narrow: drop support for remote expansion (BC)

Previous patches to validate narrow patterns accidentically dropped
support for the include: syntax that allows patterns to be expanded
from a remote.

This feature was never implemented in core and is only implemented on
Google's custom server. Per @martinvonz's review comment in D4522, it
is OK to drop this feature since it isn't used.

The concept of this feature does seem useful. I anticipate it making
a comeback some day in some shape or form. But for now, let's jettison
the dead code.

Differential Revision: https://phab.mercurial-scm.org/D4530

hgext/narrow/TODO.rst

@@ -1,37 +1,30 b''
 Integration with the share extension needs improvement. Right now
 we've seen some odd bugs, and the way we modify the contents of the
 .hg/shared file is unfortunate. See wrappostshare() and unsharenarrowspec().
 
 Resolve commentary on narrowrepo.wraprepo.narrowrepository.status
 about the filtering of status being done at an awkward layer. This
 came up the import to hgext, but nobody's got concrete improvement
 ideas as of then.
 
 Fold most (or preferably all) of narrowrevlog.py into core.
 
 Address commentary in narrowrevlog.excludedmanifestrevlog.add -
 specifically we should improve the collaboration with core so that
 add() never gets called on an excluded directory and we can improve
 the stand-in to raise a ProgrammingError.
 
 Figure out how to correctly produce narrowmanifestrevlog and
 narrowfilelog instances instead of monkeypatching regular revlogs at
 runtime to our subclass. Even better, merge the narrowing logic
 directly into core.
 
 Reason more completely about rename-filtering logic in
 narrowfilelog. There could be some surprises lurking there.
 
 Formally document the narrowspec format. Unify with sparse, if at all
 possible. For bonus points, unify with the server-specified narrowspec
 format.
 
 narrowrepo.setnarrowpats() or narrowspec.save() need to make sure
 they're holding the wlock.
-
-Implement a simple version of the expandnarrow wireproto command for
-core. Having configurable shorthands for narrowspecs has been useful
-at Google (and sparse has a similar feature from Facebook), so it
-probably makes sense to implement the feature in core. (Google's
-handler is entirely custom to Google, with a custom format related to
-bazel's build language, so it's not in the narrowhg distribution.)

hgext/narrow/narrowcommands.py

@@ -1,463 +1,433 b''
 # narrowcommands.py - command modifications for narrowhg extension
 #
 # 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
 
 import itertools
 import os
 
 from mercurial.i18n import _
 from mercurial import (
     cmdutil,
     commands,
     discovery,
     encoding,
     error,
     exchange,
     extensions,
     hg,
     merge,
     narrowspec,
     node,
     pycompat,
     registrar,
     repair,
     repository,
     repoview,
     sparse,
     util,
 )
 
 from . import (
     narrowwirepeer,
 )
 
 table = {}
 command = registrar.command(table)
 
 def setup():
     """Wraps user-facing mercurial commands with narrow-aware versions."""
 
     entry = extensions.wrapcommand(commands.table, 'clone', clonenarrowcmd)
     entry[1].append(('', 'narrow', None,
                      _("create a narrow clone of select files")))
     entry[1].append(('', 'depth', '',
                      _("limit the history fetched by distance from heads")))
     entry[1].append(('', 'narrowspec', '',
                      _("read narrowspecs from file")))
     # TODO(durin42): unify sparse/narrow --include/--exclude logic a bit
     if 'sparse' not in extensions.enabled():
         entry[1].append(('', 'include', [],
                          _("specifically fetch this file/directory")))
         entry[1].append(
             ('', 'exclude', [],
              _("do not fetch this file/directory, even if included")))
 
     entry = extensions.wrapcommand(commands.table, 'pull', pullnarrowcmd)
     entry[1].append(('', 'depth', '',
                      _("limit the history fetched by distance from heads")))
 
     extensions.wrapcommand(commands.table, 'archive', archivenarrowcmd)
 
