/brz/remove-bazaar

# Copyright (C) 2005, 2006, 2007 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., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA

"""Tests for bzrdir implementations - tests a bzrdir format."""

import os

import re

import sys

import bzrlib

from bzrlib import (

    bzrdir,

    errors,

    repository,

    transactions,

    )

from bzrlib.branch import Branch, needs_read_lock, needs_write_lock

from bzrlib.delta import TreeDelta

from bzrlib.errors import (FileExists,

                           NoSuchRevision,

                           NoSuchFile,

                           UninitializableFormat,

                           NotBranchError,

                           )

from bzrlib.inventory import Inventory, InventoryDirectory

from bzrlib.revision import NULL_REVISION

from bzrlib.repofmt import knitrepo

from bzrlib.tests import TestCase, TestCaseWithTransport, TestSkipped

from bzrlib.tests.bzrdir_implementations.test_bzrdir import TestCaseWithBzrDir

from bzrlib.trace import mutter

from bzrlib.transport import get_transport

from bzrlib.upgrade import upgrade

from bzrlib.workingtree import WorkingTree

class TestCaseWithRepository(TestCaseWithBzrDir):

    def make_branch(self, relpath, format=None):

        repo = self.make_repository(relpath, format=None)

        return repo.bzrdir.create_branch()

    def make_repository(self, relpath, format=None):

        made_control = self.make_bzrdir(relpath)

        return self.repository_format.initialize(made_control)

class TestRepository(TestCaseWithRepository):

    def test_clone_to_default_format(self):

        #TODO: Test that cloning a repository preserves all the information

        # such as signatures[not tested yet] etc etc.

        # when changing to the current default format.

        tree_a = self.make_branch_and_tree('a')

        self.build_tree(['a/foo'])

        tree_a.add('foo', 'file1')

        tree_a.commit('rev1', rev_id='rev1')

        bzrdirb = self.make_bzrdir('b')

        repo_b = tree_a.branch.repository.clone(bzrdirb)

        tree_b = repo_b.revision_tree('rev1')

        tree_b.get_file_text('file1')

        rev1 = repo_b.get_revision('rev1')

    def test_supports_rich_root(self):

        tree = self.make_branch_and_tree('a')

        tree.commit('')

        second_revision = tree.commit('')

        inv = tree.branch.repository.revision_tree(second_revision).inventory

        rich_root = (inv.root.revision != second_revision)

        self.assertEqual(rich_root, 

                         tree.branch.repository.supports_rich_root())

    def test_clone_specific_format(self):

        """todo"""

    def test_format_initialize_find_open(self):

        # loopback test to check the current format initializes to itself.

        if not self.repository_format.is_supported():

            # unsupported formats are not loopback testable

            # because the default open will not open them and

            # they may not be initializable.

            return

        # supported formats must be able to init and open

        t = get_transport(self.get_url())

        readonly_t = get_transport(self.get_readonly_url())

        made_control = self.bzrdir_format.initialize(t.base)

        made_repo = self.repository_format.initialize(made_control)

        self.failUnless(isinstance(made_repo, repository.Repository))

        self.assertEqual(made_control, made_repo.bzrdir)

        # find it via bzrdir opening:

        opened_control = bzrdir.BzrDir.open(readonly_t.base)

        direct_opened_repo = opened_control.open_repository()

        self.assertEqual(direct_opened_repo.__class__, made_repo.__class__)

        self.assertEqual(opened_control, direct_opened_repo.bzrdir)

        self.failUnless(isinstance(direct_opened_repo._format,

                        self.repository_format.__class__))

        # find it via Repository.open

        opened_repo = repository.Repository.open(readonly_t.base)

        self.failUnless(isinstance(opened_repo, made_repo.__class__))

        self.assertEqual(made_repo._format.__class__,

                         opened_repo._format.__class__)

        # if it has a unique id string, can we probe for it ?

        try:

            self.repository_format.get_format_string()

        except NotImplementedError:

            return

        self.assertEqual(self.repository_format,

                         repository.RepositoryFormat.find_format(opened_control))

    def test_create_repository(self):

        # bzrdir can construct a repository for itself.

        if not self.bzrdir_format.is_supported():

