contrib/hgit

Fix 3-way-merge of original parent, workdir and new parent.

The dirstate has to match what is in the repository (what would be
checked out with 'hg update -C'), because the resulting file may be
identical to the new parent, or it may be completely different.
Previously the dirstate wasn't updated, so if you changed the file to
look like the original parent, it might be considered unmodified
relative to the new parent.

#!/usr/bin/env python
#
# Minimal support for git commands on an hg repository
#
# Copyright 2005 Chris Mason <[e-mail]>
#
# This software may be used and distributed according to the terms
# of the GNU General Public License, incorporated herein by reference.

import time, sys, signal
from mercurial import hg, mdiff, fancyopts, commands, ui
    
def difftree(args, ui, repo):
    def __difftree(repo, files = None, node1 = None, node2 = None):
        def date(c):
            return time.asctime(time.gmtime(float(c[2].split(' ')[0])))

        if node2:
            change = repo.changelog.read(node2)
            mmap2 = repo.manifest.read(change[0])
            (c, a, d, u) = repo.changes(node1, node2)
            def read(f): return repo.file(f).read(mmap2[f])
            date2 = date(change)
        else:
            date2 = time.asctime()
            (c, a, d, u) = repo.diffdir(repo.root, node1)
            if not node1:
                node1 = repo.dirstate.parents()[0]
            def read(f): return file(os.path.join(repo.root, f)).read()

        change = repo.changelog.read(node1)
        mmap = repo.manifest.read(change[0])
        date1 = date(change)
        empty = "0" * 40;

        if files:
            c, a, d = map(lambda x: filterfiles(files, x), (c, a, d))

        for f in c:
            # TODO get file permissions
            print ":100664 100664 %s %s M\t%s\t%s" % (hg.hex(mmap[f]), 
                                                      hg.hex(mmap2[f]), f, f)
        for f in a:
            print ":000000 100664 %s %s N\t%s\t%s" % (empty, hg.hex(mmap2[f]), f, f)
        for f in d:
            print ":100664 000000 %s %s D\t%s\t%s" % (hg.hex(mmap[f]), empty, f, f)
    ##

    revs = []
    if args:
        doptions = {}
        opts = [('p', 'patch', None, 'patch'),
                ('r', 'recursive', None, 'recursive')]
        args = fancyopts.fancyopts(args, opts, doptions)

    if len(args) < 2:
        help()
        sys.exit(1)
    revs.append(repo.lookup(args[0]))
    revs.append(repo.lookup(args[1]))
    args = args[2:]
    if doptions['patch']:
        commands.dodiff(sys.stdout, ui, repo, args, *revs)
    else:
        __difftree(repo, args, *revs)

def catcommit(repo, n, prefix):
    nlprefix = '\n' + prefix;
    changes = repo.changelog.read(n)
    (p1, p2) = repo.changelog.parents(n)
    (h, h1, h2) = map(hg.hex, (n, p1, p2))
    (i1, i2) = map(repo.changelog.rev, (p1, p2))
    print "tree %s" % (h)
    if i1 != -1: print "%sparent %s" % (prefix, h1)
    if i2 != -1: print "%sparent %s" % (prefix, h2)
    date_ar = changes[2].split(' ')
    date = int(float(date_ar[0]))
    print "%sauthor <%s> %s %s" % (prefix, changes[1], date, date_ar[1])
    print "%scommitter <%s> %s %s" % (prefix, changes[1], date, date_ar[1])
    print prefix
    if prefix != "":
        print "%s%s" % (prefix, changes[4].replace('\n', nlprefix).strip())
    else:
        print changes[4]

def catfile(args, ui, repo):
    doptions = {}
    opts = [('s', 'stdin', None, 'stdin')]
    args = fancyopts.fancyopts(args, opts, doptions)

    # in stdin mode, every line except the commit is prefixed with two
    # spaces.  This way the our caller can find the commit without magic
    # strings
    #
    prefix = ""
    if doptions['stdin']:
        try:
            (type, r) = raw_input().split(' ');
            prefix = "  "
        except EOFError:
            return

    else:
        if len(args) < 2:
            help()
            sys.exit(1)
        type = args[0]
        r = args[1]

    while r:
        if type != "commit":
            sys.stderr.write("aborting hg cat-file only understands commits\n")
            sys.exit(1);
        n = repo.lookup(r)
        catcommit(repo, n, prefix)
        if doptions['stdin']:
            try:
                (type, r) = raw_input().split(' ');
            except EOFError:
                break
        else:
            break

