Remove redundant types from comments. (#14412)

Remove type hints from comments which have been added
as Python type hints. This helps avoid drift between comments
and reality, as well as removing redundant information.

Also adds some missing type hints which were simple to fill in.

5 files changed, 30 insertions, 26 deletions

diff --git a/tests/http/__init__.py b/tests/http/__init__.py
index e74f7f5b48..093537adef 100644
--- a/tests/http/__init__.py
+++ b/tests/http/__init__.py
@@ -13,6 +13,7 @@
 # limitations under the License.
 import os.path
 import subprocess
+from typing import List
 
 from zope.interface import implementer
 
@@ -70,14 +71,14 @@ subjectAltName = %(sanentries)s
 """
 
 
-def create_test_cert_file(sanlist):
+def create_test_cert_file(sanlist: List[bytes]) -> str:
     """build an x509 certificate file
 
     Args:
-        sanlist: list[bytes]: a list of subjectAltName values for the cert
+        sanlist: a list of subjectAltName values for the cert
 
     Returns:
-        str: the path to the file
+        The path to the file
     """
     global cert_file_count
     csr_filename = "server.csr"
diff --git a/tests/replication/slave/storage/test_events.py b/tests/replication/slave/storage/test_events.py
index 96f3880923..dce71f7334 100644
--- a/tests/replication/slave/storage/test_events.py
+++ b/tests/replication/slave/storage/test_events.py
@@ -143,6 +143,7 @@ class EventsWorkerStoreTestCase(BaseSlavedStoreTestCase):
         self.persist(type="m.room.create", key="", creator=USER_ID)
         self.check("get_invited_rooms_for_local_user", [USER_ID_2], [])
         event = self.persist(type="m.room.member", key=USER_ID_2, membership="invite")
+        assert event.internal_metadata.stream_ordering is not None
 
         self.replicate()
 
@@ -230,6 +231,7 @@ class EventsWorkerStoreTestCase(BaseSlavedStoreTestCase):
         j2 = self.persist(
             type="m.room.member", sender=USER_ID_2, key=USER_ID_2, membership="join"
         )
+        assert j2.internal_metadata.stream_ordering is not None
         self.replicate()
 
         expected_pos = PersistedEventPosition(
@@ -287,6 +289,7 @@ class EventsWorkerStoreTestCase(BaseSlavedStoreTestCase):
             )
         )
         self.replicate()
+        assert j2.internal_metadata.stream_ordering is not None
 
         event_source = RoomEventSource(self.hs)
         event_source.store = self.slaved_store
@@ -336,10 +339,10 @@ class EventsWorkerStoreTestCase(BaseSlavedStoreTestCase):
 
     event_id = 0
 
-    def persist(self, backfill=False, **kwargs):
+    def persist(self, backfill=False, **kwargs) -> FrozenEvent:
         """
         Returns:
-            synapse.events.FrozenEvent: The event that was persisted.
+            The event that was persisted.
         """
         event, context = self.build_event(**kwargs)
 
diff --git a/tests/replication/test_multi_media_repo.py b/tests/replication/test_multi_media_repo.py
index 13aa5eb51a..96cdf2c45b 100644
--- a/tests/replication/test_multi_media_repo.py
+++ b/tests/replication/test_multi_media_repo.py
@@ -15,8 +15,9 @@ import logging
 import os
 from typing import Optional, Tuple
 
+from twisted.internet.interfaces import IOpenSSLServerConnectionCreator
 from twisted.internet.protocol import Factory
-from twisted.protocols.tls import TLSMemoryBIOFactory
+from twisted.protocols.tls import TLSMemoryBIOFactory, TLSMemoryBIOProtocol
 from twisted.web.http import HTTPChannel
 from twisted.web.server import Request
 
@@ -102,7 +103,7 @@ class MediaRepoShardTestCase(BaseMultiWorkerStreamTestCase):
         )
 
         # fish the test server back out of the server-side TLS protocol.
-        http_server = server_tls_protocol.wrappedProtocol
+        http_server: HTTPChannel = server_tls_protocol.wrappedProtocol  # type: ignore[assignment]
 
