tests/helper-runtests.sh

phabricator: allow local revisions to be specified with `phabupdate`

It's way easier and less error prone to specify a revset after importing a
series than to manually type in a series of Differentials.

Unlike most revision oriented commands, this requires the `--rev` option
explicitly because the existing `DREVSPEC` doesn't need to have the leading 'D',
and therefore the meaning is ambiguous.  I wouldn't have a problem giving
precedence to the local revnum, but `phabread` and `phabimport` also use
DREVSPEC, and local revisions make no sense there.  I would be fine with
modifying that definition to require the leading 'D', but I'm not sure how many
people are used to not specifying it.

Differential Revision: https://phab.mercurial-scm.org/D9356

#
# Avoid interference from actual test env:

unset HGTEST_JOBS
unset HGTEST_TIMEOUT
unset HGTEST_PORT
unset HGTEST_SHELL