-def expandpull(pullop, includepats, excludepats):
-    if not narrowspec.needsexpansion(includepats):
-        return includepats, excludepats
-
-    heads = pullop.heads or pullop.rheads
-    includepats, excludepats = pullop.remote.expandnarrow(
-        includepats, excludepats, heads)
-    pullop.repo.ui.debug('Expanded narrowspec to inc=%s, exc=%s\n' % (
-        includepats, excludepats))
-
-    includepats = set(includepats)
-    excludepats = set(excludepats)
-
-    # Nefarious remote could supply unsafe patterns. Validate them.
-    narrowspec.validatepatterns(includepats)
-    narrowspec.validatepatterns(excludepats)
-
-    return includepats, excludepats
-
 def clonenarrowcmd(orig, ui, repo, *args, **opts):
     """Wraps clone command, so 'hg clone' first wraps localrepo.clone()."""
     opts = pycompat.byteskwargs(opts)
     wrappedextraprepare = util.nullcontextmanager()
     opts_narrow = opts['narrow']
     narrowspecfile = opts['narrowspec']
 
     if narrowspecfile:
         filepath = os.path.join(pycompat.getcwd(), narrowspecfile)
         ui.status(_("reading narrowspec from '%s'\n") % filepath)
         try:
             fdata = util.readfile(filepath)
         except IOError as inst:
             raise error.Abort(_("cannot read narrowspecs from '%s': %s") %
                               (filepath, encoding.strtolocal(inst.strerror)))
 
         includes, excludes, profiles = sparse.parseconfig(ui, fdata, 'narrow')
         if profiles:
             raise error.Abort(_("cannot specify other files using '%include' in"
                                 " narrowspec"))
 
         narrowspec.validatepatterns(includes)
         narrowspec.validatepatterns(excludes)
 
         # narrowspec is passed so we should assume that user wants narrow clone
         opts_narrow = True
         opts['include'].extend(includes)
         opts['exclude'].extend(excludes)
 
     if opts_narrow:
         def pullbundle2extraprepare_widen(orig, pullop, kwargs):
             # Create narrow spec patterns from clone flags
             includepats = narrowspec.parsepatterns(opts['include'])
             excludepats = narrowspec.parsepatterns(opts['exclude'])
 
-            # If necessary, ask the server to expand the narrowspec.
-            includepats, excludepats = expandpull(
-                pullop, includepats, excludepats)
-
             if not includepats and excludepats:
                 # If nothing was included, we assume the user meant to include
                 # everything, except what they asked to exclude.
                 includepats = {'path:.'}
 
             pullop.repo.setnarrowpats(includepats, excludepats)
 
             # This will populate 'includepats' etc with the values from the
             # narrowspec we just saved.
             orig(pullop, kwargs)
 
             if opts.get('depth'):
                 kwargs['depth'] = opts['depth']
         wrappedextraprepare = extensions.wrappedfunction(exchange,
             '_pullbundle2extraprepare', pullbundle2extraprepare_widen)
 
     def pullnarrow(orig, repo, *args, **kwargs):
         if opts_narrow:
             repo.requirements.add(repository.NARROW_REQUIREMENT)
             repo._writerequirements()
 
         return orig(repo, *args, **kwargs)
 
     wrappedpull = extensions.wrappedfunction(exchange, 'pull', pullnarrow)
 
     with wrappedextraprepare, wrappedpull:
         return orig(ui, repo, *args, **pycompat.strkwargs(opts))
 
 def pullnarrowcmd(orig, ui, repo, *args, **opts):
     """Wraps pull command to allow modifying narrow spec."""
     wrappedextraprepare = util.nullcontextmanager()
     if repository.NARROW_REQUIREMENT in repo.requirements:
 
         def pullbundle2extraprepare_widen(orig, pullop, kwargs):
             orig(pullop, kwargs)
             if opts.get(r'depth'):
                 kwargs['depth'] = opts[r'depth']
         wrappedextraprepare = extensions.wrappedfunction(exchange,
             '_pullbundle2extraprepare', pullbundle2extraprepare_widen)
 
