Pytest 因 AttributeError 失败：“str”对象没有属性“x”

Question

我无法通过考试。当我运行代码时，它似乎可以找到，但在 pytest 中它失败了：

desk.py

class Dimension:
    x = 0
    y = 0
    z = 0
    
    def __init__(self, x, y, z):
        self.x = x
        self.y = y
        self.z = z

class Desk:
    def __init__(self, dimension):
        self.dimension = dimension

    @property
    def dimension(self):
        return self.__dimension

    @dimension.setter
    def dimension(self, d):
        s = d.split(".")
        self.__dimension = Dimension(int(s[0]), int(s[1]), int(s[2]))

    @property
    def is_large(self):
        if self.dimension.x > 100:
             return True
        return False

test_desk.py

...
def test_is_large():
    desk = Desk("5.5.5")
    assert desk.is_large == False
...

我收到AttributeError: 'str' object has no attribute 'x'

如果我更改为 getter 和 setter 方法，它可以找到，但我想使用装饰器。

更新： 我使用python3 -m pytest 使用 python3 运行 pytest，它工作正常

Answer 1

这是 self.__dimension 的双下划线。阅读：What is the difference in python attributes with underscore in front and back

还有这个：How to access "__" (double underscore) variables in methods added to a class

将 self.__dimension 更改为 self._dimension 即可。

编辑：不是下划线。您的代码在 Python3 中完美运行。在 Python2 中，我以这种方式工作：

class Dimension:
    x = 0
    y = 0
    z = 0
    def __init__(self, x, y, z):
        self.x = 0
        self.y = 0
        self.z = 0

class Desk:
    def __init__(self, dimension):
        s = dimension.split(".")
        self.__dimension = Dimension(int(s[0]), int(s[1]), int(s[2]))
    @property
    def dimension(self):
        return self.__dimension
    @dimension.setter
    def dimension(self, d):
        s = d.split(".")
        self.__dimension = Dimension(int(s[0]), int(s[1]), int(s[2]))
    @property
    def is_large(self):
        if self.dimension.x > 100:
             return True
        return False