keep original error message when wrapping in DatabaseError

fixes #2521

lib/errors.js

@@ -72,7 +72,7 @@ error.ValidationError.prototype.errors;
  * @constructor
  * @constructor
  */
  */
 error.DatabaseError = function (parent) {
 error.DatabaseError = function (parent) {
-  error.BaseError.apply(this, arguments);
+  error.BaseError.apply(this, [parent.message]);
   this.name = 'SequelizeDatabaseError';
   this.name = 'SequelizeDatabaseError';
 
 
   this.parent = parent;
   this.parent = parent;

test/error.test.js

@@ -55,6 +55,14 @@ describe(Support.getTestDialectTeaser("Sequelize Errors"), function () {
       expect(matches).to.have.lengthOf(1);
       expect(matches).to.have.lengthOf(1);
       expect(matches[0]).to.have.property('message', 'invalid');
       expect(matches[0]).to.have.property('message', 'invalid');
     });
     });
+    it('SequelizeDatabaseError should keep original message', function() {
+      var orig = new Error('original database error message');
+      var databaseError = new Sequelize.DatabaseError(orig);
+
+      expect(databaseError).to.have.property('parent');
+      expect(databaseError.name).to.equal('SequelizeDatabaseError');
+      expect(databaseError.message).to.equal('original database error message');
+    });
   });
   });
 
 
   describe('Constraint error', function () {
   describe('Constraint error', function () {