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# Copyright (C) 2015  The Software Heritage developers
# See the AUTHORS file at the top-level directory of this distribution
# License: GNU General Public License version 3, or any later version
# See top-level LICENSE file for more information

Antoine R. Dumont's avatar
Antoine R. Dumont committed
import shutil
import subprocess
from nose.plugins.attrib import attr
from nose.tools import istest

from swh.model import git


class GitHashlib(unittest.TestCase):
    def setUp(self):
        self.tree_data = b''.join([b'40000 barfoo\0',
                                   bytes.fromhex('c3020f6bf135a38c6df'
                                                 '3afeb5fb38232c5e07087'),
                                   b'100644 blah\0',
                                   bytes.fromhex('63756ef0df5e4f10b6efa'
                                                 '33cfe5c758749615f20'),
                                   b'100644 hello\0',
                                   bytes.fromhex('907b308167f0880fb2a'
                                                 '5c0e1614bb0c7620f9dc3')])

        self.commit_data = """tree 1c61f7259dcb770f46b194d941df4f08ff0a3970
author Antoine R. Dumont (@ardumont) <antoine.romain.dumont@gmail.com> 1444054085 +0200
committer Antoine R. Dumont (@ardumont) <antoine.romain.dumont@gmail.com> 1444054085 +0200

initial
""".encode('utf-8')  # NOQA
        self.tag_data = """object 24d012aaec0bc5a4d2f62c56399053d6cc72a241
type commit
tag 0.0.1
tagger Antoine R. Dumont (@ardumont) <antoine.romain.dumont@gmail.com> 1444225145 +0200

blah
""".encode('utf-8')  # NOQA

        self.checksums = {
            'tree_sha1_git': bytes.fromhex('ac212302c45eada382b27bfda795db'
                                           '121dacdb1c'),
            'commit_sha1_git': bytes.fromhex('e960570b2e6e2798fa4cfb9af2c399'
                                             'd629189653'),
            'tag_sha1_git': bytes.fromhex('bc2b99ba469987bcf1272c189ed534'
                                          'e9e959f120'),
        }

    @istest
    def compute_directory_git_sha1(self):
        # given
        dirpath = 'some-dir-path'
        hashes = {
            dirpath: [{'perms': git.GitPerm.TREE,
                       'type': git.GitType.TREE,
                       'name': b'barfoo',
                       'sha1_git': bytes.fromhex('c3020f6bf135a38c6df'
                                                 '3afeb5fb38232c5e07087')},
                      {'perms': git.GitPerm.BLOB,
                       'type': git.GitType.BLOB,
                       'name': b'hello',
                       'sha1_git': bytes.fromhex('907b308167f0880fb2a'
                                                 '5c0e1614bb0c7620f9dc3')},
                      {'perms': git.GitPerm.BLOB,
                       'type': git.GitType.BLOB,
                       'name': b'blah',
                       'sha1_git': bytes.fromhex('63756ef0df5e4f10b6efa'
                                                 '33cfe5c758749615f20')}]
        }

        # when
        checksum = git.compute_directory_git_sha1(dirpath, hashes)

        # then
        self.assertEqual(checksum, self.checksums['tree_sha1_git'])

    @istest
    def compute_revision_sha1_git(self):
        # given
        tree_hash = bytes.fromhex('1c61f7259dcb770f46b194d941df4f08ff0a3970')
        revision = {
            'author': {
                'name': b'Antoine R. Dumont (@ardumont)',
                'email': b'antoine.romain.dumont@gmail.com',
            },
            'date': {
                'timestamp': 1444054085,
                'offset': 120,
            },
            'committer': {
                'name': b'Antoine R. Dumont (@ardumont)',
                'email': b'antoine.romain.dumont@gmail.com',
            },
            'committer_date': {
                'timestamp': 1444054085,
                'offset': 120,
            },
            'message': b'initial\n',
            'type': 'tar',
            'directory': tree_hash,
            'parents': [],
        }

        # when
        checksum = git.compute_revision_sha1_git(revision)

        # then
        self.assertEqual(checksum, self.checksums['commit_sha1_git'])

    @istest
    def compute_release_sha1_git(self):
        # given
        revision_hash = bytes.fromhex('24d012aaec0bc5a4d2f62c56399053'
                                      'd6cc72a241')
        release = {
            'name': b'0.0.1',
            'author': {
                'name': b'Antoine R. Dumont (@ardumont)',
                'email': b'antoine.romain.dumont@gmail.com',
            },
            'date': {
                'timestamp': 1444225145,
                'offset': 120,
            },
            'message': b'blah\n',
            'target_type': 'revision',
            'target': revision_hash,
        }

