[TIP] coverage.py and os.fork()?

[Joe Malicki]

Does anyone have a recipe of getting coverage.py to work across a fork()?

I was trying to use coverage 3.3.1 with python 2.6 and
multiprocessing, and couldn't figure out how to get it to trace the
child.
Attached is a simple test program to illustrate behavior and show
things I tried.

Is there another way of doing this I didn't come across, or is this
something that needs to be hacked into coverage?

Thanks!
Joe

with coverage run -p testcover.py, i see:

jmalicki at boott-spur:~$ coverage combine
jmalicki at boott-spur:~$ coverage report -m
Name        Stmts   Exec  Cover   Missing
-----------------------------------------
testcover      19     10    52%   10-20, 27

When I explicitly call stop: coverage run -p testcover.py -t
Child!
Traceback (most recent call last):
  File "testcover.py", line 32, in <module>
    main(sys.argv)
  File "testcover.py", line 27, in main
    child(args)
  File "testcover.py", line 18, in child
    coverage.stop()
  File "/usr/local/lib/python2.6/dist-packages/coverage-3.3.1-py2.6-linux-x86_64.egg/coverage/__init__.py",
line 39, in wrapper
    return getattr(_the_coverage, name)(*args, **kwargs)
  File "/usr/local/lib/python2.6/dist-packages/coverage-3.3.1-py2.6-linux-x86_64.egg/coverage/control.py",
line 212, in stop
    self.collector.stop()
  File "/usr/local/lib/python2.6/dist-packages/coverage-3.3.1-py2.6-linux-x86_64.egg/coverage/collector.py",
line 214, in stop
    assert self._collectors[-1] is self
AssertionError

coverage run -p testcover.py -s
Child!
jmalicki at boott-spur:~$ coverage combine
coverage report -m:
Name        Stmts   Exec  Cover   Missing
-----------------------------------------
testcover      19     10    52%   10-20, 27
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