            # unsupported formats are not loopback testable

            # because the default open will not open them and

            # they may not be initializable.

            return

        t = get_transport(self.get_url())

        made_control = self.bzrdir_format.initialize(t.base)

        made_repo = made_control.create_repository()

        self.failUnless(isinstance(made_repo, repository.Repository))

        self.assertEqual(made_control, made_repo.bzrdir)

    def test_create_repository_shared(self):

        # bzrdir can construct a shared repository.

        if not self.bzrdir_format.is_supported():

            # unsupported formats are not loopback testable

            # because the default open will not open them and

            # they may not be initializable.

            return

        t = get_transport(self.get_url())

        made_control = self.bzrdir_format.initialize(t.base)

        try:

            made_repo = made_control.create_repository(shared=True)

        except errors.IncompatibleFormat:

            # not all repository formats understand being shared, or

            # may only be shared in some circumstances.

            return

        self.failUnless(isinstance(made_repo, repository.Repository))

        self.assertEqual(made_control, made_repo.bzrdir)

        self.assertTrue(made_repo.is_shared())

    def test_revision_tree(self):

        wt = self.make_branch_and_tree('.')

        wt.set_root_id('fixed-root')

        wt.commit('lala!', rev_id='revision-1', allow_pointless=True)

        tree = wt.branch.repository.revision_tree('revision-1')

        self.assertEqual('revision-1', tree.inventory.root.revision) 

        expected = InventoryDirectory('fixed-root', '', None)

        expected.revision = 'revision-1'

        self.assertEqual([('', 'V', 'directory', 'fixed-root', expected)],

                         list(tree.list_files(include_root=True)))

        tree = wt.branch.repository.revision_tree(None)

        self.assertEqual([], list(tree.list_files(include_root=True)))

        tree = wt.branch.repository.revision_tree(NULL_REVISION)

        self.assertEqual([], list(tree.list_files(include_root=True)))

    def test_fetch(self):

        # smoke test fetch to ensure that the convenience function works.

        # it is defined as a convenience function with the underlying 

        # functionality provided by an InterRepository

        tree_a = self.make_branch_and_tree('a')

        self.build_tree(['a/foo'])

        tree_a.add('foo', 'file1')

        tree_a.commit('rev1', rev_id='rev1')

        # fetch with a default limit (grab everything)

        repo = bzrdir.BzrDir.create_repository(self.get_url('b'))

        if (tree_a.branch.repository._format.rich_root_data and not

            repo._format.rich_root_data):

            raise TestSkipped('Cannot fetch from model2 to model1')

        repo.fetch(tree_a.branch.repository,

                   revision_id=None,

                   pb=bzrlib.progress.DummyProgress())

    def test_fetch_knit2(self):

        tree_a = self.make_branch_and_tree('a')

        self.build_tree(['a/foo'])

        tree_a.add('foo', 'file1')

        tree_a.commit('rev1', rev_id='rev1')

        # fetch with a default limit (grab everything)

        f = bzrdir.BzrDirMetaFormat1()

        f._repository_format = knitrepo.RepositoryFormatKnit2()

        os.mkdir('b')

        b_bzrdir = f.initialize(self.get_url('b'))

        repo = b_bzrdir.create_repository()

        repo.fetch(tree_a.branch.repository,

                   revision_id=None,

                   pb=bzrlib.progress.DummyProgress())

        rev1_tree = repo.revision_tree('rev1')

        lines = rev1_tree.get_file_lines(rev1_tree.inventory.root.file_id)

        self.assertEqual([], lines)

        b_branch = b_bzrdir.create_branch()

        b_branch.pull(tree_a.branch)

        tree_b = b_bzrdir.create_workingtree()

        tree_b.commit('no change', rev_id='rev2')

        rev2_tree = repo.revision_tree('rev2')

        self.assertEqual('rev1', rev2_tree.inventory.root.revision)

    def test_get_revision_delta(self):

        tree_a = self.make_branch_and_tree('a')

        self.build_tree(['a/foo'])

        tree_a.add('foo', 'file1')

        tree_a.commit('rev1', rev_id='rev1')

        self.build_tree(['a/vla'])

        tree_a.add('vla', 'file2')

        tree_a.commit('rev2', rev_id='rev2')

        delta = tree_a.branch.repository.get_revision_delta('rev1')

        self.assertIsInstance(delta, TreeDelta)

        self.assertEqual([('foo', 'file1', 'file')], delta.added)

        delta = tree_a.branch.repository.get_revision_delta('rev2')

        self.assertIsInstance(delta, TreeDelta)

        self.assertEqual([('vla', 'file2', 'file')], delta.added)

    def test_clone_bzrdir_repository_revision(self):

