message: remove update from attach since it can confuse two fields
diff: @@ -404,15 +404,6 @@ export default class Validator {
  }, arguments[2] || { vm: { $validator: this } });
  }
  - // try to find exisitng field.
  - const exists = this.fields.find({ name: field.name, scope: field.scope || null });
  - if (exists) {
  - // patch it instead.
  - exists.update(field); // update its options.
  - this.errors.remove(field.name, field.scope || null);
  - return exists;
  - }
  -
  if (!(field instanceof Field)) {
  field = new Field(field.el || null, field);
  }
  