python - pytest 属性错误 : "function object has no attribute" when referencing fixture in Python 3

Question

我有一个模型和一个要测试的 Controller :

class Model:

    def __init__(self):
        self.display = ""

    def set_display(self, display):
        self.display = display

import pytest
from model import Model
from controller import Controller

@pytest.fixture
def model():
    return Model()

@pytest.fixture
def controller(model):
    return Controller(model)

def test_clear_button(controller):
    controller.button_pressed("4")
    controller.button_pressed("2")
    controller.button_pressed("C")
    assert model.display == "0"

E AttributeError: 'function' 对象没有属性 'display'

以上是我每次运行测试时遇到的错误/失败。

class Controller:

    def __init__(self, model):
        self.model = model

    def button_pressed(self, button_label):
        pass

Answer 1

根据 pytest ，通过做:

@pytest.fixture
def model():
    return Model()

然后:

@pytest.fixture
def controller(model):
    return Controller(model)

您定义了一个名为 controller 的 fixture，它引用另一个名为 model 的 fixture 来在 Controller< 的实例上定义 model/类。因此，您似乎没有正确引用 model:

def test_clear_button(controller):
    controller.button_pressed("4")
    controller.button_pressed("2")
    controller.button_pressed("C")
    assert controller.model.display == "0"

或者，或者:

def test_clear_button(controller, model):
    controller.button_pressed("4")
    controller.button_pressed("2")
    controller.button_pressed("C")
    assert model.display == "0"