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

   1#! /usr/bin/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, popen2, 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
  50required:
  51    hgprj:  name of the HG project to import (directory)
  52""" % sys.argv[0]
  53
  54#------------------------------------------------------------------------------
  55
  56def getgitenv(user, date):
  57    env = ''
  58    elems = re.compile('(.*?)\s+<(.*)>').match(user)
  59    if elems:
  60        env += 'export GIT_AUTHOR_NAME="%s" ;' % elems.group(1)
  61        env += 'export GIT_COMMITER_NAME="%s" ;' % elems.group(1)
  62        env += 'export GIT_AUTHOR_EMAIL="%s" ;' % elems.group(2)
  63        env += 'export GIT_COMMITER_EMAIL="%s" ;' % elems.group(2)
  64    else:
  65        env += 'export GIT_AUTHOR_NAME="%s" ;' % user
  66        env += 'export GIT_COMMITER_NAME="%s" ;' % user
  67        env += 'export GIT_AUTHOR_EMAIL= ;'
  68        env += 'export GIT_COMMITER_EMAIL= ;'
  69
  70    env += 'export GIT_AUTHOR_DATE="%s" ;' % date
  71    env += 'export GIT_COMMITTER_DATE="%s" ;' % date
  72    return env
  73
  74#------------------------------------------------------------------------------
  75
  76state = ''
  77opt_nrepack = 0
  78
  79try:
  80    opts, args = getopt.getopt(sys.argv[1:], 's:t:n:', ['gitstate=', 'tempdir=', 'nrepack='])
  81    for o, a in opts:
  82        if o in ('-s', '--gitstate'):
  83            state = a
  84            state = os.path.abspath(state)
  85        if o in ('-n', '--nrepack'):
  86            opt_nrepack = int(a)
  87    if len(args) != 1:
  88        raise('params')
  89except:
  90    usage()
  91    sys.exit(1)
  92
  93hgprj = args[0]
  94os.chdir(hgprj)
  95
  96if state:
  97    if os.path.exists(state):
  98        print 'State does exist, reading'
  99        f = open(state, 'r')
 100        hgvers = pickle.load(f)
 101    else:
 102        print 'State does not exist, first run'
 103
 104tip = os.popen('hg tip --template "{rev}"').read()
 105print 'tip is', tip
 106
 107# Calculate the branches
 108print 'analysing the branches...'
 109hgchildren["0"] = ()
 110hgparents["0"] = (None, None)
 111hgbranch["0"] = "master"
 112for cset in range(1, int(tip) + 1):
 113    hgchildren[str(cset)] = ()
 114    prnts = os.popen('hg log -r %d --template "{parents}"' % cset).read().strip().split(' ')
 115    prnts = map(lambda x: x[:x.find(':')], prnts)
 116    if prnts[0] != '':
 117        parent = prnts[0].strip()
 118    else:
 119        parent = str(cset - 1)
 120    hgchildren[parent] += ( str(cset), )
 121    if len(prnts) > 1:
 122        mparent = prnts[1].strip()
 123        hgchildren[mparent] += ( str(cset), )
 124    else:
 125        mparent = None
 126
 127    hgparents[str(cset)] = (parent, mparent)
 128
 129    if mparent:
 130        # For merge changesets, take either one, preferably the 'master' branch
 131        if hgbranch[mparent] == 'master':
 132            hgbranch[str(cset)] = 'master'
 133        else:
 134            hgbranch[str(cset)] = hgbranch[parent]
 135    else:
 136        # Normal changesets
 137        # For first children, take the parent branch, for the others create a new branch
 138        if hgchildren[parent][0] == str(cset):
 139            hgbranch[str(cset)] = hgbranch[parent]
 140        else:
 141            hgbranch[str(cset)] = "branch-" + str(cset)
 142
 143if not hgvers.has_key("0"):
 144    print 'creating repository'
