tests/test-check-help.t

setup: fix installing in a mingw environment

The addition, in 9a4adc76c88a, of a hack for the MSVC compiler class was
overwriting the original class for the Mingw32CCompiler class, leading to an
error when the HackedMingw32CCompiler is instantiated.

Differential Revision: https://phab.mercurial-scm.org/D329

#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(r':hg:`help ([a-z0-9\-.]+)`')
  > for fname in sys.argv:
  >     with open(fname) 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