Add support for topic narrows in our embedded narrow widget.

(imported from commit d3ef2db8e0903e445d9ecc2c28d9f249a0042bd9)

static/js/compose.js

@@ -257,7 +257,11 @@ exports.cancel = function () {
         // Never close the compose box in narrow embedded windows, but
         // at least clear the subject and unfade.
         compose_fade.clear_compose();
+        if (page_params.narrow_topic !== undefined) {
+            compose.subject(page_params.narrow_topic);
+        } else {
             compose.subject("");
+        }
         return;
     }
     hide_box();
@@ -906,8 +910,12 @@ $(function () {
     });
 
     if (page_params.narrow !== undefined) {
+        if (page_params.narrow_topic !== undefined) {
+            compose.start("stream", {subject: page_params.narrow_topic});
+        } else {
             compose.start("stream", {});
         }
+    }
 });
 
 return exports;

static/js/zulip.js

@@ -1115,7 +1115,7 @@ function load_old_messages(opts) {
         data.narrow = JSON.stringify(operators);
     }
     if (opts.msg_list === home_msg_list && page_params.narrow_stream !== undefined) {
-        data.narrow = JSON.stringify([["stream", page_params.narrow_stream]]);
+        data.narrow = JSON.stringify(page_params.narrow);
     }
 
     channel.post({

zerver/views/__init__.py

@@ -754,6 +754,7 @@ def home(request):
 
     narrow = []
     narrow_stream = None
+    narrow_topic = request.GET.get("topic")
     if request.GET.get("narrow"):
         try:
             narrow_stream = get_stream(request.GET.get("narrow"), user_profile.realm)
@@ -762,6 +763,8 @@ def home(request):
             narrow = [["stream", narrow_stream.name]]
         except Exception:
             logging.exception("Narrow parsing")
+        if narrow_topic is not None:
+            narrow.append(["topic", narrow_topic])
 
     register_ret = do_events_register(user_profile, request.client,
                                       apply_markdown=True, narrow=narrow)
@@ -868,6 +871,8 @@ def home(request):
         except IndexError:
             initial_pointer = -1
         page_params["narrow_stream"] = narrow_stream.name
+        if narrow_topic is not None:
+            page_params["narrow_topic"] = narrow_topic
         page_params["narrow"] = narrow
         page_params["max_message_id"] = initial_pointer
         page_params["initial_pointer"] = initial_pointer