[FIX] web: fix issues when deleting records

This commit solves two issues with deletion:
- deleting the last record in a form view now triggers a history_back
  action, which means that the view will be changed back to the main
  view (a list view for example), instead of staying in form view
- deleting a record did reload the view twice in some cases.

addons/web/static/src/js/views/basic/basic_model.js

@@ -183,17 +183,14 @@ var BasicModel = AbstractModel.extend({
      * parent.
      *
      * @todo we should remove the deleted records from the localData
-     * @todo is it really necessary to reload the data? it seems artificial, and
-     *   the caller should be able to do that himself
      * @todo why can't we infer modelName?
      *
      * @param {string[]} recordIds list of local resources ids. They should all
      *   be of type 'record', and of the same model
      * @param {string} modelName
-     * @param {string} parentID
      * @returns {Deferred}
      */
-    deleteRecords: function (recordIds, modelName, parentID) {
+    deleteRecords: function (recordIds, modelName) {
         var self = this;
         var records = _.map(recordIds, function (id) { return self.localData[id]; });
         return this._rpc({
@@ -208,9 +205,6 @@ var BasicModel = AbstractModel.extend({
                     record.res_id = record.res_ids[record.offset];
                     record.count--;
                 });
-                if (parentID) {
-                    return self.reload(parentID);
-                }
             });
     },
     /**

addons/web/static/src/js/views/form/form_controller.js

@@ -337,6 +337,19 @@ var FormController = BasicController.extend({
         warnings.push('</ul>');
         this.do_warn(_t("The following fields are invalid:"), warnings.join(''));
     },
+    /**
+     * Hook method, called when record(s) has been deleted.
+     *
+     * @override
+     */
+    _onDeletedRecords: function () {
+        var state = this.model.get(this.handle, {raw: true});
+        if (!state.res_ids.length) {
+            this.do_action('history_back');
+        } else {
+            this._super.apply(this, arguments);
+        }
+    },
     /**
      * We just add the current ID to the state pushed. This allows the web
      * client to add it in the url, for example.

addons/web/static/tests/views/form_tests.js

@@ -1852,6 +1852,42 @@ QUnit.module('Views', {
         form.destroy();
     });
 
+    QUnit.test('deleting the last record', function (assert) {
+        assert.expect(6);
+
+        var form = createView({
+            View: FormView,
+            model: 'partner',
+            data: this.data,
+            arch: '<form string="Partners"><field name="foo"></field></form>',
+            viewOptions: {
+                ids: [1],
+                index: 0,
+                sidebar: true,
+            },
+            res_id: 1,
+            mockRPC: function (route, args) {
+                assert.step(args.method);
+                return this._super.apply(this, arguments);
+            }
+        });
+
+        // open sidebar, click on delete and confirm
+        form.sidebar.$('button.o_dropdown_toggler_btn').click();
+        form.sidebar.$('a:contains(Delete)').click();
+
+        testUtils.intercept(form, 'do_action', function (event) {
+            assert.strictEqual(event.data.action, 'history_back',
+                "should trigger an history back action");
+        });
+        assert.strictEqual($('.modal').length, 1, 'a confirm modal should be displayed');
+        $('.modal .modal-footer button.btn-primary').click();
+        assert.strictEqual($('.modal').length, 0, 'no confirm modal should be displayed');
+
+        assert.verifySteps(['read', 'unlink']);
+        form.destroy();
+    });
+
     QUnit.test('empty required fields cannot be saved', function (assert) {
         assert.expect(5);
 

addons/web/static/tests/views/kanban_tests.js

@@ -649,9 +649,8 @@ QUnit.module('Views', {
     });
 
     QUnit.test('delete a column in grouped on m2o', function (assert) {
-        assert.expect(21);
+        assert.expect(25);
 
-        var nbRPCs = 0;
         var kanban = createView({
             View: KanbanView,
             model: 'partner',
@@ -664,9 +663,11 @@ QUnit.module('Views', {
                     '</kanban>',
             groupBy: ['product_id'],
             mockRPC: function (route, args) {
-                nbRPCs++;
+                if (args.method) {
+                    assert.step(args.method);
+                }
                 return this._super(route, args);
-            }
+            },
         });
 
         // check the initial rendering
@@ -717,6 +718,7 @@ QUnit.module('Views', {
                         "should not be able to archive the records");
         assert.ok(!kanban.$('.o_kanban_header:first .o_kanban_config .o_column_unarchive').length,
                         "should not be able to restore the records");
+        assert.verifySteps(['read_group', 'unlink', 'read_group']);
         kanban.destroy();
     });