/brz/remove-bazaar

# Copyright (C) 2007, 2009-2012 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

# Original author: David Allouche

from . import (

    errors,

    lock,

    merge,

    revision

    )

from .branch import Branch

from .i18n import gettext

from .trace import note

def _run_post_switch_hooks(control_dir, to_branch, force, revision_id):

    from .branch import SwitchHookParams

    hooks = Branch.hooks['post_switch']

    if not hooks:

        return

    params = SwitchHookParams(control_dir, to_branch, force, revision_id)

    for hook in hooks:

        hook(params)

def switch(control_dir, to_branch, force=False, quiet=False, revision_id=None,

           store_uncommitted=False, possible_transports=None):

    """Switch the branch associated with a checkout.

    :param control_dir: ControlDir of the checkout to change

    :param to_branch: branch that the checkout is to reference

    :param force: skip the check for local commits in a heavy checkout

    :param revision_id: revision ID to switch to.

    :param store_uncommitted: If True, store uncommitted changes in the

        branch.

    """

    try:

        tree = control_dir.open_workingtree()

    except errors.NotBranchError as ex:

        # Lightweight checkout and branch is no longer there

        if not force or store_uncommitted:

            raise ex

        else:

            tree = None

    else:

        if store_uncommitted or tree.branch.get_bound_location():

            tree.lock_write()

        else:

            tree.lock_tree_write()

    try:

        if tree is not None:

            parent_ids = tree.get_parent_ids()

            if len(parent_ids) > 1:

                raise errors.BzrCommandError(

                    gettext('Pending merges must be '

                            'committed or reverted before using switch.'))

        if store_uncommitted:

            tree.store_uncommitted()

        if tree is None:

            source_repository = to_branch.repository

            base_revision_id = None

        else:

            source_repository = tree.branch.repository

            # Attempt to retrieve the base_revision_id now, since some

            # working tree formats (i.e. git) don't have their own

            # last_revision but just use that of the currently active branch.

            base_revision_id = tree.last_revision()

    finally:

        if tree is not None:

            tree.unlock()

    with to_branch.lock_read():

        _set_branch_location(control_dir, to_branch, tree.branch if tree else None, force)

    tree = control_dir.open_workingtree()

    if store_uncommitted:

        tree.lock_write()

    else:

        tree.lock_tree_write()

    try:

        if base_revision_id is None:

            # If we couldn't get to the tree's last_revision earlier, perhaps

            # we can now.

            base_revision_id = tree.last_revision()

        if revision_id is None:

            revision_id = to_branch.last_revision()

        if base_revision_id == revision_id:

            if not quiet:

                note(gettext("Tree is up to date at revision %d."),

                     to_branch.revno())

        else:

            base_tree = source_repository.revision_tree(base_revision_id)

            target_tree = to_branch.repository.revision_tree(revision_id)

            merge.Merge3Merger(tree, tree, base_tree, target_tree)

            tree.set_last_revision(revision_id)

            if not quiet:

                note(gettext('Updated to revision %d.') % to_branch.revno())

        if store_uncommitted:

            tree.restore_uncommitted()

        _run_post_switch_hooks(control_dir, to_branch, force, revision_id)

    finally:

        tree.unlock()

def _set_branch_location(control, to_branch, current_branch, force=False):

    """Set location value of a branch reference.

    :param control: ControlDir of the checkout to change

    :param to_branch: branch that the checkout is to reference

    :param force: skip the check for local commits in a heavy checkout

    """

    branch_format = control.find_branch_format()

    if branch_format.get_reference(control) is not None:

        # Lightweight checkout: update the branch reference

        branch_format.set_reference(control, None, to_branch)

    else:

        b = current_branch

        bound_branch = b.get_bound_location()

        if bound_branch is not None:

            # Heavyweight checkout: check all local commits

            # have been pushed to the current bound branch then

            # synchronise the local branch with the new remote branch

            # and bind to it

            possible_transports = []

            try:

                if not force and _any_local_commits(b, possible_transports):

                    raise errors.BzrCommandError(gettext(

                        'Cannot switch as local commits found in the checkout. '

                        'Commit these to the bound branch or use --force to '

                        'throw them away.'))

            except errors.BoundBranchConnectionFailure as e:

                raise errors.BzrCommandError(gettext(

                    'Unable to connect to current master branch %(target)s: '

                    '%(error)s To switch anyway, use --force.') %

                    e.__dict__)

            with b.lock_write():

                b.set_bound_location(None)

                b.pull(to_branch, overwrite=True,

                       possible_transports=possible_transports)

                b.set_bound_location(to_branch.base)

                b.set_parent(b.get_master_branch().get_parent())

        else:

            # If this is a standalone tree and the new branch

            # is derived from this one, create a lightweight checkout.

            with b.lock_read():

                graph = b.repository.get_graph(to_branch.repository)

                if (b.controldir._format.colocated_branches and

                    (force or graph.is_ancestor(

                        b.last_revision(), to_branch.last_revision()))):

                    b.controldir.destroy_branch()

                    b.controldir.set_branch_reference(to_branch, name="")

                else:

                    raise errors.BzrCommandError(

                        gettext('Cannot switch a branch, only a checkout.'))

def _any_local_commits(this_branch, possible_transports):

    """Does this branch have any commits not in the master branch?"""

    last_rev = revision.ensure_null(this_branch.last_revision())

    if last_rev != revision.NULL_REVISION:

        other_branch = this_branch.get_master_branch(possible_transports)

        with this_branch.lock_read(), other_branch.lock_read():

            other_last_rev = other_branch.last_revision()

            graph = this_branch.repository.get_graph(

                other_branch.repository)

            if not graph.is_ancestor(last_rev, other_last_rev):

                return True

    return False