From 09a70e6a835c8726d301796f9a072681db534d5e Mon Sep 17 00:00:00 2001
From: Kei Okada <k-okada@jsk.t.u-tokyo.ac.jp>
Date: Sun, 29 Oct 2023 17:04:11 +0900
Subject: [PATCH] return nil if :get-result called without sending a goal

c.f. https://github.com/yuki-asano/jsk_robot/pull/1#discussion_r1212576855
---
 roseus/euslisp/actionlib.l      | 7 ++++++-
 roseus/test/test-actionlib.test | 2 ++
 2 files changed, 8 insertions(+), 1 deletion(-)

diff --git a/roseus/euslisp/actionlib.l b/roseus/euslisp/actionlib.l
index b44be29e6..6f250ce78 100644
--- a/roseus/euslisp/actionlib.l
+++ b/roseus/euslisp/actionlib.l
@@ -221,7 +221,12 @@
      (if (eq (send self :get-state) actionlib_msgs::GoalStatus::*preempted*)
          (ros::ros-warn "[~A] :wait-for-result finished with preempted status" name-space))
      (eq (send self :get-state) actionlib_msgs::GoalStatus::*succeeded*)))
-  (:get-result () (send (send comm-state :latest-result) :result))
+  (:get-result ()
+   (if (send comm-state :latest-result)
+       (send (send comm-state :latest-result) :result)
+       (progn
+         (ros::ros-error "[~A] :get-result called without sending goal, returns null result" name-space)
+         nil))) ;; return nil instead of (instance action-result-class :init)
   (:get-state ()
     (let (state)
       (setq state (send (send comm-state :latest-goal-status) :status))
diff --git a/roseus/test/test-actionlib.test b/roseus/test/test-actionlib.test
index 4b8d610b0..7dd334fff 100644
--- a/roseus/test/test-actionlib.test
+++ b/roseus/test/test-actionlib.test
@@ -3,5 +3,7 @@
   <node name="fibonacci_client" pkg="roseus" type="roseus" args="$(find roseus)/test/fibonacci-client.l" />
   <test test-name="test_actionlib_client" pkg="roseus" type="roseus" args="$(find roseus)/test/test-actionlib.l"
         time-limit="600" retry="3"/>
+  <test test-name="test_actionlib_client_result_before_start" pkg="roseus" type="roseus" args="$(find roseus)/test/test-actionlib-get-result-before-start.l"
+        time-limit="60" retry="1"/>
 </launch>