        # make a repository with some revisions,

        # and clone it, this should not have unreferenced revisions.

        # also: test cloning with a revision id of NULL_REVISION -> empty repo.

        raise TestSkipped('revision limiting is not implemented yet.')

    def test_clone_repository_basis_revision(self):

        raise TestSkipped('the use of a basis should not add noise data to the result.')

    def test_clone_repository_incomplete_source_with_basis(self):

        # ensure that basis really does grab from the basis by having incomplete source

        tree = self.make_branch_and_tree('commit_tree')

        self.build_tree(['foo'], transport=tree.bzrdir.transport.clone('..'))

        tree.add('foo')

        tree.commit('revision 1', rev_id='1')

        source = self.make_repository('source')

        # this gives us an incomplete repository

        tree.bzrdir.open_repository().copy_content_into(source)

        tree.commit('revision 2', rev_id='2', allow_pointless=True)

        self.assertFalse(source.has_revision('2'))

        target = source.bzrdir.clone(self.get_url('target'), basis=tree.bzrdir)

        self.assertTrue(target.open_repository().has_revision('2'))

    def test_clone_shared_no_tree(self):

        # cloning a shared repository keeps it shared

        # and preserves the make_working_tree setting.

        made_control = self.make_bzrdir('source')

        try:

            made_repo = made_control.create_repository(shared=True)

        except errors.IncompatibleFormat:

            # not all repository formats understand being shared, or

            # may only be shared in some circumstances.

            return

        made_repo.set_make_working_trees(False)

        result = made_control.clone(self.get_url('target'))

        self.failUnless(isinstance(made_repo, repository.Repository))

        self.assertEqual(made_control, made_repo.bzrdir)

        self.assertTrue(result.open_repository().is_shared())

        self.assertFalse(result.open_repository().make_working_trees())

    def test_upgrade_preserves_signatures(self):

        wt = self.make_branch_and_tree('source')

        wt.commit('A', allow_pointless=True, rev_id='A')

        wt.branch.repository.sign_revision('A',

            bzrlib.gpg.LoopbackGPGStrategy(None))

        old_signature = wt.branch.repository.get_signature_text('A')

        try:

            old_format = bzrdir.BzrDirFormat.get_default_format()

            # This gives metadir branches something they can convert to.

            # it would be nice to have a 'latest' vs 'default' concept.

            format = bzrdir.format_registry.make_bzrdir('experimental-knit2')

            upgrade(wt.basedir, format=format)

        except errors.UpToDateFormat:

            # this is in the most current format already.

            return

        except errors.BadConversionTarget, e:

            raise TestSkipped(str(e))

        wt = WorkingTree.open(wt.basedir)

        new_signature = wt.branch.repository.get_signature_text('A')

        self.assertEqual(old_signature, new_signature)

    def test_exposed_versioned_files_are_marked_dirty(self):

        repo = self.make_repository('.')

        repo.lock_write()

        inv = repo.get_inventory_weave()

        repo.unlock()

        self.assertRaises(errors.OutSideTransaction, inv.add_lines, 'foo', [], [])

    def test_format_description(self):

        repo = self.make_repository('.')

        text = repo._format.get_format_description()

        self.failUnless(len(text))

    def assertMessageRoundtrips(self, message):

        """Assert that message roundtrips to a repository and back intact."""

        tree = self.make_branch_and_tree('.')

        tree.commit(message, rev_id='a', allow_pointless=True)

        rev = tree.branch.repository.get_revision('a')

        # we have to manually escape this as we dont try to

        # roundtrip xml invalid characters at this point.

        # when escaping is moved to the serialiser, this test

        # can check against the literal message rather than

        # this escaped version.

        escaped_message, escape_count = re.subn(

            u'[^\x09\x0A\x0D\u0020-\uD7FF\uE000-\uFFFD]+',

            lambda match: match.group(0).encode('unicode_escape'),

            message)

        escaped_message= re.sub('\r', '\n', escaped_message)

        self.assertEqual(rev.message, escaped_message)

