public function testTagCollection()
{
$material = new material();
$this->assertFalse($material->containsTag('t'));
$material->addTag('t');
$this->assertTrue($material->containsTag('t'));
$material->removeTag('t');
$this->assertFalse($material->containsTag('t'));
//Repeat Tag
$this->assertFalse($material->containsTag('t'));
$material->addTag('t');
$material->addTag('t');
$this->assertTrue($material->containsTag('t'));
$material->removeTag('t');
$this->assertFalse($material->containsTag('t'));
$this->assertFalse($material->removeTag('t'));
//containsAllTag and containsAnyTag
$material->addTag('t1');
$material->addTag('t2');
$material->addTag('t3');
$this->assertTrue($material->containsAnyTag(array('t0', 't2')));
$this->assertTrue($material->containsAnyTag(array('t2', 't3')));
$this->assertFalse($material->containsAnyTag(array('t0', 't4')));
$this->assertTrue($material->containsAllTags(array('t1', 't2')));
$this->assertTrue($material->containsAllTags(array('t1')));
$this->assertFalse($material->containsAllTags(array('t0', 't2')));
$this->assertFalse($material->containsAllTags(array('t0', 't1', 't2', 't3')));
}