message_edit: Filter UserMessage better, now that mentions are unneeded.

The previous commit removed the need for `render_incoming_message` to
take a list of mentioned users; simplify the callsites accordingly.

zerver/actions/message_edit.py

@@ -3,6 +3,7 @@ from typing import Any, Dict, Iterable, List, Optional, Set, TypedDict
 
 from django.conf import settings
 from django.db import transaction
+from django.db.models import Q
 from django.utils.timezone import now as timezone_now
 from django.utils.translation import gettext as _
 from django.utils.translation import gettext_lazy
@@ -135,11 +136,6 @@ def can_edit_content_or_topic(
     return False
 
 
-class MessageUpdateUserInfoResult(TypedDict):
-    message_user_ids: Set[int]
-    mention_user_ids: Set[int]
-
-
 def maybe_send_resolve_topic_notifications(
     *,
     user_profile: UserProfile,
@@ -255,29 +251,23 @@ def send_message_moved_breadcrumbs(
             )
 
 
-def get_user_info_for_message_updates(message_id: int) -> MessageUpdateUserInfoResult:
-
+def get_mentions_for_message_updates(message_id: int) -> Set[int]:
     # We exclude UserMessage.flags.historical rows since those
     # users did not receive the message originally, and thus
     # probably are not relevant for reprocessed alert_words,
     # mentions and similar rendering features.  This may be a
     # decision we change in the future.
-    query = UserMessage.objects.filter(
-        message=message_id,
-        flags=~UserMessage.flags.historical,
-    ).values("user_profile_id", "flags")
-    rows = list(query)
-
-    message_user_ids = {row["user_profile_id"] for row in rows}
-
-    mask = UserMessage.flags.mentioned | UserMessage.flags.wildcard_mentioned
-
-    mention_user_ids = {row["user_profile_id"] for row in rows if int(row["flags"]) & mask}
-
-    return dict(
-        message_user_ids=message_user_ids,
-        mention_user_ids=mention_user_ids,
+    mentioned_user_ids = (
+        UserMessage.objects.filter(
+            message=message_id,
+            flags=~UserMessage.flags.historical,
+        )
+        .filter(
+            Q(flags__andnz=(UserMessage.flags.mentioned | UserMessage.flags.wildcard_mentioned))
+        )
+        .values_list("user_profile_id", flat=True)
     )
+    return {user_profile_id for user_profile_id in mentioned_user_ids}
 
 
 def update_user_message_flags(
@@ -973,8 +963,7 @@ def check_update_message(
             mention_backend=mention_backend,
             content=content,
         )
-        user_info = get_user_info_for_message_updates(message.id)
-        prior_mention_user_ids = user_info["mention_user_ids"]
+        prior_mention_user_ids = get_mentions_for_message_updates(message.id)
 
         # We render the message using the current user's realm; since
         # the cross-realm bots never edit messages, this should be

zerver/tests/test_message_edit.py

@@ -12,7 +12,7 @@ from zerver.actions.message_edit import (
     check_update_message,
     do_delete_messages,
     do_update_message,
-    get_user_info_for_message_updates,
+    get_mentions_for_message_updates,
 )
 from zerver.actions.reactions import do_add_reaction
 from zerver.actions.realm_settings import do_change_realm_plan_type, do_set_realm_property
@@ -730,7 +730,7 @@ class EditMessageTest(EditMessageTestCase):
         message_history = result.json()["message_history"]
         self.assert_length(message_history, 1)
 
-    def test_user_info_for_updates(self) -> None:
+    def test_mentions_for_message_updates(self) -> None:
         hamlet = self.example_user("hamlet")
         cordelia = self.example_user("cordelia")
 
@@ -742,12 +742,7 @@ class EditMessageTest(EditMessageTestCase):
             hamlet, "Denmark", content="@**Cordelia, Lear's daughter**"
         )
 
-        user_info = get_user_info_for_message_updates(msg_id)
-        message_user_ids = user_info["message_user_ids"]
-        self.assertIn(hamlet.id, message_user_ids)
-        self.assertIn(cordelia.id, message_user_ids)
-
-        mention_user_ids = user_info["mention_user_ids"]
+        mention_user_ids = get_mentions_for_message_updates(msg_id)
         self.assertEqual(mention_user_ids, {cordelia.id})
 
     def test_edit_cases(self) -> None: