pytest：如何从文件中读取装置列表？

我想通过pytest（via）断言主机上是否存在包。 我有一个文本文件中应该存在的包列表，我可以读取并放入数组中。我想用这个数组来参数化一个装置，这样我就可以在测试中使用它了

比如：

@pytest.fixture
def packages():
    listfile = open("list.txt", "r")
    packages = listfile.read().splitlines()
   return packages

然后使用它来参数化测试：

@pytest.mark.parametrize("name", packages)
    def test_packages(host, name):
    assert host.package(name).is_installed

我得到的错误是

    /home/becker/molecule/local/lib/python2.7/site-packages/pluggy/__init__.py:617: in __call__
    return self._hookexec(self, self._nonwrappers + self._wrappers, kwargs)
/home/becker/molecule/local/lib/python2.7/site-packages/pluggy/__init__.py:222: in _hookexec
    return self._inner_hookexec(hook, methods, kwargs)
/home/becker/molecule/local/lib/python2.7/site-packages/pluggy/__init__.py:216: in <lambda>
    firstresult=hook.spec_opts.get('firstresult'),
/home/becker/molecule/local/lib/python2.7/site-packages/_pytest/python.py:197: in pytest_pycollect_makeitem
    res = list(collector._genfunctions(name, obj))
/home/becker/molecule/local/lib/python2.7/site-packages/_pytest/python.py:390: in _genfunctions
    self.ihook.pytest_generate_tests(metafunc=metafunc)
/home/becker/molecule/local/lib/python2.7/site-packages/pluggy/__init__.py:617: in __call__
    return self._hookexec(self, self._nonwrappers + self._wrappers, kwargs)
/home/becker/molecule/local/lib/python2.7/site-packages/pluggy/__init__.py:222: in _hookexec
    return self._inner_hookexec(hook, methods, kwargs)
/home/becker/molecule/local/lib/python2.7/site-packages/pluggy/__init__.py:216: in <lambda>
    firstresult=hook.spec_opts.get('firstresult'),
/home/becker/molecule/local/lib/python2.7/site-packages/_pytest/python.py:122: in pytest_generate_tests
    metafunc.parametrize(*marker.args, **marker.kwargs)
/home/becker/molecule/local/lib/python2.7/site-packages/_pytest/python.py:809: in parametrize
    argnames, argvalues, self.function, self.config)
/home/becker/molecule/local/lib/python2.7/site-packages/_pytest/mark/structures.py:102: in _for_parametrize
    for x in argvalues]
E   TypeError: 'function' object is not iterable
!!!!!!!!!!!!!!!!!!! Interrupted: 1 errors during collection !!!!!!!!!!!!!!!!!!!!
=========================== 1 error in 0.41 seconds ============================

/home/becker/molecular/local/lib/python2.7/site-packages/pluggy/__-init.py:617:in-call__
返回self.\u hookexec（self，self.\u非包装器+self.\u包装器，kwargs）
/home/becker/molecule/local/lib/python2.7/site-packages/pluggy/__;u-init___;.py:222:in hookexec
返回self.\u inner\u hookexec（钩子、方法、kwargs）
/home/becker/molecule/local/lib/python2.7/site-packages/pluggy/__-init.py:216:in
firstresult=hook.spec_opts.get（'firstresult'），
/home/becker/molecule/local/lib/python2.7/site-packages/\u-pytest/python.py:197:in-pytest\u-pycollect\u-makeitem
res=列表（收集器类型函数（名称，obj））
/home/becker/molecule/local/lib/python2.7/site-packages/_-pytest/python.py:390:in _-genfunctions
self.ihook.pytest\u generate\u测试（metafunc=metafunc）
/home/becker/molecule/local/lib/python2.7/site-packages/pluggy/__-init.py:617:in-u-call__
返回self.\u hookexec（self，self.\u非包装器+self.\u包装器，kwargs）
/home/becker/molecule/local/lib/python2.7/site-packages/pluggy/__;u-init___;.py:222:in hookexec
返回self.\u inner\u hookexec（钩子、方法、kwargs）
/home/becker/molecule/local/lib/python2.7/site-packages/pluggy/__-init.py:216:in
firstresult=hook.spec_opts.get（'firstresult'），
/home/becker/molecule/local/lib/python2.7/site-packages/\u-pytest/python.py:122:in-pytest\u-generate\u-tests
元函数参数化（*marker.args，**marker.kwargs）
/home/becker/molecule/local/lib/python2.7/site-packages/_-pytest/python.py:809:in参数化
argName、argvalues、self.function、self.config）
/home/becker/molecule/local/lib/python2.7/site packages/_pytest/mark/structures.py:102:in用于参数化
对于argvalues中的x]
E TypeError:“函数”对象不可编辑
!!!!!!!!!!!!!!!!!!! 中断：收集过程中出现1个错误！！！！！！！！！！！！！！！！！！！！
========================================0.41秒内出现1个错误============================

目前，

pytest

不支持将夹具作为参数传递到

pytest.mark.parametrize

。您可以在中跟踪相关讨论的当前状态

然而，固定装置也是功能。因此，正如注释中所建议的，您可以在

parametrize

中调用fixture函数：

@pytest.mark.parametrize("name", packages())
def test_packages(host, name):
    ...

---

pytest

不支持将夹具作为参数传递到

parametrize

（请参阅）。当

参数化

展开时，夹具还没有进行评估。作为一种解决方法，您可以将fixture作为普通函数调用：

@pytest.mark.parametrize（“name”，packages（））

，因为

packages

不需要任何其他参数。@hoefling感谢您的建议。这个变通方法正是我想要的。你想继续回答这个问题吗？