hgext/narrow/narrowdirstate.py

narrow: move .hg/narrowspec to .hg/store/narrowspec (BC)

The narrowspec is more closely related to the store than to the
working copy. For example, if the narrowspec changes, the set of
revlogs also needs to change (the working copy may change, but that
depends on which commit is checked out). Also, when using the share
extension, the narrowspec needs to be shared along with the
store. This patch therefore moves the narrowspec into the store/
directory.

This is clearly a breaking change, but I haven't bothered trying to
fall back to reading the narrowspec from the old location (.hg/),
because there are very few users of narrow out there. (We'll add a
temporary hack to our Google-internal extension to handle the
migration.)

Differential Revision: https://phab.mercurial-scm.org/D4099

# narrowdirstate.py - extensions to mercurial dirstate to support narrow clones
#
# Copyright 2017 Google, Inc.
#
# This software may be used and distributed according to the terms of the
# GNU General Public License version 2 or any later version.

from __future__ import absolute_import

from mercurial.i18n import _
from mercurial import (
    error,
    match as matchmod,
)

def wrapdirstate(repo, dirstate):
    """Add narrow spec dirstate ignore, block changes outside narrow spec."""

    def _editfunc(fn):
        def _wrapper(self, *args):
            dirstate = repo.dirstate
            narrowmatch = repo.narrowmatch()
            for f in args:
                if f is not None and not narrowmatch(f) and f not in dirstate:
                    raise error.Abort(_("cannot track '%s' - it is outside " +
                        "the narrow clone") % f)
            return fn(self, *args)
        return _wrapper

    class narrowdirstate(dirstate.__class__):
        def walk(self, match, subrepos, unknown, ignored, full=True,
                 narrowonly=True):
            if narrowonly:
                # hack to not exclude explicitly-specified paths so that they
                # can be warned later on e.g. dirstate.add()
                em = matchmod.exact(match._root, match._cwd, match.files())
                nm = matchmod.unionmatcher([repo.narrowmatch(), em])
                match = matchmod.intersectmatchers(match, nm)
            return super(narrowdirstate, self).walk(match, subrepos, unknown,
                                                    ignored, full)

        # Prevent adding/editing/copying/deleting files that are outside the
        # sparse checkout
        @_editfunc
        def normal(self, *args):
            return super(narrowdirstate, self).normal(*args)

        @_editfunc
        def add(self, *args):
            return super(narrowdirstate, self).add(*args)

        @_editfunc
        def normallookup(self, *args):
            return super(narrowdirstate, self).normallookup(*args)

        @_editfunc
        def copy(self, *args):
            return super(narrowdirstate, self).copy(*args)

        @_editfunc
        def remove(self, *args):
            return super(narrowdirstate, self).remove(*args)

        @_editfunc
        def merge(self, *args):
            return super(narrowdirstate, self).merge(*args)

        def rebuild(self, parent, allfiles, changedfiles=None):
            if changedfiles is None:
                # Rebuilding entire dirstate, let's filter allfiles to match the
                # narrowspec.
                allfiles = [f for f in allfiles if repo.narrowmatch()(f)]
            super(narrowdirstate, self).rebuild(parent, allfiles, changedfiles)

    dirstate.__class__ = narrowdirstate
    return dirstate