/brz/remove-bazaar

# Copyright (C) 2008, 2009, 2010 Canonical Ltd

#

# 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

from __future__ import absolute_import

import errno

import re

from . import errors

from .lazy_import import lazy_import

lazy_import(globals(), """

from breezy import (

    bencode,

    merge,

    merge3,

    transform,

)

from breezy.bzr import (

    pack,

    )

""")

class ShelfCorrupt(errors.BzrError):

    _fmt = "Shelf corrupt."

class NoSuchShelfId(errors.BzrError):

    _fmt = 'No changes are shelved with id "%(shelf_id)d".'

    def __init__(self, shelf_id):

        errors.BzrError.__init__(self, shelf_id=shelf_id)

class InvalidShelfId(errors.BzrError):

    _fmt = '"%(invalid_id)s" is not a valid shelf id, try a number instead.'

    def __init__(self, invalid_id):

        errors.BzrError.__init__(self, invalid_id=invalid_id)

class ShelfCreator(object):

    """Create a transform to shelve objects and its inverse."""

    def __init__(self, work_tree, target_tree, file_list=None):

        """Constructor.

        :param work_tree: The working tree to apply changes to. This is not

            required to be locked - a tree_write lock will be taken out.

        :param target_tree: The tree to make the working tree more similar to.

            This is not required to be locked - a read_lock will be taken out.

        :param file_list: The files to make more similar to the target.

        """

        self.work_tree = work_tree

        self.work_transform = transform.TreeTransform(work_tree)

        try:

            self.target_tree = target_tree

            self.shelf_transform = transform.TransformPreview(self.target_tree)

            try:

                self.renames = {}

                self.creation = {}

                self.deletion = {}

                self.iter_changes = work_tree.iter_changes(

                    self.target_tree, specific_files=file_list)

            except:

                self.shelf_transform.finalize()

                raise

        except:

            self.work_transform.finalize()

            raise

    def iter_shelvable(self):

        """Iterable of tuples describing shelvable changes.

        As well as generating the tuples, this updates several members.

        Tuples may be::

           ('add file', file_id, work_kind, work_path)

           ('delete file', file_id, target_kind, target_path)

           ('rename', file_id, target_path, work_path)

           ('change kind', file_id, target_kind, work_kind, target_path)

           ('modify text', file_id)

           ('modify target', file_id, target_target, work_target)

        """

        for (file_id, paths, changed, versioned, parents, names, kind,

             executable) in self.iter_changes:

            # don't shelve add of tree root.  Working tree should never

            # lack roots, and bzr misbehaves when they do.

            # FIXME ADHB (2009-08-09): should still shelve adds of tree roots

            # when a tree root was deleted / renamed.

            if kind[0] is None and names[1] == '':

                continue

            # Also don't shelve deletion of tree root.

            if kind[1] is None and names[0] == '':

                continue

            if kind[0] is None or versioned[0] is False:

                self.creation[file_id] = (kind[1], names[1], parents[1],

                                          versioned)

                yield ('add file', file_id, kind[1], paths[1])

            elif kind[1] is None or versioned[0] is False:

                self.deletion[file_id] = (kind[0], names[0], parents[0],

                                          versioned)

                yield ('delete file', file_id, kind[0], paths[0])

            else:

                if names[0] != names[1] or parents[0] != parents[1]:

                    self.renames[file_id] = (names, parents)

                    yield ('rename', file_id) + paths

                if kind[0] != kind[1]:

                    yield ('change kind', file_id, kind[0], kind[1], paths[0])

                elif kind[0] == 'symlink':

                    t_target = self.target_tree.get_symlink_target(paths[0])

                    w_target = self.work_tree.get_symlink_target(paths[1])

                    yield ('modify target', file_id, paths[0], t_target,

                           w_target)

                elif changed:

                    yield ('modify text', file_id)

    def shelve_change(self, change):

        """Shelve a change in the iter_shelvable format."""

        if change[0] == 'rename':

            self.shelve_rename(change[1])

        elif change[0] == 'delete file':

            self.shelve_deletion(change[1])

        elif change[0] == 'add file':

            self.shelve_creation(change[1])

        elif change[0] in ('change kind', 'modify text'):

            self.shelve_content_change(change[1])

        elif change[0] == 'modify target':

            self.shelve_modify_target(change[1])

        else:

            raise ValueError('Unknown change kind: "%s"' % change[0])

    def shelve_all(self):

        """Shelve all changes.

