contrib/convert-repo

pager: preserve Hg's exit code (and fix Windows support) (issue3225)

This changes how the pager extension invokes the pager. Prior to this change,
the extension would fork Hg and exec the pager in the parent process. This
loses Hg exit code, and it doesn't work on Windows.

Now the pager is invoked using the subprocess library, and an atexit handler is
registered that makes Hg wait for the pager to exit before it exits itself.

Note that if you exit the pager before Hg is done running, you'll get an exit
code of 255, which is caused by Python blowing up due to a broken pipe. If you
set pager.quiet=True, you'll get the OS-level return code of 141.

#!/usr/bin/env python
#
# Wrapper script around the convert.py hgext extension
# for foreign SCM conversion to mercurial format.
#

import sys
from mercurial import ui, fancyopts
from hgext import convert

# Options extracted from the cmdtable
func, options, help = convert.cmdtable['convert']

# An ui instance
u = ui.ui()

opts = {}
args = []
try:
    args = list(fancyopts.fancyopts(sys.argv[1:], options, opts))
    args += [None]*(3 - len(args))
    src, dest, revmapfile = args
except (fancyopts.getopt.GetoptError, ValueError), inst:
    u.warn('Usage:\n%s\n' % help)
    sys.exit(-1)

convert.convert(u, src, dest, revmapfile, **opts)