Patchwork [4,of,4] shelve: add a shelve extension to save/restore working changes

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Submitter Bryan O'Sullivan
Date May 28, 2013, 11:28 p.m.
Message ID <a87ee920b333192898e8.1369783737@australite.thefacebook.com>
Download mbox | patch
Permalink /patch/1672/
State Superseded, archived
Commit 49d4919d21c2fe79957d160d64acd048bf6a2e7b
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Bryan O'Sullivan - May 28, 2013, 11:28 p.m.
# HG changeset patch
# User Bryan O'Sullivan <bryano@fb.com>
# Date 1369783721 25200
#      Tue May 28 16:28:41 2013 -0700
# Node ID a87ee920b333192898e8ff84e30ddb1ebac515b6
# Parent  11fce4dc68f060e96cc06cc88da72e2c9da1022b
shelve: add a shelve extension to save/restore working changes

This extension saves shelved changes using a temporary draft commit,
and bundles all draft ancestors of the temporary commit. This
strategy makes it possible to use Mercurial's merge machinery to
resolve conflicts if necessary when unshelving, even when the
destination commit or its ancestors have been amended, squashed,
or evolved.

Although this extension shares its name and some functionality with
the third party hgshelve extension, it has little else in common.
Notably, the hgshelve extension shelves changes as unified diffs,
which makes conflict resolution a matter of finding .rej files and
cleaning up the mess by hand.

We do not yet allow hunk-level choosing of changes to record.
Compared to the hgshelve extension, this is a small regression in
usability, but we hope to integrate that at a later point, once the
record machinery becomes more reusable and robust.
Augie Fackler - May 29, 2013, 12:20 a.m.
On May 28, 2013, at 7:28 PM, Bryan O'Sullivan <bos@serpentine.com> wrote:

> # HG changeset patch
> # User Bryan O'Sullivan <bryano@fb.com>
> # Date 1369783721 25200
> #      Tue May 28 16:28:41 2013 -0700
> # Node ID a87ee920b333192898e8ff84e30ddb1ebac515b6
> # Parent  11fce4dc68f060e96cc06cc88da72e2c9da1022b
> shelve: add a shelve extension to save/restore working changes

One code style question.

I wonder if we shouldn't take a step back and have some central registry of things that could be in-progress, since an in-progress histedit, merge, rebase, or graft should abort this, and not all of those will necessarily look like a merge (and the abort message could be confusing).

> 
> This extension saves shelved changes using a temporary draft commit,
> and bundles all draft ancestors of the temporary commit. This
> strategy makes it possible to use Mercurial's merge machinery to
> resolve conflicts if necessary when unshelving, even when the
> destination commit or its ancestors have been amended, squashed,
> or evolved.
> 
> Although this extension shares its name and some functionality with
> the third party hgshelve extension, it has little else in common.
> Notably, the hgshelve extension shelves changes as unified diffs,
> which makes conflict resolution a matter of finding .rej files and
> cleaning up the mess by hand.
> 
> We do not yet allow hunk-level choosing of changes to record.
> Compared to the hgshelve extension, this is a small regression in
> usability, but we hope to integrate that at a later point, once the
> record machinery becomes more reusable and robust.
> 
> diff --git a/hgext/color.py b/hgext/color.py
> --- a/hgext/color.py
> +++ b/hgext/color.py
> @@ -63,6 +63,10 @@ Default effects may be overridden from y
>   rebase.rebased = blue
>   rebase.remaining = red bold
> 
> +  shelve.age = cyan
> +  shelve.newest = green bold
> +  shelve.name = blue bold
> +
>   histedit.remaining = red bold
> 
> The available effects in terminfo mode are 'blink', 'bold', 'dim',
> @@ -260,6 +264,9 @@ except ImportError:
>            'rebase.remaining': 'red bold',
>            'resolve.resolved': 'green bold',
>            'resolve.unresolved': 'red bold',
> +           'shelve.age': 'cyan',
> +           'shelve.newest': 'green bold',
> +           'shelve.name': 'blue bold',
>            'status.added': 'green bold',
>            'status.clean': 'none',
>            'status.copied': 'none',
> diff --git a/hgext/shelve.py b/hgext/shelve.py
> new file mode 100644
> --- /dev/null
> +++ b/hgext/shelve.py
> @@ -0,0 +1,552 @@
> +# shelve.py - save/restore working directory state
> +#
> +# Copyright 2013 Facebook, Inc.
> +#
> +# This software may be used and distributed according to the terms of the
> +# GNU General Public License version 2 or any later version.
> +
> +'''save and restore changes to the working directory
> +
> +The "hg shelve" command saves changes made to the working directory
> +and reverts those changes, resetting the working directory to a clean
> +state.
> +
> +Later on, the "hg unshelve" command restores the changes saved by "hg
> +shelve". Changes can be restored even after updating to a different
> +parent, in which case Mercurial's merge machinery will resolve any
> +conflicts if necessary.
> +
> +You can have more than one shelved change outstanding at a time; each
> +shelved change has a distinct name. For details, see the help for "hg
> +shelve".
> +'''
> +
> +from mercurial.i18n import _
> +from mercurial.node import nullid
> +from mercurial import changegroup, cmdutil, commands, extensions, pvec, scmutil
> +from mercurial import error, hg, mdiff, merge, node, patch, repair, util
> +from mercurial import templatefilters
> +from mercurial import lock as lockmod
> +import errno, os, time
> +
> +cmdtable = {}
> +command = cmdutil.command(cmdtable)
> +testedwith = 'internal'
> +
> +def shelvedfilename(repo, name, filetype):
> +    return os.path.join(repo.join('shelved'), name + '.' + filetype)
> +
> +def shelvedfile(repo, name, filetype, mode='rb'):
> +    '''Open a file used for storing data associated with a shelved change.'''
> +    try:
> +        return open(shelvedfilename(repo, name, filetype), mode)
> +    except IOError, err:
> +        if err.errno == errno.ENOENT:
> +            if mode[0] in 'wa':
> +                try:
> +                    repo.vfs.mkdir(repo.join('shelved'))
> +                    return open(shelvedfilename(repo, name, filetype), mode)
> +                except IOError, err:
> +                    if err.errno != errno.EEXIST:
> +                        raise
> +            elif mode[0] =='r':
> +                raise util.Abort(_("shelved change '%s' not found") % name)
> +        raise
> +
> +class shelvedstate(object):
> +    @classmethod
> +    def load(cls, repo):
> +        fp = repo.opener('shelvedstate')
> +        try:
> +            lines = fp.read().splitlines()
> +        finally:
> +            fp.close()
> +        lines.reverse()
> +
> +        version = lines.pop()
> +        obj = cls()
> +        obj.name = lines.pop()
> +        obj.parents = [node.bin(n) for n in lines.pop().split()]
> +        obj.stripnodes = [node.bin(n) for n in lines]
> +        return obj
> +
> +    @staticmethod
> +    def save(repo, name, oldtiprev):
> +        fp = repo.opener('shelvedstate', 'wb')
> +        fp.write('1\n')
> +        fp.write(name + '\n')
> +        fp.write(' '.join(node.hex(n) for n in repo.dirstate.parents()) + '\n')
> +        # save revs that need to be stripped when we are done
> +        for rev in xrange(oldtiprev, len(repo)):
> +            fp.write(node.hex(repo.changelog.node(rev)) + '\n')
> +        fp.close()
> +
> +    @staticmethod
> +    def clear(repo):
> +        util.unlinkpath(repo.join('shelvedstate'), ignoremissing=True)
> +
> +def createcmd(ui, repo, pats, opts):
> +    def publicancestors(ctx):

why is this function nested?

