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, write to the Free Software
  19    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  20"""
  21
  22import os, os.path, sys
  23import tempfile, pickle, getopt
  24import re
  25
  26# Maps hg version -> git version
  27hgvers = {}
  28# List of children for each hg revision
  29hgchildren = {}
  30# List of parents for each hg revision
  31hgparents = {}
  32# Current branch for each hg revision
  33hgbranch = {}
  34# Number of new changesets converted from hg
  35hgnewcsets = 0
  36
  37#------------------------------------------------------------------------------
  38
  39def usage():
  40
  41        print """\
  42%s: [OPTIONS] <hgprj>
  43
  44options:
  45    -s, --gitstate=FILE: name of the state to be saved/read
  46                         for incrementals
  47    -n, --nrepack=INT:   number of changesets that will trigger
  48                         a repack (default=0, -1 to deactivate)
  49    -v, --verbose:       be verbose
  50
  51required:
  52    hgprj:  name of the HG project to import (directory)
  53""" % sys.argv[0]
  54
  55#------------------------------------------------------------------------------
  56
  57def getgitenv(user, date):
  58    env = ''
  59    elems = re.compile('(.*?)\s+<(.*)>').match(user)
  60    if elems:
  61        env += 'export GIT_AUTHOR_NAME="%s" ;' % elems.group(1)
  62        env += 'export GIT_COMMITTER_NAME="%s" ;' % elems.group(1)
  63        env += 'export GIT_AUTHOR_EMAIL="%s" ;' % elems.group(2)
  64        env += 'export GIT_COMMITTER_EMAIL="%s" ;' % elems.group(2)
  65    else:
  66        env += 'export GIT_AUTHOR_NAME="%s" ;' % user
  67        env += 'export GIT_COMMITTER_NAME="%s" ;' % user
  68        env += 'export GIT_AUTHOR_EMAIL= ;'
  69        env += 'export GIT_COMMITTER_EMAIL= ;'
  70
  71    env += 'export GIT_AUTHOR_DATE="%s" ;' % date
  72    env += 'export GIT_COMMITTER_DATE="%s" ;' % date
  73    return env
  74
  75#------------------------------------------------------------------------------
  76
  77state = ''
  78opt_nrepack = 0
  79verbose = False
  80
  81try:
  82    opts, args = getopt.getopt(sys.argv[1:], 's:t:n:v', ['gitstate=', 'tempdir=', 'nrepack=', 'verbose'])
  83    for o, a in opts:
  84        if o in ('-s', '--gitstate'):
  85            state = a
  86            state = os.path.abspath(state)
  87        if o in ('-n', '--nrepack'):
  88            opt_nrepack = int(a)
  89        if o in ('-v', '--verbose'):
  90            verbose = True
  91    if len(args) != 1:
  92        raise Exception('params')
  93except:
  94    usage()
  95    sys.exit(1)
  96
  97hgprj = args[0]
  98os.chdir(hgprj)
  99
 100if state:
 101    if os.path.exists(state):
 102        if verbose:
 103            print 'State does exist, reading'
 104        f = open(state, 'r')
 105        hgvers = pickle.load(f)
 106    else:
 107        print 'State does not exist, first run'
 108
 109sock = os.popen('hg tip --template "{rev}"')
 110tip = sock.read()
 111if sock.close():
 112    sys.exit(1)
 113if verbose:
 114    print 'tip is', tip
 115
 116# Calculate the branches
 117if verbose:
 118    print 'analysing the branches...'
