Andrew's git - gitweb.git/blob - contrib/hg-to-git/hg-to-git.py

   1#!/usr/bin/env python
   2
   3""" hg-to-git.py - A Mercurial to GIT converter
   4
   5    Copyright (C)2007 Stelian Pop <stelian@popies.net>
   6
   7    This program is free software; you can redistribute it and/or modify
   8    it under the terms of the GNU General Public License as published by
   9    the Free Software Foundation; either version 2, or (at your option)
  10    any later version.
  11
  12    This program is distributed in the hope that it will be useful,
  13    but WITHOUT ANY WARRANTY; without even the implied warranty of
  14    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15    GNU General Public License for more details.
  16
  17    You should have received a copy of the GNU General Public License
  18    along with this program; if not, see <http://www.gnu.org/licenses/>.
  19"""
  20
  21import os, os.path, sys
  22import tempfile, pickle, getopt
  23import re
  24
  25if sys.hexversion < 0x02030000:
  26   # The behavior of the pickle module changed significantly in 2.3
  27   sys.stderr.write("hg-to-git.py: requires Python 2.3 or later.\n")
  28   sys.exit(1)
  29
  30# Maps hg version -> git version
  31hgvers = {}
  32# List of children for each hg revision
  33hgchildren = {}
  34# List of parents for each hg revision
  35hgparents = {}
  36# Current branch for each hg revision
  37hgbranch = {}
  38# Number of new changesets converted from hg
  39hgnewcsets = 0
  40
  41#------------------------------------------------------------------------------
  42
  43def usage():
  44
  45        print """\
  46%s: [OPTIONS] <hgprj>
  47
  48options:
  49    -s, --gitstate=FILE: name of the state to be saved/read
  50                         for incrementals
  51    -n, --nrepack=INT:   number of changesets that will trigger
  52                         a repack (default=0, -1 to deactivate)
  53    -v, --verbose:       be verbose
  54
  55required:
  56    hgprj:  name of the HG project to import (directory)
  57""" % sys.argv[0]
  58
  59#------------------------------------------------------------------------------
  60
  61def getgitenv(user, date):
  62    env = ''
  63    elems = re.compile('(.*?)\s+<(.*)>').match(user)
  64    if elems:
  65        env += 'export GIT_AUTHOR_NAME="%s" ;' % elems.group(1)
  66        env += 'export GIT_COMMITTER_NAME="%s" ;' % elems.group(1)
  67        env += 'export GIT_AUTHOR_EMAIL="%s" ;' % elems.group(2)
  68        env += 'export GIT_COMMITTER_EMAIL="%s" ;' % elems.group(2)
  69    else:
  70        env += 'export GIT_AUTHOR_NAME="%s" ;' % user
  71        env += 'export GIT_COMMITTER_NAME="%s" ;' % user
  72        env += 'export GIT_AUTHOR_EMAIL= ;'
  73        env += 'export GIT_COMMITTER_EMAIL= ;'
  74
  75    env += 'export GIT_AUTHOR_DATE="%s" ;' % date
  76    env += 'export GIT_COMMITTER_DATE="%s" ;' % date
  77    return env
  78
  79#------------------------------------------------------------------------------
  80
  81state = ''
  82opt_nrepack = 0
  83verbose = False
  84
  85try:
  86    opts, args = getopt.getopt(sys.argv[1:], 's:t:n:v', ['gitstate=', 'tempdir=', 'nrepack=', 'verbose'])
  87    for o, a in opts:
  88        if o in ('-s', '--gitstate'):
  89            state = a
  90            state = os.path.abspath(state)
  91        if o in ('-n', '--nrepack'):
  92            opt_nrepack = int(a)
  93        if o in ('-v', '--verbose'):
  94            verbose = True
  95    if len(args) != 1:
  96        raise Exception('params')
  97except:
  98    usage()
  99    sys.exit(1)
 100
 101hgprj = args[0]
 102os.chdir(hgprj)
 103
 104if state:
 105    if os.path.exists(state):
 106        if verbose:
 107            print 'State does exist, reading'
 108        f = open(state, 'r')
 109        hgvers = pickle.load(f)
 110    else:
 111        print 'State does not exist, first run'
 112
 113sock = os.popen('hg tip --template "{rev}"')
 114tip = sock.read()
 115if sock.close():
 116    sys.exit(1)
 117if verbose:
 118    print 'tip is', tip
 119
 120# Calculate the branches
 121if verbose:
 122    print 'analysing the branches...'
