mergestate: handle additional record types specially

This works around a bug in older Mercurial versions' handling of the v2 merge
state.

We also add a bunch of tests that make sure that
(1) we correctly abort when the merge state has an unsupported record type
(2) aborting the merge, rebase or histedit continues to work and clears out the
    merge state.

tests/fakemergerecord.py

@@ -0,0 +1,25
+# Extension to write out fake unsupported records into the merge state
+#
+#
+
+from __future__ import absolute_import
+
+from mercurial import (
+    cmdutil,
+    merge,
+)
+
+cmdtable = {}
+command = cmdutil.command(cmdtable)
+
+@command('fakemergerecord',
+         [('X', 'mandatory', None, 'add a fake mandatory record'),
+          ('x', 'advisory', None, 'add a fake advisory record')], '')
+def fakemergerecord(ui, repo, *pats, **opts):
+    ms = merge.mergestate.read(repo)
+    records = ms._makerecords()
+    if opts.get('mandatory'):
+        records.append(('X', 'mandatory record'))
+    if opts.get('advisory'):
+        records.append(('x', 'advisory record'))
+    ms._writerecords(records)

mercurial/merge.py

@@ -1,1377 +1,1394
 # merge.py - directory-level update/merge handling for Mercurial
 #
 # Copyright 2006, 2007 Matt Mackall <[e-mail]>
 #
 # 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 os
 import shutil
 import struct
 
 from .i18n import _
 from .node import (
     bin,
     hex,
     nullid,
     nullrev,
 )
 from . import (
     copies,
     destutil,
     error,
     filemerge,
     obsolete,
     subrepo,
     util,
     worker,
 )
 
 _pack = struct.pack
 _unpack = struct.unpack
 
 def _droponode(data):
     # used for compatibility for v1
     bits = data.split('\0')
     bits = bits[:-2] + bits[-1:]
     return '\0'.join(bits)
 
 class mergestate(object):
     '''track 3-way merge state of individual files
 
     The merge state is stored on disk when needed. Two files are used: one with
     an old format (version 1), and one with a new format (version 2). Version 2
     stores a superset of the data in version 1, including new kinds of records
     in the future. For more about the new format, see the documentation for
     `_readrecordsv2`.
 
     Each record can contain arbitrary content, and has an associated type. This
     `type` should be a letter. If `type` is uppercase, the record is mandatory:
     versions of Mercurial that don't support it should abort. If `type` is
     lowercase, the record can be safely ignored.
 
     Currently known records:
 
     L: the node of the "local" part of the merge (hexified version)
     O: the node of the "other" part of the merge (hexified version)
     F: a file to be merged entry
     D: a file that the external merge driver will merge internally
        (experimental)
     m: the external merge driver defined for this merge plus its run state
        (experimental)
+    X: unsupported mandatory record type (used in tests)
+    x: unsupported advisory record type (used in tests)
 
     Merge driver run states (experimental):
     u: driver-resolved files unmarked -- needs to be run next time we're about
        to resolve or commit
     m: driver-resolved files marked -- only needs to be run before commit
     s: success/skipped -- does not need to be run any more
 
     '''
     statepathv1 = 'merge/state'
     statepathv2 = 'merge/state2'
 
     @staticmethod
     def clean(repo, node=None, other=None):
         """Initialize a brand new merge state, removing any existing state on
         disk."""
         ms = mergestate(repo)
         ms.reset(node, other)
         return ms
 
     @staticmethod
     def read(repo):
         """Initialize the merge state, reading it from disk."""
         ms = mergestate(repo)
         ms._read()
         return ms
 
     def __init__(self, repo):
         """Initialize the merge state.
 
         Do not use this directly! Instead call read() or clean()."""
         self._repo = repo
         self._dirty = False
 
     def reset(self, node=None, other=None):
         self._state = {}
         self._local = None
         self._other = None
         if 'otherctx' in vars(self):
             del self.otherctx
         if node:
             self._local = node
             self._other = other
         self._readmergedriver = None
         if self.mergedriver:
             self._mdstate = 's'
         else:
             self._mdstate = 'u'
         shutil.rmtree(self._repo.join('merge'), True)
         self._dirty = False
 
     def _read(self):
         """Analyse each record content to restore a serialized state from disk
 
         This function process "record" entry produced by the de-serialization
         of on disk file.
         """
         self._state = {}
         self._local = None
         self._other = None
         if 'otherctx' in vars(self):
             del self.otherctx
         self._readmergedriver = None
         self._mdstate = 's'
         unsupported = set()
         records = self._readrecords()
         for rtype, record in records:
             if rtype == 'L':
                 self._local = bin(record)
             elif rtype == 'O':
                 self._other = bin(record)
             elif rtype == 'm':
                 bits = record.split('\0', 1)
                 mdstate = bits[1]
                 if len(mdstate) != 1 or mdstate not in 'ums':
                     # the merge driver should be idempotent, so just rerun it
                     mdstate = 'u'
 
                 self._readmergedriver = bits[0]
                 self._mdstate = mdstate
             elif rtype in 'FD':
                 bits = record.split('\0')
                 self._state[bits[0]] = bits[1:]
             elif not rtype.islower():
                 unsupported.add(rtype)
         self._dirty = False
 
         if unsupported:
             raise error.UnsupportedMergeRecords(unsupported)
 
     def _readrecords(self):
         """Read merge state from disk and return a list of record (TYPE, data)
 
         We read data from both v1 and v2 files and decide which one to use.
 
         V1 has been used by version prior to 2.9.1 and contains less data than
         v2. We read both versions and check if no data in v2 contradicts
         v1. If there is not contradiction we can safely assume that both v1
         and v2 were written at the same time and use the extract data in v2. If
         there is contradiction we ignore v2 content as we assume an old version
         of Mercurial has overwritten the mergestate file and left an old v2
         file around.
 
         returns list of record [(TYPE, data), ...]"""
         v1records = self._readrecordsv1()
         v2records = self._readrecordsv2()
         if self._v1v2match(v1records, v2records):
             return v2records
         else:
             # v1 file is newer than v2 file, use it
             # we have to infer the "other" changeset of the merge
             # we cannot do better than that with v1 of the format
             mctx = self._repo[None].parents()[-1]
             v1records.append(('O', mctx.hex()))
             # add place holder "other" file node information
             # nobody is using it yet so we do no need to fetch the data
             # if mctx was wrong `mctx[bits[-2]]` may fails.
             for idx, r in enumerate(v1records):
                 if r[0] == 'F':
                     bits = r[1].split('\0')
                     bits.insert(-2, '')
                     v1records[idx] = (r[0], '\0'.join(bits))
             return v1records
 
     def _v1v2match(self, v1records, v2records):
         oldv2 = set() # old format version of v2 record
         for rec in v2records:
             if rec[0] == 'L':
                 oldv2.add(rec)
             elif rec[0] == 'F':
                 # drop the onode data (not contained in v1)
                 oldv2.add(('F', _droponode(rec[1])))
         for rec in v1records:
             if rec not in oldv2:
                 return False
         else:
             return True
 
     def _readrecordsv1(self):
         """read on disk merge state for version 1 file
 
         returns list of record [(TYPE, data), ...]
 
         Note: the "F" data from this file are one entry short
               (no "other file node" entry)
         """
         records = []
         try:
             f = self._repo.vfs(self.statepathv1)
             for i, l in enumerate(f):
                 if i == 0:
                     records.append(('L', l[:-1]))
                 else:
                     records.append(('F', l[:-1]))
             f.close()
         except IOError as err:
             if err.errno != errno.ENOENT:
                 raise
         return records
 
     def _readrecordsv2(self):
         """read on disk merge state for version 2 file
 
         This format is a list of arbitrary records of the form:
 
           [type][length][content]
 
         `type` is a single character, `length` is a 4 byte integer, and
         `content` is an arbitrary byte sequence of length `length`.
 
