[FIX] web: ActionManager: honor action's groupBy

Before this rev., the group_by specified in the action context was
completely overridden by the group_by specified in the search view,
even if it was []. In other words, it was completely ignored.

Moreover, it was only took into account (before being overridden)
at the first load of a view, not at reload.

addons/web/static/src/js/chrome/action_manager_act_window.js

@@ -302,10 +302,6 @@ ActionManager.include({
      * @returns {Object}
      */
     _generateActionEnv: function (action, options) {
-        var actionGroupBy = action.context.group_by || [];
-        if (typeof actionGroupBy === 'string') {
-            actionGroupBy = [actionGroupBy];
-        }
         var resID = options.resID || action.res_id;
         return {
             modelName: action.res_model,
@@ -313,7 +309,7 @@ ActionManager.include({
             currentId: resID || undefined,
             domain: [],
             context: action.context || {},
-            groupBy: actionGroupBy,
+            groupBy: [],
         };
     },
     /**
@@ -444,10 +440,11 @@ ActionManager.include({
             throw new Error(_.str.sprintf(_t("Failed to evaluate search criterions")+": \n%s",
                             JSON.stringify(results.error)));
         }
+        var groupBy = results.group_by.length ? results.group_by : (action.context.group_by || []);
         return {
             context: results.context,
             domain: results.domain,
-            groupBy: results.group_by,
+            groupBy: (typeof groupBy === 'string') ? [groupBy] : groupBy,
         };
     },
     /**

addons/web/static/tests/chrome/action_manager_tests.js

@@ -18,11 +18,11 @@ QUnit.module('ActionManager', {
                     bar: {string: "Bar", type: "many2one", relation: 'partner'},
                 },
                 records: [
-                    {id: 1, display_name: "First record", foo: "yop"},
-                    {id: 2, display_name: "Second record", foo: "blip"},
-                    {id: 3, display_name: "Third record", foo: "gnap"},
-                    {id: 4, display_name: "Fourth record", foo: "plop"},
-                    {id: 5, display_name: "Fifth record", foo: "zoup"},
+                    {id: 1, display_name: "First record", foo: "yop", bar: 2},
+                    {id: 2, display_name: "Second record", foo: "blip", bar: 1},
+                    {id: 3, display_name: "Third record", foo: "gnap", bar: 1},
+                    {id: 4, display_name: "Fourth record", foo: "plop", bar: 2},
+                    {id: 5, display_name: "Fifth record", foo: "zoup", bar: 2},
                 ],
             },
             pony: {
@@ -2223,6 +2223,47 @@ QUnit.module('ActionManager', {
         actionManager.destroy();
     });
 
+    QUnit.test('honor group_by specified in actions context', function (assert) {
+        assert.expect(5);
+
+        _.findWhere(this.actions, {id: 3}).context = "{'group_by': 'bar'}";
+        this.archs['partner,false,search'] = '<search>'+
+            '<group>'+
+                '<filter name="foo" string="foo" context="{\'group_by\': \'foo\'}"/>' +
+            '</group>'+
+        '</search>';
+
+        var actionManager = createActionManager({
+            actions: this.actions,
+            archs: this.archs,
+            data: this.data,
+        });
+        actionManager.doAction(3);
+
+        assert.strictEqual(actionManager.$('.o_list_view_grouped').length, 1,
+            "should be grouped");
+        assert.strictEqual(actionManager.$('.o_group_header').length, 2,
+            "should be grouped by 'bar' (two groups) at first load");
+
+        // groupby 'bar' using the searchview
+        $('.o_control_panel .o_searchview_more').click(); // open search view sub menus
+        $('.o_control_panel .o_cp_right button:contains(Group By)').click(); // open groupby dropdown
+        $('.o_control_panel .o_group_by_menu a:first').click(); // click on 'Foo'
+
+        assert.strictEqual(actionManager.$('.o_group_header').length, 5,
+            "should be grouped by 'foo' (five groups)");
+
+        // remove the groupby in the searchview
+        $('.o_control_panel .o_searchview .o_facet_remove').click();
+
+        assert.strictEqual(actionManager.$('.o_list_view_grouped').length, 1,
+            "should still be grouped");
+        assert.strictEqual(actionManager.$('.o_group_header').length, 2,
+            "should be grouped by 'bar' (two groups) at reload");
+
+        actionManager.destroy();
+    });
+
     QUnit.module('Actions in target="new"');
 
     QUnit.test('can execute act_window actions in target="new"', function (assert) {