From 1ad7724d503c6e85636f5e64127ca6d6c78e094f Mon Sep 17 00:00:00 2001
From: wmayer <wmayer@users.sourceforge.net>
Date: Sun, 31 Dec 2017 01:57:44 +0100
Subject: [PATCH] avoid error 'Duplicate constraint not allowed' when deleting
 a constraint

---
 src/Mod/Sketcher/Gui/TaskSketcherConstrains.cpp | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/src/Mod/Sketcher/Gui/TaskSketcherConstrains.cpp b/src/Mod/Sketcher/Gui/TaskSketcherConstrains.cpp
index 41a5022004..4296a3ee34 100644
--- a/src/Mod/Sketcher/Gui/TaskSketcherConstrains.cpp
+++ b/src/Mod/Sketcher/Gui/TaskSketcherConstrains.cpp
@@ -782,8 +782,15 @@ void TaskSketcherConstrains::slotConstraintsChanged(void)
             break;
         }
 
+        // block signals as there is no need to invoke the
+        // on_listWidgetConstraints_itemChanged() slot in
+        // case a name has changed because this function gets
+        // called after changing the constraint list property
+        QAbstractItemModel* model = ui->listWidgetConstraints->model();
+        bool block = model->blockSignals(true);
         it->setHidden(!visible);
         it->setData(Qt::EditRole, Base::Tools::fromStdString(constraint->Name));
+        model->blockSignals(block);
     }
 }