/**

     * Test export and recover with children.

     */

    public function test_get_data_with_children() {

        $writer = $this->get_writer_instance();

        $context = \context_system::instance();

        $writer->set_context($context)

            ->export_data(['a'], (object) ['parent' => true])

            ->export_data(['a', 'b'], (object) ['parent' => false]);

        $this->assertTrue($writer->get_data(['a'])->parent);

        $this->assertFalse($writer->get_data(['a', 'b'])->parent);

        $this->assertSame([], $writer->get_data(['a', 'b', 'c']));

    }