[FIX] web: pivot view should respect the groupbys from the search view

Before this commit, groupbys from the search view were totally ignored.

addons/web/static/src/js/views/pivot/pivot_model.js

@@ -198,6 +198,10 @@ var PivotModel = AbstractModel.extend({
             sortedColumn: this.data.sorted_column,
         };
     },
+    /**
+     * @param {string} id
+     * @returns {object}
+     */
     getHeader: function (id) {
         return this.data.headers[id];
     },
@@ -246,11 +250,20 @@ var PivotModel = AbstractModel.extend({
         } else {
             this.data.domain = this.initialDomain;
         }
+        if ('groupBy' in params) {
+            this.data.groupedBy = params.groupBy;
+        }
 
         return this._loadData(params).then(function () {
-            self._updateTree(old_row_root, self.data.main_row.root);
-            var new_groupby_length = self._getHeaderDepth(self.data.main_row.root) - 1;
-            self.data.main_row.groupbys = old_row_root.groupbys.slice(0, new_groupby_length);
+            var new_groupby_length;
+            if (!('groupBy' in params)) {
+                // we only update the row groupbys according to the old groupbys
+                // if we don't have the key 'groupBy' in params.  In that case,
+                // we want to have the full open state for the groupbys.
+                self._updateTree(old_row_root, self.data.main_row.root);
+                new_groupby_length = self._getHeaderDepth(self.data.main_row.root) - 1;
+                self.data.main_row.groupbys = old_row_root.groupbys.slice(0, new_groupby_length);
+            }
 
             self._updateTree(old_col_root, self.data.main_col.root);
             new_groupby_length = self._getHeaderDepth(self.data.main_col.root) - 1;
@@ -694,8 +707,9 @@ var PivotModel = AbstractModel.extend({
                     break;
                 }
             }
-            if (tree) this._updateTree(tree, new_tree.children[i]);
-            else {
+            if (tree) {
+                this._updateTree(tree, new_tree.children[i]);
+            } else {
                 new_tree.children[i].expanded = false;
                 new_tree.children[i].children = [];
             }

addons/web/static/test/views/pivot_tests.js

@@ -426,4 +426,30 @@ QUnit.module('Views', {
         pivot.destroy();
     });
 
+    QUnit.test('can be grouped with the update function', function (assert) {
+        assert.expect(4);
+
+        var pivot = createView({
+            View: PivotView,
+            model: "partner",
+            data: this.data,
+            arch: '<pivot>' +
+                        '<field name="foo" type="measure"/>' +
+                '</pivot>',
+        });
+
+        assert.strictEqual(pivot.$('.o_pivot_cell_value').length, 1,
+            "should have only 1 cell");
+        assert.strictEqual(pivot.$('tbody tr').length, 1,
+            "should have 1 rows");
+
+        pivot.update({groupBy: ['product_id']});
+
+        assert.strictEqual(pivot.$('.o_pivot_cell_value').length, 3,
+            "should have 3 cells");
+        assert.strictEqual(pivot.$('tbody tr').length, 3,
+            "should have 3 rows");
+        pivot.destroy();
+    });
+
 });});