> +        '''Compute the heads of the public ancestors of a commit.
> +
> +        Much faster than the revset heads(ancestors(ctx) - draft())'''
> +        seen = set()
> +        visit = util.deque()
> +        visit.append(ctx)
> +        while visit:
> +            ctx = visit.popleft()
> +            for parent in ctx.parents():
> +                rev = parent.rev()
> +                if rev not in seen:
> +                    seen.add(rev)
> +                    if parent.mutable():
> +                        visit.append(parent)
> +                    else:
> +                        yield parent.node()
> +
> +    try:
> +        shelvedstate.load(repo)
> +        raise util.Abort(_('unshelve already in progress'))
> +    except IOError, err:
> +        if err.errno != errno.ENOENT:
> +            raise
> +
> +    wctx = repo[None]
> +    parents = wctx.parents()
> +    if len(parents) > 1:
> +        raise util.Abort(_('cannot shelve while merging'))
> +    parent = parents[0]
> +    if parent.node() == nullid:
> +        raise util.Abort(_('cannot shelve - repo has no history'))
> +
> +    try:
> +        user = repo.ui.username()
> +    except util.Abort:
> +        user = 'shelve@localhost'
> +
> +    label = repo._bookmarkcurrent or parent.branch()
> +
> +    def gennames():
> +        yield label
> +        for i in xrange(1, 100):
> +            yield '%s-%02d' % (label, i)
> +
> +    shelvedfiles = []
> +
> +    def commitfunc(ui, repo, message, match, opts):
> +        for flist in repo.status(match=match)[:4]:
> +            shelvedfiles.extend(flist)
> +        return repo.commit(message, user, opts.get('date'), match)
> +
> +    desc = parent.description().split('\n', 1)[0]
> +    desc = _('shelved from %s (%s): %s') % (label, str(parent)[:8], desc)
> +
> +    if not opts['message']:
> +        opts['message'] = desc
> +
> +    name = opts['name']
> +    if '/' in name or '\\' in name:
> +        raise util.Abort(_('shelved change names may not contain slashes'))
> +    if name.startswith('.'):
> +        raise util.Abort(_("shelved change names may not start with '.'"))
> +    if name:
> +        if os.path.exists(shelvedfilename(repo, name, 'hg')):
> +            raise util.Abort(_("a shelved change named '%s' already exists")
> +                             % name)
> +
> +    wlock = lock = None
> +    try:
> +        wlock = repo.wlock()
> +        lock = repo.lock()
> +
> +        if not name:
> +            for name in gennames():
> +                if not os.path.exists(shelvedfilename(repo, name, 'hg')):
> +                    break
> +            else:
> +                raise util.Abort(_("too many shelved changes named '%s'") %
> +                                 label)
> +
> +        node = cmdutil.commit(ui, repo, commitfunc, pats, opts)
> +
> +        if not node:
> +            stat = repo.status(match=scmutil.match(repo[None], pats, opts))
> +            if stat[3]:
> +                ui.status(_("nothing changed (%d missing files, see "
> +                            "'hg status')\n") % len(stat[3]))
> +            else:
> +                ui.status(_("nothing changed\n"))
> +            return 1
> +
> +        shelvedfile(repo, name, 'files', 'wb').write('\0'.join(shelvedfiles))
> +
> +        bases = list(publicancestors(repo[node]))
> +        cg = repo.changegroupsubset(bases, [node], 'shelve')
> +        changegroup.writebundle(cg, shelvedfilename(repo, name, 'hg'),
> +                                'HG10UN')
> +        cmdutil.export(repo, [node],
> +                       fp=shelvedfile(repo, name, 'patch', 'wb'),
> +                       opts=mdiff.diffopts(git=True))
> +
> +        if ui.formatted():
> +            desc = util.ellipsis(desc, ui.termwidth())
> +        ui.status(desc + '\n')
> +        ui.status(_('shelved as %s\n') % name)
> +        hg.update(repo, parent.node())
> +        repair.strip(ui, repo, [node], backup='none', topic='shelve')
> +    finally:
> +        lockmod.release(lock, wlock)
> +
> +def cleanupcmd(ui, repo):
> +    path = repo.join('shelved')
> +    wlock = None
> +    try:
> +        wlock = repo.wlock()
> +        for name in os.listdir(path):
> +            suffix = name.rsplit('.', 1)[-1]
> +            if suffix in ('hg', 'files', 'patch'):
> +                os.unlink(os.path.join(path, name))
> +    finally:
> +        lockmod.release(wlock)
> +
> +def deletecmd(ui, repo, pats):
> +    if not pats:
> +        raise util.Abort(_('no shelved changes specified!'))
> +    wlock = None
> +    try:
> +        wlock = repo.wlock()
> +        try:
> +            for name in pats:
> +                for suffix in 'hg files patch'.split():
> +                    os.unlink(shelvedfilename(repo, name, suffix))
> +        except OSError, err:
> +            if err.errno != errno.ENOENT:
> +                raise
> +            raise util.Abort(_("shelved change '%s' not found") % name)
> +    finally:
> +        lockmod.release(wlock)
> +
> +def listshelves(repo):
> +    path = repo.join('shelved')
> +    try:
> +        names = os.listdir(path)
> +    except OSError, err:
> +        if err.errno != errno.ENOENT:
> +            raise
> +        return []
> +    info = []
> +    for name in names:
> +        pfx, sfx = name.rsplit('.', 1)
> +        if not pfx or sfx != 'patch':
> +            continue
> +        st = os.lstat(os.path.join(path, name))
> +        info.append((st.st_mtime, os.path.join(path, pfx)))
> +    return sorted(info, reverse=True)
> +
> +def listcmd(ui, repo, pats, opts):
> +    pats = set(pats)
> +    width = 80
> +    if not ui.plain():
> +        width = ui.termwidth()
> +    namelabel = 'shelve.newest'
> +    for mtime, name in listshelves(repo):
> +        sname = os.path.basename(name)
> +        if pats and sname not in pats:
> +            continue
> +        ui.write(sname, label=namelabel)
> +        namelabel = 'shelve.name'
> +        if ui.quiet:
> +            ui.write('\n')
> +            continue
> +        ui.write(' ' * (16 - len(sname)))
> +        used = 16
> +        age = '[%s]' % templatefilters.age(util.makedate(mtime))
> +        ui.write(age, label='shelve.age')
> +        ui.write(' ' * (18 - len(age)))
> +        used += 18
> +        fp = open(name + '.patch', 'rb')
> +        try:
> +            while True:
> +                line = fp.readline()
> +                if not line:
> +                    break
> +                if not line.startswith('#'):
> +                    desc = line.rstrip()
> +                    if ui.formatted():
> +                        desc = util.ellipsis(desc, width - used)
> +                    ui.write(desc)
> +                    break
> +            ui.write('\n')
> +            if not (opts['patch'] or opts['stat']):
> +                continue
> +            difflines = fp.readlines()
> +            if opts['patch']:
> +                for chunk, label in patch.difflabel(iter, difflines):
> +                    ui.write(chunk, label=label)
> +            if opts['stat']:
> +                for chunk, label in patch.diffstatui(difflines, width=width,
> +                                                     git=True):
> +                    ui.write(chunk, label=label)
> +        finally:
> +            fp.close()
> +
> +def readshelvedfiles(repo, basename):
> +    return shelvedfile(repo, basename, 'files').read().split('\0')
> +
> +def checkparents(repo, state):
> +    if state.parents != repo.dirstate.parents():
> +        raise util.Abort(_('working directory parents do not match unshelve '
> +                           'state'))
> +
> +def unshelveabort(ui, repo, state, opts):
> +    wlock = repo.wlock()
> +    lock = None
> +    try:
> +        checkparents(repo, state)
> +        lock = repo.lock()
> +        merge.mergestate(repo).reset()
> +        if opts['keep']:
> +            repo.setparents(repo.dirstate.parents()[0])
> +        else:
> +            revertfiles = readshelvedfiles(repo, state.name)
> +            wctx = repo.parents()[0]
> +            cmdutil.revert(ui, repo, wctx, [wctx.node(), nullid],
> +                           *revertfiles, no_backup=True)
> +            # fix up the weird dirstate states the merge left behind
> +            mf = wctx.manifest()
> +            dirstate = repo.dirstate
> +            for f in revertfiles:
> +                if f in mf:
> +                    dirstate.normallookup(f)
> +                else:
> +                    dirstate.drop(f)
> +            dirstate._pl = (wctx.node(), nullid)
> +            dirstate._dirty = True
> +        repair.strip(ui, repo, state.stripnodes, backup='none', topic='shelve')
> +        shelvedstate.clear(repo)
> +        ui.warn(_("unshelve of '%s' aborted\n" % state.name))
> +    finally:
> +        lockmod.release(lock, wlock)
> +
> +def unshelvecleanup(ui, repo, name, opts):
> +    if not opts['keep']:
> +        for filetype in 'hg files patch'.split():
> +            os.unlink(shelvedfilename(repo, name, filetype))
> +
> +def unshelvecontinue(ui, repo, state, opts):
> +    # We're finishing off a merge. First parent is our original
