如何在pytest中对固定装置施加顺序?

How to impose order on fixtures in pytest?

我正在尝试使用 pytest-dependency 使 fixtures 按顺序发生,无论它们如何命名,也无论它们在测试的参数列表。

我需要这个的原因是创建需要初始化的固定装置,它依赖于其他需要初始化的固定装置,并且它们必须按顺序发生。我有很多这样的东西,我不想依赖命名或参数列表中的顺序。

我也不想使用 pytest_sessionstart,因为它不能接受 fixture 输入,这会导致非常不干净的代码。


the doc 中的简单示例展示了如何为测试创建编程依赖项:

import pytest

@pytest.mark.dependency()
@pytest.mark.xfail(reason="deliberate fail")
def test_a():
    assert False

@pytest.mark.dependency()
def test_b():
    pass

@pytest.mark.dependency(depends=["test_a"])
def test_c():
    pass

@pytest.mark.dependency(depends=["test_b"])
def test_d():
    pass

@pytest.mark.dependency(depends=["test_b", "test_c"])
def test_e():
    pass

这适用于输出:

============================= test session starts =============================
collecting ... collected 5 items

test_sanity.py::test_z XFAIL (deliberate fail)                           [ 20%]
@pytest.mark.dependency()
    @pytest.mark.xfail(reason="deliberate fail")
    def test_z():
>       assert False
E       assert False

test_sanity.py:6: AssertionError

test_sanity.py::test_x PASSED                                            [ 40%]
test_sanity.py::test_c SKIPPED (test_c depends on test_z)                [ 60%]
Skipped: test_c depends on test_z

test_sanity.py::test_d PASSED                                            [ 80%]
test_sanity.py::test_w SKIPPED (test_w depends on test_c)                [100%]
Skipped: test_w depends on test_c


=================== 2 passed, 2 skipped, 1 xfailed in 0.05s ===================

现在我想对灯具做同样的事情。

我的尝试:

conftest.py:

import pytest

pytest_plugins = ["dependency"]


@pytest.mark.dependency()
@pytest.fixture(autouse=True)
def zzzshould_happen_first():
    assert False


@pytest.mark.dependency(depends=["zzzshould_happen_first"])
@pytest.fixture(autouse=True)
def should_happen_last():
    assert False

test_sanity.py:

def test_nothing():
    assert True

产出

test_sanity.py::test_nothing ERROR                                       [100%]
test setup failed
@pytest.mark.dependency(depends=["zzzshould_happen_first"])
    @pytest.fixture(autouse=True)
    def should_happen_last():
>       assert False
E       assert False

conftest.py:15: AssertionError

我预计 zzzshould_happen_first 会出现错误。


有没有办法对灯具进行排序,这样

  1. 他们的名字被忽略
  2. 它们在参数列表中的顺序被忽略
  3. 其他pytest特性如autouse仍然可以应用

您可以直接使用 pytest 将夹具作为依赖项提供。像这样:

import pytest


@pytest.fixture(autouse=True)
def zzzshould_happen_first():
    assert False


@pytest.fixture(autouse=True)
def should_happen_last(zzzshould_happen_first):
    assert False


def test_nothing():
    assert True

它给了你想要的:

test setup failed
@pytest.fixture(autouse=True)
    def zzzshould_happen_first():
>       assert False
E       assert False

answer.py:7: AssertionError