        # insist the class is unicode no matter what came in for 

        # consistency.

        self.assertIsInstance(rev.message, unicode)

    def test_commit_unicode_message(self):

        # a siple unicode message should be preserved

        self.assertMessageRoundtrips(u'foo bar gamm\xae plop')

    def test_commit_unicode_control_characters(self):

        # a unicode message with control characters should roundtrip too.

        self.assertMessageRoundtrips(

            "All 8-bit chars: " +  ''.join([unichr(x) for x in range(256)]))

    def test_check_repository(self):

        """Check a fairly simple repository's history"""

        tree = self.make_branch_and_tree('.')

        tree.commit('initial empty commit', rev_id='a-rev',

                    allow_pointless=True)

        result = tree.branch.repository.check(['a-rev'])

        # writes to log; should accept both verbose or non-verbose

        result.report_results(verbose=True)

        result.report_results(verbose=False)

    def test_get_revisions(self):

        tree = self.make_branch_and_tree('.')

        tree.commit('initial empty commit', rev_id='a-rev',

                    allow_pointless=True)

        tree.commit('second empty commit', rev_id='b-rev',

                    allow_pointless=True)

        tree.commit('third empty commit', rev_id='c-rev',

                    allow_pointless=True)

        repo = tree.branch.repository

        revision_ids = ['a-rev', 'b-rev', 'c-rev']

        revisions = repo.get_revisions(revision_ids)

        assert len(revisions) == 3, repr(revisions)

        zipped = zip(revisions, revision_ids)

        self.assertEqual(len(zipped), 3)

        for revision, revision_id in zipped:

            self.assertEqual(revision.revision_id, revision_id)

            self.assertEqual(revision, repo.get_revision(revision_id))

    def test_root_entry_has_revision(self):

        tree = self.make_branch_and_tree('.')

        tree.commit('message', rev_id='rev_id')

        self.assertEqual('rev_id', tree.basis_tree().inventory.root.revision)

        rev_tree = tree.branch.repository.revision_tree(tree.get_parent_ids()[0])

        self.assertEqual('rev_id', rev_tree.inventory.root.revision)

    def test_create_basis_inventory(self):

        # Needs testing here because differences between repo and working tree

        # basis inventory formats can lead to bugs.

        t = self.make_branch_and_tree('.')

        b = t.branch

        open('a', 'wb').write('a\n')

        t.add('a')

        t.commit('a', rev_id='r1')

        t._control_files.get_utf8('basis-inventory-cache')

        basis_inv = t.basis_tree().inventory

        self.assertEquals('r1', basis_inv.revision_id)

        store_inv = b.repository.get_inventory('r1')

        self.assertEquals(store_inv._byid, basis_inv._byid)

        open('b', 'wb').write('b\n')

        t.add('b')

        t.commit('b', rev_id='r2')

        t._control_files.get_utf8('basis-inventory-cache')

        basis_inv_txt = t.read_basis_inventory()

        basis_inv = bzrlib.xml6.serializer_v6.read_inventory_from_string(basis_inv_txt)

        self.assertEquals('r2', basis_inv.revision_id)

        store_inv = b.repository.get_inventory('r2')

        self.assertEquals(store_inv._byid, basis_inv._byid)

    def test_upgrade_from_format4(self):

        from bzrlib.tests.test_upgrade import _upgrade_dir_template

        if self.repository_format.get_format_description() \

            == "Repository format 4":

            raise TestSkipped('Cannot convert format-4 to itself')

        self.build_tree_contents(_upgrade_dir_template)

        old_repodir = bzrlib.bzrdir.BzrDir.open_unsupported('.')

        old_repo_format = old_repodir.open_repository()._format

        format = self.repository_format._matchingbzrdir

        try:

            format.repository_format = self.repository_format

        except AttributeError:

            pass

        upgrade('.', format)

    def test_pointless_commit(self):

        tree = self.make_branch_and_tree('.')