> +    # parent, second is the fake commit we're unshelving.
> +    wlock = repo.wlock()
> +    lock = None
> +    try:
> +        checkparents(repo, state)
> +        ms = merge.mergestate(repo)
> +        if [f for f in ms if ms[f] == 'u']:
> +            raise util.Abort(
> +                _("unresolved conflicts, can't continue"),
> +                hint=_("see 'hg resolve', then 'hg unshelve --continue'"))
> +        dirstate = repo.dirstate
> +        for f in ms:
> +            if dirstate[f] == 'm':
> +                dirstate.normallookup(f)
> +        dirstate._pl = (dirstate._pl[0], nullid)
> +        dirstate._dirty = dirstate._dirtypl = True
> +        lock = repo.lock()
> +        repair.strip(ui, repo, state.stripnodes, backup='none', topic='shelve')
> +        shelvedstate.clear(repo)
> +        unshelvecleanup(ui, repo, state.name, opts)
> +        ui.status(_("unshelve of '%s' complete\n" % state.name))
> +    finally:
> +        lockmod.release(lock, wlock)
> +
> +@command('unshelve',
> +         [('a', 'abort', None,
> +           _('abort an incomplete unshelve operation')),
> +          ('c', 'continue', None,
> +           _('continue an incomplete unshelve operation')),
> +          ('', 'keep', None,
> +           _('save shelved change'))],
> +         _('hg unshelve [SHELVED]'))
> +def unshelve(ui, repo, *shelved, **opts):
> +    '''restore a shelved change to the working directory
> +
> +    This command accepts an optional name of a shelved change to
> +    restore. If none is given, the most recent shelved change is used.
> +
> +    If a shelved change is applied successfully, the bundle that
> +    contains the shelved changes is deleted afterwards.
> +
> +    Since you can restore a shelved change on top of an arbitrary
> +    commit, it is possible that unshelving will result in a conflict
> +    between your changes and the commits you are unshelving onto. If
> +    this occurs, you must resolve the conflict, then use
> +    ``--continue`` to complete the unshelve operation. (The bundle
> +    will not be deleted until you successfully complete the unshelve.)
> +
> +    (Alternatively, you can use ``--abort`` to abandon an unshelve
> +    that causes a conflict. This reverts the unshelved changes, and
> +    does not delete the bundle.)
> +    '''
> +    abortf = opts['abort']
> +    continuef = opts['continue']
> +    if abortf or continuef:
> +        if abortf and continuef:
> +            raise util.Abort(_('cannot use both abort and continue'))
> +        if shelved:
> +            raise util.Abort(_('cannot combine abort/continue with '
> +                               'naming a shelved change'))
> +        try:
> +            state = shelvedstate.load(repo)
> +        except IOError, err:
> +            if err.errno != errno.ENOENT:
> +                raise
> +            raise util.Abort(_('no unshelve operation underway'))
> +
> +        if abortf:
> +            return unshelveabort(ui, repo, state, opts)
> +        elif continuef:
> +            return unshelvecontinue(ui, repo, state, opts)
> +    elif len(shelved) > 1:
> +        raise util.Abort(_('can only unshelve one change at a time'))
> +    elif not shelved:
> +        shelved = listshelves(repo)
> +        if not shelved:
> +            raise util.Abort(_('no shelved changes to apply!'))
> +        basename = os.path.basename(shelved[0][1])
> +        ui.status(_("unshelving change '%s'\n") % basename)
> +    else:
> +        basename = shelved[0]
> +
> +    shelvedfiles = readshelvedfiles(repo, basename)
> +
> +    m, a, r, d = repo.status()[:4]
> +    unsafe = set(m + a + r + d).intersection(shelvedfiles)
> +    if unsafe:
> +        ui.warn(_('the following shelved files have been modified:\n'))
> +        for f in sorted(unsafe):
> +            ui.warn('  %s\n' % f)
> +        ui.warn(_('you must commit, revert, or shelve your changes before you '
> +                  'can proceed\n'))
> +        raise util.Abort(_('cannot unshelve due to local changes\n'))
> +
> +    wlock = lock = None
> +    try:
> +        lock = repo.lock()
> +
> +        oldtiprev = len(repo)
> +        try:
> +            fp = shelvedfile(repo, basename, 'hg')
> +            gen = changegroup.readbundle(fp, fp.name)
> +            modheads = repo.addchangegroup(gen, 'unshelve', 'bundle:' + fp.name)
> +        finally:
> +            fp.close()
> +
> +        tip = repo['tip']
> +        wctx = repo['.']
> +        ancestor = tip.ancestor(wctx)
> +
> +        wlock = repo.wlock()
> +
> +        if ancestor.node() != wctx.node():
> +            conflicts = hg.merge(repo, tip.node(), force=True)
> +            if conflicts:
> +                cl = repo.changelog
> +                shelvedstate.save(repo, basename, oldtiprev)
> +                # Fix up the dirstate entries of files from the second
> +                # parent as if we were not merging, except for those
> +                # with unresolved conflicts.
> +                ms = merge.mergestate(repo)
> +                parents = repo.parents()
> +                revertfiles = set(parents[1].files()).difference(ms)
> +                cmdutil.revert(ui, repo, parents[1],
> +                               (parents[0].node(), nullid),
> +                               *revertfiles, no_backup=True)
> +                raise error.InterventionRequired(
> +                    _("unresolved conflicts (see 'hg resolve', then "
> +                      "'hg unshelve --continue')"))
> +        else:
> +            parent = tip.parents()[0]
> +            hg.update(repo, parent.node())
> +            cmdutil.revert(ui, repo, tip, repo.dirstate.parents(), *tip.files(),
> +                           no_backup=True)
> +            #repair.strip(ui, repo, [tip.node()], backup='none', topic='shelve')
> +
> +            try:
> +                prevquiet = ui.quiet
> +                ui.quiet = True
> +                repo.rollback(force=True)
> +            finally:
> +                ui.quiet = prevquiet
> +
> +        unshelvecleanup(ui, repo, basename, opts)
> +    finally:
> +        lockmod.release(lock, wlock)
> +
> +@command('shelve',
> +         [('A', 'addremove', None,
> +           _('mark new/missing files as added/removed before shelving')),
> +          ('', 'cleanup', None,
> +           _('delete all shelved changes')),
> +          ('', 'date', '',
> +           _('shelve with the specified commit date'), _('DATE')),
> +          ('d', 'delete', None,
> +           _('delete the named shelved change(s)')),
> +          ('l', 'list', None,
> +           _('list current shelves')),
> +          ('m', 'message', '',
> +           _('use text as shelve message'), _('TEXT')),
> +          ('n', 'name', '',
> +           _('use the given name for the shelved commit'), _('NAME')),
> +          ('p', 'patch', None,
> +           _('show patch')),
> +          ('', 'stat', None,
> +           _('output diffstat-style summary of changes'))],
> +         _('hg shelve'))
> +def shelvecmd(ui, repo, *pats, **opts):
> +    '''save and set aside changes from the working directory
> +
> +    Shelving takes files that "hg status" reports as not clean, saves
> +    the modifications to a bundle (a shelved change), and reverts the
> +    files so that their state in the working directory becomes clean.
> +
> +    To restore these changes to the working directory, using "hg
> +    unshelve"; this will work even if you switch to a different
> +    commit.
> +
> +    When no files are specified, "hg shelve" saves all not-clean
> +    files. If specific files or directories are named, only changes to
> +    those files are shelved.
> +
> +    Each shelved change has a name that makes it easier to find later.
> +    The name of a shelved change defaults to being based on the active
> +    bookmark, or if there is no active bookmark, the current named
> +    branch.  To specify a different name, use ``--name``.
> +
> +    To see a list of existing shelved changes, use the ``--list``
> +    option. For each shelved change, this will print its name, age,
> +    and description; use ``--patch`` or ``--stat`` for more details.
> +
> +    To delete specific shelved changes, use ``--delete``. To delete
> +    all shelved changes, use ``--cleanup``.
> +    '''
> +    def checkopt(opt, incompatible):
> +        if opts[opt]:
> +            for i in incompatible.split():
> +                if opts[i]:
> +                    raise util.Abort(_("options '--%s' and '--%s' may not be "
> +                                       "used together") % (opt, i))
> +            return True
> +    if checkopt('cleanup', 'addremove delete list message name patch stat'):
> +        if pats:
> +            raise util.Abort(_("cannot specify names when using '--cleanup'"))
> +        return cleanupcmd(ui, repo)
> +    elif checkopt('delete', 'addremove cleanup list message name patch stat'):
> +        return deletecmd(ui, repo, pats)
> +    elif checkopt('list', 'addremove cleanup delete message name'):
> +        return listcmd(ui, repo, pats, opts)
> +    else:
> +        for i in ('patch', 'stat'):
> +            if opts[i]:
