new file mode 100644
--- /dev/null
+++ b/hgext/record.py
@@ -0,0 +1,381 @@
+# record.py
+#
+# Copyright 2007 Bryan O'Sullivan <bos@serpentine.com>
+#
+# This software may be used and distributed according to the terms of
+# the GNU General Public License, incorporated herein by reference.
+
+'''interactive change selection during commit'''
+
+from mercurial.i18n import _
+from mercurial import cmdutil, commands, cmdutil, hg, mdiff, patch, revlog
+from mercurial import util
+import copy, cStringIO, errno, operator, os, re, shutil, tempfile
+
+lines_re = re.compile(r'@@ -(\d+),(\d+) \+(\d+),(\d+) @@\s*(.*)')
+
+def scanpatch(fp):
+    lr = patch.linereader(fp)
+
+    def scanwhile(first, p):
+        lines = [first]
+        while True:
+            line = lr.readline()
+            if not line:
+                break
+            if p(line):
+                lines.append(line)
+            else:
+                lr.push(line)
+                break
+        return lines
+
+    while True:
+        line = lr.readline()
+        if not line:
+            break
+        if line.startswith('diff --git a/'):
+            def notheader(line):
+                s = line.split(None, 1)
+                return not s or s[0] not in ('---', 'diff')
+            header = scanwhile(line, notheader)
+            fromfile = lr.readline()
+            if fromfile.startswith('---'):
+                tofile = lr.readline()
+                header += [fromfile, tofile]
+            else:
+                lr.push(fromfile)
+            yield 'file', header
+        elif line[0] == ' ':
+            yield 'context', scanwhile(line, lambda l: l[0] in ' \\')
+        elif line[0] in '-+':
+            yield 'hunk', scanwhile(line, lambda l: l[0] in '-+\\')
+        else:
+            m = lines_re.match(line)
+            if m:
+                yield 'range', m.groups()
+            else:
+                raise patch.PatchError('unknown patch content: %r' % line)
+
+class header(object):
+    diff_re = re.compile('diff --git a/(.*) b/(.*)$')
+    allhunks_re = re.compile('(?:index|new file|deleted file) ')
+    pretty_re = re.compile('(?:new file|deleted file) ')
+    special_re = re.compile('(?:index|new|deleted|copy|rename) ')
+
+    def __init__(self, header):
+        self.header = header
+        self.hunks = []
+
+    def binary(self):
+        for h in self.header:
+            if h.startswith('index '):
+                return True
+        
+    def pretty(self, fp):
+        for h in self.header:
+            if h.startswith('index '):
+                fp.write(_('this modifies a binary file (all or nothing)\n'))
+                break
+            if self.pretty_re.match(h):
+                fp.write(h)
+                if self.binary():
+                    fp.write(_('this is a binary file\n'))
+                break
+            if h.startswith('---'):
+                fp.write(_('%d hunks, %d lines changed\n') %
+                         (len(self.hunks),
+                          sum([h.added + h.removed for h in self.hunks])))
+                break
+            fp.write(h)
+
+    def write(self, fp):
+        fp.write(''.join(self.header))
+
+    def allhunks(self):
+        for h in self.header:
+            if self.allhunks_re.match(h):
+                return True
+
+    def files(self):
+        fromfile, tofile = self.diff_re.match(self.header[0]).groups()
+        if fromfile == tofile:
+            return [fromfile]
+        return [fromfile, tofile]
+
+    def filename(self):
+        return self.files()[-1]
+
+    def __repr__(self):
+        return '<header %s>' % (' '.join(map(repr, self.files())))
+
+    def special(self):
+        for h in self.header:
+            if self.special_re.match(h):
+                return True
+
+def countchanges(hunk):
+    add = len([h for h in hunk if h[0] == '+'])
+    rem = len([h for h in hunk if h[0] == '-'])
+    return add, rem
+
+class hunk(object):
+    maxcontext = 3
+
+    def __init__(self, header, fromline, toline, proc, before, hunk, after):
+        def trimcontext(number, lines):
+            delta = len(lines) - self.maxcontext
+            if False and delta > 0:
+                return number + delta, lines[:self.maxcontext]
+            return number, lines
+
+        self.header = header
