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  • Committer: Aaron Bentley
  • Date: 2012-07-23 16:47:33 UTC
  • mto: This revision was merged to the branch mainline in revision 6540.
  • Revision ID: aaron@aaronbentley.com-20120723164733-gg80rc88eh07szod
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bzrlib/switch.py
 
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# Copyright (C) 2007, 2009-2012 Canonical Ltd.
 
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#
 
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# This program is free software; you can redistribute it and/or modify
 
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# it under the terms of the GNU General Public License as published by
 
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# the Free Software Foundation; either version 2 of the License, or
 
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# (at your option) any later version.
 
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#
 
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# This program is distributed in the hope that it will be useful,
 
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# but WITHOUT ANY WARRANTY; without even the implied warranty of
 
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# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 
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# GNU General Public License for more details.
 
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#
 
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# You should have received a copy of the GNU General Public License
 
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# along with this program; if not, write to the Free Software
 
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# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
 
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from __future__ import absolute_import
 
18
 
 
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# Original author: David Allouche
 
20
 
 
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from bzrlib import (
 
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    errors,
 
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    lock,
 
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    merge,
 
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    revision
 
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    )
 
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from bzrlib.branch import Branch
 
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from bzrlib.i18n import gettext
 
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from bzrlib.trace import note
 
30
 
 
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def _run_post_switch_hooks(control_dir, to_branch, force, revision_id):
 
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    from bzrlib.branch import SwitchHookParams
 
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    hooks = Branch.hooks['post_switch']
 
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    if not hooks:
 
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        return
 
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    params = SwitchHookParams(control_dir, to_branch, force, revision_id)
 
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    for hook in hooks:
 
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        hook(params)
 
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def switch(control_dir, to_branch, force=False, quiet=False, revision_id=None,
 
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           store_uncommitted=False):
 
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    """Switch the branch associated with a checkout.
 
43
 
 
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    :param control_dir: ControlDir of the checkout to change
 
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    :param to_branch: branch that the checkout is to reference
 
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    :param force: skip the check for local commits in a heavy checkout
 
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    :param revision_id: revision ID to switch to.
 
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    :param store_uncommitted: If True, store uncommitted changes in the
 
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        branch.
 
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    """
 
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    _check_pending_merges(control_dir, force)
 
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    try:
 
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        source_repository = control_dir.open_branch().repository
 
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    except errors.NotBranchError:
 
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        source_repository = to_branch.repository
 
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    if store_uncommitted:
 
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        with lock.write_locked(control_dir.open_workingtree()) as tree:
 
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            tree.store_uncommitted()
 
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    to_branch.lock_read()
 
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    try:
 
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        _set_branch_location(control_dir, to_branch, force)
 
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    finally:
 
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        to_branch.unlock()
 
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    tree = control_dir.open_workingtree()
 
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    _update(tree, source_repository, quiet, revision_id, store_uncommitted)
 
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    _run_post_switch_hooks(control_dir, to_branch, force, revision_id)
 
67
 
 
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def _check_pending_merges(control, force=False):
 
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    """Check that there are no outstanding pending merges before switching.
 
70
 
 
71
    :param control: ControlDir of the branch to check
 
72
    """
 
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    try:
 
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        tree = control.open_workingtree()
 
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    except errors.NotBranchError, ex:
 
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        # Lightweight checkout and branch is no longer there
 
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        if force:
 
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            return
 
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        else:
 
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            raise ex
 
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    # XXX: Should the tree be locked for get_parent_ids?
 
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    existing_pending_merges = tree.get_parent_ids()[1:]
 
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    if len(existing_pending_merges) > 0:
 
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        raise errors.BzrCommandError(gettext('Pending merges must be '
 
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            'committed or reverted before using switch.'))
 
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87
 
 
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def _set_branch_location(control, to_branch, force=False):
 
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    """Set location value of a branch reference.
 