     with wrappedextraprepare:
         return orig(ui, repo, *args, **opts)
 
 def archivenarrowcmd(orig, ui, repo, *args, **opts):
     """Wraps archive command to narrow the default includes."""
     if repository.NARROW_REQUIREMENT in repo.requirements:
         repo_includes, repo_excludes = repo.narrowpats
         includes = set(opts.get(r'include', []))
         excludes = set(opts.get(r'exclude', []))
         includes, excludes, unused_invalid = narrowspec.restrictpatterns(
             includes, excludes, repo_includes, repo_excludes)
         if includes:
             opts[r'include'] = includes
         if excludes:
             opts[r'exclude'] = excludes
     return orig(ui, repo, *args, **opts)
 
 def pullbundle2extraprepare(orig, pullop, kwargs):
     repo = pullop.repo
     if repository.NARROW_REQUIREMENT not in repo.requirements:
         return orig(pullop, kwargs)
 
     if narrowwirepeer.NARROWCAP not in pullop.remote.capabilities():
         raise error.Abort(_("server doesn't support narrow clones"))
     orig(pullop, kwargs)
     kwargs['narrow'] = True
     include, exclude = repo.narrowpats
     kwargs['oldincludepats'] = include
     kwargs['oldexcludepats'] = exclude
     kwargs['includepats'] = include
     kwargs['excludepats'] = exclude
     # calculate known nodes only in ellipses cases because in non-ellipses cases
     # we have all the nodes
     if narrowwirepeer.ELLIPSESCAP in pullop.remote.capabilities():
         kwargs['known'] = [node.hex(ctx.node()) for ctx in
                            repo.set('::%ln', pullop.common)
                            if ctx.node() != node.nullid]
         if not kwargs['known']:
             # Mercurial serializes an empty list as '' and deserializes it as
             # [''], so delete it instead to avoid handling the empty string on
             # the server.
             del kwargs['known']
 
 extensions.wrapfunction(exchange,'_pullbundle2extraprepare',
                         pullbundle2extraprepare)
 
 def _narrow(ui, repo, remote, commoninc, oldincludes, oldexcludes,
             newincludes, newexcludes, force):
     oldmatch = narrowspec.match(repo.root, oldincludes, oldexcludes)
     newmatch = narrowspec.match(repo.root, newincludes, newexcludes)
 
     # This is essentially doing "hg outgoing" to find all local-only
     # commits. We will then check that the local-only commits don't
     # have any changes to files that will be untracked.
     unfi = repo.unfiltered()
     outgoing = discovery.findcommonoutgoing(unfi, remote,
                                             commoninc=commoninc)
     ui.status(_('looking for local changes to affected paths\n'))
     localnodes = []
     for n in itertools.chain(outgoing.missing, outgoing.excluded):
         if any(oldmatch(f) and not newmatch(f) for f in unfi[n].files()):
             localnodes.append(n)
     revstostrip = unfi.revs('descendants(%ln)', localnodes)
     hiddenrevs = repoview.filterrevs(repo, 'visible')
     visibletostrip = list(repo.changelog.node(r)
                           for r in (revstostrip - hiddenrevs))
     if visibletostrip:
         ui.status(_('The following changeset(s) or their ancestors have '
                     'local changes not on the remote:\n'))
         maxnodes = 10
         if ui.verbose or len(visibletostrip) <= maxnodes:
             for n in visibletostrip:
                 ui.status('%s\n' % node.short(n))
         else:
             for n in visibletostrip[:maxnodes]:
                 ui.status('%s\n' % node.short(n))
             ui.status(_('...and %d more, use --verbose to list all\n') %
                       (len(visibletostrip) - maxnodes))
         if not force:
             raise error.Abort(_('local changes found'),
                               hint=_('use --force-delete-local-changes to '
                                      'ignore'))
 