+        Mercurial versions prior to 3.7 have a bug where if there are
+        unsupported mandatory merge records, attempting to clear out the merge
+        state with hg update --clean or similar aborts. The 't' record type
+        works around that by writing out what those versions treat as an
+        advisory record, but later versions interpret as special: the first
+        character is the 'real' record type and everything onwards is the data.
+
         Returns list of records [(TYPE, data), ...]."""
         records = []
         try:
             f = self._repo.vfs(self.statepathv2)
             data = f.read()
             off = 0
             end = len(data)
             while off < end:
                 rtype = data[off]
                 off += 1
                 length = _unpack('>I', data[off:(off + 4)])[0]
                 off += 4
                 record = data[off:(off + length)]
                 off += length
+                if rtype == 't':
+                    rtype, record = record[0], record[1:]
                 records.append((rtype, record))
             f.close()
         except IOError as err:
             if err.errno != errno.ENOENT:
                 raise
         return records
 
     @util.propertycache
     def mergedriver(self):
         # protect against the following:
         # - A configures a malicious merge driver in their hgrc, then
         #   pauses the merge
         # - A edits their hgrc to remove references to the merge driver
         # - A gives a copy of their entire repo, including .hg, to B
         # - B inspects .hgrc and finds it to be clean
         # - B then continues the merge and the malicious merge driver
         #  gets invoked
         configmergedriver = self._repo.ui.config('experimental', 'mergedriver')
         if (self._readmergedriver is not None
             and self._readmergedriver != configmergedriver):
             raise error.ConfigError(
                 _("merge driver changed since merge started"),
                 hint=_("revert merge driver change or abort merge"))
 
         return configmergedriver
 
     @util.propertycache
     def otherctx(self):
         return self._repo[self._other]
 
     def active(self):
         """Whether mergestate is active.
 
         Returns True if there appears to be mergestate. This is a rough proxy
         for "is a merge in progress."
         """
         # Check local variables before looking at filesystem for performance
         # reasons.
         return bool(self._local) or bool(self._state) or \
                self._repo.vfs.exists(self.statepathv1) or \
                self._repo.vfs.exists(self.statepathv2)
 
     def commit(self):
         """Write current state on disk (if necessary)"""
         if self._dirty:
             records = self._makerecords()
             self._writerecords(records)
             self._dirty = False
 
     def _makerecords(self):
         records = []
         records.append(('L', hex(self._local)))
         records.append(('O', hex(self._other)))
         if self.mergedriver:
             records.append(('m', '\0'.join([
                 self.mergedriver, self._mdstate])))
         for d, v in self._state.iteritems():
             if v[0] == 'd':
                 records.append(('D', '\0'.join([d] + v)))
             else:
                 records.append(('F', '\0'.join([d] + v)))
         return records
 
     def _writerecords(self, records):
         """Write current state on disk (both v1 and v2)"""
         self._writerecordsv1(records)
         self._writerecordsv2(records)
 
     def _writerecordsv1(self, records):
         """Write current state on disk in a version 1 file"""
         f = self._repo.vfs(self.statepathv1, 'w')
         irecords = iter(records)
         lrecords = irecords.next()
         assert lrecords[0] == 'L'
         f.write(hex(self._local) + '\n')
         for rtype, data in irecords:
             if rtype == 'F':
                 f.write('%s\n' % _droponode(data))
         f.close()
 
     def _writerecordsv2(self, records):
-        """Write current state on disk in a version 2 file"""
+        """Write current state on disk in a version 2 file
+
+        See the docstring for _readrecordsv2 for why we use 't'."""
+        # these are the records that all version 2 clients can read
+        whitelist = 'LOF'
         f = self._repo.vfs(self.statepathv2, 'w')
         for key, data in records:
             assert len(key) == 1
+            if key not in whitelist:
+                key, data = 't', '%s%s' % (key, data)
             format = '>sI%is' % len(data)
             f.write(_pack(format, key, len(data), data))
         f.close()
 
     def add(self, fcl, fco, fca, fd):
         """add a new (potentially?) conflicting file the merge state
         fcl: file context for local,
         fco: file context for remote,
         fca: file context for ancestors,
         fd:  file path of the resulting merge.
 
         note: also write the local version to the `.hg/merge` directory.
         """
         hash = util.sha1(fcl.path()).hexdigest()
         self._repo.vfs.write('merge/' + hash, fcl.data())
         self._state[fd] = ['u', hash, fcl.path(),
                            fca.path(), hex(fca.filenode()),
                            fco.path(), hex(fco.filenode()),
                            fcl.flags()]
         self._dirty = True
 
     def __contains__(self, dfile):
         return dfile in self._state
 
     def __getitem__(self, dfile):
         return self._state[dfile][0]
 
     def __iter__(self):
         return iter(sorted(self._state))
 
     def files(self):
         return self._state.keys()
 
     def mark(self, dfile, state):
         self._state[dfile][0] = state
         self._dirty = True
 
     def mdstate(self):
         return self._mdstate
 
     def unresolved(self):
         """Obtain the paths of unresolved files."""
 
         for f, entry in self._state.items():
             if entry[0] == 'u':
                 yield f
 
     def driverresolved(self):
         """Obtain the paths of driver-resolved files."""
 
         for f, entry in self._state.items():
             if entry[0] == 'd':
                 yield f
 
     def _resolve(self, preresolve, dfile, wctx, labels=None):
         """rerun merge process for file path `dfile`"""
         if self[dfile] in 'rd':
             return True, 0
         stateentry = self._state[dfile]
         state, hash, lfile, afile, anode, ofile, onode, flags = stateentry
         octx = self._repo[self._other]
         fcd = wctx[dfile]
         fco = octx[ofile]
         fca = self._repo.filectx(afile, fileid=anode)
         # "premerge" x flags
         flo = fco.flags()
         fla = fca.flags()
         if 'x' in flags + flo + fla and 'l' not in flags + flo + fla:
             if fca.node() == nullid:
                 if preresolve:
                     self._repo.ui.warn(
                         _('warning: cannot merge flags for %s\n') % afile)
             elif flags == fla:
                 flags = flo
         if preresolve:
             # restore local
             f = self._repo.vfs('merge/' + hash)
             self._repo.wwrite(dfile, f.read(), flags)
             f.close()
             complete, r = filemerge.premerge(self._repo, self._local, lfile,
                                              fcd, fco, fca, labels=labels)
         else:
             complete, r = filemerge.filemerge(self._repo, self._local, lfile,
                                               fcd, fco, fca, labels=labels)
         if r is None:
             # no real conflict
             del self._state[dfile]
             self._dirty = True
         elif not r:
             self.mark(dfile, 'r')
         return complete, r
 
     def preresolve(self, dfile, wctx, labels=None):
         """run premerge process for dfile
 
         Returns whether the merge is complete, and the exit code."""
         return self._resolve(True, dfile, wctx, labels=labels)
 
     def resolve(self, dfile, wctx, labels=None):
         """run merge process (assuming premerge was run) for dfile
 
         Returns the exit code of the merge."""
         return self._resolve(False, dfile, wctx, labels=labels)[1]
 
 def _checkunknownfile(repo, wctx, mctx, f, f2=None):
     if f2 is None:
         f2 = f
     return (os.path.isfile(repo.wjoin(f))
         and repo.wvfs.audit.check(f)
         and repo.dirstate.normalize(f) not in repo.dirstate
         and mctx[f2].cmp(wctx[f]))
 
 def _checkunknownfiles(repo, wctx, mctx, force, actions):
     """
     Considers any actions that care about the presence of conflicting unknown
     files. For some actions, the result is to abort; for others, it is to
     choose a different action.
     """
     aborts = []
     if not force:
         for f, (m, args, msg) in actions.iteritems():
             if m in ('c', 'dc'):
                 if _checkunknownfile(repo, wctx, mctx, f):
                     aborts.append(f)
             elif m == 'dg':
                 if _checkunknownfile(repo, wctx, mctx, f, args[0]):
                     aborts.append(f)
 
     for f in sorted(aborts):
         repo.ui.warn(_("%s: untracked file differs\n") % f)
     if aborts:
         raise error.Abort(_("untracked files in working directory differ "
                            "from files in requested revision"))
 
     for f, (m, args, msg) in actions.iteritems():
         if m == 'c':
             actions[f] = ('g', args, msg)
         elif m == 'cm':
             fl2, anc = args
             different = _checkunknownfile(repo, wctx, mctx, f)
             if different:
                 actions[f] = ('m', (f, f, None, False, anc),
                               "remote differs from untracked local")
             else:
                 actions[f] = ('g', (fl2,), "remote created")
 
 def _forgetremoved(wctx, mctx, branchmerge):
     """
     Forget removed files
 
     If we're jumping between revisions (as opposed to merging), and if
     neither the working directory nor the target rev has the file,
     then we need to remove it from the dirstate, to prevent the
     dirstate from listing the file when it is no longer in the
     manifest.
 
