From 95057442914b2d36d87809dd23e55c724cd44fc6 Mon Sep 17 00:00:00 2001
From: Sterling Harper <smharper@mit.edu>
Date: Sat, 9 Jan 2016 23:44:26 -0500
Subject: [PATCH] Fix void distribmats

---
 openmc/universe.py                       | 13 +++++++++----
 src/summary.F90                          | 14 +++++++++++---
 tests/test_distribmat/inputs_true.dat    |  2 +-
 tests/test_distribmat/results_true.dat   |  4 ++--
 tests/test_distribmat/test_distribmat.py |  5 +----
 5 files changed, 24 insertions(+), 14 deletions(-)

diff --git a/openmc/universe.py b/openmc/universe.py
index 2fa535265c..048b6a0e9f 100644
--- a/openmc/universe.py
+++ b/openmc/universe.py
@@ -113,8 +113,11 @@ class Cell(object):
             string += '{0: <16}{1}{2}\n'.format('\tMaterial', '=\t',
                                                 self._fill._id)
         elif isinstance(self._fill, Iterable):
-            string += ('{0: <16}{1}'.format('\tMaterial', '=\t')
-                 + '[' + ', '.join([str(m.id) for m in self.fill]) + ']\n')
+            string += '{0: <16}{1}'.format('\tMaterial', '=\t')
+            string += '['
+            string += ', '.join(['void' if m == 'void' else str(m.id)
+                                 for m in self.fill])
+            string += ']\n'
         elif isinstance(self._fill, (Universe, Lattice)):
             string += '{0: <16}{1}{2}\n'.format('\tFill', '=\t',
                                                 self._fill._id)
@@ -209,7 +212,8 @@ class Cell(object):
             self._type = 'normal'
 
         elif isinstance(fill, Iterable):
-            cv.check_type('cell.fill', fill, Iterable, openmc.Material)
+            cv.check_type('cell.fill', fill, Iterable,
+                          (openmc.Material, basestring))
             self._type = 'normal'
 
         elif isinstance(fill, Universe):
@@ -402,7 +406,8 @@ class Cell(object):
             element.set("material", str(self._fill._id))
 
         elif isinstance(self._fill, Iterable):
-            element.set("material", ' '.join([str(m.id) for m in self.fill]))
+            element.set("material", ' '.join([m if m == 'void' else str(m.id)
+                                              for m in self.fill]))
 
         elif isinstance(self._fill, (Universe, Lattice)):
             element.set("fill", str(self._fill._id))
diff --git a/src/summary.F90 b/src/summary.F90
index deccaddf59..c06d2549c2 100644
--- a/src/summary.F90
+++ b/src/summary.F90
@@ -152,12 +152,20 @@ contains
       case (CELL_NORMAL)
         call write_dataset(cell_group, "fill_type", "normal")
         if (size(c % material) == 1) then
-          call write_dataset(cell_group, "material", &
-               materials(c % material(1)) % id)
+          if (c % material(1) == MATERIAL_VOID) then
+            call write_dataset(cell_group, "material", MATERIAL_VOID)
+          else
+            call write_dataset(cell_group, "material", &
+                 materials(c % material(1)) % id)
+          end if
         else
           allocate(cell_materials(size(c % material)))
           do j = 1, size(c % material)
-            cell_materials(j) = materials(c % material(j)) % id
+            if (c % material(j) == MATERIAL_VOID) then
+              cell_materials(j) = MATERIAL_VOID
+            else
+              cell_materials(j) = materials(c % material(j)) % id
+            end if
           end do
           call write_dataset(cell_group, "material", cell_materials)
           deallocate(cell_materials)
diff --git a/tests/test_distribmat/inputs_true.dat b/tests/test_distribmat/inputs_true.dat
index 48044e2872..0fb8cc8bf8 100644
--- a/tests/test_distribmat/inputs_true.dat
+++ b/tests/test_distribmat/inputs_true.dat
@@ -1 +1 @@
-24a3537446feafcf79fc84d268b43130e9521ad7cccfcf733ba35ca50bf3c644e0b8e91bfdef7bdb4073783197cfdd730d1e459fc622aa3ce6dcf3143c805a1f
\ No newline at end of file
+bdc2acd3a4f5078c61d7cb83ff30e07b76c89b21d8131c1b0ce86a43156da7bd0b9ebb5d6acc0b98a7d8128667f99403ef12a6d76ed2ec6cb187810222e4f6b3
\ No newline at end of file
diff --git a/tests/test_distribmat/results_true.dat b/tests/test_distribmat/results_true.dat
index 5e93e4e473..70464fbc6c 100644
--- a/tests/test_distribmat/results_true.dat
+++ b/tests/test_distribmat/results_true.dat
@@ -1,9 +1,9 @@
 k-combined:
-1.433669E+00 7.069157E-03
+1.309285E+00 1.263629E-02
 Cell
 	ID             =	11
 	Name           =	
-	Material       =	[2, 3, 2, 2]
+	Material       =	[2, 3, void, 2]
 	Region         =	-10000
 	Rotation       =	None
 	Translation    =	None
diff --git a/tests/test_distribmat/test_distribmat.py b/tests/test_distribmat/test_distribmat.py
index 61e40e64c6..f0d09e963a 100644
--- a/tests/test_distribmat/test_distribmat.py
+++ b/tests/test_distribmat/test_distribmat.py
@@ -44,7 +44,7 @@ class DistribmatTestHarness(PyAPITestHarness):
         r0 = openmc.ZCylinder(R=0.3)
         c11 = openmc.Cell(cell_id=11)
         c11.region = -r0
-        c11.fill = [dense_fuel, light_fuel] + [dense_fuel]*2
+        c11.fill = [dense_fuel, light_fuel, 'void', dense_fuel]
         c12 = openmc.Cell(cell_id=12)
         c12.region = +r0
         c12.fill = moderator
@@ -122,9 +122,6 @@ class DistribmatTestHarness(PyAPITestHarness):
         outstr += str(su.get_cell_by_id(11))
         return outstr
 
-#    def _cleanup(self):
-#        return None
-
 
 if __name__ == '__main__':
     harness = DistribmatTestHarness('statepoint.5.*')