+        self.fromline, self.before = trimcontext(fromline, before)
+        self.toline, self.after = trimcontext(toline, after)
+        self.proc = proc
+        self.hunk = hunk
+        self.added, self.removed = countchanges(self.hunk)
+
+    def write(self, fp):
+        delta = len(self.before) + len(self.after)
+        fromlen = delta + self.removed
+        tolen = delta + self.added
+        fp.write('@@ -%d,%d +%d,%d @@%s\n' %
+                 (self.fromline, fromlen, self.toline, tolen,
+                  self.proc and (' ' + self.proc)))
+        fp.write(''.join(self.before + self.hunk + self.after))
+
+    pretty = write
+
+    def filename(self):
+        return self.header.filename()
+
+    def __repr__(self):
+        return '<hunk %r@%d>' % (self.filename(), self.fromline)
+
+def parsepatch(fp):
+    class parser(object):
+        def __init__(self):
+            self.fromline = 0
+            self.toline = 0
+            self.proc = ''
+            self.header = None
+            self.context = []
+            self.before = []
+            self.hunk = []
+            self.stream = []
+
+        def addrange(self, (fromstart, fromend, tostart, toend, proc)):
+            self.fromline = int(fromstart)
+            self.toline = int(tostart)
+            self.proc = proc
+
+        def addcontext(self, context):
+            if self.hunk:
+                h = hunk(self.header, self.fromline, self.toline, self.proc,
+                         self.before, self.hunk, context)
+                self.header.hunks.append(h)
+                self.stream.append(h)
+                self.fromline += len(self.before) + h.removed
+                self.toline += len(self.before) + h.added
+                self.before = []
+                self.hunk = []
+                self.proc = ''
+            self.context = context
+
+        def addhunk(self, hunk):
+            if self.context:
+                self.before = self.context
+                self.context = []
+            self.hunk = data
+
+        def newfile(self, hdr):
+            self.addcontext([])
+            h = header(hdr)
+            self.stream.append(h)
+            self.header = h
+
+        def finished(self):
+            self.addcontext([])
+            return self.stream
+
+        transitions = {
+            'file': {'context': addcontext,
+                     'file': newfile,
+                     'hunk': addhunk,
+                     'range': addrange},
+            'context': {'file': newfile,
+                        'hunk': addhunk,
+                        'range': addrange},
+            'hunk': {'context': addcontext,
+                     'file': newfile,
+                     'range': addrange},
+            'range': {'context': addcontext,
+                      'hunk': addhunk},
+            }
+             
+    p = parser()
+
+    state = 'context'
+    for newstate, data in scanpatch(fp):
+        try:
+            p.transitions[state][newstate](p, data)
+        except KeyError:
+            raise patch.PatchError('unhandled transition: %s -> %s' %
+                                   (state, newstate))
+        state = newstate
+    return p.finished()
+
+def filterpatch(ui, chunks):
+    chunks = list(chunks)
+    chunks.reverse()
+    seen = {}
+    def consumefile():
+        consumed = []
+        while chunks:
+            if isinstance(chunks[-1], header):
+                break
+            else:
+                consumed.append(chunks.pop())
+        return consumed
+    resp = None
+    applied = {}
+    while chunks:
+        chunk = chunks.pop()
+        if isinstance(chunk, header):
+            fixoffset = 0
+            hdr = ''.join(chunk.header)
+            if hdr in seen:
+                consumefile()
+                continue
+            seen[hdr] = True
+            if not resp:
+                chunk.pretty(ui)
+            r = resp or ui.prompt(_('record changes to %s? [y]es [n]o') %
+                                  _(' and ').join(map(repr, chunk.files())),
+                                  '(?:|[yYnNqQaA])$') or 'y'
+            if r in 'aA':
+                r = 'y'
+                resp = 'y'
+            if r in 'qQ':
+                raise util.Abort(_('user quit'))
+            if r in 'yY':
+                applied[chunk.filename()] = [chunk]
+                if chunk.allhunks():