     If we're merging, and the other revision has removed a file
     that is not present in the working directory, we need to mark it
     as removed.
     """
 
     actions = {}
     m = 'f'
     if branchmerge:
         m = 'r'
     for f in wctx.deleted():
         if f not in mctx:
             actions[f] = m, None, "forget deleted"
 
     if not branchmerge:
         for f in wctx.removed():
             if f not in mctx:
                 actions[f] = 'f', None, "forget removed"
 
     return actions
 
 def _checkcollision(repo, wmf, actions):
     # build provisional merged manifest up
     pmmf = set(wmf)
 
     if actions:
         # k, dr, e and rd are no-op
         for m in 'a', 'f', 'g', 'cd', 'dc':
             for f, args, msg in actions[m]:
                 pmmf.add(f)
         for f, args, msg in actions['r']:
             pmmf.discard(f)
         for f, args, msg in actions['dm']:
             f2, flags = args
             pmmf.discard(f2)
             pmmf.add(f)
         for f, args, msg in actions['dg']:
             pmmf.add(f)
         for f, args, msg in actions['m']:
             f1, f2, fa, move, anc = args
             if move:
                 pmmf.discard(f1)
             pmmf.add(f)
 
     # check case-folding collision in provisional merged manifest
     foldmap = {}
     for f in sorted(pmmf):
         fold = util.normcase(f)
         if fold in foldmap:
             raise error.Abort(_("case-folding collision between %s and %s")
                              % (f, foldmap[fold]))
         foldmap[fold] = f
 
     # check case-folding of directories
     foldprefix = unfoldprefix = lastfull = ''
     for fold, f in sorted(foldmap.items()):
         if fold.startswith(foldprefix) and not f.startswith(unfoldprefix):
             # the folded prefix matches but actual casing is different
             raise error.Abort(_("case-folding collision between "
                                 "%s and directory of %s") % (lastfull, f))
         foldprefix = fold + '/'
         unfoldprefix = f + '/'
         lastfull = f
 
 def driverpreprocess(repo, ms, wctx, labels=None):
     """run the preprocess step of the merge driver, if any
 
     This is currently not implemented -- it's an extension point."""
     return True
 
 def driverconclude(repo, ms, wctx, labels=None):
     """run the conclude step of the merge driver, if any
 
     This is currently not implemented -- it's an extension point."""
     return True
 
 def manifestmerge(repo, wctx, p2, pa, branchmerge, force, partial,
                   acceptremote, followcopies):
     """
     Merge p1 and p2 with ancestor pa and generate merge action list
 
     branchmerge and force are as passed in to update
     partial = function to filter file lists
     acceptremote = accept the incoming changes without prompting
     """
 
     copy, movewithdir, diverge, renamedelete = {}, {}, {}, {}
 
     # manifests fetched in order are going to be faster, so prime the caches
     [x.manifest() for x in
      sorted(wctx.parents() + [p2, pa], key=lambda x: x.rev())]
 
     if followcopies:
         ret = copies.mergecopies(repo, wctx, p2, pa)
         copy, movewithdir, diverge, renamedelete = ret
 
     repo.ui.note(_("resolving manifests\n"))
     repo.ui.debug(" branchmerge: %s, force: %s, partial: %s\n"
                   % (bool(branchmerge), bool(force), bool(partial)))
     repo.ui.debug(" ancestor: %s, local: %s, remote: %s\n" % (pa, wctx, p2))
 
     m1, m2, ma = wctx.manifest(), p2.manifest(), pa.manifest()
     copied = set(copy.values())
     copied.update(movewithdir.values())
 
     if '.hgsubstate' in m1:
         # check whether sub state is modified
         for s in sorted(wctx.substate):
             if wctx.sub(s).dirty():
                 m1['.hgsubstate'] += '+'
                 break
 
     # Compare manifests
     diff = m1.diff(m2)
 
     actions = {}
     for f, ((n1, fl1), (n2, fl2)) in diff.iteritems():
         if partial and not partial(f):
             continue
         if n1 and n2: # file exists on both local and remote side
             if f not in ma:
                 fa = copy.get(f, None)
                 if fa is not None:
                     actions[f] = ('m', (f, f, fa, False, pa.node()),
                                   "both renamed from " + fa)
                 else:
                     actions[f] = ('m', (f, f, None, False, pa.node()),
                                   "both created")
             else:
                 a = ma[f]
                 fla = ma.flags(f)
                 nol = 'l' not in fl1 + fl2 + fla
                 if n2 == a and fl2 == fla:
                     actions[f] = ('k' , (), "remote unchanged")
                 elif n1 == a and fl1 == fla: # local unchanged - use remote
                     if n1 == n2: # optimization: keep local content
                         actions[f] = ('e', (fl2,), "update permissions")
                     else:
                         actions[f] = ('g', (fl2,), "remote is newer")
                 elif nol and n2 == a: # remote only changed 'x'
                     actions[f] = ('e', (fl2,), "update permissions")
                 elif nol and n1 == a: # local only changed 'x'
                     actions[f] = ('g', (fl1,), "remote is newer")
                 else: # both changed something
                     actions[f] = ('m', (f, f, f, False, pa.node()),
                                    "versions differ")
         elif n1: # file exists only on local side
             if f in copied:
                 pass # we'll deal with it on m2 side
             elif f in movewithdir: # directory rename, move local
                 f2 = movewithdir[f]
                 if f2 in m2:
                     actions[f2] = ('m', (f, f2, None, True, pa.node()),
                                    "remote directory rename, both created")
                 else:
                     actions[f2] = ('dm', (f, fl1),
                                    "remote directory rename - move from " + f)
             elif f in copy:
                 f2 = copy[f]
                 actions[f] = ('m', (f, f2, f2, False, pa.node()),
                               "local copied/moved from " + f2)
             elif f in ma: # clean, a different, no remote
                 if n1 != ma[f]:
                     if acceptremote:
                         actions[f] = ('r', None, "remote delete")
                     else:
                         actions[f] = ('cd', (f, None, f, False, pa.node()),
                                       "prompt changed/deleted")
                 elif n1[20:] == 'a':
                     # This extra 'a' is added by working copy manifest to mark
                     # the file as locally added. We should forget it instead of
                     # deleting it.
                     actions[f] = ('f', None, "remote deleted")
                 else:
                     actions[f] = ('r', None, "other deleted")
         elif n2: # file exists only on remote side
             if f in copied:
                 pass # we'll deal with it on m1 side
             elif f in movewithdir:
                 f2 = movewithdir[f]
                 if f2 in m1:
                     actions[f2] = ('m', (f2, f, None, False, pa.node()),
                                    "local directory rename, both created")
                 else:
                     actions[f2] = ('dg', (f, fl2),
                                    "local directory rename - get from " + f)
             elif f in copy:
                 f2 = copy[f]
                 if f2 in m2:
                     actions[f] = ('m', (f2, f, f2, False, pa.node()),
                                   "remote copied from " + f2)
                 else:
                     actions[f] = ('m', (f2, f, f2, True, pa.node()),
                                   "remote moved from " + f2)
             elif f not in ma:
                 # local unknown, remote created: the logic is described by the
                 # following table:
                 #
                 # force  branchmerge  different  |  action
                 #   n         *           *      |   create
                 #   y         n           *      |   create
                 #   y         y           n      |   create
                 #   y         y           y      |   merge
                 #
                 # Checking whether the files are different is expensive, so we
                 # don't do that when we can avoid it.
                 if not force:
                     actions[f] = ('c', (fl2,), "remote created")
                 elif not branchmerge:
                     actions[f] = ('c', (fl2,), "remote created")
                 else:
                     actions[f] = ('cm', (fl2, pa.node()),
                                   "remote created, get or merge")
             elif n2 != ma[f]:
                 if acceptremote:
                     actions[f] = ('c', (fl2,), "remote recreating")
                 else:
                     actions[f] = ('dc', (None, f, f, False, pa.node()),
                                   "prompt deleted/changed")
 
