contrib/simplemerge

help: describe more detail about capabilities while deciding merge tool

"hg help merge-tools" describes as below:

    (internal merge tools) will by default not handle symlinks or
    binary files.

But in some cases, Mercurial assumes that internal merge tools have
one or both of these capabilities.

"hg help merge-tools" also describes as below, for matching patterns in
merge-patterns configuration section. But this is not sufficient.

    Here, binary capabilities of the merge tool are not considered.

This patch describes more detail about capabilities while deciding
merge tool.

#!/usr/bin/env python
from __future__ import absolute_import

import getopt
import sys

import hgdemandimport
hgdemandimport.enable()

from mercurial.i18n import _
from mercurial import (
    context,
    error,
    fancyopts,
    simplemerge,
    ui as uimod,
)
from mercurial.utils import (
    procutil,
)

options = [('L', 'label', [], _('labels to use on conflict markers')),
           ('a', 'text', None, _('treat all files as text')),
           ('p', 'print', None,
            _('print results instead of overwriting LOCAL')),
           ('', 'no-minimal', None, _('no effect (DEPRECATED)')),
           ('h', 'help', None, _('display help and exit')),
           ('q', 'quiet', None, _('suppress output'))]

usage = _('''simplemerge [OPTS] LOCAL BASE OTHER

    Simple three-way file merge utility with a minimal feature set.

    Apply to LOCAL the changes necessary to go from BASE to OTHER.

    By default, LOCAL is overwritten with the results of this operation.
''')

class ParseError(Exception):
    """Exception raised on errors in parsing the command line."""

def showhelp():
    sys.stdout.write(usage)
    sys.stdout.write('\noptions:\n')

    out_opts = []
    for shortopt, longopt, default, desc in options:
        out_opts.append(('%2s%s' % (shortopt and '-%s' % shortopt,
                                    longopt and ' --%s' % longopt),
                         '%s' % desc))
    opts_len = max([len(opt[0]) for opt in out_opts])
    for first, second in out_opts:
        sys.stdout.write(' %-*s  %s\n' % (opts_len, first, second))

try:
    for fp in (sys.stdin, sys.stdout, sys.stderr):
        procutil.setbinary(fp)

    opts = {}
    try:
        args = fancyopts.fancyopts(sys.argv[1:], options, opts)
    except getopt.GetoptError as e:
        raise ParseError(e)
    if opts['help']:
        showhelp()
        sys.exit(0)
    if len(args) != 3:
            raise ParseError(_('wrong number of arguments'))
    local, base, other = args
    sys.exit(simplemerge.simplemerge(uimod.ui.load(),
                                     context.arbitraryfilectx(local),
                                     context.arbitraryfilectx(base),
                                     context.arbitraryfilectx(other),
                                     **opts))
except ParseError as e:
    sys.stdout.write("%s: %s\n" % (sys.argv[0], e))
    showhelp()
    sys.exit(1)
except error.Abort as e:
    sys.stderr.write("abort: %s\n" % e)
    sys.exit(255)
except KeyboardInterrupt:
    sys.exit(255)