git: skeleton of a new extension to _directly_ operate on git repos
This is based in part of work I did years ago in hgit, but it's mostly
new code since I'm using pygit2 instead of dulwich and the hg storage
interfaces have improved. Some cleanup of old hgit code by Pulkit,
which I greatly appreciate.
test-git-interop.t does not cover a whole lot of cases, but it
passes. It includes status, diff, making a new commit, and `hg annotate`
working on the git repository.
This is _not_ (yet) production quality code: this is an
experiment. Known technical debt lurking in this implementation:
* Writing bookmarks just totally ignores transactions.
* The way progress is threaded down into the gitstore is awful.
* Ideally we'd find a way to incrementally reindex DAGs. I'm not sure
how to do that efficiently, so we might need a "known only fast-forwards"
mode on the DAG indexer for use on `hg commit` and friends.
* We don't even _try_ to do anything reasonable for `hg pull` or `hg push`.
* Mercurial need an interface for the changelog type.
Tests currently require git 2.24 as far as I'm aware: `git status` has
some changed output that I didn't try and handle in a compatible way.
This patch has produced some interesting cleanups, most recently on
the manifest type. I expect continuing down this road will produce
other meritorious cleanups throughout our code.
Differential Revision: https://phab.mercurial-scm.org/D6734
# darcs.py - darcs support for the convert extension
#
# Copyright 2007-2009 Matt Mackall <mpm@selenic.com> and others
#
# This software may be used and distributed according to the terms of the
# GNU General Public License version 2 or any later version.
from __future__ import absolute_import
import errno
import os
import re
import shutil
from mercurial.i18n import _
from mercurial import (
error,
pycompat,
util,
)
from mercurial.utils import dateutil
from . import common
NoRepo = common.NoRepo
# The naming drift of ElementTree is fun!
try:
import xml.etree.cElementTree.ElementTree as ElementTree
import xml.etree.cElementTree.XMLParser as XMLParser
except ImportError:
try:
import xml.etree.ElementTree.ElementTree as ElementTree
import xml.etree.ElementTree.XMLParser as XMLParser
except ImportError:
try:
import elementtree.cElementTree.ElementTree as ElementTree
import elementtree.cElementTree.XMLParser as XMLParser
except ImportError:
try:
import elementtree.ElementTree.ElementTree as ElementTree
import elementtree.ElementTree.XMLParser as XMLParser
except ImportError:
pass
class darcs_source(common.converter_source, common.commandline):
def __init__(self, ui, repotype, path, revs=None):
common.converter_source.__init__(self, ui, repotype, path, revs=revs)
common.commandline.__init__(self, ui, b'darcs')
# check for _darcs, ElementTree so that we can easily skip
# test-convert-darcs if ElementTree is not around
if not os.path.exists(os.path.join(path, b'_darcs')):
raise NoRepo(_(b"%s does not look like a darcs repository") % path)
common.checktool(b'darcs')
version = self.run0(b'--version').splitlines()[0].strip()
if version < b'2.1':
raise error.Abort(
_(b'darcs version 2.1 or newer needed (found %r)') % version
)
if b"ElementTree" not in globals():
raise error.Abort(_(b"Python ElementTree module is not available"))
self.path = os.path.realpath(path)
self.lastrev = None
self.changes = {}
self.parents = {}
self.tags = {}
# Check darcs repository format
format = self.format()
if format:
if format in (b'darcs-1.0', b'hashed'):
raise NoRepo(
_(
b"%s repository format is unsupported, "
b"please upgrade"
)
% format
)
else:
self.ui.warn(_(b'failed to detect repository format!'))
