tests/test-phabricator.t

procutil: add a option to not fully detach background process

When writing test, it is useful to make code pretending to spawn a fully
detached process while still actually waiting for it to finish. We add the
option to `procutil.runbgcommand`, to do so. We will use this in remote-filelog
tests.

Differential Revision: https://phab.mercurial-scm.org/D7584

#require vcr
  $ cat >> $HGRCPATH <<EOF
  > [extensions]
  > phabricator = 
  > EOF
  $ hg init repo
  $ cd repo
  $ cat >> .hg/hgrc <<EOF
  > [phabricator]
  > url = https://phab.mercurial-scm.org/
  > callsign = HG
  > 
  > [auth]
  > hgphab.schemes = https
  > hgphab.prefix = phab.mercurial-scm.org
  > # When working on the extension and making phabricator interaction
  > # changes, edit this to be a real phabricator token. When done, edit
  > # it back. The VCR transcripts will be auto-sanitised to replace your real
  > # token with this value.
  > hgphab.phabtoken = cli-hahayouwish
  > EOF
  $ VCR="$TESTDIR/phabricator"