contrib/hg-to-git/hg-to-git.py

   1 #! /usr/bin/python
   2
   3 """ hg-to-svn.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
  22 import os, os.path, sys
  23 import tempfile, popen2, pickle, getopt
  24 import re
  25
  26 # Maps hg version -> git version
  27 hgvers = {}
  28 # List of children for each hg revision
  29 hgchildren = {}
  30 # Current branch for each hg revision
  31 hgbranch = {}
  32 # Number of new changesets converted from hg
  33 hgnewcsets = 0
  34
  35 #------------------------------------------------------------------------------
  36
  37 def usage():
  38
  39         print """\
  40 %s: [OPTIONS] <hgprj>
  41
  42 options:
  43     -s, --gitstate=FILE: name of the state to be saved/read
  44                          for incrementals
  45     -n, --nrepack=INT:   number of changesets that will trigger
  46                          a repack (default=0, -1 to deactivate)
  47
  48 required:
  49     hgprj:  name of the HG project to import (directory)
  50 """ % sys.argv[0]
  51
  52 #------------------------------------------------------------------------------
  53
  54 def getgitenv(user, date):
  55     env = ''
  56     elems = re.compile('(.*?)\s+<(.*)>').match(user)
  57     if elems:
  58         env += 'export GIT_AUTHOR_NAME="%s" ;' % elems.group(1)
  59         env += 'export GIT_COMMITER_NAME="%s" ;' % elems.group(1)
  60         env += 'export GIT_AUTHOR_EMAIL="%s" ;' % elems.group(2)
  61         env += 'export GIT_COMMITER_EMAIL="%s" ;' % elems.group(2)
  62     else:
  63         env += 'export GIT_AUTHOR_NAME="%s" ;' % user
  64         env += 'export GIT_COMMITER_NAME="%s" ;' % user
  65         env += 'export GIT_AUTHOR_EMAIL= ;'
  66         env += 'export GIT_COMMITER_EMAIL= ;'
  67
  68     env += 'export GIT_AUTHOR_DATE="%s" ;' % date
  69     env += 'export GIT_COMMITTER_DATE="%s" ;' % date
  70     return env
  71
  72 #------------------------------------------------------------------------------
  73
  74 state = ''
  75 opt_nrepack = 0
  76
  77 try:
  78     opts, args = getopt.getopt(sys.argv[1:], 's:t:n:', ['gitstate=', 'tempdir=', 'nrepack='])
  79     for o, a in opts:
  80         if o in ('-s', '--gitstate'):
  81             state = a
  82             state = os.path.abspath(state)
  83         if o in ('-n', '--nrepack'):
  84             opt_nrepack = int(a)
  85     if len(args) != 1:
  86         raise('params')
  87 except:
  88     usage()
  89     sys.exit(1)
  90
  91 hgprj = args[0]
  92 os.chdir(hgprj)
  93
  94 if state:
  95     if os.path.exists(state):
  96         print 'State does exist, reading'
  97         f = open(state, 'r')
  98         hgvers = pickle.load(f)
  99     else:
 100         print 'State does not exist, first run'
 101
 102 tip = os.popen('hg tip | head -1 | cut -f 2 -d :').read().strip()
 103 print 'tip is', tip
 104
 105 # Calculate the branches
 106 print 'analysing the branches...'