def before(self):
self.tmppath = pycompat.mkdtemp(
prefix=b'convert-' + os.path.basename(self.path) + b'-'
)
output, status = self.run(b'init', repodir=self.tmppath)
self.checkexit(status)
tree = self.xml(
b'changes', xml_output=True, summary=True, repodir=self.path
)
tagname = None
child = None
for elt in tree.findall(b'patch'):
node = elt.get(b'hash')
name = elt.findtext(b'name', b'')
if name.startswith(b'TAG '):
tagname = name[4:].strip()
elif tagname is not None:
self.tags[tagname] = node
tagname = None
self.changes[node] = elt
self.parents[child] = [node]
child = node
self.parents[child] = []
def after(self):
self.ui.debug(b'cleaning up %s\n' % self.tmppath)
shutil.rmtree(self.tmppath, ignore_errors=True)
def recode(self, s, encoding=None):
if isinstance(s, pycompat.unicode):
# XMLParser returns unicode objects for anything it can't
# encode into ASCII. We convert them back to str to get
# recode's normal conversion behavior.
s = s.encode('latin-1')
return super(darcs_source, self).recode(s, encoding)
def xml(self, cmd, **kwargs):
# NOTE: darcs is currently encoding agnostic and will print
# patch metadata byte-for-byte, even in the XML changelog.
etree = ElementTree()
# While we are decoding the XML as latin-1 to be as liberal as
# possible, etree will still raise an exception if any
# non-printable characters are in the XML changelog.
parser = XMLParser(encoding=b'latin-1')
p = self._run(cmd, **kwargs)
etree.parse(p.stdout, parser=parser)
p.wait()
self.checkexit(p.returncode)
return etree.getroot()
def format(self):
output, status = self.run(b'show', b'repo', repodir=self.path)
self.checkexit(status)
m = re.search(r'^\s*Format:\s*(.*)$', output, re.MULTILINE)
if not m:
return None
return b','.join(sorted(f.strip() for f in m.group(1).split(b',')))
def manifest(self):
man = []
output, status = self.run(
b'show', b'files', no_directories=True, repodir=self.tmppath
)
self.checkexit(status)
for line in output.split(b'\n'):
path = line[2:]
if path:
man.append(path)
return man
def getheads(self):
return self.parents[None]
def getcommit(self, rev):
elt = self.changes[rev]
dateformat = b'%a %b %d %H:%M:%S %Z %Y'
date = dateutil.strdate(elt.get(b'local_date'), dateformat)
desc = elt.findtext(b'name') + b'\n' + elt.findtext(b'comment', b'')
# etree can return unicode objects for name, comment, and author,
# so recode() is used to ensure str objects are emitted.
newdateformat = b'%Y-%m-%d %H:%M:%S %1%2'
return common.commit(
author=self.recode(elt.get(b'author')),
date=dateutil.datestr(date, newdateformat),
desc=self.recode(desc).strip(),
parents=self.parents[rev],
)
def pull(self, rev):
output, status = self.run(
b'pull',
self.path,
all=True,
match=b'hash %s' % rev,
no_test=True,
no_posthook=True,
external_merge=b'/bin/false',
repodir=self.tmppath,
)
if status:
if output.find(b'We have conflicts in') == -1:
self.checkexit(status, output)
output, status = self.run(b'revert', all=True, repodir=self.tmppath)
self.checkexit(status, output)
def getchanges(self, rev, full):
if full:
raise error.Abort(_(b"convert from darcs does not support --full"))
copies = {}
changes = []
man = None
for elt in self.changes[rev].find(b'summary').getchildren():
if elt.tag in (b'add_directory', b'remove_directory'):
continue
if elt.tag == b'move':
if man is None:
man = self.manifest()
source, dest = elt.get(b'from'), elt.get(b'to')
if source in man:
# File move
changes.append((source, rev))
changes.append((dest, rev))
copies[dest] = source
else:
# Directory move, deduce file moves from manifest
source = source + b'/'
for f in man:
if not f.startswith(source):
continue
fdest = dest + b'/' + f[len(source) :]
changes.append((f, rev))
changes.append((fdest, rev))
copies[fdest] = f
else:
changes.append((elt.text.strip(), rev))
self.pull(rev)
self.lastrev = rev
return sorted(changes), copies, set()
def getfile(self, name, rev):
if rev != self.lastrev:
raise error.Abort(_(b'internal calling inconsistency'))
path = os.path.join(self.tmppath, name)
try:
data = util.readfile(path)
mode = os.lstat(path).st_mode
except IOError as inst:
if inst.errno == errno.ENOENT:
return None, None
raise
mode = (mode & 0o111) and b'x' or b''
return data, mode
def gettags(self):
return self.tags