Extra generic errors for Scene, Groups and Metaballs to raise errors when trying to do anything with a python objects thats had its data removed in Blender.

Added to existing scn.objects
scn.objects.active    (get/set the active object for the scene)

scn.objects.selected    - an iterator that only uses selected objects
scn.objects.context    - an iterator on objects in the user context (visible in the current 3d views layer and selected)
These are the same type as scn.objects but .add() .remove() .new() .active etc raise errors. so scn.objects.selected.add() will raise an error.

Made nested loops possible with scn.objects, metaball.elements and ob.modifiers, by initializing the iter value as NULL and creating copys of the pyobject when _getIter() is called if ->iter is not NULL.
This is how pythons xrange() works.

1 files changed, 82 insertions, 72 deletions

diff --git a/source/blender/python/api2_2x/Group.c b/source/blender/python/api2_2x/Group.c
index fae3c11db5a..080520e3a9d 100755
--- a/source/blender/python/api2_2x/Group.c
+++ b/source/blender/python/api2_2x/Group.c
@@ -48,6 +48,9 @@
 #include "Object.h"
 #include "gen_utils.h"
 
+/* checks for the group being removed */
+#define GROUP_DEL_CHECK_PY(bpy_group) if (!(bpy_group->group)) return ( EXPP_ReturnPyObjError( PyExc_RuntimeError, "Group has been removed" ) )
+#define GROUP_DEL_CHECK_INT(bpy_group) if (!(bpy_group->group)) return ( EXPP_ReturnIntError( PyExc_RuntimeError, "Group has been removed" ) )
 
 /*****************************************************************************/
 /* Python API function prototypes for the Blender module.		 */
@@ -56,6 +59,8 @@ static PyObject *M_Group_New( PyObject * self, PyObject * args );
 PyObject *M_Group_Get( PyObject * self, PyObject * args );
 PyObject *M_Group_Unlink( PyObject * self, PyObject * args );
 
+/* internal */
+static PyObject *GroupObSeq_CreatePyObject( BPy_Group *self, GroupObject *iter );
 
 /*****************************************************************************/
 /* Python method structure definition for Blender.Object module:	 */
@@ -86,41 +91,38 @@ static PyMethodDef BPy_Group_methods[] = {
 
 static PyObject *BPy_Group_copy( BPy_Group * self )
 {
+	BPy_Group *py_group;	/* for Group Data object wrapper in Python */
+	struct Group *bl_group;
+	GroupObject *group_ob, *group_ob_new; /* Group object, copied and added to the groups */
 	
-	if( !(self->group) ) {
-		return EXPP_ReturnPyObjError( PyExc_RuntimeError,
-					      "Blender Group was deleted!" );
-	} else {
-		BPy_Group *py_group;	/* for Group Data object wrapper in Python */
-		struct Group *bl_group;
-		GroupObject *group_ob, *group_ob_new; /* Group object, copied and added to the groups */
-		
-		bl_group= add_group();
-		
-		if( bl_group )		/* now create the wrapper grp in Python */
-			py_group = ( BPy_Group * ) Group_CreatePyObject( bl_group );
-		else
-			return ( EXPP_ReturnPyObjError( PyExc_RuntimeError,
-							"couldn't create Group Data in Blender" ) );
-		
-		rename_id( &bl_group->id, self->group->id.name + 2 );
-		
-		
-		/* user count be incremented in Group_CreatePyObject */
-		bl_group->id.us = 0;
-		
-		/* Now add the objects to the group */
-		group_ob= self->group->gobject.first;
-		while(group_ob) {
-			/* save time by not using */
-			group_ob_new= MEM_callocN(sizeof(GroupObject), "groupobject");
-			group_ob_new->ob= group_ob->ob;
-			BLI_addtail( &bl_group->gobject, group_ob_new);
-			group_ob= group_ob->next;
-		}
-		
-		return ( PyObject * ) py_group;
+	GROUP_DEL_CHECK_PY(self);
+	
+	bl_group= add_group();
+	
+	if( bl_group )		/* now create the wrapper grp in Python */
+		py_group = ( BPy_Group * ) Group_CreatePyObject( bl_group );
+	else
+		return ( EXPP_ReturnPyObjError( PyExc_RuntimeError,
+						"couldn't create Group Data in Blender" ) );
+	
+	rename_id( &bl_group->id, self->group->id.name + 2 );
+	
+	
+	/* user count be incremented in Group_CreatePyObject */
+	bl_group->id.us = 0;
+	
+	/* Now add the objects to the group */
+	group_ob= self->group->gobject.first;
+	while(group_ob) {
+		/* save time by not using */
+		group_ob_new= MEM_callocN(sizeof(GroupObject), "groupobject");
+		group_ob_new->ob= group_ob->ob;
+		BLI_addtail( &bl_group->gobject, group_ob_new);
+		group_ob= group_ob->next;
 	}
+	
+	return ( PyObject * ) py_group;
+	
 }
 
