tests/test-check-help.t

revset: add optimization for heads(commonancestors())

Previously, the only way to get these commits were (tested on
mozilla-central):

hg perfrevset 'heads(::a7cf55 and ::d8b15)'
! wall 4.988366 comb 4.960000 user 4.780000 sys 0.180000 (best of 3)

After this patch:

(python)
hg perfrevset 'heads(commonancestors(a7cf55 + d8b15))'
! wall 0.002155 comb 0.000000 user 0.000000 sys 0.000000 (best of 1107)

(C)
hg perfrevset 'heads(commonancestors(a7cf55 + d8b15))'
! wall 0.000568 comb 0.000000 user 0.000000 sys 0.000000 (best of 4646)

#require test-repo

  $ . "$TESTDIR/helpers-testrepo.sh"

  $ cat <<'EOF' > scanhelptopics.py
  > from __future__ import absolute_import, print_function
  > import re
  > import sys
  > if sys.platform == "win32":
  >     import os, msvcrt
  >     msvcrt.setmode(sys.stdout.fileno(), os.O_BINARY)
  > topics = set()
  > topicre = re.compile(br':hg:`help ([a-z0-9\-.]+)`')
  > for fname in sys.argv:
  >     with open(fname, 'rb') as f:
  >         topics.update(m.group(1) for m in topicre.finditer(f.read()))
  > for s in sorted(topics):
  >     print(s)
  > EOF

  $ cd "$TESTDIR"/..

Check if ":hg:`help TOPIC`" is valid:
(use "xargs -n1 -t" to see which help commands are executed)

  $ testrepohg files 'glob:{hgdemandimport,hgext,mercurial}/**/*.py' \
  > | sed 's|\\|/|g' \
  > | xargs $PYTHON "$TESTTMP/scanhelptopics.py" \
  > | xargs -n1 hg help > /dev/null