Python Pytest不'；安装pytest xdist后无法识别-n选项

我已在一个正常工作的pytest环境上安装了pytest xdist：

pip install pytest-xdist

我已经收到了这个输出

Downloading/unpacking pytest-xdist
  Downloading pytest-xdist-1.10.tar.gz
  Running setup.py egg_info for package pytest-xdist

    no previously-included directories found matching '.hg'
Downloading/unpacking execnet>=1.1 (from pytest-xdist)
  Downloading execnet-1.2.0.tar.gz (163kB): 163kB downloaded
  Running setup.py egg_info for package execnet

    warning: no files found matching 'conftest.py'
Requirement already satisfied (use --upgrade to upgrade): pytest>=2.4.2 in /Users/sal/Documents/code/Python/VirtualEnv/Spring/lib/python2.7/site-packages (from pytest-xdist)
Requirement already satisfied (use --upgrade to upgrade): py>=1.4.20 in /Users/sal/Documents/code/Python/VirtualEnv/Spring/lib/python2.7/site-packages (from pytest>=2.4.2->pytest-xdist)
Installing collected packages: pytest-xdist, execnet
  Running setup.py install for pytest-xdist

    no previously-included directories found matching '.hg'
  Running setup.py install for execnet

    warning: no files found matching 'conftest.py'
Successfully installed pytest-xdist execnet
Cleaning up...

此时，我已尝试并行运行我的测试套件

py.test -n 4

但是我收到了这个输出

usage: py.test [options] [file_or_dir] [file_or_dir] [...]
py.test: error: unrecognized arguments: -n

“py.test--版本为”的输出

This is pytest version 2.6.2, imported from /Users/sal/Documents/code/Python/VirtualEnv/Spring/lib/python2.7/site-packages/pytest.pyc
setuptools registered plugins:
  pytest-capturelog-0.7 at /Users/sal/Documents/code/Python/VirtualEnv/Spring/lib/python2.7/site-packages/pytest_capturelog.pyc
  pytest-contextfixture-0.1.1 at /Users/sal/Documents/code/Python/VirtualEnv/Spring/lib/python2.7/site-packages/pytest_contextfixture.pyc
  pytest-cov-1.7.0 at /Users/sal/Documents/code/Python/VirtualEnv/Spring/lib/python2.7/site-packages/pytest_cov.pyc
  pytest-django-2.6.2 at /Users/sal/Documents/code/Python/VirtualEnv/Spring/lib/python2.7/site-packages/pytest_django/plugin.pyc
  pytest-pydev-0.1 at /Users/sal/Documents/code/Python/VirtualEnv/Spring/lib/python2.7/site-packages/pytest_pydev.pyc
  pytest-runfailed-0.3 at /Users/sal/Documents/code/Python/VirtualEnv/Spring/lib/python2.7/site-packages/pytest_runfailed.pyc

pytest xdist实际上丢失了

---

我错了什么？谢谢。

请尝试

py.test--version

并查看输出，其中解释了从何处导入内容，包括插件。很可能您没有运行您认为正在运行的

py.test

我也有同样的问题。问题不在于版本。不知何故，py.test无法看到xdist的位置。以下是对我有效的方法：

pip安装pytest--用户
pip安装pytest xdist--用户

export PATH=$HOME/.local/bin:$PATH

就像，我遇到了同样的问题。与User2411266不同，在我的案例中，解决方案是放松对

xdist

和

pytest\u xdist-1.14.dist info

由

pip3

安装的系统目录的权限

一些后台故事：为了安全起见，我在我的系统上运行了一个严格的

umask

，默认情况下禁止所有对

其他

用户的访问和对

组

用户的写访问：

$ umask
027

虽然这通常是件好事，但偶尔也会给我带来麻烦。通过

pip3

在此

umask

下安装

python xdist

：

$ sudo pip3 install pytest-xdist

…导致

pip3

禁止对非超级用户进行读取和执行访问–最好只有我一个人：

虽然

pip3

这样做并没有错，

py.test

在插件检测期间默默忽略而不是显式报告明显的权限问题（…可以说！）是错误的

通过递归地为受影响的系统目录授予

其他

用户读取和目录执行权限，这是可以解决的：

$ chmod -R o+rX /usr/lib64/python3.4/site-packages/xdist
$ chmod -R o+rX /usr/lib64/python3.4/site-packages/pytest_xdist-1.14.dist-info

命令行布丁就是证明：

$ ls -l /usr/lib64/python3.4/site-packages/xdist
drwxr-xr-x   3 root root 4.0K 2016-04-10 01:19 xdist/
$ ls -l /usr/lib64/python3.4/site-packages/pytest_xdist-1.14.dist-info
drwxr-xr-x   3 root root 4.0K 2016-04-10 01:19 xdist/
$ py.test --version
This is pytest version 2.8.7, imported from /usr/lib64/python3.4/site-packages/pytest.py
setuptools registered plugins:
  pytest-xdist-1.14 at /usr/lib64/python3.4/site-packages/xdist/looponfail.py
  pytest-xdist-1.14 at /usr/lib64/python3.4/site-packages/xdist/plugin.py
  pytest-xdist-1.14 at /usr/lib64/python3.4/site-packages/xdist/boxed.py

---

因此，不清楚的地方被弄清楚了，错误被调试了，缓慢的测试很快并行化了。

我遇到了这个问题，并发现这是因为一个非常旧的

setuptools

（Centos6.7上提供的默认版本）

因此，首先升级

setuptools

sudo pip install --upgrade setuptools

然后重新安装

pytest

和

pytest xdist

sudo pip install --upgrade pytest pytest-xdist --force-reinstall

---

在此之后，

pytest

能够发现

xdist

插件。

我已经在我的问题中添加了“py.test--version”输出。看起来您正在安装和运行的环境有问题。可能是

sudo pip install --upgrade setuptools

sudo pip install --upgrade pytest pytest-xdist --force-reinstall