widening: trust user to give full "known" set

The new narrow_widen wire protocol command is supposed to return data
for exactly the revisions that the client requested (in order for it
to be strip-free). So we should not add ancestors the client didn't
ask for.

Differential Revision: https://phab.mercurial-scm.org/D7098

hgext/narrow/narrowbundle2.py

@@ -1,356 +1,354 b''
 # narrowbundle2.py - bundle2 extensions for narrow repository support
 #
 # 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
 import struct
 
 from mercurial.i18n import _
 from mercurial.node import nullid
 from mercurial import (
     bundle2,
     changegroup,
     error,
     exchange,
     localrepo,
     narrowspec,
     repair,
     util,
     wireprototypes,
 )
 from mercurial.interfaces import repository
 from mercurial.utils import stringutil
 
 _NARROWACL_SECTION = b'narrowacl'
 _CHANGESPECPART = b'narrow:changespec'
 _RESSPECS = b'narrow:responsespec'
 _SPECPART = b'narrow:spec'
 _SPECPART_INCLUDE = b'include'
 _SPECPART_EXCLUDE = b'exclude'
 _KILLNODESIGNAL = b'KILL'
 _DONESIGNAL = b'DONE'
 _ELIDEDCSHEADER = b'>20s20s20sl'  # cset id, p1, p2, len(text)
 _ELIDEDMFHEADER = b'>20s20s20s20sl'  # manifest id, p1, p2, link id, len(text)
 _CSHEADERSIZE = struct.calcsize(_ELIDEDCSHEADER)
 _MFHEADERSIZE = struct.calcsize(_ELIDEDMFHEADER)
 
 # Serve a changegroup for a client with a narrow clone.
 def getbundlechangegrouppart_narrow(
     bundler,
     repo,
     source,
     bundlecaps=None,
     b2caps=None,
     heads=None,
     common=None,
     **kwargs
 ):
     assert repo.ui.configbool(b'experimental', b'narrowservebrokenellipses')
 
     cgversions = b2caps.get(b'changegroup')
     cgversions = [
         v
         for v in cgversions
         if v in changegroup.supportedoutgoingversions(repo)
     ]
     if not cgversions:
         raise ValueError(_(b'no common changegroup version'))
     version = max(cgversions)
 
     include = sorted(filter(bool, kwargs.get(r'includepats', [])))
     exclude = sorted(filter(bool, kwargs.get(r'excludepats', [])))
     generateellipsesbundle2(
         bundler,
         repo,
         include,
         exclude,
         version,
         common,
         heads,
         kwargs.get(r'depth', None),
     )
 
 
 def generateellipsesbundle2(
     bundler, repo, include, exclude, version, common, heads, depth,
 ):
     match = narrowspec.match(repo.root, include=include, exclude=exclude)
     if depth is not None:
         depth = int(depth)
         if depth < 1:
             raise error.Abort(_(b'depth must be positive, got %d') % depth)
 
     heads = set(heads or repo.heads())
     common = set(common or [nullid])
 
     visitnodes, relevant_nodes, ellipsisroots = exchange._computeellipsis(
         repo, common, heads, set(), match, depth=depth
     )
 
     repo.ui.debug(b'Found %d relevant revs\n' % len(relevant_nodes))
     if visitnodes:
         packer = changegroup.getbundler(
             version,
             repo,
             matcher=match,
             ellipses=True,
             shallow=depth is not None,
             ellipsisroots=ellipsisroots,
             fullnodes=relevant_nodes,
         )
         cgdata = packer.generate(common, visitnodes, False, b'narrow_widen')
 
         part = bundler.newpart(b'changegroup', data=cgdata)
         part.addparam(b'version', version)
         if b'treemanifest' in repo.requirements:
             part.addparam(b'treemanifest', b'1')
 
 
 def generate_ellipses_bundle2_for_widening(
     bundler,
     repo,
     oldinclude,
     oldexclude,
     newinclude,
     newexclude,
     version,
     common,
     known,
 ):
     newmatch = narrowspec.match(
         repo.root, include=newinclude, exclude=newexclude
     )
 
