[MERGE] Slight test suite refactorings

[Vincent Ladeuil]

>>>>> "vila" == Vincent Ladeuil <v.ladeuil+lp at free.fr> writes:

<snip/>

    martin> but I don't understand this comment in this location.

    vila> It's inside multiply_tests_from_modules, but yes it may be better
    vila> placed right at the beginning of the function. I'll do that.

<cough> It *is* at the beginning of the function, but the doc
string is quite long since it contains doc tests, so... we were
just both trapped by the diff :)

     Vincent