如何使用 py.test 对多个项目执行多个测试

Question

我是 python 和 py.test 的新手。 我正在寻找一种对多个项目运行多个测试的方法，但找不到它。 我相信当你知道如何去做时，这很简单。

我已经简化了我想要做的事情，使其易于理解。

如果我有一个 Test 类定义了一系列这样的测试：

class SeriesOfTests:
    def test_greater_than_30(self, itemNo):
        assert (itemNo > 30), "not greather than 30"
    def test_lesser_than_30(self, itemNo):
        assert (itemNo < 30), "not lesser thant 30"
    def test_modulo_2(self, itemNo):
        assert (itemNo % 2) == 0, "not divisible by 2"

我想对从以下函数获得的每个项目执行此 SeriesOfTest：

def getItemNo():
    return [0,11,33]

我试图获得的结果是这样的：

RESULT : 
Test "itemNo = 0"
  - test_greater_than_30 = failed
  - test_lesser_than_30 = success
  - test_modulo_2 = success

Test "itemNo = 11"
  - test_greater_than_30 = failed
  - test_lesser_than_30 = success
  - test_modulo_2 = failed

Test "itemNo = 33"
  - test_greater_than_30 = success
  - test_lesser_than_30 = failed
  - test_modulo_2 = failed

我怎样才能用 py.test 做到这一点？

比你们（还有女孩）

安德烈

Answer 1

使用夹具：

import pytest

@pytest.fixture(params=[0, 11, 33])
def itemNo(request):
    return request.param

def test_greater_than_30(itemNo):
    assert (itemNo > 30), "not greather than 30"
def test_lesser_than_30(itemNo):
    assert (itemNo < 30), "not lesser thant 30"
def test_modulo_2(itemNo):
    assert (itemNo % 2) == 0, "not divisible by 2"

注意：fixture 函数的名称（ itemNo ）和测试函数的参数名称应该相同。

请参阅演示运行。

---

更新

import pytest

class FunctionWrapper(str):
    def __init__(self, f):
        self.f = f
    def __call__(self, *args, **kwargs):
        return self.f(*args, **kwargs)
    def __str__(self):
        return self.f.__name__

def greater_than_30(itemNo):
    assert (itemNo > 30), "not greater than 30"
def lesser_than_30(itemNo):
    assert (itemNo < 30), "not lesser thant 30"
def modulo_2(itemNo):
    assert (itemNo % 2) == 0, "not divisible by 2"

@pytest.fixture(params=[0, 11, 33])
def itemNo(request):
    return request.param

@pytest.fixture(params=map(FunctionWrapper, [
    greater_than_30, lesser_than_30, modulo_2
]))
def assertion_func(request):
    return request.param

def test_item_no(itemNo, assertion_func):
    assertion_func(itemNo)

使用-v --tb=no选项。

例如：

============================= test session starts ==============================
platform linux2 -- Python 2.7.5 -- pytest-2.3.5 -- /usr/bin/python
collected 9 items

test_sample.py:26: test_item_no[0-greater_than_30] FAILED
test_sample.py:26: test_item_no[0-lesser_than_30] PASSED
test_sample.py:26: test_item_no[0-modulo_2] PASSED
test_sample.py:26: test_item_no[11-greater_than_30] FAILED
test_sample.py:26: test_item_no[11-lesser_than_30] PASSED
test_sample.py:26: test_item_no[11-modulo_2] FAILED
test_sample.py:26: test_item_no[33-greater_than_30] PASSED
test_sample.py:26: test_item_no[33-lesser_than_30] FAILED
test_sample.py:26: test_item_no[33-modulo_2] FAILED

====================== 5 failed, 4 passed in 0.03 seconds ======================

见http://asciinema.org/a/6562

Answer 2

忘记之前的答案。 鉴于您需要按值对测试进行分组，您可以使用场景。 我刚刚改编了文档中的示例：

import pytest

def pytest_generate_tests(metafunc):
    idlist = []
    argvalues = []
    for scenario in metafunc.cls.scenarios:
        idlist.append(scenario[0])
        items = scenario[1].items()
        argnames = [x[0] for x in items]
        argvalues.append(([x[1] for x in items]))
    metafunc.parametrize(argnames, argvalues, ids=idlist, scope="class")

scenario1 = ('itemNo = 0', {'itemNo': 0})
scenario2 = ('itemNo = 11', {'itemNo': 11})
scenario3 = ('itemNo = 33', {'itemNo': 33})

class TestSeries:
    scenarios = [scenario1, scenario2, scenario3]
    
    def test_greater_than_30(self, itemNo):
        assert (itemNo > 30), "not greather than 30"
    def test_lesser_than_30(self, itemNo):
        assert (itemNo < 30), "not lesser thant 30"
    def test_modulo_2(self, itemNo):
        assert (itemNo % 2) == 0, "not divisible by 2"

输出是：

$ py.test -v
============ test session starts ==============================================
platform linux2 -- Python 2.7.4 -- pytest-2.4.2 -- /home/jose/.virtualenvs/pytest1/bin/python
collected 9 items 

test_first.py:23: TestSeries.test_greater_than_30[itemNo = 0] FAILED
test_first.py:25: TestSeries.test_lesser_than_30[itemNo = 0] PASSED
test_first.py:27: TestSeries.test_modulo_2[itemNo = 0] PASSED
test_first.py:23: TestSeries.test_greater_than_30[itemNo = 11] FAILED
test_first.py:25: TestSeries.test_lesser_than_30[itemNo = 11] PASSED
test_first.py:27: TestSeries.test_modulo_2[itemNo = 11] FAILED
test_first.py:23: TestSeries.test_greater_than_30[itemNo = 33] PASSED
test_first.py:25: TestSeries.test_lesser_than_30[itemNo = 33] FAILED
test_first.py:27: TestSeries.test_modulo_2[itemNo = 33] FAILED

我认为这是你能得到的最接近的。