@Test
public void testWritesIntoDefaultShard() throws Exception {

    initEmptyDatastores();
    final DOMDataTreeIdentifier configRoot =
            new DOMDataTreeIdentifier(LogicalDatastoreType.CONFIGURATION, YangInstanceIdentifier.empty());
    final DOMDataTreeProducer producer = leaderShardFactory.createProducer(Collections.singleton(configRoot));
    final DOMDataTreeCursorAwareTransaction tx = producer.createTransaction(true);
    final DOMDataTreeWriteCursor cursor =
            tx.createCursor(new DOMDataTreeIdentifier(
                    LogicalDatastoreType.CONFIGURATION, YangInstanceIdentifier.empty()));
    Assert.assertNotNull(cursor);
    final ContainerNode test =
            ImmutableContainerNodeBuilder.create()
                    .withNodeIdentifier(new NodeIdentifier(TestModel.TEST_QNAME)).build();
    cursor.write(test.getIdentifier(), test);
    cursor.close();
    tx.commit().get();
}