def test_aggregate_host_add_duplicate_works(self):
     """Ensure we can add host to distinct aggregates."""
     ctxt = context.get_admin_context()
     r1 = _create_aggregate_with_hosts(context=ctxt, metadata=None)
     r2 = _create_aggregate_with_hosts(
         ctxt, values={"name": "fake_aggregate2", "availability_zone": "fake_avail_zone2"}, metadata=None
     )
     h1 = db.aggregate_host_get_all(ctxt, r1.id)
     h2 = db.aggregate_host_get_all(ctxt, r2.id)
     self.assertEqual(h1, h2)

 def test_aggregate_host_delete(self):
     """Ensure we can add host to the aggregate."""
     ctxt = context.get_admin_context()
     result = _create_aggregate_with_hosts(context=ctxt, metadata=None)
     db.aggregate_host_delete(ctxt, result.id, _get_fake_aggr_hosts()[0])
     expected = db.aggregate_host_get_all(ctxt, result.id)
     self.assertEqual(0, len(expected))

 def test_aggregate_host_add_deleted(self):
     """Ensure we can add a host that was previously deleted."""
     ctxt = context.get_admin_context()
     result = _create_aggregate_with_hosts(context=ctxt, metadata=None)
     host = _get_fake_aggr_hosts()[0]
     db.aggregate_host_delete(ctxt, result.id, host)
     db.aggregate_host_add(ctxt, result.id, host)
     expected = db.aggregate_host_get_all(ctxt, result.id)
     self.assertEqual(len(expected), 1)