mute user: Mark as read new messages.

Messages sent by muted users are marked as read
as soon as they are sent (or, more accurately,
while creating the database entries itself), regardless
of type (stream/huddle/PM).

ede73ee4cd, makes it easy to
pass a list to `do_send_messages` containing user-ids for
whom the message should be marked as read.
We add the contents of this list to the set of muter IDs,
and then pass it on to `create_user_messages`.

This benefits from the caching behaviour of `get_muting_users`
and should not cause performance issues long term.

The consequence is that messages sent by muted users will
not contribute to unread counts and notifications.

This commit does not affect the unread messages
(if any) present just before muting, but only handles
subsequent messages. Old unreads will be handled in
further commits.

zerver/lib/actions.py

@@ -167,7 +167,7 @@ from zerver.lib.upload import (
     upload_emoji_image,
 )
 from zerver.lib.user_groups import access_user_group_by_id, create_user_group
-from zerver.lib.user_mutes import add_user_mute, get_user_mutes
+from zerver.lib.user_mutes import add_user_mute, get_muting_users, get_user_mutes
 from zerver.lib.user_status import update_user_status
 from zerver.lib.users import (
     check_bot_name_available,
@@ -1848,6 +1848,11 @@ def do_send_messages(
             # Service bots (outgoing webhook bots and embedded bots) don't store UserMessage rows;
             # they will be processed later.
             mentioned_user_ids = send_request.message.mentions_user_ids
+
+            # Extend the set with users who have muted the sender.
+            mark_as_read_for_users = get_muting_users(send_request.message.sender)
+            mark_as_read_for_users.update(mark_as_read)
+
             user_messages = create_user_messages(
                 message=send_request.message,
                 um_eligible_user_ids=send_request.um_eligible_user_ids,
@@ -1855,7 +1860,7 @@ def do_send_messages(
                 stream_push_user_ids=send_request.stream_push_user_ids,
                 stream_email_user_ids=send_request.stream_email_user_ids,
                 mentioned_user_ids=mentioned_user_ids,
-                mark_as_read=mark_as_read,
+                mark_as_read_for_users=mark_as_read_for_users,
             )
 
             for um in user_messages:
@@ -2030,7 +2035,7 @@ def create_user_messages(
     stream_push_user_ids: AbstractSet[int],
     stream_email_user_ids: AbstractSet[int],
     mentioned_user_ids: AbstractSet[int],
-    mark_as_read: Sequence[int] = [],
+    mark_as_read_for_users: Set[int],
 ) -> List[UserMessageLite]:
     ums_to_create = []
     for user_profile_id in um_eligible_user_ids:
@@ -2049,7 +2054,7 @@ def create_user_messages(
     for um in ums_to_create:
         if (
             um.user_profile_id == message.sender.id and message.sent_by_human()
-        ) or um.user_profile_id in mark_as_read:
+        ) or um.user_profile_id in mark_as_read_for_users:
             um.flags |= UserMessage.flags.read
         if wildcard:
             um.flags |= UserMessage.flags.wildcard_mentioned