     common = set(common or [nullid])
     # Steps:
     # 1. Send kill for "$known & ::common"
     #
     # 2. Send changegroup for ::common
     #
     # 3. Proceed.
     #
     # In the future, we can send kills for only the specific
     # nodes we know should go away or change shape, and then
     # send a data stream that tells the client something like this:
     #
     # a) apply this changegroup
     # b) apply nodes XXX, YYY, ZZZ that you already have
     # c) goto a
     #
     # until they've built up the full new state.
-    # Convert to revnums and intersect with "common". The client should
-    # have made it a subset of "common" already, but let's be safe.
-    known = set(repo.revs(b"%ln & ::%ln", known, common))
+    knownrevs = {repo.changelog.rev(n) for n in known}
     # TODO: we could send only roots() of this set, and the
     # list of nodes in common, and the client could work out
     # what to strip, instead of us explicitly sending every
     # single node.
-    deadrevs = known
+    deadrevs = knownrevs
 
     def genkills():
         for r in deadrevs:
             yield _KILLNODESIGNAL
             yield repo.changelog.node(r)
         yield _DONESIGNAL
 
     bundler.newpart(_CHANGESPECPART, data=genkills())
     newvisit, newfull, newellipsis = exchange._computeellipsis(
-        repo, set(), common, known, newmatch
+        repo, set(), common, knownrevs, newmatch
     )
     if newvisit:
         packer = changegroup.getbundler(
             version,
             repo,
             matcher=newmatch,
             ellipses=True,
             shallow=False,
             ellipsisroots=newellipsis,
             fullnodes=newfull,
         )
         cgdata = packer.generate(common, newvisit, False, b'narrow_widen')
 
         part = bundler.newpart(b'changegroup', data=cgdata)
         part.addparam(b'version', version)
         if b'treemanifest' in repo.requirements:
             part.addparam(b'treemanifest', b'1')
 
 
 @bundle2.parthandler(_SPECPART, (_SPECPART_INCLUDE, _SPECPART_EXCLUDE))
 def _handlechangespec_2(op, inpart):
     # XXX: This bundle2 handling is buggy and should be removed after hg5.2 is
     # released. New servers will send a mandatory bundle2 part named
     # 'Narrowspec' and will send specs as data instead of params.
     # Refer to issue5952 and 6019
     includepats = set(inpart.params.get(_SPECPART_INCLUDE, b'').splitlines())
     excludepats = set(inpart.params.get(_SPECPART_EXCLUDE, b'').splitlines())
     narrowspec.validatepatterns(includepats)
     narrowspec.validatepatterns(excludepats)
 
     if not repository.NARROW_REQUIREMENT in op.repo.requirements:
         op.repo.requirements.add(repository.NARROW_REQUIREMENT)
         op.repo._writerequirements()
     op.repo.setnarrowpats(includepats, excludepats)
     narrowspec.copytoworkingcopy(op.repo)
 
 
 @bundle2.parthandler(_RESSPECS)
 def _handlenarrowspecs(op, inpart):
     data = inpart.read()
     inc, exc = data.split(b'\0')
     includepats = set(inc.splitlines())
     excludepats = set(exc.splitlines())
     narrowspec.validatepatterns(includepats)
     narrowspec.validatepatterns(excludepats)
 
     if repository.NARROW_REQUIREMENT not in op.repo.requirements:
         op.repo.requirements.add(repository.NARROW_REQUIREMENT)
         op.repo._writerequirements()
     op.repo.setnarrowpats(includepats, excludepats)
     narrowspec.copytoworkingcopy(op.repo)
 
 
 @bundle2.parthandler(_CHANGESPECPART)
 def _handlechangespec(op, inpart):
     repo = op.repo
     cl = repo.changelog
 
     # changesets which need to be stripped entirely. either they're no longer
     # needed in the new narrow spec, or the server is sending a replacement
     # in the changegroup part.
     clkills = set()
 
     # A changespec part contains all the updates to ellipsis nodes
     # that will happen as a result of widening or narrowing a
     # repo. All the changes that this block encounters are ellipsis
     # nodes or flags to kill an existing ellipsis.
     chunksignal = changegroup.readexactly(inpart, 4)
     while chunksignal != _DONESIGNAL:
         if chunksignal == _KILLNODESIGNAL:
             # a node used to be an ellipsis but isn't anymore
             ck = changegroup.readexactly(inpart, 20)
             if cl.hasnode(ck):
                 clkills.add(ck)
         else:
             raise error.Abort(
                 _(b'unexpected changespec node chunk type: %s') % chunksignal
             )
         chunksignal = changegroup.readexactly(inpart, 4)
 
