Trim whitespace when setting display names (#16031)

3 files changed, 14 insertions, 1 deletions

diff --git a/changelog.d/16031.bugfix b/changelog.d/16031.bugfix
new file mode 100644

index 0000000000..e48bf3975c
--- /dev/null
+++ b/changelog.d/16031.bugfix
@@ -0,0 +1 @@
+Remove leading and trailing spaces when setting a display name.
diff --git a/synapse/handlers/profile.py b/synapse/handlers/profile.py

index c7fe101cd9..c2109036ec 100644
--- a/synapse/handlers/profile.py
+++ b/synapse/handlers/profile.py
@@ -163,7 +163,7 @@ class ProfileHandler:
                 400, "Displayname is too long (max %i)" % (MAX_DISPLAYNAME_LEN,)
             )
 
-        displayname_to_set: Optional[str] = new_displayname
+        displayname_to_set: Optional[str] = new_displayname.strip()
         if new_displayname == "":
             displayname_to_set = None
 
diff --git a/tests/rest/client/test_profile.py b/tests/rest/client/test_profile.py

index 27c93ad761..ecae092b47 100644
--- a/tests/rest/client/test_profile.py
+++ b/tests/rest/client/test_profile.py
@@ -68,6 +68,18 @@ class ProfileTestCase(unittest.HomeserverTestCase):
         res = self._get_displayname()
         self.assertEqual(res, "test")
 
+    def test_set_displayname_with_extra_spaces(self) -> None:
+        channel = self.make_request(
+            "PUT",
+            "/profile/%s/displayname" % (self.owner,),
+            content={"displayname": "  test  "},
+            access_token=self.owner_tok,
+        )
+        self.assertEqual(channel.code, 200, channel.result)
+
+        res = self._get_displayname()
+        self.assertEqual(res, "test")
+
     def test_set_displayname_noauth(self) -> None:
         channel = self.make_request(
             "PUT",