     with ui.uninterruptable():
         if revstostrip:
             tostrip = [unfi.changelog.node(r) for r in revstostrip]
             if repo['.'].node() in tostrip:
                 # stripping working copy, so move to a different commit first
                 urev = max(repo.revs('(::%n) - %ln + null',
                                      repo['.'].node(), visibletostrip))
                 hg.clean(repo, urev)
             repair.strip(ui, unfi, tostrip, topic='narrow')
 
         todelete = []
         for f, f2, size in repo.store.datafiles():
             if f.startswith('data/'):
                 file = f[5:-2]
                 if not newmatch(file):
                     todelete.append(f)
             elif f.startswith('meta/'):
                 dir = f[5:-13]
                 dirs = ['.'] + sorted(util.dirs({dir})) + [dir]
                 include = True
                 for d in dirs:
                     visit = newmatch.visitdir(d)
                     if not visit:
                         include = False
                         break
                     if visit == 'all':
                         break
                 if not include:
                     todelete.append(f)
 
         repo.destroying()
 
         with repo.transaction("narrowing"):
             for f in todelete:
                 ui.status(_('deleting %s\n') % f)
                 util.unlinkpath(repo.svfs.join(f))
                 repo.store.markremoved(f)
 
             for f in repo.dirstate:
                 if not newmatch(f):
                     repo.dirstate.drop(f)
                     repo.wvfs.unlinkpath(f)
             repo.setnarrowpats(newincludes, newexcludes)
 
         repo.destroyed()
 
 def _widen(ui, repo, remote, commoninc, newincludes, newexcludes):
     newmatch = narrowspec.match(repo.root, newincludes, newexcludes)
 
-    # TODO(martinvonz): Get expansion working with widening/narrowing.
-    if narrowspec.needsexpansion(newincludes):
-        raise error.Abort('Expansion not yet supported on pull')
-
     def pullbundle2extraprepare_widen(orig, pullop, kwargs):
         orig(pullop, kwargs)
         # The old{in,ex}cludepats have already been set by orig()
         kwargs['includepats'] = newincludes
         kwargs['excludepats'] = newexcludes
         kwargs['widen'] = True
     wrappedextraprepare = extensions.wrappedfunction(exchange,
         '_pullbundle2extraprepare', pullbundle2extraprepare_widen)
 
     # define a function that narrowbundle2 can call after creating the
     # backup bundle, but before applying the bundle from the server
     def setnewnarrowpats():
         repo.setnarrowpats(newincludes, newexcludes)
     repo.setnewnarrowpats = setnewnarrowpats
 
     with ui.uninterruptable():
         ds = repo.dirstate
         p1, p2 = ds.p1(), ds.p2()
         with ds.parentchange():
             ds.setparents(node.nullid, node.nullid)
         common = commoninc[0]
         with wrappedextraprepare:
             exchange.pull(repo, remote, heads=common)
         with ds.parentchange():
             ds.setparents(p1, p2)
 
         repo.setnewnarrowpats()
         actions = {k: [] for k in 'a am f g cd dc r dm dg m e k p pr'.split()}
         addgaction = actions['g'].append
 
         mf = repo['.'].manifest().matches(newmatch)
         for f, fn in mf.iteritems():
             if f not in repo.dirstate:
                 addgaction((f, (mf.flags(f), False),
                             "add from widened narrow clone"))
 
         merge.applyupdates(repo, actions, wctx=repo[None],
                            mctx=repo['.'], overwrite=False)
         merge.recordupdates(repo, actions, branchmerge=False)
 
 # TODO(rdamazio): Make new matcher format and update description
 @command('tracked',
     [('', 'addinclude', [], _('new paths to include')),
      ('', 'removeinclude', [], _('old paths to no longer include')),
      ('', 'addexclude', [], _('new paths to exclude')),
      ('', 'import-rules', '', _('import narrowspecs from a file')),
      ('', 'removeexclude', [], _('old paths to no longer exclude')),
      ('', 'clear', False, _('whether to replace the existing narrowspec')),
      ('', 'force-delete-local-changes', False,
        _('forces deletion of local changes when narrowing')),
     ] + commands.remoteopts,
     _('[OPTIONS]... [REMOTE]'),
     inferrepo=True)
 def trackedcmd(ui, repo, remotepath=None, *pats, **opts):
     """show or change the current narrowspec
 
     With no argument, shows the current narrowspec entries, one per line. Each
     line will be prefixed with 'I' or 'X' for included or excluded patterns,
     respectively.
 