> +                raise util.Abort(_("option '--%s' may not be "
> +                                   "used when shelving a change") % (i,))
> +        return createcmd(ui, repo, pats, opts)
> diff --git a/tests/run-tests.py b/tests/run-tests.py
> --- a/tests/run-tests.py
> +++ b/tests/run-tests.py
> @@ -889,6 +889,7 @@ def runone(options, test):
>     hgrc.write('[defaults]\n')
>     hgrc.write('backout = -d "0 0"\n')
>     hgrc.write('commit = -d "0 0"\n')
> +    hgrc.write('shelve = --date "0 0"\n')
>     hgrc.write('tag = -d "0 0"\n')
>     if options.inotify:
>         hgrc.write('[extensions]\n')
> diff --git a/tests/test-shelve.t b/tests/test-shelve.t
> new file mode 100644
> --- /dev/null
> +++ b/tests/test-shelve.t
> @@ -0,0 +1,354 @@
> +  $ echo "[extensions]" >> $HGRCPATH
> +  $ echo "shelve=" >> $HGRCPATH
> +  $ echo "[defaults]" >> $HGRCPATH
> +  $ echo "diff = --nodates --git" >> $HGRCPATH
> +
> +  $ hg init repo
> +  $ cd repo
> +  $ mkdir a b
> +  $ echo a > a/a
> +  $ echo b > b/b
> +  $ echo c > c
> +  $ echo d > d
> +  $ echo x > x
> +  $ hg addremove -q
> +
> +shelving in an empty repo should bail
> +
> +  $ hg shelve
> +  abort: cannot shelve - repo has no history
> +  [255]
> +
> +  $ hg commit -q -m 'initial commit'
> +
> +  $ hg shelve
> +  nothing changed
> +  [1]
> +
> +shelve a change that we will delete later
> +
> +  $ echo a >> a/a
> +  $ hg shelve
> +  shelved from default (cc01e2b0): initial commit
> +  shelved as default
> +  1 files updated, 0 files merged, 0 files removed, 0 files unresolved
> +
> +set up some more complex changes to shelve
> +
> +  $ echo a >> a/a
> +  $ hg mv b b.rename
> +  moving b/b to b.rename/b
> +  $ hg cp c c.copy
> +  $ hg status -C
> +  M a/a
> +  A b.rename/b
> +    b/b
> +  A c.copy
> +    c
> +  R b/b
> +
> +prevent some foot-shooting
> +
> +  $ hg shelve -n foo/bar
> +  abort: shelved change names may not contain slashes
> +  [255]
> +  $ hg shelve -n .baz
> +  abort: shelved change names may not start with '.'
> +  [255]
> +
> +the common case - no options or filenames
> +
> +  $ hg shelve
> +  shelved from default (cc01e2b0): initial commit
> +  shelved as default-01
> +  2 files updated, 0 files merged, 2 files removed, 0 files unresolved
> +  $ hg status -C
> +
> +ensure that our shelved changes exist
> +
> +  $ hg shelve -l
> +  default-01      [*]    shelved from default (cc01e2b0): initial commit (glob)
> +  default         [*]    shelved from default (cc01e2b0): initial commit (glob)
> +
> +  $ hg shelve -l -p default
> +  default         [*]    shelved from default (cc01e2b0): initial commit (glob)
> +  
> +  diff --git a/a/a b/a/a
> +  --- a/a/a
> +  +++ b/a/a
> +  @@ -1,1 +1,2 @@
> +   a
> +  +a
> +
> +delete our older shelved change
> +
> +  $ hg shelve -d default
> +
> +local edits should prevent a shelved change from applying
> +
> +  $ echo e>>a/a
> +  $ hg unshelve
> +  unshelving change 'default-01'
> +  the following shelved files have been modified:
> +    a/a
> +  you must commit, revert, or shelve your changes before you can proceed
> +  abort: cannot unshelve due to local changes
> +  
> +  [255]
> +
> +  $ hg revert -C a/a
> +
> +apply it and make sure our state is as expected
> +
> +  $ hg unshelve
> +  unshelving change 'default-01'
> +  adding changesets
> +  adding manifests
> +  adding file changes
> +  added 1 changesets with 3 changes to 7 files
> +  0 files updated, 0 files merged, 0 files removed, 0 files unresolved
> +  $ hg status -C
> +  M a/a
> +  A b.rename/b
> +    b/b
> +  A c.copy
> +    c
> +  R b/b
> +  $ hg shelve -l
> +
> +  $ hg unshelve
> +  abort: no shelved changes to apply!
> +  [255]
> +  $ hg unshelve foo
> +  abort: shelved change 'foo' not found
> +  [255]
> +
> +named shelves, specific filenames, and "commit messages" should all work
> +
> +  $ hg status -C
> +  M a/a
> +  A b.rename/b
> +    b/b
> +  A c.copy
> +    c
> +  R b/b
> +  $ hg shelve -q -n wibble -m wat a
> +
> +expect "a" to no longer be present, but status otherwise unchanged
> +
> +  $ hg status -C
> +  A b.rename/b
> +    b/b
> +  A c.copy
> +    c
> +  R b/b
> +  $ hg shelve -l --stat
> +  wibble          [*]    wat (glob)
> +   a/a |  1 +
> +   1 files changed, 1 insertions(+), 0 deletions(-)
> +
> +and now "a/a" should reappear
> +
> +  $ hg unshelve -q wibble
> +  $ hg status -C
> +  M a/a
> +  A b.rename/b
> +    b/b
> +  A c.copy
> +    c
> +  R b/b
> +
> +cause unshelving to result in a merge with 'a' conflicting
> +
> +  $ hg shelve -q
> +  $ echo c>>a/a
> +  $ hg commit -m second
> +  $ hg tip --template '{files}\n'
> +  a/a
> +
> +add an unrelated change that should be preserved
> +
> +  $ mkdir foo
> +  $ echo foo > foo/foo
> +  $ hg add foo/foo
> +
> +force a conflicted merge to occur
> +
> +  $ hg unshelve
> +  unshelving change 'default'
> +  adding changesets
> +  adding manifests
> +  adding file changes
> +  added 1 changesets with 3 changes to 7 files (+1 heads)
> +  merging a/a
> +  warning: conflicts during merge.
> +  merging a/a incomplete! (edit conflicts, then use 'hg resolve --mark')
> +  2 files updated, 0 files merged, 1 files removed, 1 files unresolved
> +  use 'hg resolve' to retry unresolved file merges or 'hg update -C .' to abandon
> +  unresolved conflicts (see 'hg resolve', then 'hg unshelve --continue')
> +  [1]
> +
> +ensure that we have a merge with unresolved conflicts
> +
> +  $ hg heads -q
> +  2:99fa200422e2
> +  1:71743bbd8fc8
> +  $ hg parents -q
> +  1:71743bbd8fc8
> +  2:99fa200422e2
> +  $ hg status
> +  M a/a
> +  M b.rename/b
> +  M c.copy
> +  A foo/foo
> +  R b/b
> +  ? a/a.orig
> +  $ hg diff
> +  diff --git a/a/a b/a/a
> +  --- a/a/a
> +  +++ b/a/a
> +  @@ -1,2 +1,6 @@
> +   a
> +  +<<<<<<< local
> +   c
> +  +=======
> +  +a
> +  +>>>>>>> other
> +  diff --git a/b.rename/b b/b.rename/b
> +  --- /dev/null
> +  +++ b/b.rename/b
> +  @@ -0,0 +1,1 @@
> +  +b
> +  diff --git a/b/b b/b/b
> +  deleted file mode 100644
> +  --- a/b/b
> +  +++ /dev/null
> +  @@ -1,1 +0,0 @@
> +  -b
> +  diff --git a/c.copy b/c.copy
> +  --- /dev/null
> +  +++ b/c.copy
> +  @@ -0,0 +1,1 @@
> +  +c
> +  diff --git a/foo/foo b/foo/foo
> +  new file mode 100644
> +  --- /dev/null
> +  +++ b/foo/foo
> +  @@ -0,0 +1,1 @@
> +  +foo
> +  $ hg resolve -l
> +  U a/a
> +
> +  $ hg shelve
> +  abort: unshelve already in progress
> +  [255]
> +
> +abort the unshelve and be happy
> +
> +  $ hg status
> +  M a/a
> +  M b.rename/b
> +  M c.copy
> +  A foo/foo
> +  R b/b
> +  ? a/a.orig
> +  $ hg unshelve -a
> +  unshelve of 'default' aborted
> +  $ hg heads -q
> +  1:71743bbd8fc8
> +  $ hg parents
> +  changeset:   1:71743bbd8fc8
> +  tag:         tip
> +  user:        test
> +  date:        Thu Jan 01 00:00:00 1970 +0000
> +  summary:     second
> +  
> +  $ hg resolve -l
> +  $ hg status
> +  A foo/foo
> +  ? a/a.orig
> +
> +try to continue with no unshelve underway
> +
> +  $ hg unshelve -c
> +  abort: no unshelve operation underway
> +  [255]
> +  $ hg status
> +  A foo/foo
> +  ? a/a.orig
> +
> +redo the unshelve to get a conflict
> +
> +  $ hg unshelve -q
> +  warning: conflicts during merge.
> +  merging a/a incomplete! (edit conflicts, then use 'hg resolve --mark')
> +  unresolved conflicts (see 'hg resolve', then 'hg unshelve --continue')
> +  [1]
> +
> +attempt to continue
> +
> +  $ hg unshelve -c
> +  abort: unresolved conflicts, can't continue
> +  (see 'hg resolve', then 'hg unshelve --continue')
> +  [255]
> +
> +  $ hg revert -r . a/a
> +  $ hg resolve -m a/a
> +
> +  $ hg unshelve -c
> +  unshelve of 'default' complete
> +
> +ensure the repo is as we hope
> +
> +  $ hg parents
> +  changeset:   1:71743bbd8fc8
> +  tag:         tip
> +  user:        test
> +  date:        Thu Jan 01 00:00:00 1970 +0000
> +  summary:     second
> +  
> +  $ hg heads -q
> +  1:71743bbd8fc8
> +
> +  $ hg status -C
> +  M a/a
> +  M b.rename/b
> +    b/b
> +  M c.copy
> +    c
> +  A foo/foo
> +  R b/b
> +  ? a/a.orig
> +
> +there should be no shelves left
> +
> +  $ hg shelve -l
> +
> +  $ hg commit -m whee a/a
> +
> +#if execbit
> +
> +ensure that metadata-only changes are shelved
> +
> +  $ chmod +x a/a
> +  $ hg shelve -q -n execbit a/a
> +  $ hg status a/a
> +  $ hg unshelve -q execbit
> +  $ hg status a/a
> +  M a/a
> +  $ hg revert a/a
> +
> +#endif
> +
> +#if symlink
> +
> +  $ rm a/a
> +  $ ln -s foo a/a
> +  $ hg shelve -q -n symlink a/a
> +  $ hg status a/a
> +  $ hg unshelve -q symlink
> +  $ hg status a/a
> +  M a/a
> +  $ hg revert a/a
> +
> +#endif
> _______________________________________________
> Mercurial-devel mailing list
> Mercurial-devel@selenic.com
> http://selenic.com/mailman/listinfo/mercurial-devel
Pierre-Yves David - May 29, 2013, 4:19 p.m.
On Tue, May 28, 2013 at 08:20:05PM -0400, Augie Fackler wrote:
> 
> On May 28, 2013, at 7:28 PM, Bryan O'Sullivan <bos@serpentine.com> wrote:
> 
> > # HG changeset patch
> > # User Bryan O'Sullivan <bryano@fb.com>
> > # Date 1369783721 25200
> > #      Tue May 28 16:28:41 2013 -0700
> > # Node ID a87ee920b333192898e8ff84e30ddb1ebac515b6
> > # Parent  11fce4dc68f060e96cc06cc88da72e2c9da1022b
> > shelve: add a shelve extension to save/restore working changes