# git rev-tree is a confusing thing.  You can supply a number of
# commit sha1s on the command line, and it walks the commit history
# telling you which commits are reachable from the supplied ones via
# a bitmask based on arg position.
# you can specify a commit to stop at by starting the sha1 with ^
def revtree(args, repo, full="tree", maxnr=0):
    # calculate and return the reachability bitmask for sha
    def is_reachable(ar, reachable, sha):
        if len(ar) == 0:
            return 1
        mask = 0
        for i in range(len(ar)):
            if sha in reachable[i]:
                mask |= 1 << i

        return mask

    reachable = []
    stop_sha1 = []
    want_sha1 = []
    count = 0

    # figure out which commits they are asking for and which ones they
    # want us to stop on
    for i in range(len(args)):
        if args[i].startswith('^'):
            s = repo.lookup(args[i][1:])
            stop_sha1.append(s)
            want_sha1.append(s)
        elif args[i] != 'HEAD':
            want_sha1.append(repo.lookup(args[i]))

    # calculate the graph for the supplied commits
    for i in range(len(want_sha1)):
        reachable.append({});
        n = want_sha1[i];
        visit = [n];
        reachable[i][n] = 1
        while visit:
            n = visit.pop(0)
            if n in stop_sha1:
                break
            for p in repo.changelog.parents(n):
                if p not in reachable[i]:
                    reachable[i][p] = 1
                    visit.append(p)
                if p in stop_sha1:
                    break

    # walk the repository looking for commits that are in our
    # reachability graph
    for i in range(repo.changelog.count()-1, -1, -1):
        n = repo.changelog.node(i)
        mask = is_reachable(want_sha1, reachable, n)
        if mask:
            if not full:
                print hg.hex(n)
            elif full is "commit":
                print hg.hex(n)
                catcommit(repo, n, '  ')
            else:
                changes = repo.changelog.read(n)
                (p1, p2) = repo.changelog.parents(n)
                (h, h1, h2) = map(hg.hex, (n, p1, p2))
                (i1, i2) = map(repo.changelog.rev, (p1, p2))

                date = changes[2].split(' ')[0]
                print "%s %s:%s" % (date, h, mask),
                mask = is_reachable(want_sha1, reachable, p1)
                if i1 != -1 and mask > 0:
                    print "%s:%s " % (h1, mask),
                mask = is_reachable(want_sha1, reachable, p2)
                if i2 != -1 and mask > 0:
                    print "%s:%s " % (h2, mask),
                print ""
            if maxnr and count >= maxnr:
                break
            count += 1

# git rev-list tries to order things by date, and has the ability to stop
# at a given commit without walking the whole repo.  TODO add the stop
# parameter
def revlist(args, repo):
    doptions = {}
    opts = [('c', 'commit', None, 'commit'),
            ('n', 'max-nr', 0, 'max-nr')]
    args = fancyopts.fancyopts(args, opts, doptions)
    if doptions['commit']:
        full = "commit"
    else:
        full = None
    for i in range(1, len(args)):
        args[i] = '^' + args[i]
    revtree(args, repo, full, doptions['max-nr'])

def catchterm(*args):
    raise SignalInterrupt

def help():
    sys.stderr.write("commands:\n")
    sys.stderr.write("  hgit cat-file [type] sha1\n")
    sys.stderr.write("  hgit diff-tree [-p] [-r] sha1 sha1\n")
    sys.stderr.write("  hgit rev-tree [sha1 ... [^stop sha1]]\n")
    sys.stderr.write("  hgit rev-list [-c] [sha1 [stop sha1]\n")

cmd = sys.argv[1]
args = sys.argv[2:]
u = ui.ui()
signal.signal(signal.SIGTERM, catchterm)
repo = hg.repository(ui = u)

if cmd == "diff-tree":
    difftree(args, u, repo)

elif cmd == "cat-file":
    catfile(args, u, repo)

elif cmd == "rev-tree":
    revtree(args, repo)

elif cmd == "rev-list":
    revlist(args, repo)

elif cmd == "help":
    help()

else:
    if cmd: sys.stderr.write("unknown command\n\n")
    help()
    sys.exit(1)

sys.exit(0)