git: skeleton of a new extension to _directly_ operate on git repos
This is based in part of work I did years ago in hgit, but it's mostly
new code since I'm using pygit2 instead of dulwich and the hg storage
interfaces have improved. Some cleanup of old hgit code by Pulkit,
which I greatly appreciate.
test-git-interop.t does not cover a whole lot of cases, but it
passes. It includes status, diff, making a new commit, and `hg annotate`
working on the git repository.
This is _not_ (yet) production quality code: this is an
experiment. Known technical debt lurking in this implementation:
* Writing bookmarks just totally ignores transactions.
* The way progress is threaded down into the gitstore is awful.
* Ideally we'd find a way to incrementally reindex DAGs. I'm not sure
how to do that efficiently, so we might need a "known only fast-forwards"
mode on the DAG indexer for use on `hg commit` and friends.
* We don't even _try_ to do anything reasonable for `hg pull` or `hg push`.
* Mercurial need an interface for the changelog type.
Tests currently require git 2.24 as far as I'm aware: `git status` has
some changed output that I didn't try and handle in a compatible way.
This patch has produced some interesting cleanups, most recently on
the manifest type. I expect continuing down this road will produce
other meritorious cleanups throughout our code.
Differential Revision: https://phab.mercurial-scm.org/D6734
"""strip changesets and their descendants from history
This extension allows you to strip changesets and all their descendants from the
repository. See the command help for details.
"""
from __future__ import absolute_import
from mercurial.i18n import _
from mercurial.pycompat import getattr
from mercurial import (
bookmarks as bookmarksmod,
cmdutil,
error,
hg,
lock as lockmod,
merge,
node as nodemod,
pycompat,
registrar,
repair,
scmutil,
util,
)
nullid = nodemod.nullid
release = lockmod.release
cmdtable = {}
command = registrar.command(cmdtable)
# Note for extension authors: ONLY specify testedwith = 'ships-with-hg-core' for
# extensions which SHIP WITH MERCURIAL. Non-mainline extensions should
# be specifying the version(s) of Mercurial they are tested with, or
# leave the attribute unspecified.
testedwith = b'ships-with-hg-core'
def checklocalchanges(repo, force=False):
s = repo.status()
if not force:
cmdutil.checkunfinished(repo)
cmdutil.bailifchanged(repo)
else:
cmdutil.checkunfinished(repo, skipmerge=True)
return s
def _findupdatetarget(repo, nodes):
unode, p2 = repo.changelog.parents(nodes[0])
currentbranch = repo[None].branch()
if (
util.safehasattr(repo, b'mq')
and p2 != nullid
and p2 in [x.node for x in repo.mq.applied]
):
unode = p2
elif currentbranch != repo[unode].branch():
pwdir = b'parents(wdir())'
revset = b'max(((parents(%ln::%r) + %r) - %ln::%r) and branch(%s))'
branchtarget = repo.revs(
revset, nodes, pwdir, pwdir, nodes, pwdir, currentbranch
)
if branchtarget:
cl = repo.changelog
unode = cl.node(branchtarget.first())
return unode
def strip(
ui,
repo,
revs,
update=True,
backup=True,
force=None,
bookmarks=None,
soft=False,
):
with repo.wlock(), repo.lock():
if update:
checklocalchanges(repo, force=force)
urev = _findupdatetarget(repo, revs)
hg.clean(repo, urev)
repo.dirstate.write(repo.currenttransaction())
if soft:
repair.softstrip(ui, repo, revs, backup)
else:
repair.strip(ui, repo, revs, backup)
repomarks = repo._bookmarks
if bookmarks:
with repo.transaction(b'strip') as tr:
if repo._activebookmark in bookmarks:
bookmarksmod.deactivate(repo)
repomarks.applychanges(repo, tr, [(b, None) for b in bookmarks])
for bookmark in sorted(bookmarks):
ui.write(_(b"bookmark '%s' deleted\n") % bookmark)
@command(
b"strip",
[
(
b'r',
b'rev',
[],
_(
b'strip specified revision (optional, '
b'can specify revisions without this '
b'option)'
),
_(b'REV'),
),
(
b'f',
b'force',
None,
_(
b'force removal of changesets, discard '
b'uncommitted changes (no backup)'
),
),
(b'', b'no-backup', None, _(b'do not save backup bundle')),
(b'', b'nobackup', None, _(b'do not save backup bundle (DEPRECATED)'),),
(b'n', b'', None, _(b'ignored (DEPRECATED)')),
(
b'k',
b'keep',
None,
_(b"do not modify working directory during strip"),
),
(
b'B',
b'bookmark',
[],
_(b"remove revs only reachable from given bookmark"),
_(b'BOOKMARK'),
),
(
b'',
b'soft',
None,
_(b"simply drop changesets from visible history (EXPERIMENTAL)"),
),
],
_(b'hg strip [-k] [-f] [-B bookmark] [-r] REV...'),
helpcategory=command.CATEGORY_MAINTENANCE,
)
def stripcmd(ui, repo, *revs, **opts):
"""strip changesets and all their descendants from the repository
The strip command removes the specified changesets and all their
descendants. If the working directory has uncommitted changes, the
operation is aborted unless the --force flag is supplied, in which
case changes will be discarded.
