Ensure objects to be in a single GeoFeatureGroup only

src/App/GeoFeatureGroupExtension.cpp

@@ -178,6 +178,38 @@ std::vector<DocumentObject*> GeoFeatureGroupExtension::removeObjects(std::vector
     return removed;
 }
 
+void GeoFeatureGroupExtension::extensionOnChanged(const Property* p) {
+        
+    //objects are only allowed in a single GeoFeatureGroup
+    if((strcmp(p->getName(), "Group")==0)) {
+     
+        bool error = false;
+        auto corrected = Group.getValues();
+        for(auto obj : Group.getValues()) {
+            
+            //we have already set the obj into the group, so in a case of multiple groups getGroupOfObject
+            //would return anyone of it and hence it is possible that we miss an error. We need a custom check
+            auto list = obj->getInList();
+            for (auto in : list) {
+                if(in->hasExtension(App::GeoFeatureGroupExtension::getExtensionClassTypeId()) &&
+                    in != getExtendedObject()) {
+                    error = true;
+                    corrected.erase(std::remove(corrected.begin(), corrected.end(), obj), corrected.end());
+                }
+            }
+        }
+        
+        //if an error was found we need to correct the values and inform the user
+        if(error) {
+            Group.setValues(corrected);
+            throw Base::Exception("Object can only be in a single GeoFeatureGroup");
+        }
+    }
+    
+    App::GroupExtension::extensionOnChanged(p);
+}
+
+
 std::vector< DocumentObject* > GeoFeatureGroupExtension::getObjectsFromLinks(DocumentObject* obj) {
 
     //we get all linked objects. We can't use outList() as this includes the links from expressions

src/App/GeoFeatureGroupExtension.h

@@ -68,6 +68,8 @@ public:
     /// Constructor
     GeoFeatureGroupExtension(void);
     virtual ~GeoFeatureGroupExtension();
+    
+    virtual void extensionOnChanged(const Property* p);
 
     /** Returns the geo feature group which contains this object.
      * In case this object is not part of any geoFeatureGroup 0 is returned.

src/App/GroupExtension.cpp

@@ -272,7 +272,6 @@ void GroupExtension::extensionOnChanged(const Property* p) {
                     in != getExtendedObject()) {
                     error = true;
                     corrected.erase(std::remove(corrected.begin(), corrected.end(), obj), corrected.end());
-                    break;
                 }
             }
         }

src/Mod/Test/Document.py

@@ -873,19 +873,17 @@ class UndoRedoCases(unittest.TestCase):
     self.failUnless(prt1.hasObject(obj1)==False)
     self.failUnless(prt2.hasObject(grp2))
     self.failUnless(prt2.hasObject(obj1))
-       
-    #to test: try add obj to second group by .Group = []
-    grp = prt1.Group
-    grp.append(grp2)
-    
     try:
-        prt1.Group=grp
-        self.Doc.recompute()
+        grp = prt1.Group
+        grp.append(obj1)
+        prt1.Group = grp
     except:
-        pass
+        grp.remove(obj1)
+        self.failUnless(prt1.Group == grp)
     else:
-        self.fail("No exception at cross geofeaturegroup links")
-    
+        self.fail("No exception thrown when object is in multiple Groups")
+          
+    #it is not allowed to be in 2 Groups
     prt2.addObject(grp1)
     grp = grp1.Group
     grp.append(obj1)
@@ -896,7 +894,17 @@ class UndoRedoCases(unittest.TestCase):
     else:
         self.fail("No exception thrown when object is in multiple Groups")
    
-        
+    #to test: try add obj to second group by .Group = []
+    grp = prt1.Group
+    grp.append(grp2)
+    
+    try:
+        prt1.Group=grp
+        self.Doc.recompute()
+    except:
+        pass
+    else:
+        self.fail("No exception at cross geofeaturegroup links") 
 
   def tearDown(self):
     # closing doc