Sound very similar to the "stash" extension from idan K.

> One code style question.
> 
> I wonder if we shouldn't take a step back and have some central
> registry of things that could be in-progress, since an in-progress
> histedit, merge, rebase, or graft should abort this, and not all of
> those will necessarily look like a merge (and the abort message could
> be confusing).

Ho yes, we should. I have more and more multi step operation and a
generic mecanism to prevent mistake would be very helpful.

In an ideal future we could even have a consistent experience with
global "hg continue" and "hg abort".

> > This extension saves shelved changes using a temporary draft commit,
> > and bundles all draft ancestors of the temporary commit. This
> > strategy makes it possible to use Mercurial's merge machinery to
> > resolve conflicts if necessary when unshelving, even when the
> > destination commit or its ancestors have been amended, squashed,
> > or evolved.

hu, clever!
Bryan O'Sullivan - May 29, 2013, 9 p.m.
On Tue, May 28, 2013 at 4:28 PM, Bryan O'Sullivan <bos@serpentine.com>wrote:

> This extension saves shelved changes using a temporary draft commit,
> and bundles all draft ancestors of the temporary commit.
>

I should clarify: we create a draft commit, bundle it and its draft
ancestors, and then strip the temporary commit. That means that the shelved
commit is not present in history; does not interfere with mq; but still
uses normal Mercurial machinery (including support for merges and
conflicts!) instead of something ad hoc like patches.
Bryan O'Sullivan - May 29, 2013, 10:11 p.m.
On Tue, May 28, 2013 at 5:20 PM, Augie Fackler <raf@durin42.com> wrote:


> I wonder if we shouldn't take a step back and have some central registry
> of things that could be in-progress, since an in-progress histedit, merge,
> rebase, or graft should abort this, and not all of those will necessarily
> look like a merge (and the abort message could be confusing).
>

Definitely. I found myself thinking the same thing on Monday, in fact.

> +def createcmd(ui, repo, pats, opts):
> > +    def publicancestors(ctx):
>
> why is this function nested?


It started out life as a top-level function with an underscore prefix, but
it's only used inside createcmd, so I moved it in there.
Idan Kamara - May 30, 2013, 1:36 p.m.
On Wed, May 29, 2013 at 2:28 AM, Bryan O'Sullivan <bos@serpentine.com>
wrote:
>
> # HG changeset patch
> # User Bryan O'Sullivan <bryano@fb.com>
> # Date 1369783721 25200
> #      Tue May 28 16:28:41 2013 -0700
> # Node ID a87ee920b333192898e8ff84e30ddb1ebac515b6
> # Parent  11fce4dc68f060e96cc06cc88da72e2c9da1022b
> shelve: add a shelve extension to save/restore working changes
>
> This extension saves shelved changes using a temporary draft commit,
> and bundles all draft ancestors of the temporary commit. This
> strategy makes it possible to use Mercurial's merge machinery to
> resolve conflicts if necessary when unshelving, even when the
> destination commit or its ancestors have been amended, squashed,
> or evolved.

Nice, this seems to deal with the issues I had with my implementation.

Are you stripping the temporary commit and its bundled ancestors when an
unshelve succeeds?

>
> Although this extension shares its name and some functionality with
> the third party hgshelve extension, it has little else in common.
> Notably, the hgshelve extension shelves changes as unified diffs,
> which makes conflict resolution a matter of finding .rej files and
> cleaning up the mess by hand.

Won't the name conflict cause issues for existing users of hgshelve? Why
not call it stash?

>
> We do not yet allow hunk-level choosing of changes to record.
> Compared to the hgshelve extension, this is a small regression in
> usability, but we hope to integrate that at a later point, once the
> record machinery becomes more reusable and robust.
>
> diff --git a/hgext/color.py b/hgext/color.py
> --- a/hgext/color.py
> +++ b/hgext/color.py
> @@ -63,6 +63,10 @@ Default effects may be overridden from y
>    rebase.rebased = blue
>    rebase.remaining = red bold
>
> +  shelve.age = cyan
> +  shelve.newest = green bold
> +  shelve.name = blue bold
> +
>    histedit.remaining = red bold
>
>  The available effects in terminfo mode are 'blink', 'bold', 'dim',
> @@ -260,6 +264,9 @@ except ImportError:
>             'rebase.remaining': 'red bold',
>             'resolve.resolved': 'green bold',
>             'resolve.unresolved': 'red bold',
> +           'shelve.age': 'cyan',
> +           'shelve.newest': 'green bold',
> +           'shelve.name': 'blue bold',
>             'status.added': 'green bold',
>             'status.clean': 'none',
>             'status.copied': 'none',
> diff --git a/hgext/shelve.py b/hgext/shelve.py
> new file mode 100644
> --- /dev/null
> +++ b/hgext/shelve.py
> @@ -0,0 +1,552 @@
> +# shelve.py - save/restore working directory state

Does this file pass tests? There are some unused imports and
commented code here.

[..]

> +
> +apply it and make sure our state is as expected
> +
> +  $ hg unshelve
> +  unshelving change 'default-01'
> +  adding changesets
> +  adding manifests
> +  adding file changes
> +  added 1 changesets with 3 changes to 7 files
> +  0 files updated, 0 files merged, 0 files removed, 0 files unresolved

Shouldn't it say 1 files updated here?

> +  $ hg status -C
> +  M a/a
> +  A b.rename/b
> +    b/b
> +  A c.copy
> +    c
> +  R b/b
> +  $ hg shelve -l
Bryan O'Sullivan - May 31, 2013, 11:51 p.m.
On Thu, May 30, 2013 at 6:36 AM, Idan Kamara <idankk86@gmail.com> wrote:

>
> Are you stripping the temporary commit and its bundled ancestors when an
> unshelve succeeds?
>

Yep.


> Won't the name conflict cause issues for existing users of hgshelve? Why
> not call it stash?
>

The extensions have different names, so you won't accidentally get one if
you have the other enabled. I don't see a problem with them providing the
same command names, since I can't imagine someone wanting to use both.


> Does this file pass tests? There are some unused imports and
> commented code here.
>

It passes the new shelve test, but needs a tiny bit of tweaking to pass the
check-code tests.


> > +  $ hg unshelve
> > +  unshelving change 'default-01'
> > +  adding changesets
> > +  adding manifests
> > +  adding file changes
> > +  added 1 changesets with 3 changes to 7 files
> > +  0 files updated, 0 files merged, 0 files removed, 0 files unresolved
>
> Shouldn't it say 1 files updated here?
>

For this particular test, the change being unshelved makes the same change
to a file as the commit it's being unshelved onto - so the result should
indeed be no changes.

Patch

diff --git a/hgext/color.py b/hgext/color.py
--- a/hgext/color.py
+++ b/hgext/color.py
@@ -63,6 +63,10 @@  Default effects may be overridden from y
   rebase.rebased = blue
   rebase.remaining = red bold
 
+  shelve.age = cyan
+  shelve.newest = green bold
+  shelve.name = blue bold
+
   histedit.remaining = red bold
 