        # when
        checksum = git.compute_release_sha1_git(release)

        # then
        self.assertEqual(checksum, self.checksums['tag_sha1_git'])
class GitHashWalkArborescenceTree(unittest.TestCase):
    """Root class to ease walk and git hash testing without side-effecty
    problems.
    def setUp(self):
        self.tmp_root_path = tempfile.mkdtemp().encode('utf-8')

        start_path = os.path.dirname(__file__).encode('utf-8')
        pkg_doc_linux_r11 = os.path.join(start_path,
                                         b'../../../..',
                                         b'swh-storage-testdata',
                                         b'dir-folders',
                                         b'sample-folder.tgz')
        self.root_path = os.path.join(self.tmp_root_path, b'sample-folder')

        # uncompress the sample folder
        subprocess.check_output(
            ['tar', 'xvf', pkg_doc_linux_r11, '-C', self.tmp_root_path])
    def tearDown(self):
        if os.path.exists(self.tmp_root_path):
            shutil.rmtree(self.tmp_root_path)

class GitHashFromScratch(GitHashWalkArborescenceTree):
    """Test the main `walk_and_compute_sha1_from_directory` algorithm that
    scans and compute the disk for checksums.

    """
    @istest
    def walk_and_compute_sha1_from_directory(self):
        # make a temporary arborescence tree to hash without ignoring anything
        # same as previous behavior
        walk0 = git.walk_and_compute_sha1_from_directory(self.tmp_root_path)

        keys0 = list(walk0.keys())
        path_excluded = os.path.join(self.tmp_root_path,
                                     b'sample-folder',
                                     b'foo')
        self.assertTrue(path_excluded in keys0)  # it is not excluded here

        # make the same temporary arborescence tree to hash with ignoring one
        # folder foo
        walk1 = git.walk_and_compute_sha1_from_directory(
            self.tmp_root_path,
            dir_ok_fn=lambda dirpath: b'sample-folder/foo' not in dirpath)
        keys1 = list(walk1.keys())
        self.assertTrue(path_excluded not in keys1)

        # remove the keys that can't be the same (due to hash definition)
        # Those are the top level folders
        keys_diff = [self.tmp_root_path,
                     os.path.join(self.tmp_root_path, b'sample-folder'),
                     git.ROOT_TREE_KEY]
        for k in keys_diff:
            self.assertNotEquals(walk0[k], walk1[k])

        # The remaining keys (bottom path) should have exactly the same hashes
        # as before
        keys = set(keys1) - set(keys_diff)
        actual_walk1 = {}
        for k in keys:
            self.assertEquals(walk0[k], walk1[k])
            actual_walk1[k] = walk1[k]

        expected_checksums = {
            os.path.join(self.tmp_root_path, b'sample-folder/empty-folder'): [],                                            # noqa
            os.path.join(self.tmp_root_path, b'sample-folder/bar/barfoo'): [{                                               # noqa
                'type': git.GitType.BLOB,                                                                                   # noqa
                'sha256': b'=\xb5\xae\x16\x80U\xbc\xd9:M\x08(]\xc9\x9f\xfe\xe2\x883\x03\xb2?\xac^\xab\x85\x02s\xa8\xeaUF',  # noqa
                'name': b'another-quote.org',                                                                               # noqa
                'path': os.path.join(self.tmp_root_path, b'sample-folder/bar/barfoo/another-quote.org'),                    # noqa
                'perms': git.GitPerm.BLOB,                                                                                  # noqa
                'sha1': b'\x90\xa6\x13\x8b\xa5\x99\x15&\x1e\x17\x99H8j\xa1\xcc*\xa9"\n',                                    # noqa
                'sha1_git': b'\x136\x93\xb1%\xba\xd2\xb4\xac1\x855\xb8I\x01\xeb\xb1\xf6\xb68'}],                            # noqa
            os.path.join(self.tmp_root_path, b'sample-folder/bar'): [{                                                      # noqa
                'type': git.GitType.TREE,                                                                                   # noqa
                'perms': git.GitPerm.TREE,                                                                                  # noqa
                'name': b'barfoo',                                                                                          # noqa
                'path': os.path.join(self.tmp_root_path, b'sample-folder/bar/barfoo'),                                      # noqa
                'sha1_git': b'\xc3\x02\x0fk\xf15\xa3\x8cm\xf3\xaf\xeb_\xb3\x822\xc5\xe0p\x87'}]}                            # noqa

