public function testShouldGetDirectSuccessors()
{
$nodeA = new MyNode(0, 0);
$nodeB = new MyNode(1, 1);
$nodeC = new MyNode(2, 2);
$nodeD = new MyNode(3, 3);
$distance = 1;
$this->sut->addLink(new Link($nodeA, $nodeB, $distance));
$this->sut->addLink(new Link($nodeA, $nodeC, $distance));
$this->sut->addLink(new Link($nodeB, $nodeD, $distance));
$nodeADirectSuccessors = $this->sut->getDirectSuccessors($nodeA);
$nodeBDirectSuccessors = $this->sut->getDirectSuccessors($nodeB);
$nodeCDirectSuccessors = $this->sut->getDirectSuccessors($nodeC);
$nodeDDirectSuccessors = $this->sut->getDirectSuccessors($nodeD);
$this->assertCount(2, $nodeADirectSuccessors);
$this->assertCount(1, $nodeBDirectSuccessors);
$this->assertCount(0, $nodeCDirectSuccessors);
$this->assertCount(0, $nodeDDirectSuccessors);
foreach ($nodeADirectSuccessors as $successor) {
$this->assertTrue($successor->getID() === $nodeB->getID() || $successor->getID() === $nodeC->getID());
}
$this->assertSame($nodeD->getID(), $nodeBDirectSuccessors[0]->getID());
}
