/brz/remove-bazaar

# Copyright (C) 2008-2018 Jelmer Vernooij <jelmer@jelmer.uk>

# Copyright (C) 2007 Canonical Ltd

# Copyright (C) 2008 John Carr

#

# 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

"""Converters, etc for going between Bazaar and Git ids."""

import base64

import stat

from .. import (

    bencode,

    errors,

    foreign,

    trace,

    urlutils,

    )

from ..foreign import (

    ForeignVcs,

    VcsMappingRegistry,

    ForeignRevision,

    )

from ..revision import (

    NULL_REVISION,

    Revision,

    )

from .errors import (

    NoPushSupport,

    )

from .hg import (

    format_hg_metadata,

    extract_hg_metadata,

    )

from .roundtrip import (

    extract_bzr_metadata,

    inject_bzr_metadata,

    CommitSupplement,

    )

DEFAULT_FILE_MODE = stat.S_IFREG | 0o644

HG_RENAME_SOURCE = b"HG:rename-source"

HG_EXTRA = b"HG:extra"

# This HG extra is used to indicate the commit that this commit was based on.

HG_EXTRA_AMEND_SOURCE = b"amend_source"

FILE_ID_PREFIX = b'git:'

# Always the same.

ROOT_ID = b"TREE_ROOT"

class UnknownCommitExtra(errors.BzrError):

    _fmt = "Unknown extra fields in %(object)r: %(fields)r."

    def __init__(self, object, fields):

        errors.BzrError.__init__(self)

        self.object = object

        self.fields = ",".join(fields)

class UnknownMercurialCommitExtra(errors.BzrError):

    _fmt = "Unknown mercurial extra fields in %(object)r: %(fields)r."

    def __init__(self, object, fields):

        errors.BzrError.__init__(self)

        self.object = object

        self.fields = b",".join(fields)

def escape_file_id(file_id):

    file_id = file_id.replace(b'_', b'__')

    file_id = file_id.replace(b' ', b'_s')

    file_id = file_id.replace(b'\x0c', b'_c')

    return file_id

def unescape_file_id(file_id):

    ret = bytearray()

    i = 0

    while i < len(file_id):

        if file_id[i:i + 1] != b'_':

            ret.append(file_id[i])

        else:

            if file_id[i + 1:i + 2] == b'_':

                ret.append(b"_"[0])

            elif file_id[i + 1:i + 2] == b's':

                ret.append(b" "[0])

            elif file_id[i + 1:i + 2] == b'c':

                ret.append(b"\x0c"[0])

            else:

                raise ValueError("unknown escape character %s" %

                                 file_id[i + 1:i + 2])

            i += 1

        i += 1

    return bytes(ret)

def fix_person_identifier(text):

    if b"<" not in text and b">" not in text:

        username = text

        email = text

    elif b">" not in text:

        return text + b">"

    else:

        if text.rindex(b">") < text.rindex(b"<"):

            raise ValueError(text)

        username, email = text.split(b"<", 2)[-2:]

        email = email.split(b">", 1)[0]

        if username.endswith(b" "):

            username = username[:-1]

    return b"%s <%s>" % (username, email)

def decode_git_path(path):

    """Take a git path and decode it."""

    try:

        return path.decode('utf-8')

    except UnicodeDecodeError:

        if PY3:

            return path.decode('utf-8', 'surrogateescape')

        raise

def encode_git_path(path):

    """Take a regular path and encode it for git."""

    try:

        return path.encode('utf-8')

    except UnicodeEncodeError:

        if PY3:

            return path.encode('utf-8', 'surrogateescape')

        raise

def warn_escaped(commit, num_escaped):

    trace.warning("Escaped %d XML-invalid characters in %s. Will be unable "

                  "to regenerate the SHA map.", num_escaped, commit)

def warn_unusual_mode(commit, path, mode):

    trace.mutter("Unusual file mode %o for %s in %s. Storing as revision "

                 "property. ", mode, path, commit)

class BzrGitMapping(foreign.VcsMapping):

    """Class that maps between Git and Bazaar semantics."""

    experimental = False

    BZR_DUMMY_FILE = None  # type: Optional[str]

    def is_special_file(self, filename):

        return (filename in (self.BZR_DUMMY_FILE, ))

    def __init__(self):

        super(BzrGitMapping, self).__init__(foreign_vcs_git)

    def __eq__(self, other):

        return (type(self) == type(other)

                and self.revid_prefix == other.revid_prefix)

    @classmethod

    def revision_id_foreign_to_bzr(cls, git_rev_id):

        """Convert a git revision id handle to a Bazaar revision id."""

        from dulwich.protocol import ZERO_SHA

        if git_rev_id == ZERO_SHA:

            return NULL_REVISION

        return b"%s:%s" % (cls.revid_prefix, git_rev_id)