        self.assertEquals(actual_walk1, expected_checksums)
    @istest
    def walk_and_compute_sha1_from_directory_without_root_tree(self):
        # compute the full checksums
        expected_hashes = git.walk_and_compute_sha1_from_directory(
            self.tmp_root_path)

        # except for the key on that round
        actual_hashes = git.walk_and_compute_sha1_from_directory(
            self.tmp_root_path,
            with_root_tree=False)

        # then, removing the root tree hash from the first round
        del expected_hashes[git.ROOT_TREE_KEY]

        # should give us the same checksums as the second round
        self.assertEquals(actual_hashes, expected_hashes)
class GitHashUpdate(GitHashWalkArborescenceTree):
    """Test `walk and git hash only on modified fs` functions.

    """
    @istest
    def update_checksums_from_add_new_file(self):
        # make a temporary arborescence tree to hash without ignoring anything
        # update the disk in some way (add a new file)
        # update the actual git checksums from the deeper tree modified

        # when
        objects = git.walk_and_compute_sha1_from_directory(
            self.tmp_root_path)

        # update the existing file
        changed_path = os.path.join(self.tmp_root_path,
                                    b'sample-folder/bar/barfoo/new')
        with open(changed_path, 'wb') as f:
            f.write(b'new line')

        # walk1 (this will be our expectation)
        expected_dict = git.walk_and_compute_sha1_from_directory(
            self.tmp_root_path)

        # then
        actual_dict = git.update_checksums_from(
            [{'path': changed_path, 'action': 'A'}],
            objects)

        self.assertEquals(expected_dict, actual_dict)

    @istest
    def update_checksums_from_modify_existing_file(self):
        # make a temporary arborescence tree to hash without ignoring anything
        # update the disk in some way ()
        # update the actual git checksums where only the modification is needed

        # when
        objects = git.walk_and_compute_sha1_from_directory(
            self.tmp_root_path)

        # update existing file
        changed_path = os.path.join(
            self.tmp_root_path,
            b'sample-folder/bar/barfoo/another-quote.org')
        with open(changed_path, 'wb+') as f:
            f.write(b'I have a dream')

        # walk1 (this will be our expectation)
        expected_dict = git.walk_and_compute_sha1_from_directory(
            self.tmp_root_path)

        # then
        actual_dict = git.update_checksums_from(
            [{'path': changed_path, 'action': 'M'}],
            objects)

        self.assertEquals(expected_dict, actual_dict)

    @istest
    def update_checksums_no_change(self):
        # when
        expected_dict = git.walk_and_compute_sha1_from_directory(
            self.tmp_root_path)

        # nothing changes on disk

        # then
        actual_dict = git.update_checksums_from([], expected_dict)

        self.assertEquals(actual_dict, expected_dict)

    def update_checksums_delete_existing_file(self):
        # make a temporary arborescence tree to hash without ignoring anything
        # update the disk in some way (delete a file)
        # update the actual git checksums from the deeper tree modified

        # when
        objects = git.walk_and_compute_sha1_from_directory(
            self.tmp_root_path)

        # Remove folder
        changed_path = os.path.join(self.tmp_root_path,
                                    b'sample-folder/bar/barfoo')
        shutil.rmtree(changed_path)

        # Actually walking the fs will be the resulting expectation
        expected_dict = git.walk_and_compute_sha1_from_directory(
            self.tmp_root_path)

        # then
        actual_dict = git.update_checksums_from(
            [{'path': changed_path, 'action': 'D'}],
            objects)

        self.assertEquals(actual_dict, expected_dict)
    def update_checksums_from_multiple_fs_modifications(self):
        # make a temporary arborescence tree to hash without ignoring anything
        # update the disk in some way (modify a file, add a new, delete one)
        # update the actual git checksums from the deeper tree modified

