From bb51fe075a81d8d8e3bf1c4b03d5c5885ed52048 Mon Sep 17 00:00:00 2001
From: YashRE42 <33805964+YashRE42@users.noreply.github.com>
Date: Fri, 19 Mar 2021 17:11:04 +0000
Subject: [PATCH] message_flags: Verify early return from send_read on_sucess.

---
 frontend_tests/node_tests/message_flags.js | 28 ++++++++++++++++++++++
 1 file changed, 28 insertions(+)

diff --git a/frontend_tests/node_tests/message_flags.js b/frontend_tests/node_tests/message_flags.js
index 4d792b92e2..df7b075f5d 100644
--- a/frontend_tests/node_tests/message_flags.js
+++ b/frontend_tests/node_tests/message_flags.js
@@ -167,6 +167,34 @@ run_test("read", (override) => {
     });
 });
 
+run_test("read_empty_data", (override) => {
+    // Way to capture posted info in every request
+    let channel_post_opts;
+    override(channel, "post", (opts) => {
+        channel_post_opts = opts;
+    });
+
+    // For testing purpose limit the batch size value to 5 instead of 1000
+    function send_read(messages) {
+        with_field(message_flags, "_unread_batch_size", 5, () => {
+            message_flags.send_read(messages);
+        });
+    }
+
+    // send read to obtain success callback
+    send_read({locally_echoed: false, id: 1});
+
+    // verify early return on empty data
+    const success_callback = channel_post_opts.success;
+    channel_post_opts = {};
+    let empty_data;
+    success_callback(empty_data);
+    assert.deepEqual(channel_post_opts, {});
+    empty_data = {messages: undefined};
+    success_callback(empty_data);
+    assert.deepEqual(channel_post_opts, {});
+});
+
 run_test("collapse_and_uncollapse", (override) => {
     // Way to capture posted info in every request
     let channel_post_opts;