        :return: ``True`` if changes were shelved, otherwise ``False``.

        """

        change = None

        for change in self.iter_shelvable():

            self.shelve_change(change)

        return change is not None

    def shelve_rename(self, file_id):

        """Shelve a file rename.

        :param file_id: The file id of the file to shelve the renaming of.

        """

        names, parents = self.renames[file_id]

        w_trans_id = self.work_transform.trans_id_file_id(file_id)

        work_parent = self.work_transform.trans_id_file_id(parents[0])

        self.work_transform.adjust_path(names[0], work_parent, w_trans_id)

        s_trans_id = self.shelf_transform.trans_id_file_id(file_id)

        shelf_parent = self.shelf_transform.trans_id_file_id(parents[1])

        self.shelf_transform.adjust_path(names[1], shelf_parent, s_trans_id)

    def shelve_modify_target(self, file_id):

        """Shelve a change of symlink target.

        :param file_id: The file id of the symlink which changed target.

        :param new_target: The target that the symlink should have due

            to shelving.

        """

        new_path = self.target_tree.id2path(file_id)

        new_target = self.target_tree.get_symlink_target(new_path)

        w_trans_id = self.work_transform.trans_id_file_id(file_id)

        self.work_transform.delete_contents(w_trans_id)

        self.work_transform.create_symlink(new_target, w_trans_id)

        old_path = self.work_tree.id2path(file_id)

        old_target = self.work_tree.get_symlink_target(old_path)

        s_trans_id = self.shelf_transform.trans_id_file_id(file_id)

        self.shelf_transform.delete_contents(s_trans_id)

        self.shelf_transform.create_symlink(old_target, s_trans_id)

    def shelve_lines(self, file_id, new_lines):

        """Shelve text changes to a file, using provided lines.

        :param file_id: The file id of the file to shelve the text of.

        :param new_lines: The lines that the file should have due to shelving.

        """

        w_trans_id = self.work_transform.trans_id_file_id(file_id)

        self.work_transform.delete_contents(w_trans_id)

        self.work_transform.create_file(new_lines, w_trans_id)

        s_trans_id = self.shelf_transform.trans_id_file_id(file_id)

        self.shelf_transform.delete_contents(s_trans_id)

        inverse_lines = self._inverse_lines(new_lines, file_id)

        self.shelf_transform.create_file(inverse_lines, s_trans_id)

    @staticmethod

    def _content_from_tree(tt, tree, file_id):

        trans_id = tt.trans_id_file_id(file_id)

        tt.delete_contents(trans_id)

        transform.create_from_tree(tt, trans_id, tree, tree.id2path(file_id),

                                   file_id)

    def shelve_content_change(self, file_id):

        """Shelve a kind change or binary file content change.

        :param file_id: The file id of the file to shelve the content change

            of.

        """

        self._content_from_tree(self.work_transform, self.target_tree, file_id)

        self._content_from_tree(self.shelf_transform, self.work_tree, file_id)

    def shelve_creation(self, file_id):

        """Shelve creation of a file.

        This handles content and inventory id.

        :param file_id: The file_id of the file to shelve creation of.

        """

        kind, name, parent, versioned = self.creation[file_id]

        version = not versioned[0]

        self._shelve_creation(self.work_tree, file_id, self.work_transform,

                              self.shelf_transform, kind, name, parent,

                              version)

    def shelve_deletion(self, file_id):

        """Shelve deletion of a file.

        This handles content and inventory id.

        :param file_id: The file_id of the file to shelve deletion of.