     The narrowspec is comprised of expressions to match remote files and/or
     directories that should be pulled into your client.
     The narrowspec has *include* and *exclude* expressions, with excludes always
     trumping includes: that is, if a file matches an exclude expression, it will
     be excluded even if it also matches an include expression.
     Excluding files that were never included has no effect.
 
     Each included or excluded entry is in the format described by
     'hg help patterns'.
 
     The options allow you to add or remove included and excluded expressions.
 
     If --clear is specified, then all previous includes and excludes are DROPPED
     and replaced by the new ones specified to --addinclude and --addexclude.
     If --clear is specified without any further options, the narrowspec will be
     empty and will not match any files.
     """
     opts = pycompat.byteskwargs(opts)
     if repository.NARROW_REQUIREMENT not in repo.requirements:
         ui.warn(_('The narrow command is only supported on respositories cloned'
                   ' with --narrow.\n'))
         return 1
 
     # Before supporting, decide whether it "hg tracked --clear" should mean
     # tracking no paths or all paths.
     if opts['clear']:
         ui.warn(_('The --clear option is not yet supported.\n'))
         return 1
 
     # import rules from a file
     newrules = opts.get('import_rules')
     if newrules:
         try:
             filepath = os.path.join(pycompat.getcwd(), newrules)
             fdata = util.readfile(filepath)
         except IOError as inst:
             raise error.Abort(_("cannot read narrowspecs from '%s': %s") %
                               (filepath, encoding.strtolocal(inst.strerror)))
         includepats, excludepats, profiles = sparse.parseconfig(ui, fdata,
                                                                 'narrow')
         if profiles:
             raise error.Abort(_("including other spec files using '%include' "
                                 "is not supported in narrowspec"))
         opts['addinclude'].extend(includepats)
         opts['addexclude'].extend(excludepats)
 
-    if narrowspec.needsexpansion(opts['addinclude'] + opts['addexclude']):
-        raise error.Abort('Expansion not yet supported on widen/narrow')
-
     addedincludes = narrowspec.parsepatterns(opts['addinclude'])
     removedincludes = narrowspec.parsepatterns(opts['removeinclude'])
     addedexcludes = narrowspec.parsepatterns(opts['addexclude'])
     removedexcludes = narrowspec.parsepatterns(opts['removeexclude'])
     widening = addedincludes or removedexcludes
     narrowing = removedincludes or addedexcludes
     only_show = not widening and not narrowing
 
     # Only print the current narrowspec.
     if only_show:
         include, exclude = repo.narrowpats
 
         ui.pager('tracked')
         fm = ui.formatter('narrow', opts)
         for i in sorted(include):
             fm.startitem()
             fm.write('status', '%s ', 'I', label='narrow.included')
             fm.write('pat', '%s\n', i, label='narrow.included')
         for i in sorted(exclude):
             fm.startitem()
             fm.write('status', '%s ', 'X', label='narrow.excluded')
             fm.write('pat', '%s\n', i, label='narrow.excluded')
         fm.end()
         return 0
 
     with repo.wlock(), repo.lock():
         cmdutil.bailifchanged(repo)
 
