public function testext_invoice_sort_by_date_asc()
{
$actual = ext_invoice_sort_by_date_asc(array('timestamp' => 10), array('timestamp' => 10));
$this->assertEquals(0, $actual);
$actual = ext_invoice_sort_by_date_asc(array('timestamp' => 10), array('timestamp' => 20));
$this->assertEquals(-1, $actual);
$actual = ext_invoice_sort_by_date_asc(array('timestamp' => 20), array('timestamp' => 10));
$this->assertEquals(1, $actual);
$input = array(0 => array('desc' => '2', 'timestamp' => 20), 1 => array('desc' => '1', 'timestamp' => 10), 2 => array('desc' => '5', 'timestamp' => 50), 3 => array('desc' => '3', 'timestamp' => 30), 4 => array('desc' => '4', 'timestamp' => 40));
uasort($input, 'ext_invoice_sort_by_date_asc');
$this->assertEquals($input, array(1 => array('desc' => '1', 'timestamp' => 10), 0 => array('desc' => '2', 'timestamp' => 20), 3 => array('desc' => '3', 'timestamp' => 30), 4 => array('desc' => '4', 'timestamp' => 40), 2 => array('desc' => '5', 'timestamp' => 50)));
}