Changes

2.1.16 - 2017-03-17

Fix bug in test script where temporary directories were not being removed (@sjkingo)
#35: Don't pass unsupported argument to old versions of pip (@sjkingo)
Always call pip through the Python interpreter to avoid a too-long shebang error (@sjkingo)
#26: Fix incorrect subclassing of base test class that was causing extreme test durations (@sjkingo)

2.1.15 - 2017-03-17

#34: Add support for pip -r requirements files (@jzafran and @sjkingo)

2.1.14 - 2017-02-22

#33: Add support for system-site-packages option (@evansde77)

2.1.13 - 2016-10-26

#31: Workaround to prevent shebang length errors when calling pip (@rmb938)

2.1.12 - 2016-10-22

#29: Fix AttributeError when raising OSError from inside environment (@rmb938)

2.1.11 - 2016-07-14

#28: Add support for locating pip on win32 (@eoghancunneen)

2.1.10 - 2016-06-03

#27: Support installing an editable package (-e) (@sjkingo)

2.1.9 - 2016-05-01

Move version number to library instead of setup.py (@sjkingo)
Support Python 3.5 (@sjkingo)
#24: Fixed failing test suite by adding missing dependency (@mcyprian)

2.1.8 - 2016-04-01

#21: Converted README.md to an rST document to remove dependency on setuptools-markdown (@sjkingo)

2.1.7 - 2015-08-10

Added upgrade_all() function to upgrade all packages in an environment (@sjkingo)
Added readonly argument to constructing environment that can be used to prevent operations that could potentially modify the environment (@sjkingo)
Added support for passing ~ to construct environment (e.g. ~user/venv) (@sjkingo)

2.1.6 - 2015-06-10

Version bump for broken PyPi release (@sjkingo) (no new changes to code)

2.1.5 - 2015-06-10

Improved search function that will return more accurate results. This includes a breaking change where the package list returned by env.search() is now a dictionary. (@sjkingo)
Prevent pip from checking for new version of itself and polluting the output of some commands (@sjkingo)

2.1.4 - 2015-06-04

Support for creating a wheel of packages (@rmb938)

2.1.3 - 2015-03-28

Support changing the interpreter path (@jlafon)
Improve Unicode support in pip search that broke tests (@jlafon)

2.1.2 - 2014-11-25

Added test builds through Travis CI (@sjkingo)
Fixed default options bug introduced in 2.0.1 (@ColMcp, @sposs)
Updated example.py (@sjkingo)
Fix typo in logging (@yannik-ammann)

2.1.1 - 2014-11-19

Fix typo that broke from 2.1.0 release (@sjkingo)

2.1.0 - 2014-11-19

Python 3 support (@r1s)
Unit tests for base functionality (@r1s)
Better Unicode handling (@r1s)
Tuple support for specifying package versions (@philippeowagner)

2.0.1 - 2014-11-14

Support passing command line options directly to pip (@sposs)
Misc. PEP8 fixes (@sposs)

2.0.0 - 2014-04-09

Added pip search functionality
Re-worked underlying pip processing and error handling

1.0.0 - 2013-03-27

Initial release with basic install/uninstall