 The available effects in terminfo mode are 'blink', 'bold', 'dim',
@@ -260,6 +264,9 @@  except ImportError:
            'rebase.remaining': 'red bold',
            'resolve.resolved': 'green bold',
            'resolve.unresolved': 'red bold',
+           'shelve.age': 'cyan',
+           'shelve.newest': 'green bold',
+           'shelve.name': 'blue bold',
            'status.added': 'green bold',
            'status.clean': 'none',
            'status.copied': 'none',
diff --git a/hgext/shelve.py b/hgext/shelve.py
new file mode 100644
--- /dev/null
+++ b/hgext/shelve.py
@@ -0,0 +1,552 @@ 
+# shelve.py - save/restore working directory state
+#
+# Copyright 2013 Facebook, Inc.
+#
+# This software may be used and distributed according to the terms of the
+# GNU General Public License version 2 or any later version.
+
+'''save and restore changes to the working directory
+
+The "hg shelve" command saves changes made to the working directory
+and reverts those changes, resetting the working directory to a clean
+state.
+
+Later on, the "hg unshelve" command restores the changes saved by "hg
+shelve". Changes can be restored even after updating to a different
+parent, in which case Mercurial's merge machinery will resolve any
+conflicts if necessary.
+
+You can have more than one shelved change outstanding at a time; each
+shelved change has a distinct name. For details, see the help for "hg
+shelve".
+'''
+
+from mercurial.i18n import _
+from mercurial.node import nullid
+from mercurial import changegroup, cmdutil, commands, extensions, pvec, scmutil
+from mercurial import error, hg, mdiff, merge, node, patch, repair, util
+from mercurial import templatefilters
+from mercurial import lock as lockmod
+import errno, os, time
+
+cmdtable = {}
+command = cmdutil.command(cmdtable)
+testedwith = 'internal'
+
+def shelvedfilename(repo, name, filetype):
+    return os.path.join(repo.join('shelved'), name + '.' + filetype)
+
+def shelvedfile(repo, name, filetype, mode='rb'):
+    '''Open a file used for storing data associated with a shelved change.'''
+    try:
+        return open(shelvedfilename(repo, name, filetype), mode)
+    except IOError, err:
+        if err.errno == errno.ENOENT:
+            if mode[0] in 'wa':
+                try:
+                    repo.vfs.mkdir(repo.join('shelved'))
+                    return open(shelvedfilename(repo, name, filetype), mode)
+                except IOError, err:
+                    if err.errno != errno.EEXIST:
+                        raise
+            elif mode[0] =='r':
+                raise util.Abort(_("shelved change '%s' not found") % name)
+        raise
+
+class shelvedstate(object):
+    @classmethod
+    def load(cls, repo):
+        fp = repo.opener('shelvedstate')
+        try:
+            lines = fp.read().splitlines()
+        finally:
+            fp.close()
+        lines.reverse()
+
+        version = lines.pop()
+        obj = cls()
+        obj.name = lines.pop()
+        obj.parents = [node.bin(n) for n in lines.pop().split()]
+        obj.stripnodes = [node.bin(n) for n in lines]
+        return obj
+
+    @staticmethod
+    def save(repo, name, oldtiprev):
+        fp = repo.opener('shelvedstate', 'wb')
+        fp.write('1\n')
+        fp.write(name + '\n')
+        fp.write(' '.join(node.hex(n) for n in repo.dirstate.parents()) + '\n')
+        # save revs that need to be stripped when we are done
+        for rev in xrange(oldtiprev, len(repo)):
+            fp.write(node.hex(repo.changelog.node(rev)) + '\n')
+        fp.close()
+
+    @staticmethod
+    def clear(repo):
+        util.unlinkpath(repo.join('shelvedstate'), ignoremissing=True)
+
+def createcmd(ui, repo, pats, opts):
+    def publicancestors(ctx):
+        '''Compute the heads of the public ancestors of a commit.
+
+        Much faster than the revset heads(ancestors(ctx) - draft())'''
+        seen = set()
+        visit = util.deque()
+        visit.append(ctx)
+        while visit:
+            ctx = visit.popleft()
+            for parent in ctx.parents():
+                rev = parent.rev()
+                if rev not in seen:
+                    seen.add(rev)
+                    if parent.mutable():
+                        visit.append(parent)
+                    else:
+                        yield parent.node()
+
+    try:
+        shelvedstate.load(repo)
+        raise util.Abort(_('unshelve already in progress'))
+    except IOError, err:
+        if err.errno != errno.ENOENT:
+            raise
+
+    wctx = repo[None]
+    parents = wctx.parents()
+    if len(parents) > 1:
+        raise util.Abort(_('cannot shelve while merging'))
+    parent = parents[0]
+    if parent.node() == nullid:
+        raise util.Abort(_('cannot shelve - repo has no history'))
+
+    try:
+        user = repo.ui.username()
+    except util.Abort:
+        user = 'shelve@localhost'
+
+    label = repo._bookmarkcurrent or parent.branch()
+
+    def gennames():
+        yield label
+        for i in xrange(1, 100):
+            yield '%s-%02d' % (label, i)
+
+    shelvedfiles = []
+
+    def commitfunc(ui, repo, message, match, opts):
+        for flist in repo.status(match=match)[:4]:
+            shelvedfiles.extend(flist)
+        return repo.commit(message, user, opts.get('date'), match)
+
+    desc = parent.description().split('\n', 1)[0]
+    desc = _('shelved from %s (%s): %s') % (label, str(parent)[:8], desc)
+
+    if not opts['message']:
+        opts['message'] = desc
+
+    name = opts['name']
+    if '/' in name or '\\' in name:
+        raise util.Abort(_('shelved change names may not contain slashes'))
+    if name.startswith('.'):
+        raise util.Abort(_("shelved change names may not start with '.'"))
+    if name:
+        if os.path.exists(shelvedfilename(repo, name, 'hg')):
+            raise util.Abort(_("a shelved change named '%s' already exists")
+                             % name)
+
+    wlock = lock = None
+    try:
+        wlock = repo.wlock()
+        lock = repo.lock()
+
+        if not name:
+            for name in gennames():
+                if not os.path.exists(shelvedfilename(repo, name, 'hg')):
+                    break
+            else:
+                raise util.Abort(_("too many shelved changes named '%s'") %
+                                 label)
+
+        node = cmdutil.commit(ui, repo, commitfunc, pats, opts)
+
+        if not node:
+            stat = repo.status(match=scmutil.match(repo[None], pats, opts))
+            if stat[3]:
+                ui.status(_("nothing changed (%d missing files, see "
+                            "'hg status')\n") % len(stat[3]))
+            else:
+                ui.status(_("nothing changed\n"))
+            return 1
+
+        shelvedfile(repo, name, 'files', 'wb').write('\0'.join(shelvedfiles))
+
+        bases = list(publicancestors(repo[node]))
+        cg = repo.changegroupsubset(bases, [node], 'shelve')
+        changegroup.writebundle(cg, shelvedfilename(repo, name, 'hg'),
+                                'HG10UN')
+        cmdutil.export(repo, [node],
+                       fp=shelvedfile(repo, name, 'patch', 'wb'),
+                       opts=mdiff.diffopts(git=True))
+
+        if ui.formatted():
+            desc = util.ellipsis(desc, ui.termwidth())
+        ui.status(desc + '\n')
+        ui.status(_('shelved as %s\n') % name)
+        hg.update(repo, parent.node())
+        repair.strip(ui, repo, [node], backup='none', topic='shelve')
+    finally:
+        lockmod.release(lock, wlock)
+
+def cleanupcmd(ui, repo):
+    path = repo.join('shelved')
+    wlock = None
+    try:
+        wlock = repo.wlock()
+        for name in os.listdir(path):
+            suffix = name.rsplit('.', 1)[-1]
+            if suffix in ('hg', 'files', 'patch'):
+                os.unlink(os.path.join(path, name))
+    finally:
+        lockmod.release(wlock)
+
+def deletecmd(ui, repo, pats):
+    if not pats:
+        raise util.Abort(_('no shelved changes specified!'))
+    wlock = None
+    try:
+        wlock = repo.wlock()
+        try:
+            for name in pats:
+                for suffix in 'hg files patch'.split():
+                    os.unlink(shelvedfilename(repo, name, suffix))
+        except OSError, err:
+            if err.errno != errno.ENOENT:
+                raise
+            raise util.Abort(_("shelved change '%s' not found") % name)
+    finally:
+        lockmod.release(wlock)
+
+def listshelves(repo):
+    path = repo.join('shelved')
+    try:
+        names = os.listdir(path)
+    except OSError, err:
+        if err.errno != errno.ENOENT:
+            raise
+        return []
+    info = []
+    for name in names:
+        pfx, sfx = name.rsplit('.', 1)
+        if not pfx or sfx != 'patch':
+            continue
+        st = os.lstat(os.path.join(path, name))
+        info.append((st.st_mtime, os.path.join(path, pfx)))
+    return sorted(info, reverse=True)
+
+def listcmd(ui, repo, pats, opts):
+    pats = set(pats)
+    width = 80
+    if not ui.plain():
+        width = ui.termwidth()
+    namelabel = 'shelve.newest'
+    for mtime, name in listshelves(repo):
+        sname = os.path.basename(name)
+        if pats and sname not in pats:
+            continue
+        ui.write(sname, label=namelabel)
+        namelabel = 'shelve.name'
+        if ui.quiet:
+            ui.write('\n')
+            continue
+        ui.write(' ' * (16 - len(sname)))
+        used = 16
+        age = '[%s]' % templatefilters.age(util.makedate(mtime))
+        ui.write(age, label='shelve.age')
+        ui.write(' ' * (18 - len(age)))
+        used += 18