         # Find the revisions we have in common with the remote. These will
         # be used for finding local-only changes for narrowing. They will
         # also define the set of revisions to update for widening.
         remotepath = ui.expandpath(remotepath or 'default')
         url, branches = hg.parseurl(remotepath)
         ui.status(_('comparing with %s\n') % util.hidepassword(url))
         remote = hg.peer(repo, opts, url)
         commoninc = discovery.findcommonincoming(repo, remote)
 
         oldincludes, oldexcludes = repo.narrowpats
         if narrowing:
             newincludes = oldincludes - removedincludes
             newexcludes = oldexcludes | addedexcludes
             _narrow(ui, repo, remote, commoninc, oldincludes, oldexcludes,
                     newincludes, newexcludes,
                     opts['force_delete_local_changes'])
             # _narrow() updated the narrowspec and _widen() below needs to
             # use the updated values as its base (otherwise removed includes
             # and addedexcludes will be lost in the resulting narrowspec)
             oldincludes = newincludes
             oldexcludes = newexcludes
 
         if widening:
             newincludes = oldincludes | addedincludes
             newexcludes = oldexcludes - removedexcludes
             _widen(ui, repo, remote, commoninc, newincludes, newexcludes)
 
     return 0

hgext/narrow/narrowwirepeer.py

@@ -1,66 +1,41 b''
 # narrowwirepeer.py - passes narrow spec with unbundle command
 #
 # 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,
     extensions,
     hg,
-    narrowspec,
-    node,
     wireprotov1server,
 )
 
 NARROWCAP = 'exp-narrow-1'
 ELLIPSESCAP = 'exp-ellipses-1'
 
 def uisetup():
-    def peersetup(ui, peer):
-        # We must set up the expansion before reposetup below, since it's used
-        # at clone time before we have a repo.
-        class expandingpeer(peer.__class__):
-            def expandnarrow(self, narrow_include, narrow_exclude, nodes):
-                ui.status(_("expanding narrowspec\n"))
-                if not self.capable('exp-expandnarrow'):
-                    raise error.Abort(
-                        'peer does not support expanding narrowspecs')
-
-                hex_nodes = (node.hex(n) for n in nodes)
-                new_narrowspec = self._call(
-                    'expandnarrow',
-                    includepats=','.join(narrow_include),
-                    excludepats=','.join(narrow_exclude),
-                    nodes=','.join(hex_nodes))
-
-                return narrowspec.parseserverpatterns(new_narrowspec)
-        peer.__class__ = expandingpeer
-    hg.wirepeersetupfuncs.append(peersetup)
-
     extensions.wrapfunction(wireprotov1server, '_capabilities', addnarrowcap)
 
 def addnarrowcap(orig, repo, proto):
     """add the narrow capability to the server"""
     caps = orig(repo, proto)
     caps.append(NARROWCAP)
     if repo.ui.configbool('experimental', 'narrowservebrokenellipses'):
         caps.append(ELLIPSESCAP)
     return caps
 
 def reposetup(repo):
     def wirereposetup(ui, peer):
         def wrapped(orig, cmd, *args, **kwargs):
             if cmd == 'unbundle':
                 # TODO: don't blindly add include/exclude wireproto
                 # arguments to unbundle.
                 include, exclude = repo.narrowpats
                 kwargs[r"includepats"] = ','.join(include)
                 kwargs[r"excludepats"] = ','.join(exclude)
             return orig(cmd, *args, **kwargs)
         extensions.wrapfunction(peer, '_calltwowaystream', wrapped)
     hg.wirepeersetupfuncs.append(wirereposetup)

mercurial/narrowspec.py

@@ -1,247 +1,244 b''
 # narrowspec.py - methods for working with a narrow view of a repository
 #
 # 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
 
 import errno
 
 from .i18n import _
 from . import (
     error,
     match as matchmod,
     repository,
     sparse,
     util,
 )
 
 FILENAME = 'narrowspec'
 
 # Pattern prefixes that are allowed in narrow patterns. This list MUST
 # only contain patterns that are fast and safe to evaluate. Keep in mind
 # that patterns are supplied by clients and executed on remote servers
 # as part of wire protocol commands.
 VALID_PREFIXES = (
     b'path:',
     b'rootfilesin:',
 )
 
 def parseserverpatterns(text):
     """Parses the narrowspec format that's returned by the server."""
     includepats = set()
     excludepats = set()
 