 
@@ -131,9 +133,7 @@ static PyObject *BPy_Group_copy( BPy_Group * self )
  ************************************************************************/
 static PyObject *Group_getObjects( BPy_Group * self )
 {
-	BPy_GroupObSeq *seq = PyObject_NEW( BPy_GroupObSeq, &GroupObSeq_Type);
-	seq->bpygroup = self; Py_INCREF(self);
-	return (PyObject *)seq;
+	return GroupObSeq_CreatePyObject(self, NULL);
 }
 
 
@@ -158,6 +158,8 @@ static int Group_setObjects( BPy_Group * self, PyObject * args )
 	Object *blen_ob;
 	group= self->group;
 	
+	GROUP_DEL_CHECK_INT(self);
+	
 	if( PyList_Check( args ) ) {
 		if( EXPP_check_sequence_consistency( args, &Object_Type ) != 1)
 			return ( EXPP_ReturnIntError( PyExc_TypeError, 
@@ -170,11 +172,6 @@ static int Group_setObjects( BPy_Group * self, PyObject * args )
 			blen_ob= ((BPy_Object *)PyList_GET_ITEM( args, i ))->object;
 			add_to_group_wraper(group, blen_ob);
 		}
-	/*
-	} else if( args->ob_type == &GroupObSeq_Type ) {
-	*/
-		/* todo, handle sequences here */
-	
 	} else if (PyIter_Check(args)) {
 		PyObject *iterator = PyObject_GetIter(args);
 		PyObject *item;
@@ -224,9 +221,7 @@ static int Group_setName( BPy_Group * self, PyObject * value )
 	char *name = NULL;
 	char buf[21];
 	
-	if( !(self->group) )
-		return EXPP_ReturnIntError( PyExc_RuntimeError,
-					      "Blender Group was deleted!" );
+	GROUP_DEL_CHECK_INT(self);
 	
 	name = PyString_AsString ( value );
 	if( !name )
@@ -244,9 +239,7 @@ static int Group_setName( BPy_Group * self, PyObject * value )
 static PyObject *Group_getName( BPy_Group * self, PyObject * args )
 {
 	PyObject *attr;
-	if( !(self->group) )
-		return ( EXPP_ReturnPyObjError( PyExc_RuntimeError,
-					      "Blender Group was deleted!" ) );
+	GROUP_DEL_CHECK_PY(self);
 	
 	attr = PyString_FromString( self->group->id.name + 2 );
 
@@ -488,11 +481,10 @@ PyObject *M_Group_Unlink( PyObject * self, PyObject * args )
 						"expected a group" ) );
 	
 	pygrp= (BPy_Group *)pyob;
-	group= pygrp->group;
 	
-	if( !group )
-		return ( EXPP_ReturnPyObjError( PyExc_RuntimeError,
-					      "Blender Group was deleted!" ) );
+	GROUP_DEL_CHECK_PY(pygrp);
+	
+	group= pygrp->group;
 	
 	pygrp->group= NULL;
 	free_group(group);
@@ -625,6 +617,9 @@ static int Group_compare( BPy_Group * a, BPy_Group * b )
 /*****************************************************************************/
 static PyObject *Group_repr( BPy_Group * self )
 {
+	if (!self->group)
+		return PyString_FromString( "[Group - Removed]" );
+	
 	return PyString_FromFormat( "[Group \"%s\"]",
 				    self->group->id.name + 2 );
 }
@@ -639,12 +634,34 @@ static PyObject *Group_repr( BPy_Group * self )
  * create a thin GroupOb object
  */
 