         # give the reactor a pump to get the TLS juices flowing.
         self.reactor.pump((0.1,))
@@ -238,16 +239,15 @@ def get_connection_factory():
     return test_server_connection_factory
 
 
-def _build_test_server(connection_creator):
+def _build_test_server(
+    connection_creator: IOpenSSLServerConnectionCreator,
+) -> TLSMemoryBIOProtocol:
     """Construct a test server
 
     This builds an HTTP channel, wrapped with a TLSMemoryBIOProtocol
 
     Args:
-        connection_creator (IOpenSSLServerConnectionCreator): thing to build
-            SSL connections
-        sanlist (list[bytes]): list of the SAN entries for the cert returned
-            by the server
+        connection_creator: thing to build SSL connections
 
     Returns:
         TLSMemoryBIOProtocol
diff --git a/tests/server_notices/test_resource_limits_server_notices.py b/tests/server_notices/test_resource_limits_server_notices.py
index bf403045e9..7cbc40736c 100644
--- a/tests/server_notices/test_resource_limits_server_notices.py
+++ b/tests/server_notices/test_resource_limits_server_notices.py
@@ -11,6 +11,7 @@
 # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 # See the License for the specific language governing permissions and
 # limitations under the License.
+from typing import Tuple
 from unittest.mock import Mock
 
 from twisted.test.proto_helpers import MemoryReactor
@@ -350,14 +351,15 @@ class TestResourceLimitsServerNoticesWithRealRooms(unittest.HomeserverTestCase):
 
         self.assertTrue(notice_in_room, "No server notice in room")
 
-    def _trigger_notice_and_join(self):
+    def _trigger_notice_and_join(self) -> Tuple[str, str, str]:
         """Creates enough active users to hit the MAU limit and trigger a system notice
         about it, then joins the system notices room with one of the users created.
 
         Returns:
-            user_id (str): The ID of the user that joined the room.
-            tok (str): The access token of the user that joined the room.
-            room_id (str): The ID of the room that's been joined.
+            A tuple of:
+                user_id: The ID of the user that joined the room.
+                tok: The access token of the user that joined the room.
+                room_id: The ID of the room that's been joined.
         """
         user_id = None
         tok = None
diff --git a/tests/unittest.py b/tests/unittest.py
index 5116be338e..a120c2976c 100644
--- a/tests/unittest.py
+++ b/tests/unittest.py
@@ -360,13 +360,13 @@ class HomeserverTestCase(TestCase):
                 store.db_pool.updates.do_next_background_update(False), by=0.1
             )
 
-    def make_homeserver(self, reactor, clock):
+    def make_homeserver(self, reactor: MemoryReactor, clock: Clock):
         """
         Make and return a homeserver.
 
         Args:
             reactor: A Twisted Reactor, or something that pretends to be one.
-            clock (synapse.util.Clock): The Clock, associated with the reactor.
+            clock: The Clock, associated with the reactor.
 
         Returns:
             A homeserver suitable for testing.
@@ -426,9 +426,8 @@ class HomeserverTestCase(TestCase):
 
         Args:
             reactor: A Twisted Reactor, or something that pretends to be one.
-            clock (synapse.util.Clock): The Clock, associated with the reactor.
-            homeserver (synapse.server.HomeServer): The HomeServer to test
-            against.
+            clock: The Clock, associated with the reactor.
+            homeserver: The HomeServer to test against.
 
         Function to optionally be overridden in subclasses.
         """
@@ -452,11 +451,10 @@ class HomeserverTestCase(TestCase):
         given content.
 
         Args:
-            method (bytes/unicode): The HTTP request method ("verb").
-            path (bytes/unicode): The HTTP path, suitably URL encoded (e.g.
-            escaped UTF-8 & spaces and such).
-            content (bytes or dict): The body of the request. JSON-encoded, if
-            a dict.
+            method: The HTTP request method ("verb").
+            path: The HTTP path, suitably URL encoded (e.g. escaped UTF-8 & spaces
+                and such). content (bytes or dict): The body of the request.
+                JSON-encoded, if a dict.
             shorthand: Whether to try and be helpful and prefix the given URL
             with the usual REST API path, if it doesn't contain it.
             federation_auth_origin: if set to not-None, we will add a fake