    @classmethod

    def revision_id_bzr_to_foreign(cls, bzr_rev_id):

        """Convert a Bazaar revision id to a git revision id handle."""

        if not bzr_rev_id.startswith(b"%s:" % cls.revid_prefix):

            raise errors.InvalidRevisionId(bzr_rev_id, cls)

        return bzr_rev_id[len(cls.revid_prefix) + 1:], cls()

    def generate_file_id(self, path):

        # Git paths are just bytestrings

        # We must just hope they are valid UTF-8..

        if isinstance(path, str):

            path = path.encode("utf-8")

        if path == b"":

            return ROOT_ID

        return FILE_ID_PREFIX + escape_file_id(path)

    def parse_file_id(self, file_id):

        if file_id == ROOT_ID:

            return u""

        if not file_id.startswith(FILE_ID_PREFIX):

            raise ValueError

        return decode_git_path(unescape_file_id(file_id[len(FILE_ID_PREFIX):]))

    def import_unusual_file_modes(self, rev, unusual_file_modes):

        if unusual_file_modes:

            ret = [(path, unusual_file_modes[path])

                   for path in sorted(unusual_file_modes.keys())]

            rev.properties[u'file-modes'] = bencode.bencode(ret)

    def export_unusual_file_modes(self, rev):

        try:

            file_modes = rev.properties[u'file-modes']

        except KeyError:

            return {}

        else:

            return dict(bencode.bdecode(file_modes.encode("utf-8")))

    def _generate_git_svn_metadata(self, rev, encoding):

        try:

            git_svn_id = rev.properties[u"git-svn-id"]

        except KeyError:

            return ""

        else:

            return "\ngit-svn-id: %s\n" % git_svn_id.encode(encoding)

    def _generate_hg_message_tail(self, rev):

        extra = {}

        renames = []

        branch = 'default'

        for name in rev.properties:

            if name == u'hg:extra:branch':

                branch = rev.properties[u'hg:extra:branch']

            elif name.startswith(u'hg:extra'):

                extra[name[len(u'hg:extra:'):]] = base64.b64decode(

                    rev.properties[name])

            elif name == u'hg:renames':

                renames = bencode.bdecode(base64.b64decode(

                    rev.properties[u'hg:renames']))

            # TODO: Export other properties as 'bzr:' extras?

        ret = format_hg_metadata(renames, branch, extra)

        if not isinstance(ret, bytes):

            raise TypeError(ret)

        return ret

    def _extract_git_svn_metadata(self, rev, message):

        lines = message.split("\n")

        if not (lines[-1] == "" and len(lines) >= 2 and

                lines[-2].startswith("git-svn-id:")):

            return message

        git_svn_id = lines[-2].split(": ", 1)[1]

        rev.properties[u'git-svn-id'] = git_svn_id

        (url, rev, uuid) = parse_git_svn_id(git_svn_id)

        # FIXME: Convert this to converted-from property somehow..

        return "\n".join(lines[:-2])

    def _extract_hg_metadata(self, rev, message):

        (message, renames, branch, extra) = extract_hg_metadata(message)

        if branch is not None:

            rev.properties[u'hg:extra:branch'] = branch

        for name, value in extra.items():

            rev.properties[u'hg:extra:' + name] = base64.b64encode(value)

        if renames:

            rev.properties[u'hg:renames'] = base64.b64encode(bencode.bencode(

                [(new, old) for (old, new) in renames.items()]))

        return message

    def _extract_bzr_metadata(self, rev, message):

        (message, metadata) = extract_bzr_metadata(message)

        return message, metadata

    def _decode_commit_message(self, rev, message, encoding):

        return message.decode(encoding), CommitSupplement()

    def _encode_commit_message(self, rev, message, encoding):

        return message.encode(encoding)

    def export_commit(self, rev, tree_sha, parent_lookup, lossy,

                      verifiers):

        """Turn a Bazaar revision in to a Git commit

        :param tree_sha: Tree sha for the commit

        :param parent_lookup: Function for looking up the GIT sha equiv of a

            bzr revision

        :param lossy: Whether to store roundtripping information.

