Add options for specifying python cache dirs.
Review Request #2320 - Created June 3, 2015 and submitted
Specifically, the 'egg' cache, where third party eggs are downloaded, and the 'artifact' cache. It can be useful to put these outside of the default pants workdir to circumvent 'pants clean-all' blowing them away. In a repo with many external python deps, killing the egg cache can add minutes to the next python-related pants invocation.
CI is running here: https://travis-ci.org/pantsbuild/pants/builds/65300528
Not sure how to test this otherwise, but I built the sdist and used it
in the compass repo. I then set the following in pants.ini:
Then ran the unit tests and observed the eggs put in ~/.python.egg.cache.
It's weird that we have a thing called "egg cache" and yet that's not what we assign to self._egg_cache_root here. What's actually the distinction between "egg cache" and "artifact cache"? Let's document that distinction in python_setup.py and make the variable names conform.
Nit: remove leading space.
Shouldn't this have the interpreter identity in it, as it did before?
I have a pending change that is going to conflict with this, so to minimize my own pain, and because of the 7 hour timezone difference between where you are and where I currently am, I went ahead and patched this in and pushed it. Please close this RB with the comment "Submitted as 781fce435af9575335536ef28930686533aba4b5." Thanks for the fix!