Merge pull request #2148 from devitocodes/fix-pickle-alias-sf

compiler: Fix pickling of aliasing SparseFunction

devito/types/sparse.py

@@ -488,7 +488,10 @@ def coordinates(self):
 
     @property
     def coordinates_data(self):
-        return self.coordinates.data.view(np.ndarray)
+        try:
+            return self.coordinates.data.view(np.ndarray)
+        except AttributeError:
+            return None
 
     @cached_property
     def _point_symbols(self):

tests/test_pickle.py

@@ -393,6 +393,25 @@ def test_receiver(self, pickle):
         assert np.all(new_rec.data == 1)
         assert np.all(new_rec.coordinates.data == [[0.], [1.], [2.]])
 
+    def test_alias_sparse_function(self, pickle):
+        grid = Grid(shape=(3,))
+        sf = SparseFunction(name='sf', grid=grid, npoint=3, space_order=2,
+                            coordinates=[(0.,), (1.,), (2.,)])
+        sf.data[0] = 1.
+
+        # Create alias
+        f0 = sf._rebuild(name='f0', alias=True)
+
+        pkl_f0 = pickle.dumps(f0)
+        new_f0 = pickle.loads(pkl_f0)
+
+        assert f0.data is None and new_f0.data is None
+        assert f0.coordinates.data is None and new_f0.coordinates.data is None
+
+        assert sf.space_order == f0.space_order == new_f0.space_order
+        assert sf.dtype == f0.dtype == new_f0.dtype
+        assert sf.npoint == f0.npoint == new_f0.npoint
+
 
 @pytest.mark.parametrize('pickle', [pickle0, pickle1])
 class TestOperator(object):