From f706efe12e7b1fc7b0dc6ea582463de52fb98aaa Mon Sep 17 00:00:00 2001
From: Steve Howell <showell@zulipchat.com>
Date: Thu, 10 Aug 2017 18:29:35 -0400
Subject: [PATCH] Add topic_list.active_stream_id().

---
 frontend_tests/node_tests/topic_list.js | 4 ++++
 static/js/topic_list.js                 | 8 ++++++++
 2 files changed, 12 insertions(+)

diff --git a/frontend_tests/node_tests/topic_list.js b/frontend_tests/node_tests/topic_list.js
index f259356b3a..855b53ff48 100644
--- a/frontend_tests/node_tests/topic_list.js
+++ b/frontend_tests/node_tests/topic_list.js
@@ -74,6 +74,8 @@ zrequire('topic_list');
         attached_to_parent = true;
     };
 
+    assert.equal(topic_list.active_stream_id(), undefined);
+
     var widget = topic_list.build_widget(parent_elem, stream_id, active_topic, max_topics);
 
     assert(widget.is_for_stream(stream_id));
@@ -83,4 +85,6 @@ zrequire('topic_list');
     assert(rendered);
     assert(item_appended);
     assert(attached_to_parent);
+
+    assert.equal(topic_list.active_stream_id(), stream_id);
 }());
diff --git a/static/js/topic_list.js b/static/js/topic_list.js
index 0b70e790d0..bdf0f163f9 100644
--- a/static/js/topic_list.js
+++ b/static/js/topic_list.js
@@ -155,6 +155,14 @@ exports.build_widget = function (parent_elem, my_stream_id, active_topic, max_to
     return self;
 };
 
+exports.active_stream_id = function () {
+    if (!active_widget) {
+        return;
+    }
+
+    return active_widget.get_stream_id();
+};
+
 exports.rebuild = function (stream_li, stream_id) {
     var max_topics = 5;