public function testSetDataAttrib()
 {
     $tag = new Tag(['tag' => 'div']);
     $tag->data('foo', 'bar');
     $this->assertEquals('bar', $tag->getAttrib('data-foo'));
 }
 /**
  * 
  * @param string $title
  * @param string $placement left|right|top|bottom
  * @return \PhpBootstrap\Html\Tag
  */
 public function tooltip($title, $placement = 'left')
 {
     $this->tag->data('toggle', 'tooltip')->data('placement', $placement)->setAttrib('title', $title);
     return $this;
 }