public function testEquals()
 {
     parent::testEquals();
     $productA = new Product();
     $productB = new Product();
     $this->assertFalse($productA->equals($productB));
     $productA = Product::findOne(1);
     $productB = Product::findOne(2);
     $this->assertFalse($productA->equals($productB));
     $productB = Product::findOne(1);
     $this->assertTrue($productA->equals($productB));
 }