        :param verifiers: Verifiers info

        :return dulwich.objects.Commit represent the revision:

        """

        from dulwich.objects import Commit, Tag

        commit = Commit()

        commit.tree = tree_sha

        if not lossy:

            metadata = CommitSupplement()

            metadata.verifiers = verifiers

        else:

            metadata = None

        parents = []

        for p in rev.parent_ids:

            try:

                git_p = parent_lookup(p)

            except KeyError:

                git_p = None

                if metadata is not None:

                    metadata.explicit_parent_ids = rev.parent_ids

            if git_p is not None:

                if len(git_p) != 40:

                    raise AssertionError("unexpected length for %r" % git_p)

                parents.append(git_p)

        commit.parents = parents

        try:

            encoding = rev.properties[u'git-explicit-encoding']

        except KeyError:

            encoding = rev.properties.get(u'git-implicit-encoding', 'utf-8')

        try:

            commit.encoding = rev.properties[u'git-explicit-encoding'].encode(

                'ascii')

        except KeyError:

            pass

        commit.committer = fix_person_identifier(rev.committer.encode(

            encoding))

        commit.author = fix_person_identifier(

            rev.get_apparent_authors()[0].encode(encoding))

        # TODO(jelmer): Don't use this hack.

        long = getattr(__builtins__, 'long', int)

        commit.commit_time = long(rev.timestamp)

        if u'author-timestamp' in rev.properties:

            commit.author_time = long(rev.properties[u'author-timestamp'])

        else:

            commit.author_time = commit.commit_time

        commit._commit_timezone_neg_utc = (

            u"commit-timezone-neg-utc" in rev.properties)

        commit.commit_timezone = rev.timezone

        commit._author_timezone_neg_utc = (

            u"author-timezone-neg-utc" in rev.properties)

        if u'author-timezone' in rev.properties:

            commit.author_timezone = int(rev.properties[u'author-timezone'])

        else:

            commit.author_timezone = commit.commit_timezone

        if u'git-gpg-signature' in rev.properties:

            commit.gpgsig = rev.properties[u'git-gpg-signature'].encode(

                'utf-8', 'surrogateescape')

        commit.message = self._encode_commit_message(rev, rev.message,

                                                     encoding)

        if not isinstance(commit.message, bytes):

            raise TypeError(commit.message)

        if metadata is not None:

            try:

                mapping_registry.parse_revision_id(rev.revision_id)

            except errors.InvalidRevisionId:

                metadata.revision_id = rev.revision_id

            mapping_properties = set(

                [u'author', u'author-timezone', u'author-timezone-neg-utc',

                 u'commit-timezone-neg-utc', u'git-implicit-encoding',

                 u'git-gpg-signature', u'git-explicit-encoding',

                 u'author-timestamp', u'file-modes'])

            for k, v in rev.properties.items():

                if k not in mapping_properties:

                    metadata.properties[k] = v

        if not lossy and metadata:

            if self.roundtripping:

                commit.message = inject_bzr_metadata(commit.message, metadata,

                                                     encoding)

            else:

                raise NoPushSupport(

                    None, None, self, revision_id=rev.revision_id)

        if not isinstance(commit.message, bytes):

            raise TypeError(commit.message)

        i = 0

        propname = u'git-mergetag-0'

        while propname in rev.properties:

            commit.mergetag.append(Tag.from_string(rev.properties[propname]))

            i += 1

            propname = u'git-mergetag-%d' % i

        if u'git-extra' in rev.properties:

            commit.extra.extend(

                [l.split(b' ', 1)

                 for l in rev.properties[u'git-extra'].splitlines()])

        return commit

    def get_revision_id(self, commit):

        if commit.encoding:

            encoding = commit.encoding.decode('ascii')

        else:

            encoding = 'utf-8'

        try:

            message, metadata = self._decode_commit_message(

                None, commit.message, encoding)

        except UnicodeDecodeError:

            pass

        else:

            if metadata.revision_id:

                return metadata.revision_id

        return self.revision_id_foreign_to_bzr(commit.id)

    def import_commit(self, commit, lookup_parent_revid, strict=True):

        """Convert a git commit to a bzr revision.

        :return: a `breezy.revision.Revision` object, foreign revid and a

            testament sha1

        """

        if commit is None:

            raise AssertionError("Commit object can't be None")

        rev = ForeignRevision(commit.id, self,

                              self.revision_id_foreign_to_bzr(commit.id))

        rev.git_metadata = None

        def decode_using_encoding(rev, commit, encoding):

            rev.committer = commit.committer.decode(encoding)

            if commit.committer != commit.author:

                rev.properties[u'author'] = commit.author.decode(encoding)

            rev.message, rev.git_metadata = self._decode_commit_message(

                rev, commit.message, encoding)

        if commit.encoding is not None:

            rev.properties[u'git-explicit-encoding'] = commit.encoding.decode(

                'ascii')

            decode_using_encoding(rev, commit, commit.encoding.decode('ascii'))

        else:

            for encoding in ('utf-8', 'latin1'):

                try:

                    decode_using_encoding(rev, commit, encoding)

                except UnicodeDecodeError:

                    pass

                else:

                    if encoding != 'utf-8':

