annotate hgext/split.py @ 51923:b455dfddfed0

interfaces: convert the zope `Attribute` attrs to regular fields

At this point, we should have a useful protocol class.

The file syntax requires the type to be supplied for any fields that are
declared, but we'll leave the complex ones partially unspecified for now, for
simplicity.  (Also, the things documented as `Callable` are really as future
type annotating worked showed- roll with it for now, but they're marked as TODO
for fixing later.)  All of the fields and all of the attrs will need type
annotations, or the type rules say they are considered to be `Any`.  That can be
done in a separate pass, possibly applying the `dirstate.pyi` file generated
from the concrete class.

The first cut of this turned the `interfaceutil.Attribute` fields into plain
fields, and thus the types on them.  PyCharm flagged a few things as having
incompatible signatures when the concrete dirstate class subclassed this, when
the concrete class has them declared as `@property`.  So they've been changed to
`@property` here in those cases.  The remaining fields that are decorated in the
concrete class have comments noting the differences.  We'll see if they need to
be changed going forward, but leave them for now.  We'll be in trouble if the
`@util.propertycache` is needed, because we can't import that module here at
runtime, due to circular imports.

# split.py - split a changeset into smaller ones
#
# Copyright 2015 Laurent Charignon <[e-mail]>
# Copyright 2017 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.
"""command to split a changeset into smaller ones (EXPERIMENTAL)"""

from __future__ import annotations

from mercurial.i18n import _

from mercurial.node import (
    nullrev,
    short,
)

from mercurial import (
    bookmarks,
    cmdutil,
    commands,
    error,
    hg,
    logcmdutil,
    registrar,
    revsetlang,
    rewriteutil,
    scmutil,
    util,
)

# allow people to use split without explicitly enabling rebase extension
from . import rebase

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'


@command(
    b'split',
    [
        (b'r', b'rev', b'', _(b"revision to split"), _(b'REV')),
        (b'', b'rebase', True, _(b'rebase descendants after split')),
    ]
    + cmdutil.commitopts2,
    _(b'hg split [--no-rebase] [[-r] REV]'),
    helpcategory=command.CATEGORY_CHANGE_MANAGEMENT,
    helpbasic=True,
)
def split(ui, repo, *revs, **opts):
    """split a changeset into smaller ones

    Repeatedly prompt changes and commit message for new changesets until there
    is nothing left in the original changeset.

    If --rev was not given, split the working directory parent.

    By default, rebase connected non-obsoleted descendants onto the new
    changeset. Use --no-rebase to avoid the rebase.
    """
    revlist = []
    if opts.get('rev'):
        revlist.append(opts.get('rev'))
    revlist.extend(revs)
    with repo.wlock(), repo.lock():
        tr = repo.transaction(b'split')
        # If the rebase somehow runs into conflicts, make sure
        # we close the transaction so the user can continue it.
        with util.acceptintervention(tr):
            revs = logcmdutil.revrange(repo, revlist or [b'.'])
            if len(revs) > 1:
                raise error.InputError(_(b'cannot split multiple revisions'))

            rev = revs.first()
            # Handle nullrev specially here (instead of leaving for precheck()
            # below) so we get a nicer message and error code.
            if rev is None or rev == nullrev:
                ui.status(_(b'nothing to split\n'))
                return 1
            ctx = repo[rev]
            if ctx.node() is None:
                raise error.InputError(_(b'cannot split working directory'))

            if opts.get('rebase'):
                # Skip obsoleted descendants and their descendants so the rebase
                # won't cause conflicts for sure.
                descendants = list(repo.revs(b'(%d::) - (%d)', rev, rev))
                torebase = list(
                    repo.revs(
                        b'%ld - (%ld & obsolete())::', descendants, descendants
                    )
                )
            else:
                torebase = []
            rewriteutil.precheck(repo, [rev] + torebase, b'split')

            if len(ctx.parents()) > 1:
                raise error.InputError(_(b'cannot split a merge changeset'))

            cmdutil.bailifchanged(repo)

            # Deactivate bookmark temporarily so it won't get moved
            # unintentionally
            bname = repo._activebookmark
            if bname and repo._bookmarks[bname] != ctx.node():
                bookmarks.deactivate(repo)

            wnode = repo[b'.'].node()
            top = None
            try:
                top = dosplit(ui, repo, tr, ctx, **opts)
            finally:
                # top is None: split failed, need update --clean recovery.
                # wnode == ctx.node(): wnode split, no need to update.
                if top is None or wnode != ctx.node():
                    hg.clean(repo, wnode, show_stats=False)
                if bname:
                    bookmarks.activate(repo, bname)
            if torebase and top:
                dorebase(ui, repo, torebase, top)


def dosplit(ui, repo, tr, ctx, **opts):
    committed = []  # [ctx]

    # Set working parent to ctx.p1(), and keep working copy as ctx's content
    if ctx.node() != repo.dirstate.p1():
        hg.clean(repo, ctx.node(), show_stats=False)
    with repo.dirstate.changing_parents(repo):
        scmutil.movedirstate(repo, ctx.p1())

    # Any modified, added, removed, deleted result means split is incomplete
    def incomplete(repo):
        st = repo.status()
        return any((st.modified, st.added, st.removed, st.deleted))

    # Main split loop
    while incomplete(repo):
        if committed:
            header = _(
                b'HG: Splitting %s. So far it has been split into:\n'
            ) % short(ctx.node())
            # We don't want color codes in the commit message template, so
            # disable the label() template function while we render it.
            with ui.configoverride(
                {(b'templatealias', b'label(l,x)'): b"x"}, b'split'
            ):
                for c in committed:
                    summary = cmdutil.format_changeset_summary(ui, c, b'split')
                    header += _(b'HG: - %s\n') % summary
            header += _(
                b'HG: Write commit message for the next split changeset.\n'
            )
        else:
            header = _(
                b'HG: Splitting %s. Write commit message for the '
                b'first split changeset.\n'
            ) % short(ctx.node())
        opts.update(
            {
                'edit': True,
                'interactive': True,
                'message': header + ctx.description(),
            }
        )
        origctx = repo[b'.']
        commands.commit(ui, repo, **opts)
        newctx = repo[b'.']
        # Ensure user didn't do a "no-op" split (such as deselecting
        # everything).
        if origctx.node() != newctx.node():
            committed.append(newctx)

    if not committed:
        raise error.InputError(_(b'cannot split an empty revision'))

    if len(committed) != 1 or committed[0].node() != ctx.node():
        # Ensure we don't strip a node if we produce the same commit as already
        # exists
        scmutil.cleanupnodes(
            repo,
            {ctx.node(): [c.node() for c in committed]},
            operation=b'split',
            fixphase=True,
        )

    return committed[-1]


def dorebase(ui, repo, src, destctx):
    rebase.rebase(
        ui,
        repo,
        rev=[revsetlang.formatspec(b'%ld', src)],
        dest=revsetlang.formatspec(b'%d', destctx.rev()),
    )