public function testHasPrevSibling() { Table9Peer::doDeleteAll(); $t0 = new Table9(); $t1 = new Table9(); $t1->setTitle('t1')->setLeftValue(1)->setRightValue(6)->save(); $t2 = new Table9(); $t2->setTitle('t2')->setLeftValue(2)->setRightValue(3)->save(); $t3 = new Table9(); $t3->setTitle('t3')->setLeftValue(4)->setRightValue(5)->save(); $this->assertFalse($t0->hasPrevSibling(), 'empty node has no previous sibling'); $this->assertFalse($t1->hasPrevSibling(), 'root node has no previous sibling'); $this->assertFalse($t2->hasPrevSibling(), 'first sibling has no previous sibling'); $this->assertTrue($t3->hasPrevSibling(), 'not first sibling has a previous siblingt'); }