Pickle

nutils/function.py

@@ -2736,6 +2736,13 @@ def __init__(self, ndofs: int, nelems: int, index: Array, coords: Array) -> None
         assert self._arg_coeffs_evaluable.ndim == 2
         assert not evaluable._certainly_different(self._arg_dofs_evaluable.shape[0], self._arg_coeffs_evaluable.shape[0])
 
+    def __getstate__(self):
+        state = self.__dict__.copy()
+        state.pop('_arg_dofs', None)
+        state.pop('_arg_coeffs', None)
+        state.pop('_arg_ndofs', None)
+        return state
+
     @cached_property
     def _arg_dofs(self):
         return evaluable.compile(self._arg_dofs_evaluable)

tests/test_function.py

@@ -1321,6 +1321,19 @@ def test_lower(self):
                     value = numpy.tile(value, (points.npoints, 1))
                 self.assertAllAlmostEqual(value, self.checkeval(ielem, points))
 
+    def test_pickle(self):
+        # touch all unpicklable cached properties
+        _arg_dofs = self.basis._arg_dofs
+        _arg_coeffs = self.basis._arg_coeffs
+        _arg_ndofs = self.basis._arg_ndofs
+        # try pickle, unpickle
+        s = pickle.dumps(self.basis)
+        basis = pickle.loads(s)
+        # confirm that all cached properties is still as they were
+        self.assertEqual(_arg_dofs, self.basis._arg_dofs)
+        self.assertEqual(_arg_coeffs, self.basis._arg_coeffs)
+        self.assertEqual(_arg_ndofs, self.basis._arg_ndofs)
+
 
 class PlainBasis(CommonBasis, TestCase):