From 9f2fd29c14616b64a07495a74847004e683ead73 Mon Sep 17 00:00:00 2001
From: Matthew Hodgson <matthew@matrix.org>
Date: Fri, 4 May 2018 02:11:22 +0100
Subject: [PATCH] fix double negative

---
 synapse/handlers/register.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/synapse/handlers/register.py b/synapse/handlers/register.py
index e308fcbb45..523cb67536 100644
--- a/synapse/handlers/register.py
+++ b/synapse/handlers/register.py
@@ -170,7 +170,7 @@ class RegistrationHandler(BaseHandler):
                 admin=admin,
             )
 
-            if display_name is not None:
+            if display_name is None:
                 display_name = (
                     # If the user was a guest then they already have a profile
                     None if was_guest else user.localpart