refactor: Extract huddle_data.js.

This makes it so that search_suggestion.js
does not depend on activity.js.

That dependency hasn't really been "elegant"
for quite some time, but it will become particularly
unnecessary when we go to remove the "Group PMs"
section from the right sidebar.

This commit introduces a temporary wart
where we have these two functions with the
same name in a sort of unnecessarily
complicated code stack:

    activity.process_loaded_messages
    huddle_data.process_loaded_messages

But we will eliminate the former function
very soon, and our message-related codepaths
will just call the `huddle_data` version
directly.

TESTING NOTES:

Now that `huddle_data` is a tiny leaf
module, it's super easy to just use the
real implementation of what was formerly
called `activity.get_huddles()` (and is
now in `huddle_data`).

When I first wrote this commit, introducing
the real implementation of `get_huddles` exposed
some bugs that I fixed in the immediately
prior commits to this.

When the tests were originally written,
I believe `activity.js` had some annoying
`jQuery` dependencies that made it hard
to unit test against.  We've slimmed it over
time to be mostly just a "controller" module.
But even in its current state it would have
been a bit of a bloated dependency.

The other friction for using the actual
version of `get_huddles` was setting up
the message data, but that's pretty minor.

frontend_tests/node_tests/activity.js

@@ -2,6 +2,8 @@ set_global('$', global.make_zjquery());
 
 let filter_key_handlers;
 
+const huddle_data = zrequire('huddle_data');
+
 const _page_params = {
     realm_users: [],
     user_id: 999,
@@ -212,7 +214,7 @@ run_test('process_loaded_messages', () => {
 
     const user_ids_string1 = people.emails_strings_to_user_ids_string(huddle1);
     const user_ids_string2 = people.emails_strings_to_user_ids_string(huddle2);
-    assert.deepEqual(activity.get_huddles(), [user_ids_string2, user_ids_string1]);
+    assert.deepEqual(huddle_data.get_huddles(), [user_ids_string2, user_ids_string1]);
 });
 
 run_test('full_huddle_name', () => {
@@ -742,18 +744,18 @@ run_test('update_huddles_and_redraw', () => {
     li.set_find_results('.count', count);
     count.set_parent(li);
 
-    const real_get_huddles = activity.get_huddles;
-    activity.get_huddles = () => ['1,2'];
+    const real_get_huddles = huddle_data.get_huddles;
+    huddle_data.get_huddles = () => ['1,2'];
     activity.update_huddles = real_update_huddles;
     activity.redraw();
     assert.equal($('#group-pm-list').hasClass('show'), false);
     page_params.realm_presence_disabled = false;
     activity.redraw();
     assert.equal($('#group-pm-list').hasClass('show'), true);
-    activity.get_huddles = () => [];
+    huddle_data.get_huddles = () => [];
     activity.redraw();
     assert.equal($('#group-pm-list').hasClass('show'), false);
-    activity.get_huddles = real_get_huddles;
+    huddle_data.get_huddles = real_get_huddles;
     activity.update_huddles = function () {};
 });
 

frontend_tests/node_tests/search_suggestion.js

@@ -10,6 +10,8 @@ const settings_config = zrequire('settings_config');
 page_params.realm_email_address_visibility =
     settings_config.email_address_visibility_values.admins_only.code;
 
+const huddle_data = zrequire('huddle_data');
+
 zrequire('typeahead_helper');
 set_global('Handlebars', global.make_handlebars());
 zrequire('Filter', 'js/filter');
@@ -281,12 +283,6 @@ run_test('group_suggestions', () => {
         return;
     };
 
-    set_global('activity', {
-        get_huddles: function () {
-            return [];
-        },
-    });
-
     // Entering a comma in a pm-with query should immediately generate
     // suggestions for the next person.
     let query = 'pm-with:bob@zulip.com,';
@@ -388,11 +384,22 @@ run_test('group_suggestions', () => {
     ];
     assert.deepEqual(suggestions.strings, expected);
 
-    set_global('activity', {
-        get_huddles: function () {
-            return ['42,101', '42,101,103'];
-        },
-    });
+    function message(user_ids, timestamp) {
+        return {
+            type: 'private',
+            display_recipient: user_ids.map((id) => {
+                return {
+                    id: id,
+                };
+            }),
+            timestamp: timestamp,
+        };
+    }
+
+    huddle_data.process_loaded_messages([
+        message([bob.user_id, ted.user_id], 99),
+        message([bob.user_id, ted.user_id, jeff.user_id], 98),
+    ]);
 
     // Simulate a past huddle which should now prioritize ted over alice
     query = 'pm-with:bob@zulip.com,';

frontend_tests/node_tests/search_suggestion_legacy.js

@@ -9,6 +9,8 @@ const settings_config = zrequire('settings_config');
 page_params.realm_email_address_visibility =
     settings_config.email_address_visibility_values.admins_only.code;
 
