From 94082a2f73e4006eba5c872844d9660a281f9da6 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Stefan=20Tr=C3=B6ger?= <stefantroeger@gmx.net>
Date: Thu, 9 Feb 2017 22:37:41 +0100
Subject: [PATCH] Group: ensure single group only

---
 src/App/GeoFeatureGroupExtension.cpp |  2 --
 src/App/GeoFeatureGroupExtension.h   |  1 +
 src/App/GroupExtension.cpp           | 24 ++++++++++++++++++++++++
 src/App/GroupExtension.h             |  2 ++
 src/Mod/Test/Document.py             |  3 +++
 5 files changed, 30 insertions(+), 2 deletions(-)

diff --git a/src/App/GeoFeatureGroupExtension.cpp b/src/App/GeoFeatureGroupExtension.cpp
index 10425f6b13..0b7382f905 100644
--- a/src/App/GeoFeatureGroupExtension.cpp
+++ b/src/App/GeoFeatureGroupExtension.cpp
@@ -281,8 +281,6 @@ std::vector< DocumentObject* > GeoFeatureGroupExtension::getCSRelevantLinks(Docu
     return result;
 }
 
-
-
 // Python feature ---------------------------------------------------------
 
 namespace App {
diff --git a/src/App/GeoFeatureGroupExtension.h b/src/App/GeoFeatureGroupExtension.h
index a9b5d0ad4d..d4ec727b67 100644
--- a/src/App/GeoFeatureGroupExtension.h
+++ b/src/App/GeoFeatureGroupExtension.h
@@ -111,6 +111,7 @@ public:
     /// obj and from obj excluding expressions and stopping the recursion at other geofeaturegroups. 
     /// The result is the combination of CSOutList and CSInList.
     static std::vector<App::DocumentObject*> getCSRelevantLinks(App::DocumentObject* obj);
+    
 private:
     Base::Placement recursiveGroupPlacement(GeoFeatureGroupExtension* group);
     static std::vector<App::DocumentObject*> getObjectsFromLinks(App::DocumentObject*);
diff --git a/src/App/GroupExtension.cpp b/src/App/GroupExtension.cpp
index 1645f82975..bd092dd8c1 100644
--- a/src/App/GroupExtension.cpp
+++ b/src/App/GroupExtension.cpp
@@ -243,6 +243,30 @@ PyObject* GroupExtension::getExtensionPyObject(void) {
     return Py::new_reference_to(ExtensionPythonObject);
 }
 
+void GroupExtension::extensionOnChanged(const Property* p) {
+    
+    //we need to remove all object that have  other parent geofeature groups
+    if(strcmp(p->getName(), "Group")==0) {
+     
+        bool error = false;
+        auto corrected = Group.getValues();
+        for(auto obj : Group.getValues()) {
+            
+            auto grp = GroupExtension::getGroupOfObject(obj);
+            if(grp && (grp != getExtendedObject())) {
+                error = true;
+                corrected.erase(std::remove(corrected.begin(), corrected.end(), obj), corrected.end());
+            }
+        }  
+        if(error) {
+            Group.setValues(corrected);
+            throw Base::Exception("Object can only be in a single Group");
+        }
+    }
+    
+    App::Extension::extensionOnChanged(p);
+}
+
 
 namespace App {
 EXTENSION_PROPERTY_SOURCE_TEMPLATE(App::GroupExtensionPython, App::GroupExtension)
diff --git a/src/App/GroupExtension.h b/src/App/GroupExtension.h
index 02b24f05c0..0dd0e91413 100644
--- a/src/App/GroupExtension.h
+++ b/src/App/GroupExtension.h
@@ -100,6 +100,8 @@ public:
     
     virtual PyObject* getExtensionPyObject(void);
 
+    virtual void extensionOnChanged(const Property* p) override;
+    
     /// Properties
     PropertyLinkList Group;
 
diff --git a/src/Mod/Test/Document.py b/src/Mod/Test/Document.py
index f8fa39d39b..5f07cebb5d 100644
--- a/src/Mod/Test/Document.py
+++ b/src/Mod/Test/Document.py
@@ -869,6 +869,9 @@ class UndoRedoCases(unittest.TestCase):
     #adding the object to a geofeaturegroup, but not its group, should handle it automatically when used 
     #addObject
     
+    #to test: try add obj to second group, once by addObject, once by .Group = []
+    
+    
 
   def tearDown(self):
     # closing doc