     return actions, diverge, renamedelete
 
 def _resolvetrivial(repo, wctx, mctx, ancestor, actions):
     """Resolves false conflicts where the nodeid changed but the content
        remained the same."""
 
     for f, (m, args, msg) in actions.items():
         if m == 'cd' and f in ancestor and not wctx[f].cmp(ancestor[f]):
             # local did change but ended up with same content
             actions[f] = 'r', None, "prompt same"
         elif m == 'dc' and f in ancestor and not mctx[f].cmp(ancestor[f]):
             # remote did change but ended up with same content
             del actions[f] # don't get = keep local deleted
 
 def calculateupdates(repo, wctx, mctx, ancestors, branchmerge, force, partial,
                      acceptremote, followcopies):
     "Calculate the actions needed to merge mctx into wctx using ancestors"
 
     if len(ancestors) == 1: # default
         actions, diverge, renamedelete = manifestmerge(
             repo, wctx, mctx, ancestors[0], branchmerge, force, partial,
             acceptremote, followcopies)
         _checkunknownfiles(repo, wctx, mctx, force, actions)
 
     else: # only when merge.preferancestor=* - the default
         repo.ui.note(
             _("note: merging %s and %s using bids from ancestors %s\n") %
             (wctx, mctx, _(' and ').join(str(anc) for anc in ancestors)))
 
         # Call for bids
         fbids = {} # mapping filename to bids (action method to list af actions)
         diverge, renamedelete = None, None
         for ancestor in ancestors:
             repo.ui.note(_('\ncalculating bids for ancestor %s\n') % ancestor)
             actions, diverge1, renamedelete1 = manifestmerge(
                 repo, wctx, mctx, ancestor, branchmerge, force, partial,
                 acceptremote, followcopies)
             _checkunknownfiles(repo, wctx, mctx, force, actions)
 
             # Track the shortest set of warning on the theory that bid
             # merge will correctly incorporate more information
             if diverge is None or len(diverge1) < len(diverge):
                 diverge = diverge1
             if renamedelete is None or len(renamedelete) < len(renamedelete1):
                 renamedelete = renamedelete1
 
             for f, a in sorted(actions.iteritems()):
                 m, args, msg = a
                 repo.ui.debug(' %s: %s -> %s\n' % (f, msg, m))
                 if f in fbids:
                     d = fbids[f]
                     if m in d:
                         d[m].append(a)
                     else:
                         d[m] = [a]
                 else:
                     fbids[f] = {m: [a]}
 
         # Pick the best bid for each file
         repo.ui.note(_('\nauction for merging merge bids\n'))
         actions = {}
         for f, bids in sorted(fbids.items()):
             # bids is a mapping from action method to list af actions
             # Consensus?
             if len(bids) == 1: # all bids are the same kind of method
                 m, l = bids.items()[0]
                 if all(a == l[0] for a in l[1:]): # len(bids) is > 1
                     repo.ui.note(" %s: consensus for %s\n" % (f, m))
                     actions[f] = l[0]
                     continue
             # If keep is an option, just do it.
             if 'k' in bids:
                 repo.ui.note(" %s: picking 'keep' action\n" % f)
                 actions[f] = bids['k'][0]
                 continue
             # If there are gets and they all agree [how could they not?], do it.
             if 'g' in bids:
                 ga0 = bids['g'][0]
                 if all(a == ga0 for a in bids['g'][1:]):
                     repo.ui.note(" %s: picking 'get' action\n" % f)
                     actions[f] = ga0
                     continue
             # TODO: Consider other simple actions such as mode changes
             # Handle inefficient democrazy.
             repo.ui.note(_(' %s: multiple bids for merge action:\n') % f)
             for m, l in sorted(bids.items()):
                 for _f, args, msg in l:
                     repo.ui.note('  %s -> %s\n' % (msg, m))
             # Pick random action. TODO: Instead, prompt user when resolving
             m, l = bids.items()[0]
             repo.ui.warn(_(' %s: ambiguous merge - picked %s action\n') %
                          (f, m))
             actions[f] = l[0]
             continue
         repo.ui.note(_('end of auction\n\n'))
 
     _resolvetrivial(repo, wctx, mctx, ancestors[0], actions)
 
     if wctx.rev() is None:
         fractions = _forgetremoved(wctx, mctx, branchmerge)
         actions.update(fractions)
 
     return actions, diverge, renamedelete
 
 def batchremove(repo, actions):
     """apply removes to the working directory
 
     yields tuples for progress updates
     """
     verbose = repo.ui.verbose
     unlink = util.unlinkpath
     wjoin = repo.wjoin
     audit = repo.wvfs.audit
     i = 0
     for f, args, msg in actions:
         repo.ui.debug(" %s: %s -> r\n" % (f, msg))
         if verbose:
             repo.ui.note(_("removing %s\n") % f)
         audit(f)
         try:
             unlink(wjoin(f), ignoremissing=True)
         except OSError as inst:
             repo.ui.warn(_("update failed to remove %s: %s!\n") %
                          (f, inst.strerror))
         if i == 100:
             yield i, f
             i = 0
         i += 1
     if i > 0:
         yield i, f
 
 def batchget(repo, mctx, actions):
     """apply gets to the working directory
 
     mctx is the context to get from
 
     yields tuples for progress updates
     """
     verbose = repo.ui.verbose
     fctx = mctx.filectx
     wwrite = repo.wwrite
     i = 0
     for f, args, msg in actions:
         repo.ui.debug(" %s: %s -> g\n" % (f, msg))
         if verbose:
             repo.ui.note(_("getting %s\n") % f)
         wwrite(f, fctx(f).data(), args[0])
         if i == 100:
             yield i, f
             i = 0
         i += 1
     if i > 0:
         yield i, f
 
 def applyupdates(repo, actions, wctx, mctx, overwrite, labels=None):
     """apply the merge action list to the working directory
 
     wctx is the working copy context
     mctx is the context to be merged into the working copy
 
     Return a tuple of counts (updated, merged, removed, unresolved) that
     describes how many files were affected by the update.
     """
 
     updated, merged, removed, unresolved = 0, 0, 0, 0
     ms = mergestate.clean(repo, wctx.p1().node(), mctx.node())
     moves = []
     for m, l in actions.items():
         l.sort()
 
     # prescan for merges
     for f, args, msg in actions['m']:
         f1, f2, fa, move, anc = args
         if f == '.hgsubstate': # merged internally
             continue
         repo.ui.debug(" preserving %s for resolve of %s\n" % (f1, f))
         fcl = wctx[f1]
         fco = mctx[f2]
         actx = repo[anc]
         if fa in actx:
             fca = actx[fa]
         else:
             fca = repo.filectx(f1, fileid=nullrev)
         ms.add(fcl, fco, fca, f)
         if f1 != f and move:
             moves.append(f1)
 
     audit = repo.wvfs.audit
     _updating = _('updating')
     _files = _('files')
     progress = repo.ui.progress
 
