contrib/simplemerge

strip: don't allow empty changegroup in bundle1

Applying an empty changegroup has been an error since the
beginning. The only exception was strip, which would allow to apply an
empty changegroup from the temporary bundle. However, the emptyok=True
option was only set for bundle1 bundles. In other words, temporary
bundle2 bundles would fail if they were empty.

Bundle2 has now been used enough that it seems safe to say that we
simply don't create bundle2 bundles with empty changegroups. That also
suggests that we never create bundle1 bundles with empty changegroups
(i.e. empty bundle1 bundles, since bundle1 is just a changegroup),
because, AFAICT, the code leading up to the application of the bundle
is the same for bundle1 and bundle2.

Therefore, let's stop passing emptyok=True, so we more clearly get the
same behavior for bundle1 and bundle2.

#!/usr/bin/env python

from mercurial import demandimport
demandimport.enable()

import getopt
import sys
from mercurial.i18n import _
from mercurial import error, simplemerge, fancyopts, util, ui

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):
        util.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'))
    sys.exit(simplemerge.simplemerge(ui.ui.load(), *args, **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)