tests/mockblackbox.py

exthelper: improve docs to indicate what module vars are needed

I recently tried creating an extension "from scratch" using exthelper, and it
wasn't obvious that you needed these. I believe that a careful reading of one of
the comments would tell you that they were required, but it's easy to miss and
having the examples be "complete" is helpful.

Differential Revision: https://phab.mercurial-scm.org/D10295

from __future__ import absolute_import
from mercurial.utils import procutil

# XXX: we should probably offer a devel option to do this in blackbox directly
def getuser():
    return b'bob'


def getpid():
    return 5000


# mock the date and user apis so the output is always the same
def uisetup(ui):
    procutil.getuser = getuser
    procutil.getpid = getpid