From 9bc5b4c663ed4bb35ef74a820c108765c7ca0f67 Mon Sep 17 00:00:00 2001
From: Mark Haines <mark.haines@matrix.org>
Date: Fri, 1 Apr 2016 15:08:20 +0100
Subject: [PATCH] Assert that the step != 0

---
 synapse/storage/util/id_generators.py | 1 +
 1 file changed, 1 insertion(+)

diff --git a/synapse/storage/util/id_generators.py b/synapse/storage/util/id_generators.py
index 58ea54cf67..f69f1cdad4 100644
--- a/synapse/storage/util/id_generators.py
+++ b/synapse/storage/util/id_generators.py
@@ -67,6 +67,7 @@ class StreamIdGenerator(object):
             # ... persist event ...
     """
     def __init__(self, db_conn, table, column, extra_tables=[], step=1):
+        assert step != 0
         self._lock = threading.Lock()
         self._step = step
         self._current = _load_current_id(db_conn, table, column, step)