QUnit.test('Undefined lang', function (assert) {
    var chart = Highcharts.chart('container', {
        lang: {
            loading: undefined
        },
        series: [
            {
                data: [1, 2, 3]
            }
        ]
    });

    chart.showLoading();

    assert.equal(
        chart.loadingDiv.childNodes[0].innerHTML,
        '',
        'undefined value is not draw'
    );
});
