List: empty message should be hidden when new item is inserted to empty store (T1277567)

Author: Zedwag

packages/devextreme/js/__internal/ui/collection/m_collection_widget.live_update.ts

@@ -1,7 +1,6 @@
 import domAdapter from '@js/core/dom_adapter';
 import $ from '@js/core/renderer';
 import { findChanges } from '@js/core/utils/array_compare';
-import { noop } from '@js/core/utils/common';
 import { when } from '@js/core/utils/deferred';
 import { extend } from '@js/core/utils/extend';
 import { each } from '@js/core/utils/iterator';
@@ -191,7 +190,9 @@ export default CollectionWidget.inherit({
     }
   },
 
-  _afterItemElementInserted: noop,
+  _afterItemElementInserted(): void {
+    this._renderEmptyMessage();
+  },
 
   _removeByChange(keyInfo, items, change, isPartialRefresh) {
     const index = isPartialRefresh ? change.index : indexByKey(keyInfo, items, change.key);

packages/devextreme/testing/tests/DevExpress.ui.widgets/listParts/liveUpdateTests.js

@@ -6,6 +6,7 @@ import 'ui/list';
 
 const LIST_ITEM_CLASS = 'dx-list-item';
 const LIST_GROUP_CLASS = 'dx-list-group';
+const EMPTY_MESSAGE_CLASS = 'dx-empty-message';
 
 QUnit.module('live update', {
     beforeEach: function() {
@@ -208,6 +209,26 @@ QUnit.module('live update', {
         assert.deepEqual(this.itemDeletedSpy.firstCall.args[0].itemData.id, pushData[0].key, 'check removed item key');
     });
 
+    QUnit.test('Empty message should be hidden after new element is pushed to empty store (T1277567)', function(assert) {
+        const clock = sinon.useFakeTimers();
+        const list = this.createList({
+            dataSource: new DataSource({
+                key: 'id',
+                store: []
+            })
+        });
+        const store = list.getDataSource().store();
+
+        assert.strictEqual(list.$element().find(`.${EMPTY_MESSAGE_CLASS}`).length, 1, 'empty message is shown');
+
+        store.push([{ type: 'insert', data: { id: 2 }, index: 0 }]);
+        clock.tick(0);
+
+        assert.strictEqual(list.$element().find(`.${EMPTY_MESSAGE_CLASS}`).length, 0, 'empty message is hidden');
+
+        clock.restore();
+    });
+
     QUnit.test('remove two items', function(assert) {
         const store = this.createList({
             dataSource: {