+        fp = open(name + '.patch', 'rb')
+        try:
+            while True:
+                line = fp.readline()
+                if not line:
+                    break
+                if not line.startswith('#'):
+                    desc = line.rstrip()
+                    if ui.formatted():
+                        desc = util.ellipsis(desc, width - used)
+                    ui.write(desc)
+                    break
+            ui.write('\n')
+            if not (opts['patch'] or opts['stat']):
+                continue
+            difflines = fp.readlines()
+            if opts['patch']:
+                for chunk, label in patch.difflabel(iter, difflines):
+                    ui.write(chunk, label=label)
+            if opts['stat']:
+                for chunk, label in patch.diffstatui(difflines, width=width,
+                                                     git=True):
+                    ui.write(chunk, label=label)
+        finally:
+            fp.close()
+
+def readshelvedfiles(repo, basename):
+    return shelvedfile(repo, basename, 'files').read().split('\0')
+
+def checkparents(repo, state):
+    if state.parents != repo.dirstate.parents():
+        raise util.Abort(_('working directory parents do not match unshelve '
+                           'state'))
+
+def unshelveabort(ui, repo, state, opts):
+    wlock = repo.wlock()
+    lock = None
+    try:
+        checkparents(repo, state)
+        lock = repo.lock()
+        merge.mergestate(repo).reset()
+        if opts['keep']:
+            repo.setparents(repo.dirstate.parents()[0])
+        else:
+            revertfiles = readshelvedfiles(repo, state.name)
+            wctx = repo.parents()[0]
+            cmdutil.revert(ui, repo, wctx, [wctx.node(), nullid],
+                           *revertfiles, no_backup=True)
+            # fix up the weird dirstate states the merge left behind
+            mf = wctx.manifest()
+            dirstate = repo.dirstate
+            for f in revertfiles:
+                if f in mf:
+                    dirstate.normallookup(f)
+                else:
+                    dirstate.drop(f)
+            dirstate._pl = (wctx.node(), nullid)
+            dirstate._dirty = True
+        repair.strip(ui, repo, state.stripnodes, backup='none', topic='shelve')
+        shelvedstate.clear(repo)
+        ui.warn(_("unshelve of '%s' aborted\n" % state.name))
+    finally:
+        lockmod.release(lock, wlock)
+
+def unshelvecleanup(ui, repo, name, opts):
+    if not opts['keep']:
+        for filetype in 'hg files patch'.split():
+            os.unlink(shelvedfilename(repo, name, filetype))
+
+def unshelvecontinue(ui, repo, state, opts):
+    # We're finishing off a merge. First parent is our original
+    # parent, second is the fake commit we're unshelving.
+    wlock = repo.wlock()
+    lock = None
+    try:
+        checkparents(repo, state)
+        ms = merge.mergestate(repo)
+        if [f for f in ms if ms[f] == 'u']:
+            raise util.Abort(
+                _("unresolved conflicts, can't continue"),
+                hint=_("see 'hg resolve', then 'hg unshelve --continue'"))
+        dirstate = repo.dirstate
+        for f in ms:
+            if dirstate[f] == 'm':
+                dirstate.normallookup(f)
+        dirstate._pl = (dirstate._pl[0], nullid)
+        dirstate._dirty = dirstate._dirtypl = True
+        lock = repo.lock()
+        repair.strip(ui, repo, state.stripnodes, backup='none', topic='shelve')
+        shelvedstate.clear(repo)
+        unshelvecleanup(ui, repo, state.name, opts)
+        ui.status(_("unshelve of '%s' complete\n" % state.name))
+    finally:
+        lockmod.release(lock, wlock)
+
+@command('unshelve',
+         [('a', 'abort', None,
+           _('abort an incomplete unshelve operation')),
+          ('c', 'continue', None,
+           _('continue an incomplete unshelve operation')),
+          ('', 'keep', None,
+           _('save shelved change'))],
+         _('hg unshelve [SHELVED]'))
+def unshelve(ui, repo, *shelved, **opts):
+    '''restore a shelved change to the working directory
+
+    This command accepts an optional name of a shelved change to
+    restore. If none is given, the most recent shelved change is used.
+
+    If a shelved change is applied successfully, the bundle that
+    contains the shelved changes is deleted afterwards.
+
+    Since you can restore a shelved change on top of an arbitrary
+    commit, it is possible that unshelving will result in a conflict
+    between your changes and the commits you are unshelving onto. If
+    this occurs, you must resolve the conflict, then use
+    ``--continue`` to complete the unshelve operation. (The bundle
+    will not be deleted until you successfully complete the unshelve.)
+
+    (Alternatively, you can use ``--abort`` to abandon an unshelve
+    that causes a conflict. This reverts the unshelved changes, and
+    does not delete the bundle.)
+    '''
+    abortf = opts['abort']
+    continuef = opts['continue']
+    if abortf or continuef:
+        if abortf and continuef:
+            raise util.Abort(_('cannot use both abort and continue'))
+        if shelved:
+            raise util.Abort(_('cannot combine abort/continue with '
+                               'naming a shelved change'))
+        try:
+            state = shelvedstate.load(repo)
+        except IOError, err:
+            if err.errno != errno.ENOENT:
+                raise
+            raise util.Abort(_('no unshelve operation underway'))
+
+        if abortf:
+            return unshelveabort(ui, repo, state, opts)
+        elif continuef:
+            return unshelvecontinue(ui, repo, state, opts)
+    elif len(shelved) > 1:
+        raise util.Abort(_('can only unshelve one change at a time'))
+    elif not shelved:
+        shelved = listshelves(repo)
+        if not shelved:
+            raise util.Abort(_('no shelved changes to apply!'))
+        basename = os.path.basename(shelved[0][1])
+        ui.status(_("unshelving change '%s'\n") % basename)
+    else:
+        basename = shelved[0]
+
+    shelvedfiles = readshelvedfiles(repo, basename)
+
+    m, a, r, d = repo.status()[:4]
+    unsafe = set(m + a + r + d).intersection(shelvedfiles)
+    if unsafe:
+        ui.warn(_('the following shelved files have been modified:\n'))
+        for f in sorted(unsafe):
+            ui.warn('  %s\n' % f)
+        ui.warn(_('you must commit, revert, or shelve your changes before you '
+                  'can proceed\n'))
+        raise util.Abort(_('cannot unshelve due to local changes\n'))
+
+    wlock = lock = None
+    try:
+        lock = repo.lock()
+
+        oldtiprev = len(repo)
+        try:
+            fp = shelvedfile(repo, basename, 'hg')
+            gen = changegroup.readbundle(fp, fp.name)
+            modheads = repo.addchangegroup(gen, 'unshelve', 'bundle:' + fp.name)
+        finally:
+            fp.close()
+
+        tip = repo['tip']
+        wctx = repo['.']
+        ancestor = tip.ancestor(wctx)
+
+        wlock = repo.wlock()
+
+        if ancestor.node() != wctx.node():
+            conflicts = hg.merge(repo, tip.node(), force=True)
+            if conflicts:
+                cl = repo.changelog
+                shelvedstate.save(repo, basename, oldtiprev)
+                # Fix up the dirstate entries of files from the second
+                # parent as if we were not merging, except for those
+                # with unresolved conflicts.
+                ms = merge.mergestate(repo)
+                parents = repo.parents()
+                revertfiles = set(parents[1].files()).difference(ms)
+                cmdutil.revert(ui, repo, parents[1],
+                               (parents[0].node(), nullid),
+                               *revertfiles, no_backup=True)
+                raise error.InterventionRequired(
+                    _("unresolved conflicts (see 'hg resolve', then "
+                      "'hg unshelve --continue')"))
+        else:
+            parent = tip.parents()[0]
+            hg.update(repo, parent.node())
+            cmdutil.revert(ui, repo, tip, repo.dirstate.parents(), *tip.files(),
+                           no_backup=True)
+            #repair.strip(ui, repo, [tip.node()], backup='none', topic='shelve')
+
+            try:
+                prevquiet = ui.quiet
+                ui.quiet = True
+                repo.rollback(force=True)
+            finally:
+                ui.quiet = prevquiet
+
+        unshelvecleanup(ui, repo, basename, opts)
+    finally:
+        lockmod.release(lock, wlock)
+
+@command('shelve',
+         [('A', 'addremove', None,
+           _('mark new/missing files as added/removed before shelving')),
+          ('', 'cleanup', None,
+           _('delete all shelved changes')),
+          ('', 'date', '',
+           _('shelve with the specified commit date'), _('DATE')),
+          ('d', 'delete', None,
+           _('delete the named shelved change(s)')),
+          ('l', 'list', None,
+           _('list current shelves')),
+          ('m', 'message', '',
+           _('use text as shelve message'), _('TEXT')),
+          ('n', 'name', '',
+           _('use the given name for the shelved commit'), _('NAME')),
+          ('p', 'patch', None,
+           _('show patch')),
+          ('', 'stat', None,
+           _('output diffstat-style summary of changes'))],
+         _('hg shelve'))
+def shelvecmd(ui, repo, *pats, **opts):
+    '''save and set aside changes from the working directory
+
+    Shelving takes files that "hg status" reports as not clean, saves
