[JTC] Cancel goal in on_deactivate (#962)

(cherry picked from commit fdd6142)

joint_trajectory_controller/src/joint_trajectory_controller.cpp

@@ -996,6 +996,17 @@ controller_interface::CallbackReturn JointTrajectoryController::on_activate(
 controller_interface::CallbackReturn JointTrajectoryController::on_deactivate(
   const rclcpp_lifecycle::State &)
 {
+  const auto active_goal = *rt_active_goal_.readFromNonRT();
+  if (active_goal)
+  {
+    rt_has_pending_goal_.writeFromNonRT(false);
+    auto action_res = std::make_shared<FollowJTrajAction::Result>();
+    action_res->set__error_code(FollowJTrajAction::Result::INVALID_GOAL);
+    action_res->set__error_string("Current goal cancelled during deactivate transition.");
+    active_goal->setCanceled(action_res);
+    rt_active_goal_.writeFromNonRT(RealtimeGoalHandlePtr());
+  }
+
   for (size_t index = 0; index < dof_; ++index)
   {
     if (has_position_command_interface_)
@@ -1466,7 +1477,6 @@ void JointTrajectoryController::preempt_active_goal()
   const auto active_goal = *rt_active_goal_.readFromNonRT();
   if (active_goal)
   {
-    add_new_trajectory_msg(set_hold_position());
     auto action_res = std::make_shared<FollowJTrajAction::Result>();
     action_res->set__error_code(FollowJTrajAction::Result::INVALID_GOAL);
     action_res->set__error_string("Current goal cancelled due to new incoming action.");