'Test trimming snapshots with the default arguments, which should
keep all monthly backups forever. The result of this test should
be that nothing is deleted.'

def test_trim_defaults(self):

    orig = {'get_all_snapshots': self.ec2.get_all_snapshots, 'delete_snapshot': self.ec2.delete_snapshot}
    snaps = self._get_snapshots()
    self.ec2.get_all_snapshots = MagicMock(return_value=snaps)
    self.ec2.delete_snapshot = MagicMock()
    self.ec2.trim_snapshots()
    self.assertEqual(True, self.ec2.get_all_snapshots.called)
    self.assertEqual(False, self.ec2.delete_snapshot.called)
    self.ec2.get_all_snapshots = orig['get_all_snapshots']
    self.ec2.delete_snapshot = orig['delete_snapshot']