If a parent of the working directory is stripped, then the working
directory will automatically be updated to the most recent
available ancestor of the stripped parent after the operation
completes.
Any stripped changesets are stored in ``.hg/strip-backup`` as a
bundle (see :hg:`help bundle` and :hg:`help unbundle`). They can
be restored by running :hg:`unbundle .hg/strip-backup/BUNDLE`,
where BUNDLE is the bundle file created by the strip. Note that
the local revision numbers will in general be different after the
restore.
Use the --no-backup option to discard the backup bundle once the
operation completes.
Strip is not a history-rewriting operation and can be used on
changesets in the public phase. But if the stripped changesets have
been pushed to a remote repository you will likely pull them again.
Return 0 on success.
"""
opts = pycompat.byteskwargs(opts)
backup = True
if opts.get(b'no_backup') or opts.get(b'nobackup'):
backup = False
cl = repo.changelog
revs = list(revs) + opts.get(b'rev')
revs = set(scmutil.revrange(repo, revs))
with repo.wlock():
bookmarks = set(opts.get(b'bookmark'))
if bookmarks:
repomarks = repo._bookmarks
if not bookmarks.issubset(repomarks):
raise error.Abort(
_(b"bookmark '%s' not found")
% b','.join(sorted(bookmarks - set(repomarks.keys())))
)
# If the requested bookmark is not the only one pointing to a
# a revision we have to only delete the bookmark and not strip
# anything. revsets cannot detect that case.
nodetobookmarks = {}
for mark, node in pycompat.iteritems(repomarks):
nodetobookmarks.setdefault(node, []).append(mark)
for marks in nodetobookmarks.values():
if bookmarks.issuperset(marks):
rsrevs = scmutil.bookmarkrevs(repo, marks[0])
revs.update(set(rsrevs))
if not revs:
with repo.lock(), repo.transaction(b'bookmark') as tr:
bmchanges = [(b, None) for b in bookmarks]
repomarks.applychanges(repo, tr, bmchanges)
for bookmark in sorted(bookmarks):
ui.write(_(b"bookmark '%s' deleted\n") % bookmark)
if not revs:
raise error.Abort(_(b'empty revision set'))
descendants = set(cl.descendants(revs))
strippedrevs = revs.union(descendants)
roots = revs.difference(descendants)
# if one of the wdir parent is stripped we'll need
# to update away to an earlier revision
update = any(
p != nullid and cl.rev(p) in strippedrevs
for p in repo.dirstate.parents()
)
rootnodes = {cl.node(r) for r in roots}
q = getattr(repo, 'mq', None)
if q is not None and q.applied:
# refresh queue state if we're about to strip
# applied patches
if cl.rev(repo.lookup(b'qtip')) in strippedrevs:
q.applieddirty = True
start = 0
end = len(q.applied)
for i, statusentry in enumerate(q.applied):
if statusentry.node in rootnodes:
# if one of the stripped roots is an applied
# patch, only part of the queue is stripped
start = i
break
del q.applied[start:end]
q.savedirty()
revs = sorted(rootnodes)
if update and opts.get(b'keep'):
urev = _findupdatetarget(repo, revs)
uctx = repo[urev]
# only reset the dirstate for files that would actually change
# between the working context and uctx
descendantrevs = repo.revs(b"%d::.", uctx.rev())
changedfiles = []
for rev in descendantrevs:
# blindly reset the files, regardless of what actually changed
changedfiles.extend(repo[rev].files())
# reset files that only changed in the dirstate too
dirstate = repo.dirstate
dirchanges = [f for f in dirstate if dirstate[f] != b'n']
changedfiles.extend(dirchanges)
repo.dirstate.rebuild(urev, uctx.manifest(), changedfiles)
repo.dirstate.write(repo.currenttransaction())
# clear resolve state
merge.mergestate.clean(repo, repo[b'.'].node())
update = False
strip(
ui,
repo,
revs,
backup=backup,
update=update,
force=opts.get(b'force'),
bookmarks=bookmarks,
soft=opts[b'soft'],
)
return 0