streams: Allow creating stream pills to submit Add subscriber form.

We update the pills typeahead logic to also include
stream results and pass the "stream" key in `opts`
to enable this option for the Add subscriber form.

This commit implements the feature of adding all the
subscribers of another stream in the "Add subscribers"
UI, with the help of a new "stream_pill.js` file.

We temporarily add `user_pill.js` to the EXEMPT_FILES
list as typeahead will be set up in `stream_edit.js`
file which does not have any dedicated tests file.

Work towards #15186.

.eslintrc.json

@@ -249,6 +249,7 @@
                 "stream_topic_history": false,
                 "stream_list": false,
                 "stream_muting": false,
+                "stream_pill": false,
                 "stream_popover": false,
                 "stream_sort": false,
                 "stream_ui_updates": false,

static/js/bundles/app.js

@@ -32,6 +32,7 @@ import "../localstorage.js";
 import "../drafts.js";
 import "../input_pill.js";
 import "../user_pill.js";
+import "../stream_pill.js";
 import "../compose_pm_pill.js";
 import "../channel.js";
 import "../setup.js";

static/js/global.d.ts

@@ -145,6 +145,7 @@ declare let stream_edit: any;
 declare let stream_events: any;
 declare let stream_list: any;
 declare let stream_muting: any;
+declare let stream_pill: any;
 declare let stream_popover: any;
 declare let stream_sort: any;
 declare let stream_ui_updates: any;

static/js/pill_typeahead.js

@@ -7,18 +7,35 @@ exports.set_up = function (input, pills, opts) {
     if (!opts.source) {
         source = () => user_pill.typeahead_source(pills);
     }
+    const include_streams = (query) => opts.stream && query.trim().startsWith("#");
 
     input.typeahead({
         items: 5,
         fixed: true,
         dropup: true,
-        source,
+        source() {
+            if (include_streams(this.query)) {
+                return stream_pill.typeahead_source(pills);
+            }
+
+            return source();
+        },
         highlighter(item) {
+            if (include_streams(this.query)) {
+                return typeahead_helper.render_stream(item);
+            }
+
             return typeahead_helper.render_person(item);
         },
         matcher(item) {
             let query = this.query.toLowerCase();
             query = query.replace(/\u00A0/g, String.fromCharCode(32));
+
+            if (include_streams(query)) {
+                query = query.trim().substring(1);
+                return item.name.toLowerCase().indexOf(query) !== -1;
+            }
+
             if (!settings_data.show_email()) {
                 return item.full_name.toLowerCase().includes(query);
             }
@@ -28,10 +45,19 @@ exports.set_up = function (input, pills, opts) {
             );
         },
         sorter(matches) {
+            if (include_streams(this.query)) {
+                return typeahead_helper.sort_streams(matches, this.query.trim().substring(1));
+            }
+
             return typeahead_helper.sort_recipientbox_typeahead(this.query, matches, "");
         },
-        updater(user) {
-            user_pill.append_user(user, pills);
+        updater(item) {
+            if (include_streams(this.query)) {
+                stream_pill.append_stream(item, pills);
+            } else {
+                user_pill.append_user(item, pills);
+            }
+
             input.trigger("focus");
             if (opts.update_func) {
                 opts.update_func();

static/js/stream_edit.js

@@ -203,16 +203,25 @@ function submit_add_subscriber_form(e) {
         return;
     }
 
-    const user_ids = user_pill.get_user_ids(exports.pill_widget);
     const stream_subscription_info_elem = $(".stream_subscription_info").expectOne();
+    let user_ids = user_pill.get_user_ids(exports.pill_widget);
+    user_ids = user_ids.concat(stream_pill.get_user_ids(exports.pill_widget));
+    user_ids = new Set(user_ids);
 