        # when
        objects = git.walk_and_compute_sha1_from_directory(
            self.tmp_root_path)

        # Actions on disk (imagine a checkout of some form)

        # 1. Create a new file
        changed_path = os.path.join(self.tmp_root_path,
                                    b'sample-folder/bar/barfoo/new')
        with open(changed_path, 'wb') as f:
            f.write(b'new line')

        # 2. update the existing file
        changed_path1 = os.path.join(
            self.tmp_root_path,
            b'sample-folder/bar/barfoo/another-quote.org')
        with open(changed_path1, 'wb') as f:
            f.write(b'new line')

        # 3. Remove some folder
        changed_path2 = os.path.join(self.tmp_root_path,
                                     b'sample-folder/foo')
        shutil.rmtree(changed_path2)

        # Actually walking the fs will be the resulting expectation
        expected_dict = git.walk_and_compute_sha1_from_directory(
            self.tmp_root_path)

        # then
        actual_dict = git.update_checksums_from(
            [{'path': changed_path, 'action': 'A'},
             {'path': changed_path1, 'action': 'M'},
             {'path': changed_path2, 'action': 'D'}],
            objects)

        self.assertEquals(expected_dict, actual_dict)

    @istest
    def update_checksums_from_common_ancestor(self):
        # when
        # Add some new arborescence below a folder destined to be removed
        # want to check that old keys does not remain
        future_folder_to_remove = os.path.join(self.tmp_root_path,
                                               b'sample-folder/bar/barfoo')

        # add .../barfoo/hello/world under (.../barfoo which will be destroyed)
        new_folder = os.path.join(future_folder_to_remove, b'hello')
        os.makedirs(new_folder, exist_ok=True)
        with open(os.path.join(future_folder_to_remove, b'world'), 'wb') as f:
            f.write(b"i'm sad 'cause i'm destined to be removed...")

        # now we scan the disk
        objects = git.walk_and_compute_sha1_from_directory(
            self.tmp_root_path)

        assert objects[future_folder_to_remove]

        # Actions on disk (to simulate a checkout of some sort)

        # 1. Create a new file
        changed_path = os.path.join(self.tmp_root_path,
                                    b'sample-folder/bar/barfoo/new')
        with open(changed_path, 'wb') as f:
            f.write(b'new line')

        # 2. update the existing file
        changed_path1 = os.path.join(
            self.tmp_root_path,
            b'sample-folder/bar/barfoo/another-quote.org')
        with open(changed_path1, 'wb') as f:
            f.write(b'new line')

        # 3. Remove folder
        shutil.rmtree(future_folder_to_remove)

        # Actually walking the fs will be the resulting expectation
        expected_dict = git.walk_and_compute_sha1_from_directory(
            self.tmp_root_path)

        # then
        actual_dict = git.update_checksums_from(
            [{'path': changed_path, 'action': 'A'},
             {'path': changed_path1, 'action': 'M'},
             {'path': future_folder_to_remove, 'action': 'D'}],
            objects)

        self.assertEquals(expected_dict, actual_dict)

    @istest
    def update_checksums_detects_recomputation_from_all_is_needed(self):
        # when
        objects = git.walk_and_compute_sha1_from_directory(
            self.tmp_root_path)

        # Actions on disk (imagine a checkout of some form)

        # 1. Create a new file
        changed_path = os.path.join(self.tmp_root_path,
                                    b'new-file-at-root')
        with open(changed_path, 'wb') as f:
            f.write(b'new line')

        # 2. update the existing file
        changed_path1 = os.path.join(
            self.tmp_root_path,
            b'sample-folder/bar/barfoo/another-quote.org')
        with open(changed_path1, 'wb') as f:
            f.write(b'new line')

        # 3. Remove some folder
        changed_path2 = os.path.join(self.tmp_root_path,
                                     b'sample-folder/foo')

        # 3. Remove some folder
        changed_path2 = os.path.join(self.tmp_root_path,
                                     b'sample-folder/bar/barfoo')
        shutil.rmtree(changed_path2)

        # Actually walking the fs will be the resulting expectation
        expected_dict = git.walk_and_compute_sha1_from_directory(
            self.tmp_root_path)

        # then
        actual_dict = git.update_checksums_from(
            [{'path': changed_path, 'action': 'A'},
             {'path': changed_path1, 'action': 'M'},
             {'path': changed_path2, 'action': 'D'}],
            objects)

        self.assertEquals(expected_dict, actual_dict)