+                    applied[chunk.filename()] += consumefile()
+            else:
+                consumefile()
+        else:
+            if not resp:
+                chunk.pretty(ui)
+            r = resp or ui.prompt(_('record this change to %r? [y]es [n]o') %
+                                  chunk.filename(), '(?:|[yYnNqQaA])$') or 'y'
+            if r in 'aA':
+                r = 'y'
+                resp = 'y'
+            if r in 'qQ':
+                raise util.Abort(_('user quit'))
+            if r in 'yY':
+                if fixoffset:
+                    chunk = copy.copy(chunk)
+                    chunk.toline += fixoffset
+                applied[chunk.filename()].append(chunk)
+            else:
+                fixoffset += chunk.removed - chunk.added
+    return reduce(operator.add, [h for h in applied.itervalues()
+                                 if h[0].special() or len(h) > 1], [])
+
+def record(ui, repo, *pats, **opts):
+    '''interactively select changes to commit'''
+
+    if not ui.interactive:
+        raise util.Abort(_('running non-interactively, use commit instead'))
+
+    def recordfunc(ui, repo, files, message, match, opts):
+        if files:
+            changes = None
+        else:
+            changes = repo.status(files=files, match=match)[:5]
+            modified, added, removed = changes[:3]
+            files = modified + added + removed
+        diffopts = mdiff.diffopts(git=True, nodates=True)
+        fp = cStringIO.StringIO()
+        patch.diff(repo, repo.dirstate.parents()[0], files=files,
+                   match=match, changes=changes, opts=diffopts, fp=fp)
+        fp.seek(0)
+
+        chunks = filterpatch(ui, parsepatch(fp))
+        del fp
+
+        contenders = {}
+        for h in chunks:
+            try: contenders.update(dict.fromkeys(h.files()))
+            except AttributeError: pass
+            
+        newfiles = [f for f in files if f in contenders]
+
+        if not newfiles:
+            ui.status(_('no changes to record\n'))
+            return 0
+
+        if changes is None:
+            changes = repo.status(files=newfiles, match=match)[:5]
+        modified = dict.fromkeys(changes[0])
+
+        backups = {}
+        backupdir = repo.join('record-backups')
+        try:
+            os.mkdir(backupdir)
+        except OSError, err:
+            if err.errno == errno.EEXIST:
+                pass
+        try:
+            for f in newfiles:
+                if f not in modified:
+                    continue
+                fd, tmpname = tempfile.mkstemp(prefix=f.replace('/', '_')+'.',
+                                               dir=backupdir)
+                os.close(fd)
+                ui.debug('backup %r as %r\n' % (f, tmpname))
+                util.copyfile(repo.wjoin(f), tmpname)
+                backups[f] = tmpname
+
+            fp = cStringIO.StringIO()
+            for c in chunks:
+                if c.filename() in backups:
+                    c.write(fp)
+            dopatch = fp.tell()
+            fp.seek(0)
+
+            if backups:
+                hg.revert(repo, repo.dirstate.parents()[0], backups.has_key)
+
+            if dopatch:
+                ui.debug('applying patch\n')
+                ui.debug(fp.getvalue())
+                patch.internalpatch(fp, ui, 1, repo.root)
+            del fp
+
+            repo.commit(newfiles, message, opts['user'], opts['date'], match,
+                        force_editor=opts.get('force_editor'))
+            return 0
+        finally:
+            try:
+                for realname, tmpname in backups.iteritems():
+                    ui.debug('restoring %r to %r\n' % (tmpname, realname))
+                    util.copyfile(tmpname, realname)
+                    os.unlink(tmpname)
+                os.rmdir(backupdir)
+            except OSError:
+                pass
+    return cmdutil.commit(ui, repo, recordfunc, pats, opts)
+
+cmdtable = {
+    'record':
+    (record, [('A', 'addremove', None,
+               _('mark new/missing files as added/removed before committing')),
+              ('d', 'date', '', _('record datecode as commit date')),
+              ('u', 'user', '', _('record user as commiter')),
+              ] + commands.walkopts + commands.commitopts,
+     _('hg record [FILE]...')),
+    }