     # We get one entry per line, in the format "<key> <value>".
     # It's OK for value to contain other spaces.
     for kp in (l.split(' ', 1) for l in text.splitlines()):
         if len(kp) != 2:
             raise error.Abort(_('Invalid narrowspec pattern line: "%s"') % kp)
         key = kp[0]
         pat = kp[1]
         if key == 'include':
             includepats.add(pat)
         elif key == 'exclude':
             excludepats.add(pat)
         else:
             raise error.Abort(_('Invalid key "%s" in server response') % key)
 
     return includepats, excludepats
 
 def normalizesplitpattern(kind, pat):
     """Returns the normalized version of a pattern and kind.
 
     Returns a tuple with the normalized kind and normalized pattern.
     """
     pat = pat.rstrip('/')
     _validatepattern(pat)
     return kind, pat
 
 def _numlines(s):
     """Returns the number of lines in s, including ending empty lines."""
     # We use splitlines because it is Unicode-friendly and thus Python 3
     # compatible. However, it does not count empty lines at the end, so trick
     # it by adding a character at the end.
     return len((s + 'x').splitlines())
 
 def _validatepattern(pat):
     """Validates the pattern and aborts if it is invalid.
 
     Patterns are stored in the narrowspec as newline-separated
     POSIX-style bytestring paths. There's no escaping.
     """
 
     # We use newlines as separators in the narrowspec file, so don't allow them
     # in patterns.
     if _numlines(pat) > 1:
         raise error.Abort(_('newlines are not allowed in narrowspec paths'))
 
     components = pat.split('/')
     if '.' in components or '..' in components:
         raise error.Abort(_('"." and ".." are not allowed in narrowspec paths'))
 
 def normalizepattern(pattern, defaultkind='path'):
     """Returns the normalized version of a text-format pattern.
 
     If the pattern has no kind, the default will be added.
     """
     kind, pat = matchmod._patsplit(pattern, defaultkind)
     return '%s:%s' % normalizesplitpattern(kind, pat)
 
 def parsepatterns(pats):
     """Parses an iterable of patterns into a typed pattern set.
 
     Patterns are assumed to be ``path:`` if no prefix is present.
     For safety and performance reasons, only some prefixes are allowed.
     See ``validatepatterns()``.
 
     This function should be used on patterns that come from the user to
     normalize and validate them to the internal data structure used for
     representing patterns.
     """
     res = {normalizepattern(orig) for orig in pats}
     validatepatterns(res)
     return res
 
 def validatepatterns(pats):
     """Validate that patterns are in the expected data structure and format.
 
     And that is a set of normalized patterns beginning with ``path:`` or
     ``rootfilesin:``.
 
     This function should be used to validate internal data structures
     and patterns that are loaded from sources that use the internal,
     prefixed pattern representation (but can't necessarily be fully trusted).
     """
     if not isinstance(pats, set):
         raise error.ProgrammingError('narrow patterns should be a set; '
                                      'got %r' % pats)
 
     for pat in pats:
         if not pat.startswith(VALID_PREFIXES):
             # Use a Mercurial exception because this can happen due to user
             # bugs (e.g. manually updating spec file).
             raise error.Abort(_('invalid prefix on narrow pattern: %s') % pat,
                               hint=_('narrow patterns must begin with one of '
                                      'the following: %s') %
                                    ', '.join(VALID_PREFIXES))
 
 def format(includes, excludes):
     output = '[include]\n'
     for i in sorted(includes - excludes):
         output += i + '\n'
     output += '[exclude]\n'
     for e in sorted(excludes):
         output += e + '\n'
     return output
 
 def match(root, include=None, exclude=None):
     if not include:
         # Passing empty include and empty exclude to matchmod.match()
         # gives a matcher that matches everything, so explicitly use
         # the nevermatcher.
         return matchmod.never(root, '')
     return matchmod.match(root, '', [], include=include or [],
                           exclude=exclude or [])
 