    @istest
    def commonpath(self):
        paths = ['r/0/h',
                 'r/1/d', 'r/1/i/a', 'r/1/i/b', 'r/1/i/c',
                 'r/2/e', 'r/2/f', 'r/2/g']
        self.assertEquals(git.commonpath(paths), 'r')

        paths = ['r/1/d', 'r/1/i/a', 'r/1/i/b', 'r/1/i/c']
        self.assertEquals(git.commonpath(paths), 'r/1')

        paths = ['/a/r/2/g', '/a/r/1/i/c', '/a/r/0/h']
        self.assertEquals(git.commonpath(paths), '/a/r')

        paths = [b'/a/r/2/g', b'/b/r/1/i/c', b'/c/r/0/h']
        self.assertEquals(git.commonpath(paths), b'/')

        paths = ['a/z', 'a/z', 'a/z']
        self.assertEquals(git.commonpath(paths), 'a/z')

        paths = ['0']
        self.assertEquals(git.commonpath(paths), '0')


def untar(archive, dest):
    # cleanup
    shutil.rmtree(dest)
    os.mkdir(dest)
    # untar
    cmd = [b'tar', b'xf', archive, b'-C', dest]
    subprocess.check_output(cmd)


def ignore_svn_folder(dirpath):
    return b'.svn' not in dirpath


@attr('fs')
class GitHashUpdateRealUseCase(unittest.TestCase):
    """Test `walk and git hash only on modified fs` functions.

    """
    def setUp(self):
        self.tmp_root_path = tempfile.mkdtemp().encode('utf-8')

        archives_folder = os.path.join(
            os.path.dirname(__file__).encode('utf-8'),
            b'../../../..',
            b'swh-storage-testdata',
            b'svn-folders')

        self.pkg_doc_linux_r10 = os.path.join(archives_folder,
                                              b'pkg-doc-linux-r10.tgz')
        self.pkg_doc_linux_r11 = os.path.join(archives_folder,
                                              b'pkg-doc-linux-r11.tgz')
        self.pkg_doc_linux_r12 = os.path.join(archives_folder,
                                              b'pkg-doc-linux-r12.tgz')

    def tearDown(self):
        if os.path.exists(self.tmp_root_path):
            shutil.rmtree(self.tmp_root_path)

    @istest
    def use_case_1_r10_r11(self):
        # given
        # untar the svn revision 10
        untar(self.pkg_doc_linux_r10, self.tmp_root_path)

        objects_r10 = git.walk_and_compute_sha1_from_directory(
            self.tmp_root_path,
            ignore_svn_folder)

        # untar the svn revision 11
        untar(self.pkg_doc_linux_r11, self.tmp_root_path)

        objects_r11 = git.walk_and_compute_sha1_from_directory(
            self.tmp_root_path,
            ignore_svn_folder)

        assert objects_r10 != objects_r11

        changes = [
            {'action': 'D', 'path': os.path.join(self.tmp_root_path, b'copyrights/non-free/Kiosk')},         # noqa
            {'action': 'A', 'path': os.path.join(self.tmp_root_path, b'copyrights/undistributable/Kiosk')},  # noqa
            {'action': 'A', 'path': os.path.join(self.tmp_root_path, b'copyrights/undistributable')},        # noqa
            {'action': 'D', 'path': os.path.join(self.tmp_root_path, b'copyrights/non-free/UPS')},           # noqa
            {'action': 'A', 'path': os.path.join(self.tmp_root_path, b'copyrights/undistributable/UPS')}     # noqa
        ]

        # when
        # update from objects from previous revision (r10) with
        # actual changes from r10 to r11
        actual_objects = git.update_checksums_from(changes,
                                                   objects_r10,
                                                   ignore_svn_folder)

        # then
        self.assertEquals(actual_objects, objects_r11)

    @istest
    def use_case_2_r11_r12(self):
        # given
        # untar the svn revision 11
        untar(self.pkg_doc_linux_r11, self.tmp_root_path)

        objects_r11 = git.walk_and_compute_sha1_from_directory(
            self.tmp_root_path,
            ignore_svn_folder)