-    if (user_ids.length === 0) {
+    if (user_ids.has(page_params.user_id) && sub.subscribed) {
+        // We don't want to send a request to subscribe ourselves
+        // if we are already subscribed to this stream. This
+        // case occurs when creating user pills from a stream.
+        user_ids.delete(page_params.user_id);
+    }
+    if (user_ids.size === 0) {
         stream_subscription_info_elem
             .text(i18n.t("No user to subscribe."))
             .addClass("text-error")
             .removeClass("text-success");
         return;
     }
+    user_ids = Array.from(user_ids);
 
     function invite_success(data) {
         exports.pill_widget.clear();
@@ -337,7 +346,7 @@ function show_subscription_settings(sub) {
         simplebar_container: $(".subscriber_list_container"),
     });
 
-    const opts = {source: get_users_for_subscriber_typeahead};
+    const opts = {source: get_users_for_subscriber_typeahead, stream: true};
     pill_typeahead.set_up(sub_settings.find(".input"), exports.pill_widget, opts);
 }
 

static/js/stream_pill.js

@@ -0,0 +1,52 @@
+"use strict";
+
+function get_user_ids_from_subs(items) {
+    let user_ids = [];
+    const stream_ids = items.map((item) => item.stream_id);
+    for (const stream_id of stream_ids) {
+        const sub = stream_data.get_sub_by_id(stream_id);
+        if (!sub) {
+            continue;
+        }
+        user_ids = user_ids.concat(sub.subscribers.map());
+    }
+    return user_ids;
+}
+
+exports.get_user_ids = function (pill_widget) {
+    const items = pill_widget.items();
+    let user_ids = get_user_ids_from_subs(items);
+    user_ids = Array.from(new Set(user_ids));
+
+    user_ids = user_ids.filter(Boolean);
+    return user_ids;
+};
+
+exports.append_stream = function (stream, pill_widget) {
+    pill_widget.appendValidatedData({
+        display_value: "#" + stream.name + ": " + stream.subscriber_count + " users",
+        stream_id: stream.stream_id,
+    });
+    pill_widget.clear_text();
+};
+
+exports.get_stream_ids = function (pill_widget) {
+    const items = pill_widget.items();
+    let stream_ids = items.map((item) => item.stream_id);
+    stream_ids = stream_ids.filter(Boolean);
+
+    return stream_ids;
+};
+
+exports.filter_taken_streams = function (items, pill_widget) {
+    const taken_stream_ids = exports.get_stream_ids(pill_widget);
+    items = items.filter((item) => !taken_stream_ids.includes(item.stream_id));
+    return items;
+};
+
+exports.typeahead_source = function (pill_widget) {
+    const potential_streams = stream_data.get_unsorted_subs();
+    return exports.filter_taken_streams(potential_streams, pill_widget);
+};
+
+window.stream_pill = exports;

static/templates/subscription_members.hbs

@@ -12,7 +12,7 @@
                 <div class="add_subscribers_container">
                     <div class="pill-container person_picker">
                         <div class="input" contenteditable="true"
-                          data-placeholder="{{t 'Add subscribers' }}"></div>
+                          data-placeholder="{{t 'Add subscribers. Use #streamname to subscribe a whole stream' }}"></div>
                     </div>
                     <div class="add_subscriber_btn_wrapper inline-block">
                         <button type="submit" name="add_subscriber" class="button add-subscriber-button small rounded" tabindex="0">

tools/test-js-with-node

@@ -136,6 +136,7 @@ EXEMPT_FILES = {
     'static/js/stream_edit.js',
     'static/js/stream_list.js',
     'static/js/stream_muting.js',
+    'static/js/stream_pill.js',
     'static/js/stream_popover.js',
     'static/js/stream_ui_updates.js',
     'static/js/submessage.js',
@@ -157,6 +158,7 @@ EXEMPT_FILES = {
     'static/js/unread_ops.js',
     'static/js/unread_ui.js',
     'static/js/upload_widget.js',
+    'static/js/user_pill.js',
     'static/js/user_status_ui.js',
     'static/js/zcommand.js',
     'static/js/zform.js',