     # remove renamed files after safely stored
     for f in moves:
         if os.path.lexists(repo.wjoin(f)):
             repo.ui.debug("removing %s\n" % f)
             audit(f)
             util.unlinkpath(repo.wjoin(f))
 
     numupdates = sum(len(l) for m, l in actions.items() if m != 'k')
 
     if [a for a in actions['r'] if a[0] == '.hgsubstate']:
         subrepo.submerge(repo, wctx, mctx, wctx, overwrite)
 
     # remove in parallel (must come first)
     z = 0
     prog = worker.worker(repo.ui, 0.001, batchremove, (repo,), actions['r'])
     for i, item in prog:
         z += i
         progress(_updating, z, item=item, total=numupdates, unit=_files)
     removed = len(actions['r'])
 
     # get in parallel
     prog = worker.worker(repo.ui, 0.001, batchget, (repo, mctx), actions['g'])
     for i, item in prog:
         z += i
         progress(_updating, z, item=item, total=numupdates, unit=_files)
     updated = len(actions['g'])
 
     if [a for a in actions['g'] if a[0] == '.hgsubstate']:
         subrepo.submerge(repo, wctx, mctx, wctx, overwrite)
 
     # forget (manifest only, just log it) (must come first)
     for f, args, msg in actions['f']:
         repo.ui.debug(" %s: %s -> f\n" % (f, msg))
         z += 1
         progress(_updating, z, item=f, total=numupdates, unit=_files)
 
     # re-add (manifest only, just log it)
     for f, args, msg in actions['a']:
         repo.ui.debug(" %s: %s -> a\n" % (f, msg))
         z += 1
         progress(_updating, z, item=f, total=numupdates, unit=_files)
 
     # keep (noop, just log it)
     for f, args, msg in actions['k']:
         repo.ui.debug(" %s: %s -> k\n" % (f, msg))
         # no progress
 
     # directory rename, move local
     for f, args, msg in actions['dm']:
         repo.ui.debug(" %s: %s -> dm\n" % (f, msg))
         z += 1
         progress(_updating, z, item=f, total=numupdates, unit=_files)
         f0, flags = args
         repo.ui.note(_("moving %s to %s\n") % (f0, f))
         audit(f)
         repo.wwrite(f, wctx.filectx(f0).data(), flags)
         util.unlinkpath(repo.wjoin(f0))
         updated += 1
 
     # local directory rename, get
     for f, args, msg in actions['dg']:
         repo.ui.debug(" %s: %s -> dg\n" % (f, msg))
         z += 1
         progress(_updating, z, item=f, total=numupdates, unit=_files)
         f0, flags = args
         repo.ui.note(_("getting %s to %s\n") % (f0, f))
         repo.wwrite(f, mctx.filectx(f0).data(), flags)
         updated += 1
 
     # exec
     for f, args, msg in actions['e']:
         repo.ui.debug(" %s: %s -> e\n" % (f, msg))
         z += 1
         progress(_updating, z, item=f, total=numupdates, unit=_files)
         flags, = args
         audit(f)
         util.setflags(repo.wjoin(f), 'l' in flags, 'x' in flags)
         updated += 1
 
     mergeactions = actions['m']
     # the ordering is important here -- ms.mergedriver will raise if the merge
     # driver has changed, and we want to be able to bypass it when overwrite is
     # True
     usemergedriver = not overwrite and mergeactions and ms.mergedriver
 
     if usemergedriver:
         ms.commit()
         proceed = driverpreprocess(repo, ms, wctx, labels=labels)
         # the driver might leave some files unresolved
         unresolvedf = set(ms.unresolved())
         if not proceed:
             # XXX setting unresolved to at least 1 is a hack to make sure we
             # error out
             return updated, merged, removed, max(len(unresolvedf), 1)
         newactions = []
         for f, args, msg in mergeactions:
             if f in unresolvedf:
                 newactions.append((f, args, msg))
         mergeactions = newactions
 
     # premerge
     tocomplete = []
     for f, args, msg in mergeactions:
         repo.ui.debug(" %s: %s -> m (premerge)\n" % (f, msg))
         z += 1
         progress(_updating, z, item=f, total=numupdates, unit=_files)
         if f == '.hgsubstate': # subrepo states need updating
             subrepo.submerge(repo, wctx, mctx, wctx.ancestor(mctx),
                              overwrite)
             continue
         audit(f)
         complete, r = ms.preresolve(f, wctx, labels=labels)
         if complete:
             if r is not None and r > 0:
                 unresolved += 1
             else:
                 if r is None:
                     updated += 1
                 else:
                     merged += 1
         else:
             numupdates += 1
             tocomplete.append((f, args, msg))
 
     # merge
     for f, args, msg in tocomplete:
         repo.ui.debug(" %s: %s -> m (merge)\n" % (f, msg))
         z += 1
         progress(_updating, z, item=f, total=numupdates, unit=_files)
         r = ms.resolve(f, wctx, labels=labels)
         if r is not None and r > 0:
             unresolved += 1
         else:
             if r is None:
                 updated += 1
             else:
                 merged += 1
 
     ms.commit()
 
     if usemergedriver and not unresolved and ms.mdstate() != 's':
         if not driverconclude(repo, ms, wctx, labels=labels):
             # XXX setting unresolved to at least 1 is a hack to make sure we
             # error out
             unresolved = max(unresolved, 1)
 
         ms.commit()
 
     progress(_updating, None, total=numupdates, unit=_files)
 
     return updated, merged, removed, unresolved
 
 def recordupdates(repo, actions, branchmerge):
     "record merge actions to the dirstate"
     # remove (must come first)
     for f, args, msg in actions['r']:
         if branchmerge:
             repo.dirstate.remove(f)
         else:
             repo.dirstate.drop(f)
 
     # forget (must come first)
     for f, args, msg in actions['f']:
         repo.dirstate.drop(f)
 
     # re-add
     for f, args, msg in actions['a']:
         if not branchmerge:
             repo.dirstate.add(f)
 
     # exec change
     for f, args, msg in actions['e']:
         repo.dirstate.normallookup(f)
 
     # keep
     for f, args, msg in actions['k']:
         pass
 
     # get
     for f, args, msg in actions['g']:
         if branchmerge:
             repo.dirstate.otherparent(f)
         else:
             repo.dirstate.normal(f)
 
     # merge
     for f, args, msg in actions['m']:
         f1, f2, fa, move, anc = args
         if branchmerge:
             # We've done a branch merge, mark this file as merged
             # so that we properly record the merger later
             repo.dirstate.merge(f)
             if f1 != f2: # copy/rename
                 if move:
                     repo.dirstate.remove(f1)
                 if f1 != f:
                     repo.dirstate.copy(f1, f)
                 else:
                     repo.dirstate.copy(f2, f)
         else:
             # We've update-merged a locally modified file, so
             # we set the dirstate to emulate a normal checkout
             # of that file some time in the past. Thus our
             # merge will appear as a normal local file
             # modification.
             if f2 == f: # file not locally copied/moved
                 repo.dirstate.normallookup(f)
             if move:
                 repo.dirstate.drop(f1)
 
     # directory rename, move local
     for f, args, msg in actions['dm']:
         f0, flag = args
         if branchmerge:
             repo.dirstate.add(f)
             repo.dirstate.remove(f0)
             repo.dirstate.copy(f0, f)
         else:
             repo.dirstate.normal(f)
             repo.dirstate.drop(f0)
 
     # directory rename, get
     for f, args, msg in actions['dg']:
         f0, flag = args
         if branchmerge:
             repo.dirstate.add(f)
             repo.dirstate.copy(f0, f)
         else:
             repo.dirstate.normal(f)
 
 def update(repo, node, branchmerge, force, partial, ancestor=None,
            mergeancestor=False, labels=None):
     """
     Perform a merge between the working directory and the given node
 
     node = the node to update to, or None if unspecified
     branchmerge = whether to merge between branches
     force = whether to force branch merging or file overwriting
     partial = a function to filter file lists (dirstate not updated)
     mergeancestor = whether it is merging with an ancestor. If true,
       we should accept the incoming changes for any prompts that occur.
       If false, merging with an ancestor (fast-forward) is only allowed
       between different named branches. This flag is used by rebase extension
       as a temporary fix and should be avoided in general.
 
