[FIX] mail: chatter: keep mentions

Message's body is kept when switching from 'New message' to 'Log a note' since
rev. f35b48aa. However, mentionned partners or channels were lost. This rev.
makes sure to preserve both message's body and mentions when switching between
composers.

addons/mail/static/src/js/chatter.js

@@ -451,7 +451,6 @@ var ChatterComposer = composer.BasicComposer.extend({
             record_name: false,
             is_log: false,
             internal_subtypes: [],
-            default_body: '',
         });
         if (this.options.is_log) {
             this.options.send_text = _('Log');
@@ -468,13 +467,6 @@ var ChatterComposer = composer.BasicComposer.extend({
         return $.when(this._super.apply(this, arguments), this.message_get_suggested_recipients());
     },
 
-    start: function () {
-        var self = this;
-        return this._super().then(function () {
-            self.$input.val(self.options.default_body);
-        });
-    },
-
     should_send: function () {
         return false;
     },
@@ -920,6 +912,7 @@ var Chatter = form_common.AbstractField.extend({
             is_log: options && options.is_log,
             record_name: this.record_name,
             default_body: old_composer && old_composer.$input.val(),
+            default_mention_selections: old_composer && old_composer.mention_get_listener_selections(),
         });
         this.composer.on('input_focused', this, function () {
             this.composer.mention_set_prefetched_partners(this.mention_suggestions || []);

addons/mail/static/src/js/composer.js

@@ -27,6 +27,9 @@ var accented_letters_mapping = {
     ' ': '[()\\[\\]]',
 };
 
+var MENTION_PARTNER_DELIMITER = '@';
+var MENTION_CHANNEL_DELIMITER = '#';
+
 // The MentionManager allows the Composer to register listeners. For each
 // listener, it detects if the user is currently typing a mention (starting by a
 // given delimiter). If so, if fetches mention suggestions and renders them. On
@@ -106,7 +109,7 @@ var MentionManager = Widget.extend({
      * @param {string} [redirect_classname] the classname of the <a> wrapping the mention
      */
     register: function (listener) {
-        this.listeners.push(_.extend(listener, {
+        this.listeners.push(_.defaults(listener, {
             selection: [],
         }));
     },
@@ -123,6 +126,14 @@ var MentionManager = Widget.extend({
         return listener ? listener.selection : [];
     },
 
+    get_listener_selections: function () {
+        var selections = {};
+        _.each(this.listeners, function (listener) {
+            selections[listener.delimiter] = listener.selection;
+        });
+        return selections;
+    },
+
     proposition_navigation: function (keycode) {
         var $active = this.$('.o_mention_proposition.active');
         if (keycode === $.ui.keyCode.ENTER) { // selecting proposition
@@ -333,6 +344,8 @@ var BasicComposer = Widget.extend({
             mention_fetch_limit: 8,
             mention_partners_restricted: false, // set to true to only suggest prefetched partners
             send_text: _('Send'),
+            default_body: '',
+            default_mention_selections: {},
         });
         this.context = this.options.context;
 
@@ -344,16 +357,18 @@ var BasicComposer = Widget.extend({
         // Mention
         this.mention_manager = new MentionManager(this);
         this.mention_manager.register({
-            delimiter: '@',
+            delimiter: MENTION_PARTNER_DELIMITER,
             fetch_callback: this.mention_fetch_partners.bind(this),
             model: 'res.partner',
             redirect_classname: 'o_mail_redirect',
+            selection: this.options.default_mention_selections[MENTION_PARTNER_DELIMITER],
         });
         this.mention_manager.register({
-            delimiter: '#',
+            delimiter: MENTION_CHANNEL_DELIMITER,
             fetch_callback: this.mention_fetch_channels.bind(this),
             model: 'mail.channel',
             redirect_classname: 'o_channel_redirect',
+            selection: this.options.default_mention_selections[MENTION_CHANNEL_DELIMITER],
         });
 
         // Emojis
@@ -372,6 +387,7 @@ var BasicComposer = Widget.extend({
         this.$input.focus(function () {
             self.trigger('input_focused');
         });
+        this.$input.val(this.options.default_body);
         dom_utils.autoresize(this.$input, {parent: this, min_height: this.options.input_min_height});
 
         // Attachments
@@ -635,6 +651,9 @@ var BasicComposer = Widget.extend({
     mention_set_prefetched_partners: function (prefetched_partners) {
         this.mention_prefetched_partners = prefetched_partners;
     },
+    mention_get_listener_selections: function () {
+        return this.mention_manager.get_listener_selections();
+    },
 
     // Others
     is_empty: function () {