+const huddle_data = zrequire('huddle_data');
+
 zrequire('typeahead_helper');
 set_global('Handlebars', global.make_handlebars());
 zrequire('Filter', 'js/filter');
@@ -278,12 +280,6 @@ run_test('group_suggestions', () => {
         return;
     };
 
-    set_global('activity', {
-        get_huddles: function () {
-            return [];
-        },
-    });
-
     // Entering a comma in a pm-with query should immediately generate
     // suggestions for the next person.
     let query = 'pm-with:bob@zulip.com,';
@@ -387,11 +383,22 @@ run_test('group_suggestions', () => {
     ];
     assert.deepEqual(suggestions.strings, expected);
 
-    set_global('activity', {
-        get_huddles: function () {
-            return ['42,101', '42,101,103'];
-        },
-    });
+    function message(user_ids, timestamp) {
+        return {
+            type: 'private',
+            display_recipient: user_ids.map((id) => {
+                return {
+                    id: id,
+                };
+            }),
+            timestamp: timestamp,
+        };
+    }
+
+    huddle_data.process_loaded_messages([
+        message([bob.user_id, ted.user_id], 99),
+        message([bob.user_id, ted.user_id, jeff.user_id], 98),
+    ]);
 
     // Simulate a past huddle which should now prioritize ted over alice
     query = 'pm-with:bob@zulip.com,';

static/js/activity.js

@@ -1,4 +1,5 @@
 const render_group_pms = require('../templates/group_pms.hbs');
+const huddle_data = require("./huddle_data");
 
 /*
     Helpers for detecting user activity and managing user idle states
@@ -26,8 +27,6 @@ exports.client_is_active = document.hasFocus && document.hasFocus();
 // server-initiated reload as user activity.
 exports.new_user_input = true;
 
-const huddle_timestamps = new Map();
-
 function update_pm_count_in_dom(count_span, value_span, count) {
     const li = count_span.parents('li');
 
@@ -96,20 +95,7 @@ exports.update_dom_with_unread_counts = function (counts) {
 };
 
 exports.process_loaded_messages = function (messages) {
-    let need_resize = false;
-
-    for (const message of messages) {
-        const huddle_string = people.huddle_string(message);
-
-        if (huddle_string) {
-            const old_timestamp = huddle_timestamps.get(huddle_string);
-
-            if (!old_timestamp || old_timestamp < message.timestamp) {
-                huddle_timestamps.set(huddle_string, message.timestamp);
-                need_resize = true;
-            }
-        }
-    }
+    const need_resize = huddle_data.process_loaded_messages(messages);
 
     exports.update_huddles();
 
@@ -118,14 +104,6 @@ exports.process_loaded_messages = function (messages) {
     }
 };
 
-exports.get_huddles = function () {
-    let huddles = Array.from(huddle_timestamps.keys());
-    huddles = _.sortBy(huddles, function (huddle) {
-        return huddle_timestamps.get(huddle);
-    });
-    return huddles.reverse();
-};
-
 function huddle_split(huddle) {
     return huddle.split(',').map(s => parseInt(s, 10));
 }
@@ -236,7 +214,7 @@ exports.update_huddles = function () {
         return;
     }
 
-    const huddles = exports.get_huddles().slice(0, 10);
+    const huddles = huddle_data.get_huddles().slice(0, 10);
 
     if (huddles.length === 0) {
         hide_huddles();

static/js/huddle_data.js

@@ -0,0 +1,30 @@
+const huddle_timestamps = new Map();
+
+exports.process_loaded_messages = function (messages) {
+    let need_resize = false;
+
+    for (const message of messages) {
+        const huddle_string = people.huddle_string(message);
+
+        if (huddle_string) {
+            const old_timestamp = huddle_timestamps.get(huddle_string);
+
+            if (!old_timestamp || old_timestamp < message.timestamp) {
+                huddle_timestamps.set(huddle_string, message.timestamp);
+                need_resize = true;
+            }
+        }
+    }
+
+    return need_resize;
+};
+
+exports.get_huddles = function () {
+    let huddles = Array.from(huddle_timestamps.keys());
+    huddles = _.sortBy(huddles, function (huddle) {
+        return huddle_timestamps.get(huddle);
+    });
+    return huddles.reverse();
+};
+
+window.huddle_data = exports;

static/js/search_suggestion.js

@@ -1,4 +1,5 @@
 const settings_data = require("./settings_data");
+const huddle_data = require("./huddle_data");
 
 exports.max_num_of_search_results = 12;
 
@@ -53,7 +54,7 @@ function compare_by_huddle(huddle) {
     });
 
     // Construct dict for all huddles, so we can lookup each's recency
-    const huddles = activity.get_huddles();
+    const huddles = huddle_data.get_huddles();
     const huddle_dict = new Map();
     for (const [i, huddle] of huddles.entries()) {
         huddle_dict.set(huddle, i + 1);