mercurial/repo.py

largefiles: handle merges between normal files and largefiles (issue3084)

The largefiles extension prevents users from adding a normal file
named 'foo' if there is already a largefile with the same name.
However, there was a loop-hole: when merging, it was possible to bring
in a normal file named 'foo' while also having a '.hglf/foo' file.

This patch fixes this by extending the manifest merge to deal with
these kinds of conflicts. If there is a normal file 'foo' in the
working copy, and the other parent brings in a '.hglf/foo' file, then
the user will be prompted to keep the normal file or the largefile.
Likewise for the symmetric case where a normal file is brought in via
the second parent. The prompt looks like this:

  $ hg merge
  foo has been turned into a largefile
  use (l)argefile or keep as (n)ormal file?

After the merge, either the '.hglf/foo' file or the 'foo' file will
have been deleted. This would cause status to return output like:

  $ hg status
  M foo
  R foo

To fix this, the lfiles_repo.status method is changed so that a
removed normal file isn't shown if there is largefile with the same
name, and vice versa for largefiles.

# repo.py - repository base classes for mercurial
#
# Copyright 2005, 2006 Matt Mackall <[e-mail]>
# Copyright 2006 Vadim Gelfer <[e-mail]>
#
# This software may be used and distributed according to the terms of the
# GNU General Public License version 2 or any later version.

from i18n import _
import error

class repository(object):
    def capable(self, name):
        '''tell whether repo supports named capability.
        return False if not supported.
        if boolean capability, return True.
        if string capability, return string.'''
        if name in self.capabilities:
            return True
        name_eq = name + '='
        for cap in self.capabilities:
            if cap.startswith(name_eq):
                return cap[len(name_eq):]
        return False

    def requirecap(self, name, purpose):
        '''raise an exception if the given capability is not present'''
        if not self.capable(name):
            raise error.CapabilityError(
                _('cannot %s; remote repository does not '
                  'support the %r capability') % (purpose, name))

    def local(self):
        return False

    def cancopy(self):
        return self.local()

    def close(self):
        pass