From 0cffaa7b5daba1fd9565bd9a10b92a420cd9682f Mon Sep 17 00:00:00 2001
From: Aman Agrawal <amanagr@zulip.com>
Date: Fri, 12 Jun 2020 14:51:35 +0530
Subject: [PATCH] ui: Upgrade remove_message to allow removing messages in
 bulk.

We simply pass the visible message ids to remove_and_rerender
which supports bulk delete operation.

This helps us avoid deleting messages in a loop which freezes the
UI for the duration of the loop.
---
 frontend_tests/node_tests/dispatch.js |  6 +++---
 static/js/server_events_dispatch.js   |  7 +------
 static/js/ui.js                       | 12 ++++++++----
 3 files changed, 12 insertions(+), 13 deletions(-)

diff --git a/frontend_tests/node_tests/dispatch.js b/frontend_tests/node_tests/dispatch.js
index d4c194a027..7317a9d90d 100644
--- a/frontend_tests/node_tests/dispatch.js
+++ b/frontend_tests/node_tests/dispatch.js
@@ -799,10 +799,10 @@ with_overrides(function (override) {
     override('stream_list.update_streams_sidebar', noop);
     global.with_stub(function (stub) {
         override('unread_ops.process_read_messages_event', noop);
-        override('ui.remove_message', stub.f);
+        override('ui.remove_messages', stub.f);
         dispatch(event);
-        const args = stub.get_args('message_id');
-        assert_same(args.message_id, 1337);
+        const args = stub.get_args('message_ids');
+        assert_same(args.message_ids, [1337]);
     });
     global.with_stub(function (stub) {
         override('unread_ops.process_read_messages_event', stub.f);
diff --git a/static/js/server_events_dispatch.js b/static/js/server_events_dispatch.js
index cc52c7ed33..d494041b52 100644
--- a/static/js/server_events_dispatch.js
+++ b/static/js/server_events_dispatch.js
@@ -37,12 +37,7 @@ exports.dispatch_normal_event = function dispatch_normal_event(event) {
             stream_list.update_streams_sidebar();
         }
 
-        // TODO: Do this as a bulk process.
-        // We may need to change narrow too,
-        // but that maybe confusing to users.
-        for (const msg_id of msg_ids) {
-            ui.remove_message(msg_id);
-        }
+        ui.remove_messages(msg_ids);
         break;
     }
 
diff --git a/static/js/ui.js b/static/js/ui.js
index 07644c3896..17ce56e3c9 100644
--- a/static/js/ui.js
+++ b/static/js/ui.js
@@ -114,15 +114,19 @@ exports.show_message_failed = function (message_id, failed_msg) {
     });
 };
 
-exports.remove_message = function (message_id) {
+exports.remove_messages = function (message_ids) {
+    const msg_ids_to_rerender = [];
     for (const list of [message_list.all, home_msg_list, message_list.narrowed]) {
         if (list === undefined) {
             continue;
         }
-        const row = list.get_row(message_id);
-        if (row !== undefined) {
-            list.remove_and_rerender([{id: message_id}]);
+        for (const message_id of message_ids) {
+            const row = list.get_row(message_id);
+            if (row !== undefined) {
+                msg_ids_to_rerender.push({id: message_id});
+            }
         }
+        list.remove_and_rerender(msg_ids_to_rerender);
     }
 };