 107 hgchildren["0"] = ()
 108 hgbranch["0"] = "master"
 109 for cset in range(1, int(tip) + 1):
 110     hgchildren[str(cset)] = ()
 111     prnts = os.popen('hg log -r %d | grep ^parent: | cut -f 2 -d :' % cset).readlines()
 112     if len(prnts) > 0:
 113         parent = prnts[0].strip()
 114     else:
 115         parent = str(cset - 1)
 116     hgchildren[parent] += ( str(cset), )
 117     if len(prnts) > 1:
 118         mparent = prnts[1].strip()
 119         hgchildren[mparent] += ( str(cset), )
 120     else:
 121         mparent = None
 122
 123     if mparent:
 124         # For merge changesets, take either one, preferably the 'master' branch
 125         if hgbranch[mparent] == 'master':
 126             hgbranch[str(cset)] = 'master'
 127         else:
 128             hgbranch[str(cset)] = hgbranch[parent]
 129     else:
 130         # Normal changesets
 131         # For first children, take the parent branch, for the others create a new branch
 132         if hgchildren[parent][0] == str(cset):
 133             hgbranch[str(cset)] = hgbranch[parent]
 134         else:
 135             hgbranch[str(cset)] = "branch-" + str(cset)
 136
 137 if not hgvers.has_key("0"):
 138     print 'creating repository'
 139     os.system('git-init-db')
 140
 141 # loop through every hg changeset
 142 for cset in range(int(tip) + 1):
 143
 144     # incremental, already seen
 145     if hgvers.has_key(str(cset)):
 146         continue
 147     hgnewcsets += 1
 148
 149     # get info
 150     prnts = os.popen('hg log -r %d | grep ^parent: | cut -f 2 -d :' % cset).readlines()
 151     if len(prnts) > 0:
 152         parent = prnts[0].strip()
 153     else:
 154         parent = str(cset - 1)
 155     if len(prnts) > 1:
 156         mparent = prnts[1].strip()
 157     else:
 158         mparent = None
 159
 160     (fdcomment, filecomment) = tempfile.mkstemp()
 161     csetcomment = os.popen('hg log -r %d -v | grep -v ^changeset: | grep -v ^parent: | grep -v ^user: | grep -v ^date | grep -v ^files: | grep -v ^description: | grep -v ^tag:' % cset).read().strip()
 162     os.write(fdcomment, csetcomment)
 163     os.close(fdcomment)
 164
 165     date = os.popen('hg log -r %d | grep ^date: | cut -f 2- -d :' % cset).read().strip()
 166
 167     tag = os.popen('hg log -r %d | grep ^tag: | cut -f 2- -d :' % cset).read().strip()
 168
 169     user = os.popen('hg log -r %d | grep ^user: | cut -f 2- -d :' % cset).read().strip()
 170
 171     print '-----------------------------------------'
 172     print 'cset:', cset
 173     print 'branch:', hgbranch[str(cset)]
 174     print 'user:', user
 175     print 'date:', date
 176     print 'comment:', csetcomment
 177     print 'parent:', parent
 178     if mparent:
 179         print 'mparent:', mparent
 180     if tag:
 181         print 'tag:', tag
 182     print '-----------------------------------------'
 183
 184     # checkout the parent if necessary
 185     if cset != 0:
 186         if hgbranch[str(cset)] == "branch-" + str(cset):
 187             print 'creating new branch', hgbranch[str(cset)]
 188             os.system('git-checkout -b %s %s' % (hgbranch[str(cset)], hgvers[parent]))
 189         else:
 190             print 'checking out branch', hgbranch[str(cset)]
 191             os.system('git-checkout %s' % hgbranch[str(cset)])
 192
 193     # merge
 194     if mparent:
 195         if hgbranch[parent] == hgbranch[str(cset)]:
 196             otherbranch = hgbranch[mparent]
 197         else:
 198             otherbranch = hgbranch[parent]
 199         print 'merging', otherbranch, 'into', hgbranch[str(cset)]
 200         os.system(getgitenv(user, date) + 'git-merge --no-commit -s ours "" %s %s' % (hgbranch[str(cset)], otherbranch))
 201
 202     # remove everything except .git and .hg directories
 203     os.system('find . \( -path "./.hg" -o -path "./.git" \) -prune -o ! -name "." -print | xargs rm -rf')
 204
 205     # repopulate with checkouted files
 206     os.system('hg update -C %d' % cset)
 207
 208     # add new files
 209     os.system('git-ls-files -x .hg --others | git-update-index --add --stdin')
 210     # delete removed files
 211     os.system('git-ls-files -x .hg --deleted | git-update-index --remove --stdin')
 212
 213     # commit
 214     os.system(getgitenv(user, date) + 'git commit --allow-empty -a -F %s' % filecomment)
 215     os.unlink(filecomment)
 216
 217     # tag
 218     if tag and tag != 'tip':
 219         os.system(getgitenv(user, date) + 'git-tag %s' % tag)
 220
 221     # delete branch if not used anymore...
 222     if mparent and len(hgchildren[str(cset)]):
 223         print "Deleting unused branch:", otherbranch
 224         os.system('git-branch -d %s' % otherbranch)
 225
 226     # retrieve and record the version
 227     vvv = os.popen('git-show | head -1').read()
 228     vvv = vvv[vvv.index(' ') + 1 : ].strip()
 229     print 'record', cset, '->', vvv
 230     hgvers[str(cset)] = vvv
 231
 232 if hgnewcsets >= opt_nrepack and opt_nrepack != -1:
 233     os.system('git-repack -a -d')
 234
 235 # write the state for incrementals
 236 if state:
 237     print 'Writing state'
 238     f = open(state, 'w')
 239     pickle.dump(hgvers, f)
 240
 241 # vim: et ts=8 sw=4 sts=4