Tests for a valid HTML ID for a block.
function testHtmlId() {
$this
->drupalGet('');
$this
->assertRaw('id="block-test-id-block"', 'HTML ID for test block is valid.');
$elements = $this
->xpath('//div[contains(@class, :div-class)]/div/ul[contains(@class, :ul-class)]/li', array(
':div-class' => 'block-system',
':ul-class' => 'menu',
));
$this
->assertTrue(!empty($elements), 'The proper block markup was found.');
}