Use pytest_load_initial_conftests for startup

[schlamar]

See https://mail.python.org/pipermail/pytest-dev/2014-April/002494.html and https://bitbucket.org/memedough/pytest-cov/issue/12/doesnt-capture-coverage-on-imports-made

[lahwran]

I need this and am starting on it. will pull request

[lahwran]

it seems that pytest_addoption arguments aren't available yet in load_initial_conftests. or something. not sure, because _pytest.capture seems to make use of them, but if I just change pytest_configure to pytest_load_initial_conftests in pytest-cov (and fiddle the arguments), early_config.getoption("cov_source") is empty. despite that I definitely passed it on the cli.

???

pytest you confusing beast...

doh. it's because it that was recently added, in pytest commit 083d8d0b. I'll do a slightly hacky thing for older versions of py.test.

[lahwran]

xdist integration is a royal pain. I think xdist is going to have to be modified to make this work, because I don't see any way to know we're in a slave process...

[schlamar]

Exactly the issue I have experienced: https://travis-ci.org/schlamar/pytest-cov/builds/23274310

[lahwran]

I give up on xdist. I'm just going to make it revert to the old way of doing things if xdist is in use, and put a big comment in explaining what's going on and when it can be fixed.

I carefully thumbed through the xdist code, and the only way to solve it would be soooo incredibly hacky (jam something into args). not going to go there. need to fix xdist to do that properly.

[schlamar]

#4