From 5817a42bf0384ae2beb9c83552eefd03c453646c Mon Sep 17 00:00:00 2001
From: Karl Hobley <karl@torchbox.com>
Date: Wed, 30 Jan 2019 08:18:34 +0000
Subject: [PATCH] Fix new flake8 error F632

---
 wagtail/core/query.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/wagtail/core/query.py b/wagtail/core/query.py
index add03e9e1..20bea63ea 100644
--- a/wagtail/core/query.py
+++ b/wagtail/core/query.py
@@ -311,7 +311,7 @@ class PageQuerySet(SearchableQuerySetMixin, TreeQuerySet):
         if extra_chars != 0:
             common_parent_path = common_parent_path[:-extra_chars]
 
-        if common_parent_path is '':
+        if common_parent_path == '':
             # This should only happen when there are multiple trees,
             # a situation that Wagtail does not support;
             # or when the root node itself is part of the queryset.