90
 
 
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    :param control: ControlDir of the checkout to change
 
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    :param to_branch: branch that the checkout is to reference
 
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    :param force: skip the check for local commits in a heavy checkout
 
94
    """
 
95
    branch_format = control.find_branch_format()
 
96
    if branch_format.get_reference(control) is not None:
 
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        # Lightweight checkout: update the branch reference
 
98
        branch_format.set_reference(control, None, to_branch)
 
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    else:
 
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        b = control.open_branch()
 
101
        bound_branch = b.get_bound_location()
 
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        if bound_branch is not None:
 
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            # Heavyweight checkout: check all local commits
 
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            # have been pushed to the current bound branch then
 
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            # synchronise the local branch with the new remote branch
 
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            # and bind to it
 
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            possible_transports = []
 
108
            try:
 
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                if not force and _any_local_commits(b, possible_transports):
 
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                    raise errors.BzrCommandError(gettext(
 
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                        'Cannot switch as local commits found in the checkout. '
 
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                        'Commit these to the bound branch or use --force to '
 
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                        'throw them away.'))
 
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            except errors.BoundBranchConnectionFailure, e:
 
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                raise errors.BzrCommandError(gettext(
 
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                        'Unable to connect to current master branch %(target)s: '
 
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                        '%(error)s To switch anyway, use --force.') %
 
118
                        e.__dict__)
 
119
            b.lock_write()
 
120
            try:
 
121
                b.set_bound_location(None)
 
122
                b.pull(to_branch, overwrite=True,
 
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                       possible_transports=possible_transports)
 
124
                b.set_bound_location(to_branch.base)
 
125
                b.set_parent(b.get_master_branch().get_parent())
 
126
            finally:
 
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                b.unlock()
 
128
        else:
 
129
            # If this is a standalone tree and the new branch
 
130
            # is derived from this one, create a lightweight checkout.
 
131
            b.lock_read()
 
132
            try:
 
133
                graph = b.repository.get_graph(to_branch.repository)
 
134
                if (b.bzrdir._format.colocated_branches and
 
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                     (force or graph.is_ancestor(b.last_revision(),
 
136
                        to_branch.last_revision()))):
 
137
                    b.bzrdir.destroy_branch()
 
138
                    b.bzrdir.set_branch_reference(to_branch, name="")
 
139
                else:
 
140
                    raise errors.BzrCommandError(gettext('Cannot switch a branch, '
 
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                        'only a checkout.'))
 
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            finally:
 
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                b.unlock()
 
144
 
 
145
 
 
146
def _any_local_commits(this_branch, possible_transports):
 
147
    """Does this branch have any commits not in the master branch?"""
 
148
    last_rev = revision.ensure_null(this_branch.last_revision())
 
149
    if last_rev != revision.NULL_REVISION:
 
150
        other_branch = this_branch.get_master_branch(possible_transports)
 
151
        this_branch.lock_read()
 
152
        other_branch.lock_read()
 
153
        try:
 
154
            other_last_rev = other_branch.last_revision()
 
155
            graph = this_branch.repository.get_graph(
 
156
                other_branch.repository)
 
157
            if not graph.is_ancestor(last_rev, other_last_rev):
 
158
                return True
 
159
        finally:
 
160
            other_branch.unlock()
 
161
            this_branch.unlock()
 
162
    return False
 
163
 
 
164
 
 
165
def _update(tree, source_repository, quiet=False, revision_id=None,
 
166
            restore_uncommitted=False):
 
167
    """Update a working tree to the latest revision of its branch.
 
168
 
 
169
    :param tree: the working tree
 
170
    :param source_repository: repository holding the revisions
 
171
    :param restore_uncommitted: restore any uncommitted changes in the branch.
 
172
    """
 
173
    if restore_uncommitted:
 
174
        tree.lock_write()
 
175
    else:
 
176
        tree.lock_tree_write()
 
177
    try:
 
178
        to_branch = tree.branch
 
179
        if revision_id is None:
 
180
            revision_id = to_branch.last_revision()
 
181
        if tree.last_revision() == revision_id:
 
182
            if not quiet:
 
183
                note(gettext("Tree is up to date at revision %d."), to_branch.revno())
 
184
        else:
 
185
            base_tree = source_repository.revision_tree(tree.last_revision())
 
186
            merge.Merge3Merger(tree, tree, base_tree,
 
187
                               to_branch.repository.revision_tree(revision_id))
 
188
            tree.set_last_revision(to_branch.last_revision())
 
189
            if not quiet:
 
190
                note(gettext('Updated to revision %d.') % to_branch.revno())
 
191
        if restore_uncommitted:
 
192
            tree.restore_uncommitted()
 
193
    finally:
 
194
        tree.unlock()