     if clkills:
         # preserve bookmarks that repair.strip() would otherwise strip
         op._bookmarksbackup = repo._bookmarks
 
         class dummybmstore(dict):
             def applychanges(self, repo, tr, changes):
                 pass
 
         localrepo.localrepository._bookmarks.set(repo, dummybmstore())
         chgrpfile = repair.strip(
             op.ui, repo, list(clkills), backup=True, topic=b'widen'
         )
         if chgrpfile:
             op._widen_uninterr = repo.ui.uninterruptible()
             op._widen_uninterr.__enter__()
             # presence of _widen_bundle attribute activates widen handler later
             op._widen_bundle = chgrpfile
     # Set the new narrowspec if we're widening. The setnewnarrowpats() method
     # will currently always be there when using the core+narrowhg server, but
     # other servers may include a changespec part even when not widening (e.g.
     # because we're deepening a shallow repo).
     if util.safehasattr(repo, 'setnewnarrowpats'):
         repo.setnewnarrowpats()
 
 
 def handlechangegroup_widen(op, inpart):
     """Changegroup exchange handler which restores temporarily-stripped nodes"""
     # We saved a bundle with stripped node data we must now restore.
     # This approach is based on mercurial/repair.py@6ee26a53c111.
     repo = op.repo
     ui = op.ui
 
     chgrpfile = op._widen_bundle
     del op._widen_bundle
     vfs = repo.vfs
 
     ui.note(_(b"adding branch\n"))
     f = vfs.open(chgrpfile, b"rb")
     try:
         gen = exchange.readbundle(ui, f, chgrpfile, vfs)
         # silence internal shuffling chatter
         override = {(b'ui', b'quiet'): True}
         if ui.verbose:
             override = {}
         with ui.configoverride(override):
             if isinstance(gen, bundle2.unbundle20):
                 with repo.transaction(b'strip') as tr:
                     bundle2.processbundle(repo, gen, lambda: tr)
             else:
                 gen.apply(
                     repo, b'strip', b'bundle:' + vfs.join(chgrpfile), True
                 )
     finally:
         f.close()
 
     # remove undo files
     for undovfs, undofile in repo.undofiles():
         try:
             undovfs.unlink(undofile)
         except OSError as e:
             if e.errno != errno.ENOENT:
                 ui.warn(
                     _(b'error removing %s: %s\n')
                     % (undovfs.join(undofile), stringutil.forcebytestr(e))
                 )
 
     # Remove partial backup only if there were no exceptions
     op._widen_uninterr.__exit__(None, None, None)
     vfs.unlink(chgrpfile)
 
 
 def setup():
     """Enable narrow repo support in bundle2-related extension points."""
     getbundleargs = wireprototypes.GETBUNDLE_ARGUMENTS
 
     getbundleargs[b'narrow'] = b'boolean'
     getbundleargs[b'depth'] = b'plain'
     getbundleargs[b'oldincludepats'] = b'csv'
     getbundleargs[b'oldexcludepats'] = b'csv'
     getbundleargs[b'known'] = b'csv'
 
     # Extend changegroup serving to handle requests from narrow clients.
     origcgfn = exchange.getbundle2partsmapping[b'changegroup']
 
     def wrappedcgfn(*args, **kwargs):
         repo = args[1]
         if repo.ui.has_section(_NARROWACL_SECTION):
             kwargs = exchange.applynarrowacl(repo, kwargs)
 
         if kwargs.get(r'narrow', False) and repo.ui.configbool(
             b'experimental', b'narrowservebrokenellipses'
         ):
             getbundlechangegrouppart_narrow(*args, **kwargs)
         else:
             origcgfn(*args, **kwargs)
 
     exchange.getbundle2partsmapping[b'changegroup'] = wrappedcgfn
 
     # Extend changegroup receiver so client can fixup after widen requests.
     origcghandler = bundle2.parthandlermapping[b'changegroup']
 
     def wrappedcghandler(op, inpart):
         origcghandler(op, inpart)
         if util.safehasattr(op, '_widen_bundle'):
             handlechangegroup_widen(op, inpart)
         if util.safehasattr(op, '_bookmarksbackup'):
             localrepo.localrepository._bookmarks.set(
                 op.repo, op._bookmarksbackup
             )
             del op._bookmarksbackup
 
     wrappedcghandler.params = origcghandler.params
     bundle2.parthandlermapping[b'changegroup'] = wrappedcghandler