id	summary	reporter	owner	description	type	status	component	version	severity	resolution	keywords	cc	stage	has_patch	needs_docs	needs_tests	needs_better_patch	easy	ui_ux
25209	coverage html doesn't work as documented	Peter Schmidt	nobody	"After running the command, under OSX 10.10.4 / Python 3.4.2 (via homebrew) and coverage==3.7.1:
{{{
coverage run ./runtests.py
}}}

I get no `.coverage` file, after:
https://github.com/django/django/commit/4202959b6febd02cdaa712c666fa0d79569038ca 

This appears to be caused by the `parallel = True` option, details:
http://nedbatchelder.com/code/coverage/config.html#h_run

For instance, I currently have:
{{{
(django_py3)pzrq@icebox:~/Projects/django/tests$ ls -a | grep .coverage
.coverage.icebox.local.42652.649933
.coverage.icebox.local.42665.263961
.coverage.icebox.local.42673.382480 
...
# Importantly no .coverage file
}}}
This means when you run downstream tools, such as `coverage report -m` or `coverage html` as recommended in the Django docs, i.e. https://docs.djangoproject.com/en/1.8/internals/contributing/writing-code/unit-tests/#code-coverage, you get the not very interesting output like the following:
{{{
(django_py3)pzrq@icebox:~/Projects/django/tests$ coverage report -m
Name    Stmts   Miss  Cover   Missing
-------------------------------------
(django_py3)pzrq@icebox:~/Projects/django/tests$ 
}}}

I can see two possible fixes to discuss:

1. Remove `parallel = True` from `.coveragerc`
2. Update the documentation such as https://docs.djangoproject.com/en/dev/internals/contributing/writing-code/unit-tests/#code-coverage with the intermediate `coverage combine` step, to merge the different coverage report(s) together to generate a more typical `.coverage` file.

AFAIK multiprocessing isn't supported by the Django test runner, so +1 for option 1."	Bug	closed	Testing framework	dev	Normal	fixed		Markus Holtermann Shai Berger	Ready for checkin	0	0	0	0	0	0