     The table below shows all the behaviors of the update command
     given the -c and -C or no options, whether the working directory
     is dirty, whether a revision is specified, and the relationship of
     the parent rev to the target rev (linear, on the same named
     branch, or on another named branch).
 
     This logic is tested by test-update-branches.t.
 
     -c  -C  dirty  rev  |  linear      same    cross
      n   n    n     n   |    ok        (1)       x
      n   n    n     y   |    ok        ok       ok
      n   n    y     n   |   merge      (2)      (2)
      n   n    y     y   |   merge      (3)      (3)
      n   y    *     *   |   discard   discard   discard
      y   n    y     *   |    (4)       (4)      (4)
      y   n    n     *   |    ok        ok       ok
      y   y    *     *   |    (5)       (5)      (5)
 
     x = can't happen
     * = don't-care
     1 = abort: not a linear update (merge or update --check to force update)
     2 = abort: uncommitted changes (commit and merge, or update --clean to
                  discard changes)
     3 = abort: uncommitted changes (commit or update --clean to discard changes)
     4 = abort: uncommitted changes (checked in commands.py)
     5 = incompatible options (checked in commands.py)
 
     Return the same tuple as applyupdates().
     """
 
     onode = node
     wlock = repo.wlock()
     try:
         wc = repo[None]
         pl = wc.parents()
         p1 = pl[0]
         pas = [None]
         if ancestor is not None:
             pas = [repo[ancestor]]
 
         if node is None:
             if (repo.ui.configbool('devel', 'all-warnings')
                     or repo.ui.configbool('devel', 'oldapi')):
                 repo.ui.develwarn('update with no target')
             rev, _mark, _act = destutil.destupdate(repo)
             node = repo[rev].node()
 
         overwrite = force and not branchmerge
 
         p2 = repo[node]
         if pas[0] is None:
             if repo.ui.configlist('merge', 'preferancestor', ['*']) == ['*']:
                 cahs = repo.changelog.commonancestorsheads(p1.node(), p2.node())
                 pas = [repo[anc] for anc in (sorted(cahs) or [nullid])]
             else:
                 pas = [p1.ancestor(p2, warn=branchmerge)]
 
         fp1, fp2, xp1, xp2 = p1.node(), p2.node(), str(p1), str(p2)
 
         ### check phase
         if not overwrite and len(pl) > 1:
             raise error.Abort(_("outstanding uncommitted merge"))
         if branchmerge:
             if pas == [p2]:
                 raise error.Abort(_("merging with a working directory ancestor"
                                    " has no effect"))
             elif pas == [p1]:
                 if not mergeancestor and p1.branch() == p2.branch():
                     raise error.Abort(_("nothing to merge"),
                                      hint=_("use 'hg update' "
                                             "or check 'hg heads'"))
             if not force and (wc.files() or wc.deleted()):
                 raise error.Abort(_("uncommitted changes"),
                                  hint=_("use 'hg status' to list changes"))
             for s in sorted(wc.substate):
                 wc.sub(s).bailifchanged()
 
         elif not overwrite:
             if p1 == p2: # no-op update
                 # call the hooks and exit early
                 repo.hook('preupdate', throw=True, parent1=xp2, parent2='')
                 repo.hook('update', parent1=xp2, parent2='', error=0)
                 return 0, 0, 0, 0
 
             if pas not in ([p1], [p2]):  # nonlinear
                 dirty = wc.dirty(missing=True)
                 if dirty or onode is None:
                     # Branching is a bit strange to ensure we do the minimal
                     # amount of call to obsolete.background.
                     foreground = obsolete.foreground(repo, [p1.node()])
                     # note: the <node> variable contains a random identifier
                     if repo[node].node() in foreground:
                         pas = [p1]  # allow updating to successors
                     elif dirty:
                         msg = _("uncommitted changes")
                         if onode is None:
                             hint = _("commit and merge, or update --clean to"
                                      " discard changes")
                         else:
                             hint = _("commit or update --clean to discard"
                                      " changes")
                         raise error.Abort(msg, hint=hint)
                     else:  # node is none
                         msg = _("not a linear update")
                         hint = _("merge or update --check to force update")
                         raise error.Abort(msg, hint=hint)
                 else:
                     # Allow jumping branches if clean and specific rev given
                     pas = [p1]
 
         # deprecated config: merge.followcopies
         followcopies = False
         if overwrite:
             pas = [wc]
         elif pas == [p2]: # backwards
             pas = [wc.p1()]
         elif not branchmerge and not wc.dirty(missing=True):
             pass
         elif pas[0] and repo.ui.configbool('merge', 'followcopies', True):
             followcopies = True
 
         ### calculate phase
         actionbyfile, diverge, renamedelete = calculateupdates(
             repo, wc, p2, pas, branchmerge, force, partial, mergeancestor,
             followcopies)
         # Convert to dictionary-of-lists format
         actions = dict((m, []) for m in 'a f g cd dc r dm dg m e k'.split())
         for f, (m, args, msg) in actionbyfile.iteritems():
             if m not in actions:
                 actions[m] = []
             actions[m].append((f, args, msg))
 
         if not util.checkcase(repo.path):
             # check collision between files only in p2 for clean update
             if (not branchmerge and
                 (force or not wc.dirty(missing=True, branch=False))):
                 _checkcollision(repo, p2.manifest(), None)
             else:
                 _checkcollision(repo, wc.manifest(), actions)
 
         # Prompt and create actions. TODO: Move this towards resolve phase.
         for f, args, msg in sorted(actions['cd']):
             if repo.ui.promptchoice(
                 _("local changed %s which remote deleted\n"
                   "use (c)hanged version or (d)elete?"
                   "$$ &Changed $$ &Delete") % f, 0):
                 actions['r'].append((f, None, "prompt delete"))
             else:
                 actions['a'].append((f, None, "prompt keep"))
 
         for f, args, msg in sorted(actions['dc']):
             f1, f2, fa, move, anc = args
             flags = p2[f2].flags()
             if repo.ui.promptchoice(
                 _("remote changed %s which local deleted\n"
                   "use (c)hanged version or leave (d)eleted?"
                   "$$ &Changed $$ &Deleted") % f, 0) == 0:
                 actions['g'].append((f, (flags,), "prompt recreating"))
 
         # divergent renames
         for f, fl in sorted(diverge.iteritems()):
             repo.ui.warn(_("note: possible conflict - %s was renamed "
                            "multiple times to:\n") % f)
             for nf in fl:
                 repo.ui.warn(" %s\n" % nf)
 
         # rename and delete
         for f, fl in sorted(renamedelete.iteritems()):
             repo.ui.warn(_("note: possible conflict - %s was deleted "
                            "and renamed to:\n") % f)
             for nf in fl:
                 repo.ui.warn(" %s\n" % nf)
 
         ### apply phase
         if not branchmerge: # just jump to the new rev
             fp1, fp2, xp1, xp2 = fp2, nullid, xp2, ''
         if not partial:
             repo.hook('preupdate', throw=True, parent1=xp1, parent2=xp2)
             # note that we're in the middle of an update
             repo.vfs.write('updatestate', p2.hex())
 
         stats = applyupdates(repo, actions, wc, p2, overwrite, labels=labels)
 
         if not partial:
             repo.dirstate.beginparentchange()
             repo.setparents(fp1, fp2)
             recordupdates(repo, actions, branchmerge)
             # update completed, clear state
             util.unlink(repo.join('updatestate'))
 
             if not branchmerge:
                 repo.dirstate.setbranch(p2.branch())
             repo.dirstate.endparentchange()
     finally:
         wlock.release()
 
     if not partial:
         repo.hook('update', parent1=xp1, parent2=xp2, error=stats[3])
     return stats
 
 def graft(repo, ctx, pctx, labels):
     """Do a graft-like merge.
 
