Assembly: Use canDragObjectToTarget in viewProviderAssembly

src/Gui/Tree.cpp

@@ -2118,6 +2118,10 @@ bool TreeWidget::dropInDocument(QDropEvent* event, TargetItemInfo& targetInfo,
     infos.reserve(items.size());
     bool syncPlacement = TreeParams::getSyncPlacement();
 
+    App::AutoTransaction committer(
+        da == Qt::LinkAction ? "Link object" :
+        da == Qt::CopyAction ? "Copy object" : "Move object");
+
     // check if items can be dragged
     for (auto& v : items) {
         auto item = v.first;
@@ -2127,15 +2131,17 @@ bool TreeWidget::dropInDocument(QDropEvent* event, TargetItemInfo& targetInfo,
             auto vpp = parentItem->object();
             // We querry all the parents recursively.
             bool allParentsOK = true;
-            while (parentItem) {
-                if (!parentItem->object()->canDragObjectToTarget(obj, nullptr)) {
+            auto parentItemRecursive = parentItem;
+            while (parentItemRecursive) {
+                if (!parentItemRecursive->object()->canDragObjectToTarget(obj, nullptr)) {
                     allParentsOK = false;
                     break;
                 }
-                parentItem = parentItem->getParentItem();
+                parentItemRecursive = parentItemRecursive->getParentItem();
             }
 
             if (!allParentsOK || !parentItem->object()->canDragObjects() || !parentItem->object()->canDragObject(obj)) {
+                committer.close(true);
                 TREE_ERR("'" << obj->getFullName() << "' cannot be dragged out of '" << parentItem->object()->getObject()->getFullName() << "'");
                 return false;
             }
@@ -2174,9 +2180,6 @@ bool TreeWidget::dropInDocument(QDropEvent* event, TargetItemInfo& targetInfo,
 
     // Open command
     auto manager = Application::Instance->macroManager();
-    App::AutoTransaction committer(
-        da == Qt::LinkAction ? "Link object" :
-        da == Qt::CopyAction ? "Copy object" : "Move object");
     try {
         std::vector<App::DocumentObject*> droppedObjs;
         for (auto& info : infos) {

src/Mod/Assembly/Gui/ViewProviderAssembly.cpp

@@ -138,16 +138,27 @@ bool ViewProviderAssembly::canDragObject(App::DocumentObject* obj) const
         return false;
     }
 
-    // else if a solid is removed, remove associated joints if any.
+    return true;
+}
+
+bool ViewProviderAssembly::canDragObjectToTarget(App::DocumentObject* obj,
+                                                 App::DocumentObject* target) const
+{
+    // If a solid is removed from the assembly, its joints need to be removed.
     bool prompted = false;
     auto* assemblyPart = static_cast<AssemblyObject*>(getObject());
 
+    // If target is null then it's being dropped on a doc.
+    if (target && assemblyPart->hasObject(target)) {
+        // If the obj stays in assembly then its ok.
+        return true;
+    }
+
     // Combine the joints and groundedJoints vectors into one for simplicity.
     std::vector<App::DocumentObject*> allJoints = assemblyPart->getJoints();
     std::vector<App::DocumentObject*> groundedJoints = assemblyPart->getGroundedJoints();
     allJoints.insert(allJoints.end(), groundedJoints.begin(), groundedJoints.end());
 
-    Gui::Command::openCommand(tr("Delete associated joints").toStdString().c_str());
     for (auto joint : allJoints) {
         // getLinkObjFromProp returns nullptr if the property doesn't exist.
         App::DocumentObject* obj1 = AssemblyObject::getObjFromProp(joint, "Object1");
@@ -175,7 +186,6 @@ bool ViewProviderAssembly::canDragObject(App::DocumentObject* obj) const
                                     joint->getNameInDocument());
         }
     }
-    Gui::Command::commitCommand();
 
     return true;
 }

src/Mod/Assembly/Gui/ViewProviderAssembly.h

@@ -88,6 +88,8 @@ public:
     }
 
     bool canDragObject(App::DocumentObject*) const override;
+    bool canDragObjectToTarget(App::DocumentObject* obj,
+                               App::DocumentObject* target) const override;
 
     App::DocumentObject* getActivePart() const;