+    the modifications to a bundle (a shelved change), and reverts the
+    files so that their state in the working directory becomes clean.
+
+    To restore these changes to the working directory, using "hg
+    unshelve"; this will work even if you switch to a different
+    commit.
+
+    When no files are specified, "hg shelve" saves all not-clean
+    files. If specific files or directories are named, only changes to
+    those files are shelved.
+
+    Each shelved change has a name that makes it easier to find later.
+    The name of a shelved change defaults to being based on the active
+    bookmark, or if there is no active bookmark, the current named
+    branch.  To specify a different name, use ``--name``.
+
+    To see a list of existing shelved changes, use the ``--list``
+    option. For each shelved change, this will print its name, age,
+    and description; use ``--patch`` or ``--stat`` for more details.
+
+    To delete specific shelved changes, use ``--delete``. To delete
+    all shelved changes, use ``--cleanup``.
+    '''
+    def checkopt(opt, incompatible):
+        if opts[opt]:
+            for i in incompatible.split():
+                if opts[i]:
+                    raise util.Abort(_("options '--%s' and '--%s' may not be "
+                                       "used together") % (opt, i))
+            return True
+    if checkopt('cleanup', 'addremove delete list message name patch stat'):
+        if pats:
+            raise util.Abort(_("cannot specify names when using '--cleanup'"))
+        return cleanupcmd(ui, repo)
+    elif checkopt('delete', 'addremove cleanup list message name patch stat'):
+        return deletecmd(ui, repo, pats)
+    elif checkopt('list', 'addremove cleanup delete message name'):
+        return listcmd(ui, repo, pats, opts)
+    else:
+        for i in ('patch', 'stat'):
+            if opts[i]:
+                raise util.Abort(_("option '--%s' may not be "
+                                   "used when shelving a change") % (i,))
+        return createcmd(ui, repo, pats, opts)
diff --git a/tests/run-tests.py b/tests/run-tests.py
--- a/tests/run-tests.py
+++ b/tests/run-tests.py
@@ -889,6 +889,7 @@  def runone(options, test):
     hgrc.write('[defaults]\n')
     hgrc.write('backout = -d "0 0"\n')
     hgrc.write('commit = -d "0 0"\n')
+    hgrc.write('shelve = --date "0 0"\n')
     hgrc.write('tag = -d "0 0"\n')
     if options.inotify:
         hgrc.write('[extensions]\n')
diff --git a/tests/test-shelve.t b/tests/test-shelve.t
new file mode 100644
--- /dev/null
+++ b/tests/test-shelve.t
@@ -0,0 +1,354 @@ 
+  $ echo "[extensions]" >> $HGRCPATH
+  $ echo "shelve=" >> $HGRCPATH
+  $ echo "[defaults]" >> $HGRCPATH
+  $ echo "diff = --nodates --git" >> $HGRCPATH
+
+  $ hg init repo
+  $ cd repo
+  $ mkdir a b
+  $ echo a > a/a
+  $ echo b > b/b
+  $ echo c > c
+  $ echo d > d
+  $ echo x > x
+  $ hg addremove -q
+
+shelving in an empty repo should bail
+
+  $ hg shelve
+  abort: cannot shelve - repo has no history
+  [255]
+
+  $ hg commit -q -m 'initial commit'
+
+  $ hg shelve
+  nothing changed
+  [1]
+
+shelve a change that we will delete later
+
+  $ echo a >> a/a
+  $ hg shelve
+  shelved from default (cc01e2b0): initial commit
+  shelved as default
+  1 files updated, 0 files merged, 0 files removed, 0 files unresolved
+
+set up some more complex changes to shelve
+
+  $ echo a >> a/a
+  $ hg mv b b.rename
+  moving b/b to b.rename/b
+  $ hg cp c c.copy
+  $ hg status -C
+  M a/a
+  A b.rename/b
+    b/b
+  A c.copy
+    c
+  R b/b
+
+prevent some foot-shooting
+
+  $ hg shelve -n foo/bar
+  abort: shelved change names may not contain slashes
+  [255]
+  $ hg shelve -n .baz
+  abort: shelved change names may not start with '.'
+  [255]
+
+the common case - no options or filenames
+
+  $ hg shelve
+  shelved from default (cc01e2b0): initial commit
+  shelved as default-01
+  2 files updated, 0 files merged, 2 files removed, 0 files unresolved
+  $ hg status -C
+
+ensure that our shelved changes exist
+
+  $ hg shelve -l
+  default-01      [*]    shelved from default (cc01e2b0): initial commit (glob)
+  default         [*]    shelved from default (cc01e2b0): initial commit (glob)
+
+  $ hg shelve -l -p default
+  default         [*]    shelved from default (cc01e2b0): initial commit (glob)
+  
+  diff --git a/a/a b/a/a
+  --- a/a/a
+  +++ b/a/a
+  @@ -1,1 +1,2 @@
+   a
+  +a
+
+delete our older shelved change
+
+  $ hg shelve -d default
+
+local edits should prevent a shelved change from applying
+
+  $ echo e>>a/a
+  $ hg unshelve
+  unshelving change 'default-01'
+  the following shelved files have been modified:
+    a/a
+  you must commit, revert, or shelve your changes before you can proceed
+  abort: cannot unshelve due to local changes
+  
+  [255]
+
+  $ hg revert -C a/a
+
+apply it and make sure our state is as expected
+
+  $ hg unshelve
+  unshelving change 'default-01'
+  adding changesets
+  adding manifests
+  adding file changes
+  added 1 changesets with 3 changes to 7 files
+  0 files updated, 0 files merged, 0 files removed, 0 files unresolved
+  $ hg status -C
+  M a/a
+  A b.rename/b
+    b/b
+  A c.copy
+    c
+  R b/b
+  $ hg shelve -l
+
+  $ hg unshelve
+  abort: no shelved changes to apply!
+  [255]
+  $ hg unshelve foo
+  abort: shelved change 'foo' not found
+  [255]
+
+named shelves, specific filenames, and "commit messages" should all work
+
+  $ hg status -C
+  M a/a
+  A b.rename/b
+    b/b
+  A c.copy
+    c
+  R b/b
+  $ hg shelve -q -n wibble -m wat a
+
+expect "a" to no longer be present, but status otherwise unchanged
+
+  $ hg status -C
+  A b.rename/b
+    b/b
+  A c.copy
+    c
+  R b/b
+  $ hg shelve -l --stat
+  wibble          [*]    wat (glob)
+   a/a |  1 +
+   1 files changed, 1 insertions(+), 0 deletions(-)
+
+and now "a/a" should reappear
+
+  $ hg unshelve -q wibble
+  $ hg status -C
+  M a/a
+  A b.rename/b
+    b/b
+  A c.copy
+    c
+  R b/b
+
+cause unshelving to result in a merge with 'a' conflicting
+
+  $ hg shelve -q
+  $ echo c>>a/a
+  $ hg commit -m second
+  $ hg tip --template '{files}\n'
+  a/a
+
+add an unrelated change that should be preserved
+
+  $ mkdir foo
+  $ echo foo > foo/foo
+  $ hg add foo/foo
+
+force a conflicted merge to occur
+
+  $ hg unshelve
+  unshelving change 'default'
+  adding changesets
+  adding manifests
+  adding file changes
+  added 1 changesets with 3 changes to 7 files (+1 heads)
+  merging a/a
+  warning: conflicts during merge.
+  merging a/a incomplete! (edit conflicts, then use 'hg resolve --mark')
+  2 files updated, 0 files merged, 1 files removed, 1 files unresolved
+  use 'hg resolve' to retry unresolved file merges or 'hg update -C .' to abandon
+  unresolved conflicts (see 'hg resolve', then 'hg unshelve --continue')
+  [1]
+
+ensure that we have a merge with unresolved conflicts
+
+  $ hg heads -q
+  2:99fa200422e2
+  1:71743bbd8fc8
+  $ hg parents -q
+  1:71743bbd8fc8
+  2:99fa200422e2
+  $ hg status
+  M a/a
+  M b.rename/b
+  M c.copy
+  A foo/foo
+  R b/b
+  ? a/a.orig
+  $ hg diff
+  diff --git a/a/a b/a/a
+  --- a/a/a
+  +++ b/a/a
+  @@ -1,2 +1,6 @@
+   a
+  +<<<<<<< local
+   c
+  +=======
+  +a
+  +>>>>>>> other
+  diff --git a/b.rename/b b/b.rename/b
+  --- /dev/null
+  +++ b/b.rename/b
+  @@ -0,0 +1,1 @@
+  +b
+  diff --git a/b/b b/b/b
+  deleted file mode 100644
+  --- a/b/b
+  +++ /dev/null
+  @@ -1,1 +0,0 @@
+  -b
+  diff --git a/c.copy b/c.copy
+  --- /dev/null
+  +++ b/c.copy
+  @@ -0,0 +1,1 @@
+  +c
+  diff --git a/foo/foo b/foo/foo
+  new file mode 100644
+  --- /dev/null
+  +++ b/foo/foo
+  @@ -0,0 +1,1 @@
+  +foo
+  $ hg resolve -l
+  U a/a
+
+  $ hg shelve
+  abort: unshelve already in progress
+  [255]
+
+abort the unshelve and be happy
+
+  $ hg status
+  M a/a
+  M b.rename/b
+  M c.copy
+  A foo/foo
+  R b/b
+  ? a/a.orig
+  $ hg unshelve -a
+  unshelve of 'default' aborted
+  $ hg heads -q
+  1:71743bbd8fc8
+  $ hg parents
+  changeset:   1:71743bbd8fc8
+  tag:         tip
+  user:        test
+  date:        Thu Jan 01 00:00:00 1970 +0000
+  summary:     second
+  
+  $ hg resolve -l
+  $ hg status
+  A foo/foo
+  ? a/a.orig
+
+try to continue with no unshelve underway
+
+  $ hg unshelve -c
+  abort: no unshelve operation underway
+  [255]
+  $ hg status
+  A foo/foo
+  ? a/a.orig
+
+redo the unshelve to get a conflict
+
+  $ hg unshelve -q
+  warning: conflicts during merge.
+  merging a/a incomplete! (edit conflicts, then use 'hg resolve --mark')
+  unresolved conflicts (see 'hg resolve', then 'hg unshelve --continue')
+  [1]
+
+attempt to continue
+
+  $ hg unshelve -c
+  abort: unresolved conflicts, can't continue
+  (see 'hg resolve', then 'hg unshelve --continue')
+  [255]
+
+  $ hg revert -r . a/a
+  $ hg resolve -m a/a
+
+  $ hg unshelve -c
+  unshelve of 'default' complete
+
+ensure the repo is as we hope
+
+  $ hg parents
+  changeset:   1:71743bbd8fc8
+  tag:         tip
+  user:        test
+  date:        Thu Jan 01 00:00:00 1970 +0000
+  summary:     second
+  
+  $ hg heads -q
+  1:71743bbd8fc8
+
+  $ hg status -C
+  M a/a
+  M b.rename/b
+    b/b
+  M c.copy
+    c
+  A foo/foo
+  R b/b
+  ? a/a.orig
+
+there should be no shelves left
+
+  $ hg shelve -l
+
+  $ hg commit -m whee a/a
+
+#if execbit
+
+ensure that metadata-only changes are shelved
+
+  $ chmod +x a/a
+  $ hg shelve -q -n execbit a/a
+  $ hg status a/a
+  $ hg unshelve -q execbit
+  $ hg status a/a
+  M a/a
+  $ hg revert a/a
+
+#endif
+
+#if symlink
+
+  $ rm a/a
+  $ ln -s foo a/a
+  $ hg shelve -q -n symlink a/a
+  $ hg status a/a
+  $ hg unshelve -q symlink
+  $ hg status a/a
+  M a/a
+  $ hg revert a/a
+
+#endif