Log message:
Update to 1.10:

1.10 (2013-07-23)
~~~~~~~~~~~~~~~~~

* **BACKWARDS INCOMPATIBLE** Dropped support for Python 2.5. The minimum
  supported Python version is now Python 2.6.

* **BACKWARDS INCOMPATIBLE** Using ``virtualenv.py`` as an isolated script
  (i.e. without an associated ``virtualenv_support`` directory) is no longer
  supported for security reasons and will fail with an error.

  Along with this, ``--never-download`` is now always pinned to ``True``, and
  is only being maintained in the short term for backward compatibility
  (Pull #412).

* **IMPORTANT** Switched to the new setuptools (v0.9.7) which has been merged
  with Distribute_ again and works for Python 2 and 3 with one codebase.
  The ``--distribute`` and ``--setuptools`` options are now no-op.

* Updated to pip 1.4.

* Added support for PyPy3k

* Added the option to use a version number with the ``-p`` option to get the
  system copy of that Python version (Windows only)

* Removed embedded ``ez_setup.py``, ``distribute_setup.py`` and
  ``distribute_from_egg.py`` files as part of switching to merged setuptools.

* Fixed ``--relocatable`` to work better on Windows.

* Fixed issue with readline on Windows.

.. _Distribute: https://pypi.python.org/pypi/distribute

Log message:
Update to 1.9.1:

1.9.1 (2013-03-08)
~~~~~~~~~~~~~~~~~~

* Updated to pip 1.3.1 that fixed a major backward incompatible change of
  parsing URLs to externally hosted packages that got accidentily included
  in pip 1.3.

1.9 (2013-03-07)
~~~~~~~~~~~~~~~~

* Unset VIRTUAL_ENV environment variable in deactivate.bat (Pull #364)
* Upgraded distribute to 0.6.34.
* Added ``--no-setuptools`` and ``--no-pip`` options (Pull #336).
* Fixed Issue #373. virtualenv-1.8.4 was failing in cygwin (Pull #382).
* Fixed Issue #378. virtualenv is now "multiarch" aware on \ 
debian/ubuntu (Pull #379).
* Fixed issue with readline module path on pypy and OSX (Pull #374).
* Made 64bit detection compatible with Python 2.5 (Pull #393).

Log message:
Update to 1.8.4:

1.8.4 (2012-11-25)

    Updated distribute to 0.6.31. This fixes #359 (numpy install regression) on \ 
UTF-8 platforms, and provides a workaround on other platforms: \ 
PYTHONIOENCODING=utf8 pip install numpy.
    When installing virtualenv via curl, don't forget to filter out arguments \ 
the distribute setup script won't understand. Fixes #358.
    Added some more integration tests.

1.8.3 (2012-11-21)

    Fixed readline on OS X. Thanks minrk
    Updated distribute to 0.6.30 (improves our error reporting, plus new \ 
distribute features and fixes). Thanks Gabriel (g2p)
    Added compatibility with multiarch Python (Python 3.3 for example). Added an \ 
integration test. Thanks Gabriel (g2p)
    Added ability to install distribute from a user-provided egg, rather than \ 
the bundled sdist, for better speed. Thanks Paul Moore.
    Make the creation of lib64 symlink smarter about already-existing symlink, \ 
and more explicit about full paths. Fixes #334 and #330. Thanks Jeremy Orem.
    Give lib64 site-dir preference over lib on 64-bit systems, to avoid wrong \ 
32-bit compiles in the venv. Fixes #328. Thanks Damien Nozay.
    Fix a bug with prompt-handling in activate.csh in non-interactive csh \ 
shells. Fixes #332. Thanks Benjamin Root for report and patch.
    Make it possible to create a virtualenv from within a Python 3.3. pyvenv. \ 
Thanks Chris McDonough for the report.
    Add optional --setuptools option to be able to switch to it in case \ 
distribute is the default (like in Debian).

Log message:
Drop superfluous PKG_DESTDIR_SUPPORT, "user-destdir" is default these days.

Log message:
Import py-virtualenv-1.8.2 as devel/py-virtualenv.

virtualenv is a tool to create isolated Python environments.

The basic problem being addressed is one of dependencies and
versions, and indirectly permissions. Imagine you have an application
that needs version 1 of LibFoo, but another application requires
version 2. How can you use both these applications? If you install
everything into /usr/lib/python2.7/site-packages (or whatever your
platform's standard location is), it's easy to end up in a situation
where you unintentionally upgrade an application that shouldn't be
upgraded.

Or more generally, what if you want to install an application and
leave it be? If an application works, any change in its libraries
or the versions of those libraries can break the application.

Also, what if you can't install packages into the global site-packages
directory? For instance, on a shared host.

In all these cases, virtualenv can help you. It creates an environment
that has its own installation directories, that doesn't share
libraries with other virtualenv environments (and optionally doesn't
access the globally installed libraries either).