        self.assertRaises(errors.PointlessCommit, tree.commit, 'pointless',

                          allow_pointless=False)

        tree.commit('pointless', allow_pointless=True)

class TestCaseWithComplexRepository(TestCaseWithRepository):

    def setUp(self):

        super(TestCaseWithComplexRepository, self).setUp()

        tree_a = self.make_branch_and_tree('a')

        self.bzrdir = tree_a.branch.bzrdir

        # add a corrupt inventory 'orphan'

        # this may need some generalising for knits.

        inv_file = tree_a.branch.repository.control_weaves.get_weave(

            'inventory', 

            tree_a.branch.repository.get_transaction())

        inv_file.add_lines('orphan', [], [])

        # add a real revision 'rev1'

        tree_a.commit('rev1', rev_id='rev1', allow_pointless=True)

        # add a real revision 'rev2' based on rev1

        tree_a.commit('rev2', rev_id='rev2', allow_pointless=True)

        # add a reference to a ghost

        tree_a.add_parent_tree_id('ghost1')

        tree_a.commit('rev3', rev_id='rev3', allow_pointless=True)

        # add another reference to a ghost, and a second ghost.

        tree_a.add_parent_tree_id('ghost1')

        tree_a.add_parent_tree_id('ghost2')

        tree_a.commit('rev4', rev_id='rev4', allow_pointless=True)

    def test_revision_trees(self):

        revision_ids = ['rev1', 'rev2', 'rev3', 'rev4']

        repository = self.bzrdir.open_repository()

        trees1 = list(repository.revision_trees(revision_ids))

        trees2 = [repository.revision_tree(t) for t in revision_ids]

        assert len(trees1) == len(trees2)

        for tree1, tree2 in zip(trees1, trees2):

            assert not tree2.changes_from(tree1).has_changed()

    def test_get_deltas_for_revisions(self):

        repository = self.bzrdir.open_repository()

        revisions = [repository.get_revision(r) for r in 

                     ['rev1', 'rev2', 'rev3', 'rev4']]

        deltas1 = list(repository.get_deltas_for_revisions(revisions))

        deltas2 = [repository.get_revision_delta(r.revision_id) for r in

                   revisions]

        assert deltas1 == deltas2

    def test_all_revision_ids(self):

        # all_revision_ids -> all revisions

        self.assertEqual(['rev1', 'rev2', 'rev3', 'rev4'],

                         self.bzrdir.open_repository().all_revision_ids())

    def test_get_ancestry_missing_revision(self):

        # get_ancestry(revision that is in some data but not fully installed

        # -> NoSuchRevision

        self.assertRaises(errors.NoSuchRevision,

                          self.bzrdir.open_repository().get_ancestry, 'orphan')

    def test_get_revision_graph(self):

        # we can get a mapping of id->parents for the entire revision graph or bits thereof.

        self.assertEqual({'rev1':[],

                          'rev2':['rev1'],

                          'rev3':['rev2'],

                          'rev4':['rev3'],

                          },

                         self.bzrdir.open_repository().get_revision_graph(None))

        self.assertEqual({'rev1':[]},

                         self.bzrdir.open_repository().get_revision_graph('rev1'))

        self.assertEqual({'rev1':[],

                          'rev2':['rev1']},

                         self.bzrdir.open_repository().get_revision_graph('rev2'))

        self.assertRaises(NoSuchRevision,

                          self.bzrdir.open_repository().get_revision_graph,

                          'orphan')

        # and ghosts are not mentioned

        self.assertEqual({'rev1':[],

                          'rev2':['rev1'],

                          'rev3':['rev2'],

                          },

                         self.bzrdir.open_repository().get_revision_graph('rev3'))

        # and we can ask for the NULLREVISION graph

        self.assertEqual({},

            self.bzrdir.open_repository().get_revision_graph(NULL_REVISION))

    def test_get_revision_graph_with_ghosts(self):