     This is a merge where the merge ancestor is chosen such that one
     or more changesets are grafted onto the current changeset. In
     addition to the merge, this fixes up the dirstate to include only
     a single parent and tries to duplicate any renames/copies
     appropriately.
 
     ctx - changeset to rebase
     pctx - merge base, usually ctx.p1()
     labels - merge labels eg ['local', 'graft']
 
     """
     # If we're grafting a descendant onto an ancestor, be sure to pass
     # mergeancestor=True to update. This does two things: 1) allows the merge if
     # the destination is the same as the parent of the ctx (so we can use graft
     # to copy commits), and 2) informs update that the incoming changes are
     # newer than the destination so it doesn't prompt about "remote changed foo
     # which local deleted".
     mergeancestor = repo.changelog.isancestor(repo['.'].node(), ctx.node())
 
     stats = update(repo, ctx.node(), True, True, False, pctx.node(),
                    mergeancestor=mergeancestor, labels=labels)
 
     # drop the second merge parent
     repo.dirstate.beginparentchange()
     repo.setparents(repo['.'].node(), nullid)
     repo.dirstate.write(repo.currenttransaction())
     # fix up dirstate for copies and renames
     copies.duplicatecopies(repo, ctx.rev(), pctx.rev())
     repo.dirstate.endparentchange()
     return stats

tests/test-histedit-non-commute-abort.t

@@ -1,123 +1,158
   $ . "$TESTDIR/histedit-helpers.sh"
 
   $ cat >> $HGRCPATH <<EOF
   > [extensions]
   > histedit=
   > EOF
 
   $ initrepo ()
   > {
   >     hg init r
   >     cd r
   >     for x in a b c d e f ; do
   >         echo $x > $x
   >         hg add $x
   >         hg ci -m $x
   >     done
   >     echo a >> e
   >     hg ci -m 'does not commute with e'
   >     cd ..
   > }
 
   $ initrepo
   $ cd r
 
 log before edit
   $ hg log --graph
   @  changeset:   6:bfa474341cc9
   |  tag:         tip
   |  user:        test
   |  date:        Thu Jan 01 00:00:00 1970 +0000
   |  summary:     does not commute with e
   |
   o  changeset:   5:652413bf663e
   |  user:        test
   |  date:        Thu Jan 01 00:00:00 1970 +0000
   |  summary:     f
   |
   o  changeset:   4:e860deea161a
   |  user:        test
   |  date:        Thu Jan 01 00:00:00 1970 +0000
   |  summary:     e
   |
   o  changeset:   3:055a42cdd887
   |  user:        test
   |  date:        Thu Jan 01 00:00:00 1970 +0000
   |  summary:     d
   |
   o  changeset:   2:177f92b77385
   |  user:        test
   |  date:        Thu Jan 01 00:00:00 1970 +0000
   |  summary:     c
   |
   o  changeset:   1:d2ae7f538514
   |  user:        test
   |  date:        Thu Jan 01 00:00:00 1970 +0000
   |  summary:     b
   |
   o  changeset:   0:cb9a9f314b8b
      user:        test
      date:        Thu Jan 01 00:00:00 1970 +0000
      summary:     a
   
 
 edit the history
   $ hg histedit 177f92b77385 --commands - 2>&1 <<EOF | fixbundle
   > pick 177f92b77385 c
   > pick 055a42cdd887 d
   > pick bfa474341cc9 does not commute with e
   > pick e860deea161a e
   > pick 652413bf663e f
   > EOF
   0 files updated, 0 files merged, 2 files removed, 0 files unresolved
   0 files updated, 0 files merged, 0 files removed, 0 files unresolved
   merging e
   warning: conflicts while merging e! (edit, then use 'hg resolve --mark')
   Fix up the change and run hg histedit --continue
 
+insert unsupported advisory merge record
+  $ hg --config extensions.fakemergerecord=$TESTDIR/fakemergerecord.py fakemergerecord -x
+  $ hg debugmergestate
+  * version 2 records
+  local: 8f7551c7e4a2f2efe0bc8c741baf7f227d65d758
+  other: e860deea161a2f77de56603b340ebbb4536308ae
+  unrecognized entry: x	advisory record
+  file: e (record type "F", state "u", hash 58e6b3a414a1e090dfc6029add0f3555ccba127f)
+    local path: e (flags "")
+    ancestor path: e (node 0000000000000000000000000000000000000000)
+    other path: e (node 6b67ccefd5ce6de77e7ead4f5292843a0255329f)
+  $ hg resolve -l
+  U e
 
-abort the edit
+insert unsupported mandatory merge record
+  $ hg --config extensions.fakemergerecord=$TESTDIR/fakemergerecord.py fakemergerecord -X
+  $ hg debugmergestate
+  * version 2 records
+  local: 8f7551c7e4a2f2efe0bc8c741baf7f227d65d758
+  other: e860deea161a2f77de56603b340ebbb4536308ae
+  file: e (record type "F", state "u", hash 58e6b3a414a1e090dfc6029add0f3555ccba127f)
+    local path: e (flags "")
+    ancestor path: e (node 0000000000000000000000000000000000000000)
+    other path: e (node 6b67ccefd5ce6de77e7ead4f5292843a0255329f)
+  unrecognized entry: X	mandatory record
+  $ hg resolve -l
+  abort: unsupported merge state records: X
+  (see https://mercurial-scm.org/wiki/MergeStateRecords for more information)
+  [255]
+  $ hg resolve -ma
+  abort: unsupported merge state records: X
+  (see https://mercurial-scm.org/wiki/MergeStateRecords for more information)
+  [255]
+
+abort the edit (should clear out merge state)
   $ hg histedit --abort 2>&1 | fixbundle
   2 files updated, 0 files merged, 0 files removed, 0 files unresolved
+  $ hg debugmergestate
+  no merge state found
 
 log after abort
   $ hg resolve -l
   $ hg log --graph
   @  changeset:   6:bfa474341cc9
   |  tag:         tip
   |  user:        test
   |  date:        Thu Jan 01 00:00:00 1970 +0000
   |  summary:     does not commute with e
   |
   o  changeset:   5:652413bf663e
   |  user:        test
   |  date:        Thu Jan 01 00:00:00 1970 +0000
   |  summary:     f
   |
   o  changeset:   4:e860deea161a
   |  user:        test
   |  date:        Thu Jan 01 00:00:00 1970 +0000
   |  summary:     e
   |
   o  changeset:   3:055a42cdd887
   |  user:        test
   |  date:        Thu Jan 01 00:00:00 1970 +0000
   |  summary:     d
   |
   o  changeset:   2:177f92b77385
   |  user:        test
   |  date:        Thu Jan 01 00:00:00 1970 +0000
   |  summary:     c
   |
   o  changeset:   1:d2ae7f538514
   |  user:        test
   |  date:        Thu Jan 01 00:00:00 1970 +0000
   |  summary:     b
   |
   o  changeset:   0:cb9a9f314b8b
      user:        test
      date:        Thu Jan 01 00:00:00 1970 +0000
      summary:     a
   
 
   $ cd ..

tests/test-rebase-abort.t

@@ -1,354 +1,392
   $ cat >> $HGRCPATH <<EOF
   > [extensions]
   > rebase=
   > 
   > [phases]
   > publish=False
   > 
   > [alias]
   > tglog = log -G --template "{rev}:{phase} '{desc}' {branches}\n"
   > EOF
 
 
   $ hg init a
   $ cd a
 
   $ touch .hg/rebasestate
   $ hg sum
   parent: -1:000000000000 tip (empty repository)
   branch: default
   commit: (clean)
   update: (current)
   abort: .hg/rebasestate is incomplete
   [255]
   $ rm .hg/rebasestate
 