 145    os.system('git-init-db')
 146
 147# loop through every hg changeset
 148for cset in range(int(tip) + 1):
 149
 150    # incremental, already seen
 151    if hgvers.has_key(str(cset)):
 152        continue
 153    hgnewcsets += 1
 154
 155    # get info
 156    log_data = os.popen('hg log -r %d --template "{tags}\n{date|date}\n{author}\n"' % cset).readlines()
 157    tag = log_data[0].strip()
 158    date = log_data[1].strip()
 159    user = log_data[2].strip()
 160    parent = hgparents[str(cset)][0]
 161    mparent = hgparents[str(cset)][1]
 162
 163    #get comment
 164    (fdcomment, filecomment) = tempfile.mkstemp()
 165    csetcomment = os.popen('hg log -r %d --template "{desc}"' % cset).read().strip()
 166    os.write(fdcomment, csetcomment)
 167    os.close(fdcomment)
 168
 169    print '-----------------------------------------'
 170    print 'cset:', cset
 171    print 'branch:', hgbranch[str(cset)]
 172    print 'user:', user
 173    print 'date:', date
 174    print 'comment:', csetcomment
 175    if parent:
 176        print 'parent:', parent
 177    if mparent:
 178        print 'mparent:', mparent
 179    if tag:
 180        print 'tag:', tag
 181    print '-----------------------------------------'
 182
 183    # checkout the parent if necessary
 184    if cset != 0:
 185        if hgbranch[str(cset)] == "branch-" + str(cset):
 186            print 'creating new branch', hgbranch[str(cset)]
 187            os.system('git-checkout -b %s %s' % (hgbranch[str(cset)], hgvers[parent]))
 188        else:
 189            print 'checking out branch', hgbranch[str(cset)]
 190            os.system('git-checkout %s' % hgbranch[str(cset)])
 191
 192    # merge
 193    if mparent:
 194        if hgbranch[parent] == hgbranch[str(cset)]:
 195            otherbranch = hgbranch[mparent]
 196        else:
 197            otherbranch = hgbranch[parent]
 198        print 'merging', otherbranch, 'into', hgbranch[str(cset)]
 199        os.system(getgitenv(user, date) + 'git-merge --no-commit -s ours "" %s %s' % (hgbranch[str(cset)], otherbranch))
 200
 201    # remove everything except .git and .hg directories
 202    os.system('find . \( -path "./.hg" -o -path "./.git" \) -prune -o ! -name "." -print | xargs rm -rf')
 203
 204    # repopulate with checkouted files
 205    os.system('hg update -C %d' % cset)
 206
 207    # add new files
 208    os.system('git-ls-files -x .hg --others | git-update-index --add --stdin')
 209    # delete removed files
 210    os.system('git-ls-files -x .hg --deleted | git-update-index --remove --stdin')
 211
 212    # commit
 213    os.system(getgitenv(user, date) + 'git commit --allow-empty -a -F %s' % filecomment)
 214    os.unlink(filecomment)
 215
 216    # tag
 217    if tag and tag != 'tip':
 218        os.system(getgitenv(user, date) + 'git-tag %s' % tag)
 219
 220    # delete branch if not used anymore...
 221    if mparent and len(hgchildren[str(cset)]):
 222        print "Deleting unused branch:", otherbranch
 223        os.system('git-branch -d %s' % otherbranch)
 224
 225    # retrieve and record the version
 226    vvv = os.popen('git-show --quiet --pretty=format:%H').read()
 227    print 'record', cset, '->', vvv
 228    hgvers[str(cset)] = vvv
 229
 230if hgnewcsets >= opt_nrepack and opt_nrepack != -1:
 231    os.system('git-repack -a -d')
 232
 233# write the state for incrementals
 234if state:
 235    print 'Writing state'
 236    f = open(state, 'w')
 237    pickle.dump(hgvers, f)
 238
 239# vim: et ts=8 sw=4 sts=4