From e12f7c9041281ca37a1bc9f2ac54bd6870f2e180 Mon Sep 17 00:00:00 2001
From: Patrick Shriwise <pshriwise@gmail.com>
Date: Thu, 31 Jan 2019 10:30:38 -0600
Subject: [PATCH] Adding reset before exporting a geometry.

---
 openmc/geometry.py  | 5 +++++
 openmc/geomtrack.py | 6 ++++++
 2 files changed, 11 insertions(+)

diff --git a/openmc/geometry.py b/openmc/geometry.py
index 260bb9e83c..61032d9a80 100644
--- a/openmc/geometry.py
+++ b/openmc/geometry.py
@@ -10,6 +10,7 @@ import openmc
 import openmc._xml as xml
 from openmc.checkvalue import check_type
 
+from .geomtrack import ElementTracker
 
 class Geometry(object):
     """Geometry representing a collection of surfaces, cells, and universes.
@@ -87,6 +88,10 @@ class Geometry(object):
 
         """
         # Create XML representation
+
+        et = ElementTracker()
+        et.reset()
+
         root_element = ET.Element("geometry")
         self.root_universe.create_xml_subelement(root_element)
 
diff --git a/openmc/geomtrack.py b/openmc/geomtrack.py
index bf3fcac121..f2230ce7d3 100644
--- a/openmc/geomtrack.py
+++ b/openmc/geomtrack.py
@@ -29,6 +29,12 @@ class ElementTracker:
         def add_universe(self, universe_id):
             self.update("universe", universe_id)
 
+        def reset(self):
+            self.cells = set()
+            self.surfaces = set()
+            self.lattices = set()
+            self.universes = set()
+
     instance = None
 
     def __init__(self):