From a349c5bfebffed3e00e87038ea4b49ad039e2755 Mon Sep 17 00:00:00 2001
From: tianshujie <tianshujie@easycorp.ltd>
Date: Wed, 9 Mar 2022 14:01:41 +0800
Subject: [PATCH] * Fix bug #20530.

---
 module/execution/js/kanban.js     | 1 +
 module/execution/js/taskkanban.js | 1 +
 module/kanban/js/view.js          | 1 +
 3 files changed, 3 insertions(+)

diff --git a/module/execution/js/kanban.js b/module/execution/js/kanban.js
index d39357a3bc..9350f13cd2 100644
--- a/module/execution/js/kanban.js
+++ b/module/execution/js/kanban.js
@@ -792,6 +792,7 @@ function handleDropTask($element, event, kanban)
     var newLane  = $newCol.closest('.kanban-lane').data('lane');
     var cardType = $card.find('.kanban-card').data('type');
 
+    if(!oldCol || !newCol || !newLane || !oldLane) return false;
     if(oldCol.id === newCol.id && newLane.id === oldLane.id) return false;
 
     var cardID      = $card.data().id;
diff --git a/module/execution/js/taskkanban.js b/module/execution/js/taskkanban.js
index d10800f92b..7f6ef45962 100644
--- a/module/execution/js/taskkanban.js
+++ b/module/execution/js/taskkanban.js
@@ -717,6 +717,7 @@ function handleDropTask($element, event, kanban)
     var newLane  = $newCol.closest('.kanban-lane').data('lane');
     var cardType = $card.find('.kanban-card').data('type');
 
+    if(!oldCol || !newCol || !newLane || !oldLane) return false;
     if(oldCol.id === newCol.id && newLane.id === oldLane.id) return false;
 
     var cardID      = $card.data().id;
diff --git a/module/kanban/js/view.js b/module/kanban/js/view.js
index bf5a191c4e..42c5a8a36a 100644
--- a/module/kanban/js/view.js
+++ b/module/kanban/js/view.js
@@ -976,6 +976,7 @@ function handleDropTask($element, event, kanban)
     var regionID = $card.closest('.region').data('id');
     var kanbanID = $card.closest('#kanban').data('id');
 
+    if(!oldCol || !newCol || !newLane || !oldLane) return false;
     if(oldCol.id === newCol.id && newLane.id === oldLane.id) return false;
 
     var cardID = $card.data().id;