-def needsexpansion(includes):
-    return [i for i in includes if i.startswith('include:')]
-
 def load(repo):
     try:
         spec = repo.svfs.read(FILENAME)
     except IOError as e:
         # Treat "narrowspec does not exist" the same as "narrowspec file exists
         # and is empty".
         if e.errno == errno.ENOENT:
             return set(), set()
         raise
     # maybe we should care about the profiles returned too
     includepats, excludepats, profiles = sparse.parseconfig(repo.ui, spec,
                                                             'narrow')
     if profiles:
         raise error.Abort(_("including other spec files using '%include' is not"
                             " supported in narrowspec"))
 
     validatepatterns(includepats)
     validatepatterns(excludepats)
 
     return includepats, excludepats
 
 def save(repo, includepats, excludepats):
     validatepatterns(includepats)
     validatepatterns(excludepats)
     spec = format(includepats, excludepats)
     repo.svfs.write(FILENAME, spec)
 
 def savebackup(repo, backupname):
     if repository.NARROW_REQUIREMENT not in repo.requirements:
         return
     vfs = repo.vfs
     vfs.tryunlink(backupname)
     util.copyfile(repo.svfs.join(FILENAME), vfs.join(backupname), hardlink=True)
 
 def restorebackup(repo, backupname):
     if repository.NARROW_REQUIREMENT not in repo.requirements:
         return
     util.rename(repo.vfs.join(backupname), repo.svfs.join(FILENAME))
 
 def clearbackup(repo, backupname):
     if repository.NARROW_REQUIREMENT not in repo.requirements:
         return
     repo.vfs.unlink(backupname)
 
 def restrictpatterns(req_includes, req_excludes, repo_includes, repo_excludes):
     r""" Restricts the patterns according to repo settings,
     results in a logical AND operation
 
     :param req_includes: requested includes
     :param req_excludes: requested excludes
     :param repo_includes: repo includes
     :param repo_excludes: repo excludes
     :return: include patterns, exclude patterns, and invalid include patterns.
 
     >>> restrictpatterns({'f1','f2'}, {}, ['f1'], [])
     (set(['f1']), {}, [])
     >>> restrictpatterns({'f1'}, {}, ['f1','f2'], [])
     (set(['f1']), {}, [])
     >>> restrictpatterns({'f1/fc1', 'f3/fc3'}, {}, ['f1','f2'], [])
     (set(['f1/fc1']), {}, [])
     >>> restrictpatterns({'f1_fc1'}, {}, ['f1','f2'], [])
     ([], set(['path:.']), [])
     >>> restrictpatterns({'f1/../f2/fc2'}, {}, ['f1','f2'], [])
     (set(['f2/fc2']), {}, [])
     >>> restrictpatterns({'f1/../f3/fc3'}, {}, ['f1','f2'], [])
     ([], set(['path:.']), [])
     >>> restrictpatterns({'f1/$non_exitent_var'}, {}, ['f1','f2'], [])
     (set(['f1/$non_exitent_var']), {}, [])
     """
     res_excludes = set(req_excludes)
     res_excludes.update(repo_excludes)
     invalid_includes = []
     if not req_includes:
         res_includes = set(repo_includes)
     elif 'path:.' not in repo_includes:
         res_includes = []
         for req_include in req_includes:
             req_include = util.expandpath(util.normpath(req_include))
             if req_include in repo_includes:
                 res_includes.append(req_include)
                 continue
             valid = False
             for repo_include in repo_includes:
                 if req_include.startswith(repo_include + '/'):
                     valid = True
                     res_includes.append(req_include)
                     break
             if not valid:
                 invalid_includes.append(req_include)
         if len(res_includes) == 0:
             res_excludes = {'path:.'}
         else:
             res_includes = set(res_includes)
     else:
         res_includes = set(req_includes)
     return res_includes, res_excludes, invalid_includes