        # untar the svn revision 12
        untar(self.pkg_doc_linux_r12, self.tmp_root_path)

        objects_r12 = git.walk_and_compute_sha1_from_directory(
            self.tmp_root_path,
            ignore_svn_folder)

        assert objects_r11 != objects_r12
        changes = [
            {'action': 'A', 'path': os.path.join(self.tmp_root_path, b'trunk')},                                                # noqa
            {'action': 'D', 'path': os.path.join(self.tmp_root_path, b'copyrights')},                                           # noqa
            {'action': 'A', 'path': os.path.join(self.tmp_root_path, b'trunk/doc-linux/debian/copyright.head')},                # noqa
            {'action': 'A', 'path': os.path.join(self.tmp_root_path, b'trunk/doc-linux/debian/split-package')},                 # noqa
            {'action': 'A', 'path': os.path.join(self.tmp_root_path, b'trunk/doc-linux/debian/doc-base.faq')},                  # noqa
            {'action': 'A', 'path': os.path.join(self.tmp_root_path, b'trunk/doc-linux/debian/make-copyright')},                # noqa
            {'action': 'A', 'path': os.path.join(self.tmp_root_path, b'trunk/doc-linux/debian/doc-linux-html.menu')},           # noqa
            {'action': 'A', 'path': os.path.join(self.tmp_root_path, b'trunk/doc-linux/debian/redirect.patch')},                # noqa
            {'action': 'A', 'path': os.path.join(self.tmp_root_path, b'trunk/doc-linux/debian/doc-linux-html.overrides')},      # noqa
            {'action': 'A', 'path': os.path.join(self.tmp_root_path, b'trunk/doc-linux/debian/doc-linux-html.prerm')},          # noqa
            {'action': 'A', 'path': os.path.join(self.tmp_root_path, b'trunk/doc-linux/debian/README.updating')},               # noqa
            {'action': 'A', 'path': os.path.join(self.tmp_root_path, b'trunk/doc-linux/debian/doc-linux-html.preinst')},        # noqa
            {'action': 'A', 'path': os.path.join(self.tmp_root_path, b'trunk/doc-linux/debian/doc-linux-html.dirs')},           # noqa
            {'action': 'A', 'path': os.path.join(self.tmp_root_path, b'trunk/doc-linux/debian/changelog')},                     # noqa
            {'action': 'A', 'path': os.path.join(self.tmp_root_path, b'trunk/doc-linux/debian')},                               # noqa
            {'action': 'A', 'path': os.path.join(self.tmp_root_path, b'trunk/doc-linux/debian/doc-linux-text.README.Debian')},  # noqa
            {'action': 'A', 'path': os.path.join(self.tmp_root_path, b'trunk/doc-linux/debian/html2docs')},                     # noqa
            {'action': 'A', 'path': os.path.join(self.tmp_root_path, b'trunk/doc-linux/debian/rules')},                         # noqa
            {'action': 'A', 'path': os.path.join(self.tmp_root_path, b'trunk/doc-linux/debian/doc-linux-html.postrm')},         # noqa
            {'action': 'A', 'path': os.path.join(self.tmp_root_path, b'trunk/doc-linux')},                                      # noqa
            {'action': 'A', 'path': os.path.join(self.tmp_root_path, b'trunk/doc-linux/debian/make-omf')},                      # noqa
            {'action': 'A', 'path': os.path.join(self.tmp_root_path, b'trunk/doc-linux/debian/doc-linux-text.preinst')},        # noqa
            {'action': 'A', 'path': os.path.join(self.tmp_root_path, b'trunk/doc-linux/debian/doc-linux-html.postinst')},       # noqa
            {'action': 'A', 'path': os.path.join(self.tmp_root_path, b'trunk/doc-linux/debian/copyrights')},                    # noqa
            {'action': 'A', 'path': os.path.join(self.tmp_root_path, b'trunk/doc-linux/debian/control')},                       # noqa
            {'action': 'A', 'path': os.path.join(self.tmp_root_path, b'trunk/doc-linux/debian/doc-linux-text.dirs')},           # noqa
            {'action': 'A', 'path': os.path.join(self.tmp_root_path, b'trunk/doc-linux/debian/doc-linux-html.README.Debian')}   # noqa
        ]

        # when
        # update from objects from previous revision (r11) with
        # actual changes from r11 to r12
        actual_objects = git.update_checksums_from(changes,
                                                   objects_r11,
                                                   ignore_svn_folder)

        # then
        self.assertEquals(actual_objects, objects_r12)