Question

我一直试图在我的OS X机器上运行Python 3.3的内置“venv”模块。我使用Homebrew安装了Python 3.3。

根据文档，创建和切换虚拟环境的工作方式正如您所期望的那样：

$ python3 -m venv myvenv
$ source myvenv/bin/activate

我测试过这样的事情：

$ echo "YEAH = 'YEAH!'" > myvenv/lib/python3.3/site-packages/thingy.py
$ python
>>> import thingy
>>> print(thingy.YEAH)
'YEAH!'

但是当我尝试安装分发时，它根本就不会进入正确的位置。出于某种原因，它坚持尝试安装到/usr/local/lib/python3.3/site-packages/，但失败并显示以下消息：

No setuptools distribution found
running install
Checking .pth file support in /usr/local/lib/python3.3/site-packages/
/Users/victor/myvenv/bin/python -E -c pass
TEST FAILED: /usr/local/lib/python3.3/site-packages/ does NOT support .pth files
error: bad install directory or PYTHONPATH

You are attempting to install a package to a directory that is not
on PYTHONPATH and which Python does not read ".pth" files from.  The
installation directory you specified (via --install-dir, --prefix, or
the distutils default setting) was:

    /usr/local/lib/python3.3/site-packages/

and your PYTHONPATH environment variable currently contains:

    ''

无论我是尝试使用distribute_setup.py安装还是直接使用源代码分发，都会发生这种情况。我甚至尝试使用--prefix=/Users/victor/myenv，但它仍然试图将所有内容都放在我的“全局”网站包中。

我无法弄清楚为什么会发生这种情况，但它在我的两台机器上都是一致的。请注意sys.prefix报告正确的路径（虚拟环境）。

这是Homebrew的问题吗？ OS X？ Python 3.3？ VENV？我吗？

Answer 1

这是Homebrew的一个问题，是的，但是自https://github.com/mxcl/homebrew/commit/0b50110107ea2998e65011ec31ce45931b446dab以来它一直在运作。

$ brew update
$ brew rm python3  #if you have installed it before
$ brew install python3
$ cd /tmp
$ which python3
  /usr/local/bin/python3
$ python3 -m venv myvenv 
$ source myvenv/bin/activate
$ wget http://python-distribute.org/distribute_setup.py  # may need brew install wget
$ python3 distribute_setup.py  
  ...
  Finished processing dependencies for distribute==0.6.45
  After install bootstrap.
  Creating /private/tmp/myvenv/lib/python3.3/site-packages/setuptools-0.6c11-py3.3.egg-info
  Creating /private/tmp/myvenv/lib/python3.3/site-packages/setuptools.pth

您看到将安装成功分发到/ tmp目录。

Answer 2

这是因为homebrew安装了distutils配置文件：

$ brew cat python3  | grep "Tell distutils" -A5
    # Tell distutils-based installers where to put scripts
    (prefix/"Frameworks/Python.framework/Versions/#{VER}/lib/python#{VER}/distutils/distutils.cfg").write <<-EOF.undent
      [install]
      install-scripts=#{scripts_folder}
      install-lib=#{site_packages}
    EOF

$ mv ~/.local/Frameworks/Python.framework/Versions/3.3/lib/python3.3/distutils/distutils.cfg ~/tmp/
$ cat ~/tmp/distutils.cfg 
[install]
install-scripts=/Users/gatto/.local/share/python3
install-lib=/Users/gatto/.local/lib/python3.3/site-packages
$ . venv/bin/activate
(venv) $ python distribute-0.6.36/distribute_setup.py
(venv) $ ls venv/lib/python3.3/site-packages/
distribute-0.6.36-py3.3.egg  easy-install.pth  setuptools-0.6c11-py3.3.egg-info  setuptools.pth

请参阅bugs.python.org上的“distutils.cfg Can Break venv”问题。

安装在Python 3.3 venv中分发（OS X / Homebrew）

2 个答案: