public function testHeadAttributes()
{
$page = new SeoPage();
$page->setHeadAttributes(array('head1' => 'value1'));
$page->addHeadAttribute('head2', 'value2');
$expected = array('head1' => 'value1', 'head2' => 'value2');
$this->assertEquals($expected, $page->getHeadAttributes());
$this->assertTrue($page->hasHeadAttribute('head1'));
$page->removeHeadAttribute('head1');
$this->assertFalse($page->hasHeadAttribute('head1'));
}