如何更改 python function 变量的值以进行单元测试

Question

给定以下假设代码，如何更改变量discount和is_active的值，以便测试 function price_discount以获得不同的预期返回值？

discounts.py

import active_member

#returns a 20% discount value for active members 
def price_discount(price, membership_id):
    discount = 0.2
    is_active = active_member(membership_id)
    if is_active:
        price_discount = price * discount
    else:
        price_discount = 0

    return price_discount

test_discounts.py

import discounts

def test_price_discount():
    test = discounts.price_discount(50.00, 'D01910')
    assert test == some_expected_value

Answer 1

看看参数化

您的代码应如下所示：

import discounts


parameters = [
    { 
        "price": 50, 
        "membership": "D01910",
        "expected_value": 0
    },
    { 
        "price": 1, 
        "membership": "A",
        "expected_value": 0
    },
    { 
        "price": 2, 
        "membership": "B",
        "expected_value": 0
    }
]

@pytest.mark.parametrize("parameter", parameters)
def test_price_discount(parameter):
    actual_value = discounts.price_discount(parameter['price'], parameter['membership'])
    assert actual_value == parameter["expected_value"]