CONTRIBUTING doc out-of-date: how to install locally

[waprin]

CONTRIBUTING.rst is kind of confusing, specifically the part about using tox to create an environment.

Someone had problems using tox -r --notest -e py27 to "poke around", as far as I can tell skip_install is true so the environment is not actually created from the root of the repo. Maybe it meant to do so only from a specific package?

I also think since many tox files don't actually install the setup.py deps, it's confusing to suggest using tox to install things, probably better just to use pip.

[daspecster]

@waprin the reason that we're using the tox --recreate flow for development right now is because of the namespace package issue for using the --develop flag with pip.

See: pypa/setuptools#250

I've tried a couple things but the way that @dhermes has tox setup right now has been the only way to reliably develop without accidentally grabbing a cached version of the library.

Maybe I'm missing your point though?

[jcoatgoogle]

Just linking this to #2786, in which I detail a bit more of my misadventures with tox

For using pip instead, any pointers on what to do? Happy to add it to the docs

[dhermes]

@waprin That is just bit-rot in the CONTRIBUTING doc. I wrote it before I made those changes to tox -e py27,py34,py35.

What'd I'd really like to do is disable them, since the "umbrella" test runs are handled by https://github.com/GoogleCloudPlatform/google-cloud-python/blob/d775489da48d594ce5173a4078af4a0d3d2863f4/scripts/run_unit_tests.py

[jcoatgoogle]

Hm, the tox solution started failing again. I tried deleting all the .tox directories, but the issue I'm seeing is that I have a change to datastore/ which depends on a change in core/, but I'm not able to see the change in core/. It's weird because it was working...alas, I rebased in master, but I'm curious if there's a way to properly deal with that? I've checked the site-packages and the change is in fact not reflected in the new file... not sure if something changed, or if I somehow got lucky earlier?!

To unblock myself I can just manually copy the files into site-packages... is this sort of thing meant to be supported?

Thanks again

[dhermes]

@jcoatgoogle

1. Are you running tox -e py27 in the project root or in the datastore/ dir?
2. Make sure you have the latest version checked out, it sounds like you're running into a problem that's been solved for a few weeks
3. Ping me on Hangouts?