[PATCH] Add hg-to-git conversion utility.
- From
Stelian Pop <stelian@popies.net>
- Date
- Jan 12, 2007, 21:57 UTC
- Message-ID
- <1168639023.13640.2.camel@localhost.localdomain>
- In-Reply-To
- <1168632860.29218.5.camel@voyager.dsnet>
hg-to-git.py is able to convert a Mercurial repository into a git one, and preserves the branches in the process (unlike tailor)
hg-to-git.py can probably be greatly improved (it's a rather crude combination of shell and python) but it does already work quite well for me. Features: - supports incremental conversion (for keeping a git repo in sync with a hg one) - supports hg branches - converts hg tags
Signed-off-by: Stelian Pop <stelian@popies.net> --- Documentation/git-tools.txt | 7 + contrib/hg-to-git/hg-to-git.py | 233 +++++++++++++++++++++++++++++++++++++++ contrib/hg-to-git/hg-to-git.txt | 22 ++++ 3 files changed, 262 insertions(+), 0 deletions(-)
diff --git a/Documentation/git-tools.txt b/Documentation/git-tools.txt index 0914cbb..4d245d5 100644 --- a/Documentation/git-tools.txt +++ b/Documentation/git-tools.txt @@ -68,6 +68,13 @@ History Viewers Foreign SCM interface --------------------- + - *hg-to-git* (contrib/) + + hg-to-git converts a Mercurial repository into a git one, and + preserves the full branch history in the process. hg-to-git can + also be used in an incremental way to keep the git repository + in sync with the master Mercurial repository. + - *git-svn* (contrib/) git-svn is a simple conduit for changesets between a single Subversion diff --git a/contrib/hg-to-git/hg-to-git.py b/contrib/hg-to-git/hg-to-git.py new file mode 100755 index 0000000..37337ff --- /dev/null +++ b/contrib/hg-to-git/hg-to-git.py @@ -0,0 +1,233 @@ +#! /usr/bin/python + +""" hg-to-svn.py - A Mercurial to GIT converter + + Copyright (C)2007 Stelian Pop <stelian@popies.net> + + This program is free software; you can redistribute it and/or modify + it under the terms of the GNU General Public License as published by + the Free Software Foundation; either version 2, or (at your option) + any later version. + + This program is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + GNU General Public License for more details. + + You should have received a copy of the GNU General Public License + along with this program; if not, write to the Free Software + Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. +""" + +import os, os.path, sys +import tempfile, popen2, pickle, getopt +import re + +# Maps hg version -> git version +hgvers = {} +# List of children for each hg revision +hgchildren = {} +# Current branch for each hg revision +hgbranch = {} + +#------------------------------------------------------------------------------ + +def usage(): + + print """\ +%s: [OPTIONS] <hgprj> + +options: + -s, --gitstate=FILE: name of the state to be saved/read + for incrementals + +required: + hgprj: name of the HG project to import (directory) +""" % sys.argv[0] + +#------------------------------------------------------------------------------ + +def getgitenv(user, date): + env = '' + elems = re.compile('(.*?)\s+<(.*)>').match(user) + if elems: + env += 'export GIT_AUTHOR_NAME="%s" ;' % elems.group(1) + env += 'export GIT_COMMITER_NAME="%s" ;' % elems.group(1) + env += 'export GIT_AUTHOR_EMAIL="%s" ;' % elems.group(2) + env += 'export GIT_COMMITER_EMAIL="%s" ;' % elems.group(2) + else: + env += 'export GIT_AUTHOR_NAME="%s" ;' % user + env += 'export GIT_COMMITER_NAME="%s" ;' % user + env += 'export GIT_AUTHOR_EMAIL= ;' + env += 'export GIT_COMMITER_EMAIL= ;' + + env += 'export GIT_AUTHOR_DATE="%s" ;' % date + env += 'export GIT_COMMITTER_DATE="%s" ;' % date + return env + +#------------------------------------------------------------------------------ + +state = '' + +try: + opts, args = getopt.getopt(sys.argv[1:], 's:t:', ['gitstate=', 'tempdir=']) + for o, a in opts: + if o in ('-s', '--gitstate'): + state = a + state = os.path.abspath(state) + + if len(args) != 1: + raise('params') +except: + usage() + sys.exit(1) + +hgprj = args[0] +os.chdir(hgprj) + +if state: + if os.path.exists(state): + print 'State does exist, reading' + f = open(state, 'r') + hgvers = pickle.load(f) + else: + print 'State does not exist, first run' + +tip = os.popen('hg tip | head -1 | cut -f 2 -d :').read().strip() +print 'tip is', tip + +# Calculate the branches +print 'analysing the branches...' +hgchildren["0"] = () +hgbranch["0"] = "master" +for cset in range(1, int(tip) + 1): + hgchildren[str(cset)] = () + prnts = os.popen('hg log -r %d | grep ^parent: | cut -f 2 -d :' % cset).readlines() + if len(prnts) > 0: + parent = prnts[0].strip() + else: + parent = str(cset - 1) + hgchildren[parent] += ( str(cset), ) + if len(prnts) > 1: + mparent = prnts[1].strip() + hgchildren[mparent] += ( str(cset), ) + else: + mparent = None + + if mparent: + # For merge changesets, take either one, preferably the 'master' branch + if hgbranch[mparent] == 'master': + hgbranch[str(cset)] = 'master' + else: + hgbranch[str(cset)] = hgbranch[parent] + else: + # Normal changesets + # For first children, take the parent branch, for the others create a new branch + if hgchildren[parent][0] == str(cset): + hgbranch[str(cset)] = hgbranch[parent] + else: + hgbranch[str(cset)] = "branch-" + str(cset) + +if not hgvers.has_key("0"): + print 'creating repository' + os.system('git-init-db') + +# loop through every hg changeset +for cset in range(int(tip) + 1): + + # incremental, already seen + if hgvers.has_key(str(cset)): + continue + + # get info + prnts = os.popen('hg log -r %d | grep ^parent: | cut -f 2 -d :' % cset).readlines() + if len(prnts) > 0: + parent = prnts[0].strip() + else: + parent = str(cset - 1) + if len(prnts) > 1: + mparent = prnts[1].strip() + else: + mparent = None + + (fdcomment, filecomment) = tempfile.mkstemp() + 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() + os.write(fdcomment, csetcomment) + os.close(fdcomment) + + date = os.popen('hg log -r %d | grep ^date: | cut -f 2- -d :' % cset).read().strip() + + tag = os.popen('hg log -r %d | grep ^tag: | cut -f 2- -d :' % cset).read().strip() + + user = os.popen('hg log -r %d | grep ^user: | cut -f 2- -d :' % cset).read().strip() + + print '-----------------------------------------' + print 'cset:', cset + print 'branch:', hgbranch[str(cset)] + print 'user:', user + print 'date:', date + print 'comment:', csetcomment + print 'parent:', parent + if mparent: + print 'mparent:', mparent + if tag: + print 'tag:', tag + print '-----------------------------------------' + + # checkout the parent if necessary + if cset != 0: + if hgbranch[str(cset)] == "branch-" + str(cset): + print 'creating new branch', hgbranch[str(cset)] + os.system('git-checkout -b %s %s' % (hgbranch[str(cset)], hgvers[parent])) + else: + print 'checking out branch', hgbranch[str(cset)] + os.system('git-checkout %s' % hgbranch[str(cset)]) + + # merge + if mparent: + if hgbranch[parent] == hgbranch[str(cset)]: + otherbranch = hgbranch[mparent] + else: + otherbranch = hgbranch[parent] + print 'merging', otherbranch, 'into', hgbranch[str(cset)] + os.system(getgitenv(user, date) + 'git-merge --no-commit -s ours "" %s %s' % (hgbranch[str(cset)], otherbranch)) + + # remove everything except .git and .hg directories + os.system('find . \( -path "./.hg" -o -path "./.git" \) -prune -o ! -name "." -print | xargs rm -rf') + + # repopulate with checkouted files + os.system('hg update -C %d' % cset) + + # add new files + os.system('git-ls-files -x .hg --others | git-update-index --add --stdin') + # delete removed files + os.system('git-ls-files -x .hg --deleted | git-update-index --remove --stdin') + + # commit + os.system(getgitenv(user, date) + 'git-commit -a -F %s' % filecomment) + os.unlink(filecomment) + + # tag + if tag and tag != 'tip': + os.system(getgitenv(user, date) + 'git-tag %s' % tag) + + # delete branch if not used anymore... + if mparent and len(hgchildren[str(cset)]): + print "Deleting unused branch:", otherbranch + os.system('git-branch -d %s' % otherbranch) + + # retrieve and record the version + vvv = os.popen('git-show | head -1').read() + vvv = vvv[vvv.index(' ') + 1 : ].strip() + print 'record', cset, '->', vvv + hgvers[str(cset)] = vvv + +os.system('git-repack -a -d') + +# write the state for incrementals +if state: + print 'Writing state' + f = open(state, 'w') + pickle.dump(hgvers, f) + +# vim: et ts=8 sw=4 sts=4 diff --git a/contrib/hg-to-git/hg-to-git.txt b/contrib/hg-to-git/hg-to-git.txt new file mode 100644 index 0000000..cf1c735 --- /dev/null +++ b/contrib/hg-to-git/hg-to-git.txt @@ -0,0 +1,22 @@ +hg-to-git.py is able to convert a Mercurial repository into a git one, +and preserves the branches in the process (unlike tailor) + +hg-to-git.py can probably be greatly improved (it's a rather crude +combination of shell and python) but it does already work quite well for +me. Features: + - supports incremental conversion + (for keeping a git repo in sync with a hg one) + - supports hg branches + - converts hg tags + +Note that the git repository will be created 'in place' (at the same +location as the source hg repo). You will have to manually remove the +'.hg' directory after the conversion. + +Also note that the incremental conversion uses 'simple' hg changesets +identifiers (ordinals, as opposed to SHA-1 ids), and since these ids +are not stable across different repositories the hg-to-git.py state file +is forever tied to one hg repository. + +-- +Stelian Pop <stelian@popies.net>
-- 1.4.4.4