def test_setting_use_cache_does_cache(self):
# Given
pa = self._make_random_parray('pa1', 3)
pa.h[:] = 1.0
nnps = LinkedListNNPS(dim=3, particles=[pa], cache=False)
n = pa.get_number_of_particles()
# When
nnps.set_use_cache(True)
nbrs = UIntArray()
nnps.set_context(0, 0)
for i in range(n):
nnps.get_nearest_particles(0, 0, i, nbrs)
# Then
self.assertEqual(nbrs.length, n)
# Find the length of all cached neighbors,
# in this case, each particle has n neighbors,
# so we should have n*n neighbors in all.
total_length = sum(x.length for x in nnps.cache[0]._neighbor_arrays)
self.assertEqual(total_length, n * n)
