func (m *MockConn) Do(cmd string, cmdArgs ...interface{}) (interface{}, error) { m.Mutex.Lock() defer m.Mutex.Unlock() var args mock.Arguments if len(cmdArgs) == 0 { args = m.Mock.Called(cmd) } else { args = m.Mock.Called(cmd, cmdArgs) } return args.Get(0), args.Error(1) }