> I'm -0.5 myself, though, for the reason that it complicates the startup
> process a little bit more, without looking very compelling. It smells
> disturbingly like LD_PRELOAD to me.

Antoine, do you have a suggestion for how to solve the coverage.py problem?  To re-iterate: imagine you have a large test suite, and it spawns python processes during the tests.  Mercurial, for example, is like this.  You want to measure the coverage of your test suite.  This means not do you have to invoke the main suite with "python coverage.py run tests.py" instead of "python tests.py", but all the subprocess invocations need to invoke coverage.py as well.

We are looking for ways to make this as transparent as possible to the tests themselves, just as coverage measurement is now for test suites that don't spawn python subprocesses.

http://nedbatchelder.com/code/coverage/subprocess.html describes the two current hacks people can use to invoke coverage on subprocesses.  I was hoping for a cleaner more natural solution.