                        rev.properties[u'git-implicit-encoding'] = encoding

                    break

        if commit.commit_time != commit.author_time:

            rev.properties[u'author-timestamp'] = str(commit.author_time)

        if commit.commit_timezone != commit.author_timezone:

            rev.properties[u'author-timezone'] = "%d" % commit.author_timezone

        if commit._author_timezone_neg_utc:

            rev.properties[u'author-timezone-neg-utc'] = ""

        if commit._commit_timezone_neg_utc:

            rev.properties[u'commit-timezone-neg-utc'] = ""

        if commit.gpgsig:

            rev.properties[u'git-gpg-signature'] = commit.gpgsig.decode(

                'utf-8', 'surrogateescape')

        if commit.mergetag:

            for i, tag in enumerate(commit.mergetag):

                rev.properties[u'git-mergetag-%d' % i] = tag.as_raw_string()

        rev.timestamp = commit.commit_time

        rev.timezone = commit.commit_timezone

        rev.parent_ids = None

        if rev.git_metadata is not None:

            md = rev.git_metadata

            roundtrip_revid = md.revision_id

            if md.explicit_parent_ids:

                rev.parent_ids = md.explicit_parent_ids

            rev.properties.update(md.properties)

            verifiers = md.verifiers

        else:

            roundtrip_revid = None

            verifiers = {}

        if rev.parent_ids is None:

            parents = []

            for p in commit.parents:

                try:

                    parents.append(lookup_parent_revid(p))

                except KeyError:

                    parents.append(self.revision_id_foreign_to_bzr(p))

            rev.parent_ids = list(parents)

        unknown_extra_fields = []

        extra_lines = []

        for k, v in commit.extra:

            if k == HG_RENAME_SOURCE:

                extra_lines.append(k + b' ' + v + b'\n')

            elif k == HG_EXTRA:

                hgk, hgv = v.split(b':', 1)

                if hgk not in (HG_EXTRA_AMEND_SOURCE, ) and strict:

                    raise UnknownMercurialCommitExtra(commit, [hgk])

                extra_lines.append(k + b' ' + v + b'\n')

            else:

                unknown_extra_fields.append(k)

        if unknown_extra_fields and strict:

            raise UnknownCommitExtra(

                commit,

                [f.decode('ascii', 'replace') for f in unknown_extra_fields])

        if extra_lines:

            rev.properties[u'git-extra'] = b''.join(extra_lines)

        return rev, roundtrip_revid, verifiers

class BzrGitMappingv1(BzrGitMapping):

    revid_prefix = b'git-v1'

    experimental = False

    def __str__(self):

        return self.revid_prefix

class BzrGitMappingExperimental(BzrGitMappingv1):

    revid_prefix = b'git-experimental'

    experimental = True

    roundtripping = False

    BZR_DUMMY_FILE = '.bzrdummy'

    def _decode_commit_message(self, rev, message, encoding):

        if rev is None:

            rev = Revision()

        message = self._extract_hg_metadata(rev, message)

        message = self._extract_git_svn_metadata(rev, message)

        message, metadata = self._extract_bzr_metadata(rev, message)

        return message.decode(encoding), metadata

    def _encode_commit_message(self, rev, message, encoding):

        ret = message.encode(encoding)

        ret += self._generate_hg_message_tail(rev)

        ret += self._generate_git_svn_metadata(rev, encoding)

        return ret

    def import_commit(self, commit, lookup_parent_revid, strict=True):

        rev, roundtrip_revid, verifiers = super(

            BzrGitMappingExperimental, self).import_commit(

                commit, lookup_parent_revid, strict)

        rev.properties[u'converted_revision'] = "git %s\n" % commit.id

        return rev, roundtrip_revid, verifiers

class GitMappingRegistry(VcsMappingRegistry):

    """Registry with available git mappings."""

    def revision_id_bzr_to_foreign(self, bzr_revid):

        if bzr_revid == NULL_REVISION:

            from dulwich.protocol import ZERO_SHA

            return ZERO_SHA, None

        if not bzr_revid.startswith(b"git-"):

            raise errors.InvalidRevisionId(bzr_revid, None)

        (mapping_version, git_sha) = bzr_revid.split(b":", 1)

        mapping = self.get(mapping_version)

        return mapping.revision_id_bzr_to_foreign(bzr_revid)

    parse_revision_id = revision_id_bzr_to_foreign

mapping_registry = GitMappingRegistry()

mapping_registry.register_lazy(b'git-v1', __name__,

                               "BzrGitMappingv1")

mapping_registry.register_lazy(b'git-experimental',

                               __name__, "BzrGitMappingExperimental")

# Uncomment the next line to enable the experimental bzr-git mappings.

# This will make sure all bzr metadata is pushed into git, allowing for

# full roundtripping later.

# NOTE: THIS IS EXPERIMENTAL. IT MAY EAT YOUR DATA OR CORRUPT

# YOUR BZR OR GIT REPOSITORIES. USE WITH CARE.

# mapping_registry.set_default('git-experimental')

mapping_registry.set_default(b'git-v1')