2 files changed, 17 insertions, 1 deletions
diff --git a/addons/web/static/src/js/views/basic/basic_model.js b/addons/web/static/src/js/views/basic/basic_model.js
index 979f8ae3fec..0b2d35cb89f 100644
--- a/addons/web/static/src/js/views/basic/basic_model.js
+++ b/addons/web/static/src/js/views/basic/basic_model.js
@@ -3166,6 +3166,9 @@ var BasicModel = AbstractModel.extend({
      * @param {Object} [options]
      * @param {string[]} [options.fieldNames] the fields to fetch for a record
      * @param {boolean} [options.onlyGroups=false]
+     * @param {boolean} [options.keepEmptyGroups=false] if set, the groups not
+     *   present in the read_group anymore (empty groups) will stay in the
+     *   datapoint (used to mimic the kanban renderer behaviour for example)
      * @returns {Deferred}
      */
     _load: function (dataPoint, options) {
@@ -3796,6 +3799,16 @@ var BasicModel = AbstractModel.extend({
                         defs.push(self._load(newGroup, options));
                     }
                 });
+                if (options && options.keepEmptyGroups) {
+                    // Find the groups that were available in a previous
+                    // readGroup but are not there anymore.
+                    // Note that these groups are put after existing groups so
+                    // the order is not conserved. A sort *might* be useful.
+                    var emptyGroupsIDs = _.difference(_.pluck(previousGroups, 'id'), list.data);
+                    _.each(emptyGroupsIDs, function (groupID) {
+                        list.data.push(groupID);
+                    });
+                }
                 return $.when.apply($, defs).then(function () {
                     // generate the res_ids of the main list, being the concatenation
                     // of the fetched res_ids in each group
diff --git a/addons/web/static/src/js/views/kanban/kanban_model.js b/addons/web/static/src/js/views/kanban/kanban_model.js
index 0b0ec09ddf4..427d10f6032 100644
--- a/addons/web/static/src/js/views/kanban/kanban_model.js
+++ b/addons/web/static/src/js/views/kanban/kanban_model.js
@@ -369,7 +369,10 @@ var KanbanModel = BasicModel.extend({
         while (element) {
             if (element.progressBar) {
                 return def.then(function (data) {
-                    return self._load(element, {onlyGroups: true}).then(function () {
+                    return self._load(element, {
+                        keepEmptyGroups: true,
+                        onlyGroups: true,
+                    }).then(function () {
                         return data;
                     });
                 });