-static PyObject *GroupObSeq_CreatePyObject( Group *group, int i )
+static PyObject *GroupObSeq_CreatePyObject( BPy_Group *self, GroupObject *iter )
+{
+	BPy_GroupObSeq *seq = PyObject_NEW( BPy_GroupObSeq, &GroupObSeq_Type);
+	seq->bpygroup = self; Py_INCREF(self);
+	seq->iter= iter;
+	return (PyObject *)seq;
+}
+
+
+static int GroupObSeq_len( BPy_GroupObSeq * self )
+{
+	GROUP_DEL_CHECK_INT(self->bpygroup);
+	return BLI_countlist( &( self->bpygroup->group->gobject ) );
+}
+
+/*
+ * retrive a single GroupOb from somewhere in the GroupObex list
+ */
+
+static PyObject *GroupObSeq_item( BPy_GroupObSeq * self, int i )
 {
+	Group *group= self->bpygroup->group;
 	int index=0;
 	PyObject *bpy_obj;
 	GroupObject *gob;
 	
+	GROUP_DEL_CHECK_PY(self->bpygroup);
+	
 	for (gob= group->gobject.first; gob && i!=index; gob= gob->next, index++) {}
 	
 	if (!(gob))
@@ -658,21 +675,7 @@ static PyObject *GroupObSeq_CreatePyObject( Group *group, int i )
 				"PyObject_New() failed" );
 
 	return (PyObject *)bpy_obj;
-}
-
-
-static int GroupObSeq_len( BPy_GroupObSeq * self )
-{
-	return BLI_countlist( &( self->bpygroup->group->gobject ) );
-}
-
-/*
- * retrive a single GroupOb from somewhere in the GroupObex list
- */
-
-static PyObject *GroupObSeq_item( BPy_GroupObSeq * self, int i )
-{
-	return GroupObSeq_CreatePyObject( self->bpygroup->group, i );
+	
 }
 
 static PySequenceMethods GroupObSeq_as_sequence = {
@@ -698,8 +701,14 @@ static PySequenceMethods GroupObSeq_as_sequence = {
 
 static PyObject *GroupObSeq_getIter( BPy_GroupObSeq * self )
 {
-	self->iter = self->bpygroup->group->gobject.first;
-	return EXPP_incr_ret ( (PyObject *) self );
+	GROUP_DEL_CHECK_PY(self->bpygroup);
+	
+	if (!self->iter) {
+		self->iter = self->bpygroup->group->gobject.first;
+		return EXPP_incr_ret ( (PyObject *) self );
+	} else {
+		return GroupObSeq_CreatePyObject(self->bpygroup->group, self->bpygroup->group->gobject.first);
+	}
 }
 
 /*
@@ -724,6 +733,9 @@ static PyObject *GroupObSeq_add( BPy_GroupObSeq * self, PyObject *args )
 	PyObject *pyobj;
 	Object *blen_ob;
 	Base *base= NULL;
+	
+	GROUP_DEL_CHECK_PY(self->bpygroup);
+	
 	if( !PyArg_ParseTuple( args, "O!", &Object_Type, &pyobj ) )
 		return ( EXPP_ReturnPyObjError( PyExc_TypeError,
 				"expected a python object as an argument" ) );
@@ -745,9 +757,7 @@ static PyObject *GroupObSeq_remove( BPy_GroupObSeq * self, PyObject *args )
 	Object *blen_ob;
 	Base *base= NULL;
 	
-	if( !(self->bpygroup->group) )
-		return (EXPP_ReturnPyObjError( PyExc_RuntimeError,
-					      "Blender Group was deleted!" ));
+	GROUP_DEL_CHECK_PY(self->bpygroup);
 	
 	if( !PyArg_ParseTuple( args, "O!", &Object_Type, &pyobj ) )
 		return ( EXPP_ReturnPyObjError( PyExc_TypeError,