        # we can get a graph object with roots, ghosts, ancestors and

        # descendants.

        repo = self.bzrdir.open_repository()

        graph = repo.get_revision_graph_with_ghosts([])

        self.assertEqual(set(['rev1']), graph.roots)

        self.assertEqual(set(['ghost1', 'ghost2']), graph.ghosts)

        self.assertEqual({'rev1':[],

                          'rev2':['rev1'],

                          'rev3':['rev2', 'ghost1'],

                          'rev4':['rev3', 'ghost1', 'ghost2'],

                          },

                          graph.get_ancestors())

        self.assertEqual({'ghost1':{'rev3':1, 'rev4':1},

                          'ghost2':{'rev4':1},

                          'rev1':{'rev2':1},

                          'rev2':{'rev3':1},

                          'rev3':{'rev4':1},

                          'rev4':{},

                          },

                          graph.get_descendants())

        # and we can ask for the NULLREVISION graph

        graph = repo.get_revision_graph_with_ghosts([NULL_REVISION])

        self.assertEqual({}, graph.get_ancestors())

        self.assertEqual({}, graph.get_descendants())

    def test_reserved_id(self):

        repo = self.make_repository('repository')

        self.assertRaises(errors.ReservedId, repo.add_inventory, 'reserved:',

                          None, None)

        self.assertRaises(errors.ReservedId, repo.add_revision, 'reserved:',

                          None)

class TestCaseWithCorruptRepository(TestCaseWithRepository):

    def setUp(self):

        super(TestCaseWithCorruptRepository, self).setUp()

        # a inventory with no parents and the revision has parents..

        # i.e. a ghost.

        repo = self.make_repository('inventory_with_unnecessary_ghost')

        inv = Inventory(revision_id = 'ghost')

        inv.root.revision = 'ghost'

        sha1 = repo.add_inventory('ghost', inv, [])

        rev = bzrlib.revision.Revision(timestamp=0,

                                       timezone=None,

                                       committer="Foo Bar <foo@example.com>",

                                       message="Message",

                                       inventory_sha1=sha1,

                                       revision_id='ghost')

        rev.parent_ids = ['the_ghost']

        repo.add_revision('ghost', rev)

        inv = Inventory(revision_id = 'the_ghost')

        inv.root.revision = 'the_ghost'

        sha1 = repo.add_inventory('the_ghost', inv, [])

        rev = bzrlib.revision.Revision(timestamp=0,

                                       timezone=None,

                                       committer="Foo Bar <foo@example.com>",

                                       message="Message",

                                       inventory_sha1=sha1,

                                       revision_id='the_ghost')

        rev.parent_ids = []

        repo.add_revision('the_ghost', rev)

        # check its setup usefully

        inv_weave = repo.get_inventory_weave()

        self.assertEqual(['ghost'], inv_weave.get_ancestry(['ghost']))

    def test_corrupt_revision_access_asserts_if_reported_wrong(self):

        repo = repository.Repository.open('inventory_with_unnecessary_ghost')

        reported_wrong = False

        try:

            if repo.get_ancestry('ghost') != [None, 'the_ghost', 'ghost']:

                reported_wrong = True

        except errors.CorruptRepository:

            # caught the bad data:

            return

        if not reported_wrong:

            return

        self.assertRaises(errors.CorruptRepository, repo.get_revision, 'ghost')

    def test_corrupt_revision_get_revision_reconcile(self):

        repo = repository.Repository.open('inventory_with_unnecessary_ghost')

        repo.get_revision_reconcile('ghost')

class TestEscaping(TestCaseWithTransport):

    """Test that repositories can be stored correctly on VFAT transports.

    Makes sure we have proper escaping of invalid characters, etc.

    It'd be better to test all operations on the FakeVFATTransportDecorator,

    but working trees go straight to the os not through the Transport layer.

    Therefore we build some history first in the regular way and then 

    check it's safe to access for vfat.

    """

    def test_on_vfat(self):

        FOO_ID = 'foo<:>ID'

        REV_ID = 'revid-1'

        wt = self.make_branch_and_tree('repo')

        self.build_tree(["repo/foo"], line_endings='binary')

        # add file with id containing wierd characters

        wt.add(['foo'], [FOO_ID])

        wt.commit('this is my new commit', rev_id=REV_ID)

        # now access over vfat; should be safe

        branch = bzrdir.BzrDir.open('vfat+' + self.get_url('repo')).open_branch()

        revtree = branch.repository.revision_tree(REV_ID)

        contents = revtree.get_file_text(FOO_ID)

        self.assertEqual(contents, 'contents of repo/foo\n')