python - 尝试运行测试时 Pytest 给我一个错误

Question

不知道为什么测试不起作用。在我看来，我做的一切都是正确的(根据文档)。

在unittest中一切正常，但pytest更先进，所以我想改变。

import requests
import pytest

def get_historical_currency_rate(currency_code, currency_date) :
    url = requests.get(
     f'http://api.nbp.pl/api/exchangerates/rates/a/{currency_code}/{currency_date}/?format=json')
    r = url.json()
    rate = r['rates'][0]['mid']
    return round(rate, 2)


@pytest.fixture
def currency_loop_helper():
    dates_rate = ['2018-05-25', '2017-02-20', '2013-12-11']
    currencies_codes = ['JPY', 'AUD', 'GBP']
    expected_rates = [0.03, 3.76, 4.44]
    actual_rates = []
    for i in range(len(dates_rate)):
        result = get_historical_currency_rate(currencies_codes[i], dates_rate[i])
        actual_rates.append(result)
    actual_list = [(a, b) for a, b in zip(actual_rates, expected_rates)]
    return actual_list


@pytest.mark.parametrize('expected, actual', currency_loop_helper)
def test_currency_rate_equal(expected, actual):
    assert expected == actual

<小时/>

ERRORS 
 "...ParameterSet.extract_from(x, force_tuple=force_tuple) for x in argvalues
E   TypeError: 'function' object is not iterable
=============================== warnings summary ===============================
/usr/lib/python3/dist-packages/urllib3/util/selectors.py:14
  /usr/lib/python3/dist-packages/urllib3/util/selectors.py:14: DeprecationWarning:Using or importing the ABCs from 'collections' instead of from 'collections.abc' is deprecated, and in 3.8 it will stop working
    from collections import namedtuple, Mapping

/usr/lib/python3/dist-packages/socks.py:58
  /usr/lib/python3/dist-packages/socks.py:58: DeprecationWarning: Using or importing the ABCs from 'collections' instead of from 'collections.abc' is deprecated, and in 3.8 it will stop working
    from collections import Callable

Answer 1

我相信您不需要将 currency_loop_helper 设为固定装置。然后，您可以通过 test_currency_rate_equal 调用参数化装饰器中的函数。建议的代码更改如下所示:

import requests
import pytest

def get_historical_currency_rate(currency_code, currency_date) :
    url = requests.get(
     f'http://api.nbp.pl/api/exchangerates/rates/a/{currency_code}/{currency_date}/?format=json')
    r = url.json()
    rate = r['rates'][0]['mid']
    return round(rate, 2)


def currency_loop_helper():
    dates_rate = ['2018-05-25', '2017-02-20', '2013-12-11']
    currencies_codes = ['JPY', 'AUD', 'GBP']
    expected_rates = [0.03, 3.76, 4.44]
    actual_rates = []
    for i in range(len(dates_rate)):
        result = get_historical_currency_rate(currencies_codes[i], dates_rate[i])
        actual_rates.append(result)
    actual_list = [(a, b) for a, b in zip(actual_rates, expected_rates)]
    return actual_list


@pytest.mark.parametrize('expected, actual', currency_loop_helper())
def test_currency_rate_equal(expected, actual):
    assert expected == actual