 119hgchildren["0"] = ()
 120hgparents["0"] = (None, None)
 121hgbranch["0"] = "master"
 122for cset in range(1, int(tip) + 1):
 123    hgchildren[str(cset)] = ()
 124    prnts = os.popen('hg log -r %d --template "{parents}"' % cset).read().strip().split(' ')
 125    prnts = map(lambda x: x[:x.find(':')], prnts)
 126    if prnts[0] != '':
 127        parent = prnts[0].strip()
 128    else:
 129        parent = str(cset - 1)
 130    hgchildren[parent] += ( str(cset), )
 131    if len(prnts) > 1:
 132        mparent = prnts[1].strip()
 133        hgchildren[mparent] += ( str(cset), )
 134    else:
 135        mparent = None
 136
 137    hgparents[str(cset)] = (parent, mparent)
 138
 139    if mparent:
 140        # For merge changesets, take either one, preferably the 'master' branch
 141        if hgbranch[mparent] == 'master':
 142            hgbranch[str(cset)] = 'master'
 143        else:
 144            hgbranch[str(cset)] = hgbranch[parent]
 145    else:
 146        # Normal changesets
 147        # For first children, take the parent branch, for the others create a new branch
 148        if hgchildren[parent][0] == str(cset):
 149            hgbranch[str(cset)] = hgbranch[parent]
 150        else:
 151            hgbranch[str(cset)] = "branch-" + str(cset)
 152
 153if not hgvers.has_key("0"):
 154    print 'creating repository'
 155    os.system('git init')
 156
 157# loop through every hg changeset
 158for cset in range(int(tip) + 1):
 159
 160    # incremental, already seen
 161    if hgvers.has_key(str(cset)):
 162        continue
 163    hgnewcsets += 1
 164
 165    # get info
 166    log_data = os.popen('hg log -r %d --template "{tags}\n{date|date}\n{author}\n"' % cset).readlines()
 167    tag = log_data[0].strip()
 168    date = log_data[1].strip()
 169    user = log_data[2].strip()
 170    parent = hgparents[str(cset)][0]
 171    mparent = hgparents[str(cset)][1]
 172
 173    #get comment
 174    (fdcomment, filecomment) = tempfile.mkstemp()
 175    csetcomment = os.popen('hg log -r %d --template "{desc}"' % cset).read().strip()
 176    os.write(fdcomment, csetcomment)
 177    os.close(fdcomment)
 178
 179    print '-----------------------------------------'
 180    print 'cset:', cset
 181    print 'branch:', hgbranch[str(cset)]
 182    print 'user:', user
 183    print 'date:', date
 184    print 'comment:', csetcomment
 185    if parent:
 186        print 'parent:', parent
 187    if mparent:
 188        print 'mparent:', mparent
 189    if tag:
 190        print 'tag:', tag
 191    print '-----------------------------------------'
 192
 193    # checkout the parent if necessary
 194    if cset != 0:
 195        if hgbranch[str(cset)] == "branch-" + str(cset):
 196            print 'creating new branch', hgbranch[str(cset)]
 197            os.system('git checkout -b %s %s' % (hgbranch[str(cset)], hgvers[parent]))
 198        else:
 199            print 'checking out branch', hgbranch[str(cset)]
 200            os.system('git checkout %s' % hgbranch[str(cset)])
 201
 202    # merge
 203    if mparent:
 204        if hgbranch[parent] == hgbranch[str(cset)]:
 205            otherbranch = hgbranch[mparent]
 206        else:
 207            otherbranch = hgbranch[parent]
 208        print 'merging', otherbranch, 'into', hgbranch[str(cset)]
 209        os.system(getgitenv(user, date) + 'git merge --no-commit -s ours "" %s %s' % (hgbranch[str(cset)], otherbranch))
 210
 211    # remove everything except .git and .hg directories
 212    os.system('find . \( -path "./.hg" -o -path "./.git" \) -prune -o ! -name "." -print | xargs rm -rf')
 213
 214    # repopulate with checkouted files
 215    os.system('hg update -C %d' % cset)
 216
 217    # add new files
 218    os.system('git ls-files -x .hg --others | git update-index --add --stdin')
 219    # delete removed files
 220    os.system('git ls-files -x .hg --deleted | git update-index --remove --stdin')
 221
 222    # commit
 223    os.system(getgitenv(user, date) + 'git commit --allow-empty -a -F %s' % filecomment)
 224    os.unlink(filecomment)
 225
 226    # tag
 227    if tag and tag != 'tip':
 228        os.system(getgitenv(user, date) + 'git tag %s' % tag)
 229
 230    # delete branch if not used anymore...
 231    if mparent and len(hgchildren[str(cset)]):
 232        print "Deleting unused branch:", otherbranch
 233        os.system('git branch -d %s' % otherbranch)
 234
 235    # retrieve and record the version
 236    vvv = os.popen('git show --quiet --pretty=format:%H').read()
 237    print 'record', cset, '->', vvv
 238    hgvers[str(cset)] = vvv
 239
 240if hgnewcsets >= opt_nrepack and opt_nrepack != -1:
 241    os.system('git repack -a -d')
 242
 243# write the state for incrementals
 244if state:
 245    if verbose:
 246        print 'Writing state'
 247    f = open(state, 'w')
 248    pickle.dump(hgvers, f)
 249
 250# vim: et ts=8 sw=4 sts=4