Tarball conversion

1 files changed, 175 insertions, 0 deletions

diff --git a/bzrlib/switch.py b/bzrlib/switch.py
new file mode 100644
index 0000000..6f8e75e
--- /dev/null
+++ b/bzrlib/switch.py
@@ -0,0 +1,175 @@
+# 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 bzrlib import errors, merge, revision
+from bzrlib.branch import Branch
+from bzrlib.i18n import gettext
+from bzrlib.trace import note
+
+def _run_post_switch_hooks(control_dir, to_branch, force, revision_id):
+    from bzrlib.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):
+    """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.
+    """
+    _check_pending_merges(control_dir, force)
+    try:
+        source_repository = control_dir.open_branch().repository
+    except errors.NotBranchError:
+        source_repository = to_branch.repository
+    to_branch.lock_read()
+    try:
+        _set_branch_location(control_dir, to_branch, force)
+    finally:
+        to_branch.unlock()
+    tree = control_dir.open_workingtree()
+    _update(tree, source_repository, quiet, revision_id)
+    _run_post_switch_hooks(control_dir, to_branch, force, revision_id)
+
+def _check_pending_merges(control, force=False):
+    """Check that there are no outstanding pending merges before switching.
+
+    :param control: ControlDir of the branch to check
+    """
+    try:
+        tree = control.open_workingtree()
+    except errors.NotBranchError, ex:
+        # Lightweight checkout and branch is no longer there
+        if force:
+            return
+        else:
+            raise ex
+    # XXX: Should the tree be locked for get_parent_ids?
+    existing_pending_merges = tree.get_parent_ids()[1:]
+    if len(existing_pending_merges) > 0:
+        raise errors.BzrCommandError(gettext('Pending merges must be '
+            'committed or reverted before using switch.'))
+
+
+def _set_branch_location(control, to_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 = control.open_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, e:
+                raise errors.BzrCommandError(gettext(
+                        'Unable to connect to current master branch %(target)s: '
+                        '%(error)s To switch anyway, use --force.') %
+                        e.__dict__)
+            b.lock_write()
+            try:
+                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())
+            finally:
+                b.unlock()
+        else:
+            # If this is a standalone tree and the new branch
+            # is derived from this one, create a lightweight checkout.
+            b.lock_read()
+            try:
+                graph = b.repository.get_graph(to_branch.repository)
+                if (b.bzrdir._format.colocated_branches and
+                     (force or graph.is_ancestor(b.last_revision(),
+                        to_branch.last_revision()))):
+                    b.bzrdir.destroy_branch()
+                    b.bzrdir.set_branch_reference(to_branch, name="")
+                else:
+                    raise errors.BzrCommandError(gettext('Cannot switch a branch, '
+                        'only a checkout.'))
+            finally:
+                b.unlock()
+
+
+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)
+        this_branch.lock_read()
+        other_branch.lock_read()
+        try:
+            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
+        finally:
+            other_branch.unlock()
+            this_branch.unlock()
+    return False
+
+
+def _update(tree, source_repository, quiet=False, revision_id=None):
+    """Update a working tree to the latest revision of its branch.
+
+    :param tree: the working tree
+    :param source_repository: repository holding the revisions
+    """
+    tree.lock_tree_write()
+    try:
+        to_branch = tree.branch
+        if revision_id is None:
+            revision_id = to_branch.last_revision()
+        if tree.last_revision() == revision_id:
+            if not quiet:
+                note(gettext("Tree is up to date at revision %d."), to_branch.revno())
+            return
+        base_tree = source_repository.revision_tree(tree.last_revision())
+        merge.Merge3Merger(tree, tree, base_tree, to_branch.repository.revision_tree(revision_id))
+        tree.set_last_revision(to_branch.last_revision())
+        if not quiet:
+            note(gettext('Updated to revision %d.') % to_branch.revno())
+    finally:
+        tree.unlock()