mercurial/strip.py
author Pierre-Yves David <pierre-yves.david@octobus.net>
Thu, 23 Feb 2023 15:37:46 +0100
changeset 50195 11e6eee4b063
parent 50112 62158471d038
child 50603 d1502345f89c
permissions -rw-r--r--
transaction: use the standard transaction mechanism to backup branch Branch is a bit special : - It currently does not collaborate with the transaction (or any scoping) for writing (this is bad) - It can change without the lock being taken (it is protected by `wlock`) So we rely on the same mechanism as for the backup of the other dirstate file: - we only do a backup if we hold the wlock - we force a backup though the transaction Since "branch" write does not collaborate with the transaction, we cannot back it up "at the last minute" as we do for the dirstate. We have to back it up "upfront". Since we have a backup, the transaction is no longer doing its "quick_abort" and get noisy. Which is quite annoying. To work around this, and to avoid jumping in yet-another-rabbit-hole of "getting branch written properly", I am doing horrible things to the transaction in the meantime. We should be able to get this code go away during the next cycle. In the meantime, I prefer to take this small stop so that we stop abusing the "journal" and "undo" mechanism instead of the proper backup mechanism of the transaction. Also note that this change regress the warning message for the legacy fallback introduced in 2008 when issue902 got fixed in dd5a501cb97f (Mercurial 1.0). I feel like this is fine as issue 902 remains fixed, and this would only affect people deploying a mix of 15 year old Mercurial and modern mercurial, and using branch and rollback extensively.

from .i18n import _
from .pycompat import getattr
from . import (
    bookmarks as bookmarksmod,
    cmdutil,
    error,
    hg,
    lock as lockmod,
    logcmdutil,
    mergestate as mergestatemod,
    pycompat,
    registrar,
    repair,
    scmutil,
    util,
)

release = lockmod.release

cmdtable = {}
command = registrar.command(cmdtable)


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 != repo.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"debugstrip",
    [
        (
            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 debugstrip [-k] [-f] [-B bookmark] [-r] REV...'),
    helpcategory=command.CATEGORY_MAINTENANCE,
)
def debugstrip(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(logcmdutil.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 repomarks.items():
                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 != repo.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'):
            with repo.dirstate.changing_parents(repo):
                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"only(., %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 not dirstate.get_entry(f).maybe_clean
                ]
                changedfiles.extend(dirchanges)

                repo.dirstate.rebuild(urev, uctx.manifest(), changedfiles)
                repo.dirstate.write(repo.currenttransaction())

                # clear resolve state
                mergestatemod.mergestate.clean(repo)

                update = False

        strip(
            ui,
            repo,
            revs,
            backup=backup,
            update=update,
            force=opts.get(b'force'),
            bookmarks=bookmarks,
            soft=opts[b'soft'],
        )

    return 0