 123hgchildren["0"] = ()
 124hgparents["0"] = (None, None)
 125hgbranch["0"] = "master"
 126for cset in range(1, int(tip) + 1):
 127    hgchildren[str(cset)] = ()
 128    prnts = os.popen('hg log -r %d --template "{parents}"' % cset).read().strip().split(' ')
 129    prnts = map(lambda x: x[:x.find(':')], prnts)
 130    if prnts[0] != '':
 131        parent = prnts[0].strip()
 132    else:
 133        parent = str(cset - 1)
 134    hgchildren[parent] += ( str(cset), )
 135    if len(prnts) > 1:
 136        mparent = prnts[1].strip()
 137        hgchildren[mparent] += ( str(cset), )
 138    else:
 139        mparent = None
 140
 141    hgparents[str(cset)] = (parent, mparent)
 142
 143    if mparent:
 144        # For merge changesets, take either one, preferably the 'master' branch
 145        if hgbranch[mparent] == 'master':
 146            hgbranch[str(cset)] = 'master'
 147        else:
 148            hgbranch[str(cset)] = hgbranch[parent]
 149    else:
 150        # Normal changesets
 151        # For first children, take the parent branch, for the others create a new branch
 152        if hgchildren[parent][0] == str(cset):
 153            hgbranch[str(cset)] = hgbranch[parent]
 154        else:
 155            hgbranch[str(cset)] = "branch-" + str(cset)
 156
 157if not hgvers.has_key("0"):
 158    print 'creating repository'
 159    os.system('git init')
 160
 161# loop through every hg changeset
 162for cset in range(int(tip) + 1):
 163
 164    # incremental, already seen
 165    if hgvers.has_key(str(cset)):
 166        continue
 167    hgnewcsets += 1
 168
 169    # get info
 170    log_data = os.popen('hg log -r %d --template "{tags}\n{date|date}\n{author}\n"' % cset).readlines()
 171    tag = log_data[0].strip()
 172    date = log_data[1].strip()
 173    user = log_data[2].strip()
 174    parent = hgparents[str(cset)][0]
 175    mparent = hgparents[str(cset)][1]
 176
 177    #get comment
 178    (fdcomment, filecomment) = tempfile.mkstemp()
 179    csetcomment = os.popen('hg log -r %d --template "{desc}"' % cset).read().strip()
 180    os.write(fdcomment, csetcomment)
 181    os.close(fdcomment)
 182
 183    print '-----------------------------------------'
 184    print 'cset:', cset
 185    print 'branch:', hgbranch[str(cset)]
 186    print 'user:', user
 187    print 'date:', date
 188    print 'comment:', csetcomment
 189    if parent:
 190        print 'parent:', parent
 191    if mparent:
 192        print 'mparent:', mparent
 193    if tag:
 194        print 'tag:', tag
 195    print '-----------------------------------------'
 196
 197    # checkout the parent if necessary
 198    if cset != 0:
 199        if hgbranch[str(cset)] == "branch-" + str(cset):
 200            print 'creating new branch', hgbranch[str(cset)]
 201            os.system('git checkout -b %s %s' % (hgbranch[str(cset)], hgvers[parent]))
 202        else:
 203            print 'checking out branch', hgbranch[str(cset)]
 204            os.system('git checkout %s' % hgbranch[str(cset)])
 205
 206    # merge
 207    if mparent:
 208        if hgbranch[parent] == hgbranch[str(cset)]:
 209            otherbranch = hgbranch[mparent]
 210        else:
 211            otherbranch = hgbranch[parent]
 212        print 'merging', otherbranch, 'into', hgbranch[str(cset)]
 213        os.system(getgitenv(user, date) + 'git merge --no-commit -s ours "" %s %s' % (hgbranch[str(cset)], otherbranch))
 214
 215    # remove everything except .git and .hg directories
 216    os.system('find . \( -path "./.hg" -o -path "./.git" \) -prune -o ! -name "." -print | xargs rm -rf')
 217
 218    # repopulate with checkouted files
 219    os.system('hg update -C %d' % cset)
 220
 221    # add new files
 222    os.system('git ls-files -x .hg --others | git update-index --add --stdin')
 223    # delete removed files
 224    os.system('git ls-files -x .hg --deleted | git update-index --remove --stdin')
 225
 226    # commit
 227    os.system(getgitenv(user, date) + 'git commit --allow-empty --allow-empty-message -a -F %s' % filecomment)
 228    os.unlink(filecomment)
 229
 230    # tag
 231    if tag and tag != 'tip':
 232        os.system(getgitenv(user, date) + 'git tag %s' % tag)
 233
 234    # delete branch if not used anymore...
 235    if mparent and len(hgchildren[str(cset)]):
 236        print "Deleting unused branch:", otherbranch
 237        os.system('git branch -d %s' % otherbranch)
 238
 239    # retrieve and record the version
 240    vvv = os.popen('git show --quiet --pretty=format:%H').read()
 241    print 'record', cset, '->', vvv
 242    hgvers[str(cset)] = vvv
 243
 244if hgnewcsets >= opt_nrepack and opt_nrepack != -1:
 245    os.system('git repack -a -d')
 246
 247# write the state for incrementals
 248if state:
 249    if verbose:
 250        print 'Writing state'
 251    f = open(state, 'w')
 252    pickle.dump(hgvers, f)
 253
 254# vim: et ts=8 sw=4 sts=4