Dollar类的对象无法转换为int


Object of class Dollar could not be converted to int

我正在阅读作者Kent Beck的《示例测试驱动开发》一书。

我正在尝试用php编写一个类似的函数,但不理解其中的步骤。

原始功能:

测试功能:

public void testEquality() {
    assertTrue(new Dollar(5).equals(new Dollar(5)));
    assertFalse(new Dollar(5).equals(new Dollar(6)));
}

类功能:

public boolean equals(Object object) {
   Dollar dollar = (Dollar) object;
   return amount == dollar.amount;
}

我的代码:

测试功能:

public function setup() {
   $this->dollarFive = new Dollar(5);
}
public function testEquality() {
    $this->assertTrue($this->dollarFive->equals(new Dollar(5)));
}

类函数:

class Dollar
{   
  public function __construct($amount) {
    $this->amount = (int) $amount;
  }
   public function equals(Dollar $object) {
     $this->Object = $object;
     return $this->amount == $this->Object;
   }    
}

在执行测试用例时,我得到了以下错误。

Dollar类的对象无法转换为int

需要一些帮助。我该怎么解决这个问题?

return $this->amount == $this->Object;

$this->amount是int,$this->Object不是int。你试图相互比较,这样你就会得到

Dollar类的对象无法转换为int

你可能是指

return $this->amount == $this->Object->amount;

然而,在你的课堂中也有一些奇怪的东西

class Dollar {
  public $amount = 0; // <-- forgotten
  public function __construct($amount) {
    $this->amount = (int) $amount;
  }
   public function equals(Dollar $object) {
     $this->Object = $object; // <--- ?!?
     return $this->amount == $this->Object;
   }    
}

你可能只想要

   public function equals(Dollar $object) {
     return $this->amount == $object->amount;
   }