            reject(new sequelizeErrors.ConnectionRefusedError(err));
+            break;
+          case 'ER_ACCESS_D2ENIED_ERROR':
+            reject(new sequelizeErrors.AccessDeniedError(err));
+            break;
+          case 'ENOTFOUND':
+            reject(new sequelizeErrors.HostNotFoundError(err));
+            break;
+          case 'EHOSTUNREACH':
+            reject(new sequelizeErrors.HostNotReachableError(err));
+            break;
+          case 'EINVAL':
+            reject(new sequelizeErrors.InvalidConnectionError(err));
+            break;
+          default:
+            reject(new sequelizeErrors.ConnectionError(err));
+            break;
+          }
+        } else {
           reject(new sequelizeErrors.ConnectionError(err));
-          break;
         }
 
         return;