public function testIsChildOf()
 {
     $node = MultipleTree::findOne(26);
     $this->assertTrue($node->isChildOf(MultipleTree::findOne(25)));
     $this->assertTrue($node->isChildOf(MultipleTree::findOne(23)));
     $this->assertFalse($node->isChildOf(MultipleTree::findOne(3)));
     $this->assertFalse($node->isChildOf(MultipleTree::findOne(1)));
 }
 public function testLeaves()
 {
     $this->assertEquals(require __DIR__ . '/data/test-leaves-query.php', ArrayHelper::toArray(Tree::find()->leaves()->all()));
     $this->assertEquals(require __DIR__ . '/data/test-leaves-multiple-tree-query.php', ArrayHelper::toArray(MultipleTree::find()->leaves()->all()));
 }