        """

        kind, name, parent, versioned = self.deletion[file_id]

        existing_path = self.target_tree.id2path(file_id)

        if not self.work_tree.has_filename(existing_path):

            existing_path = None

        version = not versioned[1]

        self._shelve_creation(self.target_tree, file_id, self.shelf_transform,

                              self.work_transform, kind, name, parent,

                              version, existing_path=existing_path)

    def _shelve_creation(self, tree, file_id, from_transform, to_transform,

                         kind, name, parent, version, existing_path=None):

        w_trans_id = from_transform.trans_id_file_id(file_id)

        if parent is not None and kind is not None:

            from_transform.delete_contents(w_trans_id)

        from_transform.unversion_file(w_trans_id)

        if existing_path is not None:

            s_trans_id = to_transform.trans_id_tree_path(existing_path)

        else:

            s_trans_id = to_transform.trans_id_file_id(file_id)

        if parent is not None:

            s_parent_id = to_transform.trans_id_file_id(parent)

            to_transform.adjust_path(name, s_parent_id, s_trans_id)

            if existing_path is None:

                if kind is None:

                    to_transform.create_file([b''], s_trans_id)

                else:

                    transform.create_from_tree(

                        to_transform, s_trans_id, tree,

                        tree.id2path(file_id), file_id)

        if version:

            to_transform.version_file(file_id, s_trans_id)

    def _inverse_lines(self, new_lines, file_id):

        """Produce a version with only those changes removed from new_lines."""

        target_path = self.target_tree.id2path(file_id)

        target_lines = self.target_tree.get_file_lines(target_path)

        work_path = self.work_tree.id2path(file_id)

        work_lines = self.work_tree.get_file_lines(work_path)

        return merge3.Merge3(new_lines, target_lines, work_lines).merge_lines()

    def finalize(self):

        """Release all resources used by this ShelfCreator."""

        self.work_transform.finalize()

        self.shelf_transform.finalize()

    def transform(self):

        """Shelve changes from working tree."""

        self.work_transform.apply()

    @staticmethod

    def metadata_record(serializer, revision_id, message=None):

        metadata = {b'revision_id': revision_id}

        if message is not None:

            metadata[b'message'] = message.encode('utf-8')

        return serializer.bytes_record(

            bencode.bencode(metadata), ((b'metadata',),))

    def write_shelf(self, shelf_file, message=None):

        """Serialize the shelved changes to a file.

        :param shelf_file: A file-like object to write the shelf to.

        :param message: An optional message describing the shelved changes.

        :return: the filename of the written file.

        """

        transform.resolve_conflicts(self.shelf_transform)

        revision_id = self.target_tree.get_revision_id()

        return self._write_shelf(shelf_file, self.shelf_transform, revision_id,

                                 message)

    @classmethod

    def _write_shelf(cls, shelf_file, transform, revision_id, message=None):

        serializer = pack.ContainerSerialiser()

        shelf_file.write(serializer.begin())

        metadata = cls.metadata_record(serializer, revision_id, message)

        shelf_file.write(metadata)

        for bytes in transform.serialize(serializer):

            shelf_file.write(bytes)

        shelf_file.write(serializer.end())

class Unshelver(object):

    """Unshelve shelved changes."""

    def __init__(self, tree, base_tree, transform, message):

        """Constructor.

        :param tree: The tree to apply the changes to.

        :param base_tree: The basis to apply the tranform to.

        :param message: A message from the shelved transform.

        """

        self.tree = tree

        self.base_tree = base_tree

        self.transform = transform

        self.message = message

    @staticmethod

    def iter_records(shelf_file):

        parser = pack.ContainerPushParser()

        parser.accept_bytes(shelf_file.read())

        return iter(parser.read_pending_records())

    @staticmethod

    def parse_metadata(records):

        names, metadata_bytes = next(records)

        if names[0] != (b'metadata',):

            raise ShelfCorrupt

        metadata = bencode.bdecode(metadata_bytes)

        message = metadata.get(b'message')

        if message is not None:

            metadata[b'message'] = message.decode('utf-8')

        return metadata

    @classmethod

    def from_tree_and_shelf(klass, tree, shelf_file):

        """Create an Unshelver from a tree and a shelf file.

