public function testGraphDirectedLoop()
{
// 1 -> 1
$graph = new Graph();
$graph->createVertex(1)->createEdgeTo($v1 = $graph->getVertex(1));
$alg = new AlgorithmLoop($graph);
$this->assertTrue($alg->hasLoop());
$this->assertTrue($alg->hasLoopVertex($v1));
}
/**
* checks whether this walk HAS a loop (single edge connecting vertex A with vertex A again)
*
* The following Walk is NOT a valid loop, but it contains a valid loop:
*
* /->3
* |
* 1 -> 2 -\
* ^ |
* \--/
*
* @return boolean
* @uses AlgorithmLoop::hasLoop()
* @see self::isLoop()
*/
public function hasLoop()
{
$alg = new AlgorithmLoop($this->walk);
return $alg->hasLoop();
}