[FIX] mail: easily mention followers and employees in chatter

Revision on https://github.com/odoo/odoo/commit/cd34f6de727d5b3858420cff3c9d3c5995c4e75c

Resulting of the mail JS refactoring, the list of prefetched suggestions
has been changed as follow:

- before: list of list of mention suggestions `{Array<Object[]>}`
- after: list of mention suggestions `{Object[]}`

The change resulted in wrongly thinking that wrapping the list of
suggestions in a list was pointless, thus simplifying it as a simple
list of mention suggestions.

However, because of this change, it has become much harder to
mention employees and followers of documents from the chatter:
it now always fetches all partner suggestions at all time, whereas
before it was suggesting followers, then employees, and finally all
partners based on the input of the user.

In fact, there was a purpose of using a list of list of prefetched
mention suggestions, which is to group suggestions by "priority":
followers first, then employees, and all partners as a last resort.

This commit re-introduces prefetched mention suggestions as a list
of list of partners, so that it re-becomes easier to mention
followers and partners of a document from the chatter.

Task-ID 1910111

5 files changed, 24 insertions, 19 deletions

diff --git a/addons/mail/static/src/js/composers/basic_composer.js b/addons/mail/static/src/js/composers/basic_composer.js
index a6cdb39e2de..8a533cd4515 100644
--- a/addons/mail/static/src/js/composers/basic_composer.js
+++ b/addons/mail/static/src/js/composers/basic_composer.js
@@ -211,7 +211,8 @@ var BasicComposer = Widget.extend({
      * displayed to the user. If none of them match, then it will fetch for more
      * partner suggestions (@see _mentionFetchPartners).
      *
-     * @param {$.Deferred<Object[]>} prefetchedPartners
+     * @param {$.Deferred<Object[]>} prefetchedPartners list of list of
+     *   prefetched partners.
      */
     mentionSetPrefetchedPartners: function (prefetchedPartners) {
         this._mentionPrefetchedPartners = prefetchedPartners;
@@ -302,21 +303,23 @@ var BasicComposer = Widget.extend({
      */
     _mentionFetchPartners: function (search) {
         var self = this;
-        return $.when(this._mentionPrefetchedPartners).then(function (partners) {
+        return $.when(this._mentionPrefetchedPartners).then(function (prefetchedPartners) {
             // filter prefetched partners with the given search string
             var suggestions = [];
             var limit = self.options.mentionFetchLimit;
             var searchRegexp = new RegExp(_.str.escapeRegExp(mailUtils.unaccent(search)), 'i');
-            if (limit > 0) {
-                var filteredPartners = _.filter(partners, function (partner) {
-                    return partner.email && searchRegexp.test(partner.email) ||
-                           partner.name && searchRegexp.test(mailUtils.unaccent(partner.name));
-                });
-                if (filteredPartners.length) {
-                    suggestions.push(filteredPartners.slice(0, limit));
-                    limit -= filteredPartners.length;
+            _.each(prefetchedPartners, function (partners) {
+                if (limit > 0) {
+                    var filteredPartners = _.filter(partners, function (partner) {
+                        return partner.email && searchRegexp.test(partner.email) ||
+                            partner.name && searchRegexp.test(mailUtils.unaccent(partner.name));
+                    });
+                    if (filteredPartners.length) {
+                        suggestions.push(filteredPartners.slice(0, limit));
+                        limit -= filteredPartners.length;
+                    }
                 }
-            }
+            });
             if (!suggestions.length && !self.options.mentionPartnersRestricted) {
                 // no result found among prefetched partners, fetch other suggestions
                 suggestions = self._mentionFetchThrottled(
diff --git a/addons/mail/static/src/js/models/threads/channel.js b/addons/mail/static/src/js/models/threads/channel.js
index 695275e799e..808e8b7fbca 100644
--- a/addons/mail/static/src/js/models/threads/channel.js
+++ b/addons/mail/static/src/js/models/threads/channel.js
@@ -179,7 +179,8 @@ var Channel = SearchableThread.extend(ThreadTypingMixin, {
     /**
      * Get listeners of a channel
      *
-     * @returns {$.Promise<Object[]>} resolved with list of channel listeners
+     * @returns {$.Promise<Array<Object[]>>} resolved with list of list of
+     *   channel listeners.
      */
     getMentionPartnerSuggestions: function () {
         var self = this;
@@ -193,7 +194,7 @@ var Channel = SearchableThread.extend(ThreadTypingMixin, {
             })
             .then(function (members) {
                 self._members = members;
-                return members;
+                return [members];
             });
         }
         return this._membersDef;
diff --git a/addons/mail/static/src/js/models/threads/livechat.js b/addons/mail/static/src/js/models/threads/livechat.js
index b7235e7bc0e..f4cb58ebad3 100644
--- a/addons/mail/static/src/js/models/threads/livechat.js
+++ b/addons/mail/static/src/js/models/threads/livechat.js
@@ -37,7 +37,8 @@ var Livechat = TwoUserChannel.extend({
      * display of a user that is typing.
      *
      * @override
-     * @returns {$.Promise<Object[]>} resolved with list of livechat members
+     * @returns {$.Promise<Array<Object[]>>} resolved with list of list of
+     *   livechat members.
      */
     getMentionPartnerSuggestions: function () {
         var self = this;
@@ -49,7 +50,7 @@ var Livechat = TwoUserChannel.extend({
                     name: self._WEBSITE_USER_NAME,
                 });
             }
-            return self._members;
+            return [self._members];
         });
     },
     /**
diff --git a/addons/mail/static/src/js/models/threads/thread.js b/addons/mail/static/src/js/models/threads/thread.js
index c9dda28dd93..b15ceb8563c 100644
--- a/addons/mail/static/src/js/models/threads/thread.js
+++ b/addons/mail/static/src/js/models/threads/thread.js
@@ -111,7 +111,7 @@ var Thread = AbstractThread.extend(ServicesMixin, {
      * By default, a thread has not listener.
      *
      * @abstract
-     * @returns {$.Promise<Object[]>}
+     * @returns {$.Promise<Array<Object[]>>}
      */
     getMentionPartnerSuggestions: function () {
         return $.when([]);
diff --git a/addons/mail/static/src/js/services/mail_manager.js b/addons/mail/static/src/js/services/mail_manager.js
index 734f12f0cf3..c21089b7095 100644
--- a/addons/mail/static/src/js/services/mail_manager.js
+++ b/addons/mail/static/src/js/services/mail_manager.js
@@ -199,7 +199,7 @@ var MailManager =  AbstractService.extend({
      * Get partners as mentions from a chatter
      * Typically all employees as partner suggestions.
      *
-     * @returns {Array<Object[]>}
+     * @returns {Array<Array<Object[]>>}
      */
     getMentionPartnerSuggestions: function () {
         return this._mentionPartnerSuggestions;
@@ -1195,8 +1195,8 @@ var MailManager =  AbstractService.extend({
      *
      * @private
      * @param {Object} result data from server on mail/init_messaging rpc
-     * @param {Object[]} result.mention_partner_suggestions list of suggestions
-     *   with all the employees
+     * @param {Array<Object[]>} result.mention_partner_suggestions list of
+     *   suggestions.
      * @param {integer} result.menu_id the menu ID of discuss app
      */
     _updateInternalStateFromServer: function (result) {