        :param tree: The tree to apply shelved changes to.

        :param shelf_file: A file-like object containing shelved changes.

        :return: The Unshelver.

        """

        records = klass.iter_records(shelf_file)

        metadata = klass.parse_metadata(records)

        base_revision_id = metadata[b'revision_id']

        try:

            base_tree = tree.revision_tree(base_revision_id)

        except errors.NoSuchRevisionInTree:

            base_tree = tree.branch.repository.revision_tree(base_revision_id)

        tt = transform.TransformPreview(base_tree)

        tt.deserialize(records)

        return klass(tree, base_tree, tt, metadata.get(b'message'))

    def make_merger(self):

        """Return a merger that can unshelve the changes."""

        target_tree = self.transform.get_preview_tree()

        merger = merge.Merger.from_uncommitted(self.tree, target_tree,

                                               self.base_tree)

        merger.merge_type = merge.Merge3Merger

        return merger

    def finalize(self):

        """Release all resources held by this Unshelver."""

        self.transform.finalize()

class ShelfManager(object):

    """Maintain a list of shelved changes."""

    def __init__(self, tree, transport):

        self.tree = tree

        self.transport = transport.clone('shelf')

        self.transport.ensure_base()

    def get_shelf_filename(self, shelf_id):

        return 'shelf-%d' % shelf_id

    def get_shelf_ids(self, filenames):

        matcher = re.compile('shelf-([1-9][0-9]*)')

        shelf_ids = []

        for filename in filenames:

            match = matcher.match(filename)

            if match is not None:

                shelf_ids.append(int(match.group(1)))

        return shelf_ids

    def new_shelf(self):

        """Return a file object and id for a new set of shelved changes."""

        last_shelf = self.last_shelf()

        if last_shelf is None:

            next_shelf = 1

        else:

            next_shelf = last_shelf + 1

        filename = self.get_shelf_filename(next_shelf)

        shelf_file = open(self.transport.local_abspath(filename), 'wb')

        return next_shelf, shelf_file

    def shelve_changes(self, creator, message=None):

        """Store the changes in a ShelfCreator on a shelf."""

        next_shelf, shelf_file = self.new_shelf()

        try:

            creator.write_shelf(shelf_file, message)

        finally:

            shelf_file.close()

        creator.transform()

        return next_shelf

    def read_shelf(self, shelf_id):

        """Return the file associated with a shelf_id for reading.

        :param shelf_id: The id of the shelf to retrive the file for.

        """

        filename = self.get_shelf_filename(shelf_id)

        try:

            return open(self.transport.local_abspath(filename), 'rb')

        except IOError as e:

            if e.errno != errno.ENOENT:

                raise

            raise NoSuchShelfId(shelf_id)

    def get_unshelver(self, shelf_id):

        """Return an unshelver for a given shelf_id.

        :param shelf_id: The shelf id to return the unshelver for.

        """

        shelf_file = self.read_shelf(shelf_id)

        try:

            return Unshelver.from_tree_and_shelf(self.tree, shelf_file)

        finally:

            shelf_file.close()

    def get_metadata(self, shelf_id):

        """Return the metadata associated with a given shelf_id."""

        shelf_file = self.read_shelf(shelf_id)

        try:

            records = Unshelver.iter_records(shelf_file)

        finally:

            shelf_file.close()

        return Unshelver.parse_metadata(records)

    def delete_shelf(self, shelf_id):

        """Delete the shelved changes for a given id.

        :param shelf_id: id of the shelved changes to delete.

        """

        filename = self.get_shelf_filename(shelf_id)

        self.transport.delete(filename)

    def active_shelves(self):

        """Return a list of shelved changes."""

        active = sorted(self.get_shelf_ids(self.transport.list_dir('.')))

        return active

    def last_shelf(self):

        """Return the id of the last-created shelved change."""

        active = self.active_shelves()

        if len(active) > 0:

            return active[-1]

        else:

            return None