/brz/remove-bazaar

# Copyright (C) 2005 by Aaron Bentley

# This program is free software; you can redistribute it and/or modify

# it under the terms of the GNU General Public License as published by

# the Free Software Foundation; either version 2 of the License, or

# (at your option) any later version.

#

# This program is distributed in the hope that it will be useful,

# but WITHOUT ANY WARRANTY; without even the implied warranty of

# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

# GNU General Public License for more details.

#

# You should have received a copy of the GNU General Public License

# along with this program; if not, write to the Free Software

# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA

import contextlib

from .branch import Branch

from .trace import note

from .errors import NoSuchRevision, BzrCommandError

class GhostFetcher(object):

    @classmethod

    def from_cmdline(cls, other):

        this_branch = Branch.open_containing('.')[0]

        if other is None:

            other = this_branch.get_parent()

            if other is None:

                raise BzrCommandError('No branch specified and no location'

                                      ' saved.')

            else:

                note("Using saved location %s.", other)

        other_branch = Branch.open_containing(other)[0]

        return cls(this_branch, other_branch)

    def __init__(self, this_branch, other_branch):

        self.this_branch = this_branch

        self.other_branch = other_branch

    def run(self):

        lock_other = self.this_branch.base != self.other_branch.base

        with contextlib.ExitStack() as exit_stack:

            exit_stack.enter_context(self.this_branch.lock_write())

            if lock_other:

                exit_stack.enter_context(self.other_branch.lock_read())

            return self._run_locked()

    def iter_ghosts(self):

        """Find all ancestors that aren't stored in this branch."""

        seen = set()

        lines = [self.this_branch.last_revision()]

        if lines[0] is None:

            return

        while len(lines) > 0:

            new_lines = []

            for line in lines:

                if line in seen:

                    continue

                seen.add(line)

                try:

                    revision = self.this_branch.repository.get_revision(line)

                    new_lines.extend(revision.parent_ids)

                except NoSuchRevision:

                    yield line

            lines = new_lines

    def _run_locked(self):

        installed = []

        failed = []

        if self.this_branch.last_revision() is None:

            print("No revisions in branch.")

            return

        # Because iter_ghosts tests for existence after our last fetch

        # is complete, it won't falsely report an ancestor as a ghost.

        # Yay iterators!

        ghosts = self.iter_ghosts()

        for revision in ghosts:

            try:

                self.this_branch.fetch(self.other_branch, revision)

                installed.append(revision)

            except NoSuchRevision:

                failed.append(revision)

        return installed, failed