   $ echo c1 > common
   $ hg add common
   $ hg ci -m C1
 
   $ echo c2 >> common
   $ hg ci -m C2
 
   $ echo c3 >> common
   $ hg ci -m C3
 
   $ hg up -q -C 1
 
   $ echo l1 >> extra
   $ hg add extra
   $ hg ci -m L1
   created new head
 
   $ sed -e 's/c2/l2/' common > common.new
   $ mv common.new common
   $ hg ci -m L2
 
   $ hg phase --force --secret 2
 
   $ hg tglog
   @  4:draft 'L2'
   |
   o  3:draft 'L1'
   |
   | o  2:secret 'C3'
   |/
   o  1:draft 'C2'
   |
   o  0:draft 'C1'
   
 
 Conflicting rebase:
 
   $ hg rebase -s 3 -d 2
   rebasing 3:3163e20567cc "L1"
   rebasing 4:46f0b057b5c0 "L2" (tip)
   merging common
   warning: conflicts while merging common! (edit, then use 'hg resolve --mark')
   unresolved conflicts (see hg resolve, then hg rebase --continue)
   [1]
 
-Abort:
+Insert unsupported advisory merge record:
+
+  $ hg --config extensions.fakemergerecord=$TESTDIR/fakemergerecord.py fakemergerecord -x
+  $ hg debugmergestate
+  * version 2 records
+  local: 3e046f2ecedb793b97ed32108086edd1a162f8bc
+  other: 46f0b057b5c061d276b91491c22151f78698abd2
+  unrecognized entry: x	advisory record
+  file: common (record type "F", state "u", hash 94c8c21d08740f5da9eaa38d1f175c592692f0d1)
+    local path: common (flags "")
+    ancestor path: common (node de0a666fdd9c1a0b0698b90d85064d8bd34f74b6)
+    other path: common (node 2f6411de53677f6f1048fef5bf888d67a342e0a5)
+  $ hg resolve -l
+  U common
+
+Insert unsupported mandatory merge record:
+
+  $ hg --config extensions.fakemergerecord=$TESTDIR/fakemergerecord.py fakemergerecord -X
+  $ hg debugmergestate
+  * version 2 records
+  local: 3e046f2ecedb793b97ed32108086edd1a162f8bc
+  other: 46f0b057b5c061d276b91491c22151f78698abd2
+  file: common (record type "F", state "u", hash 94c8c21d08740f5da9eaa38d1f175c592692f0d1)
+    local path: common (flags "")
+    ancestor path: common (node de0a666fdd9c1a0b0698b90d85064d8bd34f74b6)
+    other path: common (node 2f6411de53677f6f1048fef5bf888d67a342e0a5)
+  unrecognized entry: X	mandatory record
+  $ hg resolve -l
+  abort: unsupported merge state records: X
+  (see https://mercurial-scm.org/wiki/MergeStateRecords for more information)
+  [255]
+  $ hg resolve -ma
+  abort: unsupported merge state records: X
+  (see https://mercurial-scm.org/wiki/MergeStateRecords for more information)
+  [255]
+
+Abort (should clear out unsupported merge state):
 
   $ hg rebase --abort
   saved backup bundle to $TESTTMP/a/.hg/strip-backup/3e046f2ecedb-6beef7d5-backup.hg (glob)
   rebase aborted
+  $ hg debugmergestate
+  no merge state found
 
   $ hg tglog
   @  4:draft 'L2'
   |
   o  3:draft 'L1'
   |
   | o  2:secret 'C3'
   |/
   o  1:draft 'C2'
   |
   o  0:draft 'C1'
   
 Test safety for inconsistent rebase state, which may be created (and
 forgotten) by Mercurial earlier than 2.7. This emulates Mercurial
 earlier than 2.7 by renaming ".hg/rebasestate" temporarily.
 
   $ hg rebase -s 3 -d 2
   rebasing 3:3163e20567cc "L1"
   rebasing 4:46f0b057b5c0 "L2" (tip)
   merging common
   warning: conflicts while merging common! (edit, then use 'hg resolve --mark')
   unresolved conflicts (see hg resolve, then hg rebase --continue)
   [1]
 
   $ mv .hg/rebasestate .hg/rebasestate.back
   $ hg update --quiet --clean 2
   $ hg --config extensions.mq= strip --quiet "destination()"
   $ mv .hg/rebasestate.back .hg/rebasestate
 
   $ hg rebase --continue
   abort: cannot continue inconsistent rebase
   (use "hg rebase --abort" to clear broken state)
   [255]
   $ hg summary | grep '^rebase: '
   rebase: (use "hg rebase --abort" to clear broken state)
   $ hg rebase --abort
   rebase aborted (no revision is removed, only broken state is cleared)
 
   $ cd ..
 
 
 Construct new repo:
 
   $ hg init b
   $ cd b
 
   $ echo a > a
   $ hg ci -Am A
   adding a
 
   $ echo b > b
   $ hg ci -Am B
   adding b
 
   $ echo c > c
   $ hg ci -Am C
   adding c
 
   $ hg up -q 0
 
   $ echo b > b
   $ hg ci -Am 'B bis'
   adding b
   created new head
 
   $ echo c1 > c
   $ hg ci -Am C1
   adding c
 
   $ hg phase --force --secret 1
   $ hg phase --public 1
 
 Rebase and abort without generating new changesets:
 
   $ hg tglog
   @  4:draft 'C1'
   |
   o  3:draft 'B bis'
   |
   | o  2:secret 'C'
   | |
   | o  1:public 'B'
   |/
   o  0:public 'A'
   
   $ hg rebase -b 4 -d 2
   rebasing 3:a6484957d6b9 "B bis"
   note: rebase of 3:a6484957d6b9 created no changes to commit
   rebasing 4:145842775fec "C1" (tip)
   merging c
   warning: conflicts while merging c! (edit, then use 'hg resolve --mark')
   unresolved conflicts (see hg resolve, then hg rebase --continue)
   [1]
 
   $ hg tglog
   @  4:draft 'C1'
   |
   o  3:draft 'B bis'
   |
   | @  2:secret 'C'
   | |
   | o  1:public 'B'
   |/
   o  0:public 'A'
   
   $ hg rebase -a
   rebase aborted
 
   $ hg tglog
   @  4:draft 'C1'
   |
   o  3:draft 'B bis'
   |
   | o  2:secret 'C'
   | |
   | o  1:public 'B'
   |/
   o  0:public 'A'
   
 
   $ cd ..
 
 rebase abort should not leave working copy in a merge state if tip-1 is public
 (issue4082)
 
   $ hg init abortpublic
   $ cd abortpublic
   $ echo a > a && hg ci -Aqm a
   $ hg book master
   $ hg book foo
   $ echo b > b && hg ci -Aqm b
   $ hg up -q master
   $ echo c > c && hg ci -Aqm c
   $ hg phase -p -r .
   $ hg up -q foo
   $ echo C > c && hg ci -Aqm C
   $ hg log -G --template "{rev} {desc} {bookmarks}"
   @  3 C foo
   |
   | o  2 c master
   | |
   o |  1 b
   |/
   o  0 a
   
 
   $ hg rebase -d master -r foo
   rebasing 3:6c0f977a22d8 "C" (tip foo)
   merging c
   warning: conflicts while merging c! (edit, then use 'hg resolve --mark')
   unresolved conflicts (see hg resolve, then hg rebase --continue)
   [1]
   $ hg rebase --abort
   rebase aborted
   $ hg log -G --template "{rev} {desc} {bookmarks}"
   @  3 C foo
   |
   | o  2 c master
   | |
   o |  1 b
   |/
   o  0 a
   
   $ cd ..
 
 Make sure we don't clobber changes in the working directory when the
 user has somehow managed to update to a different revision (issue4009)
 
   $ hg init noupdate
   $ cd noupdate
   $ hg book @
   $ echo original > a
   $ hg add a
   $ hg commit -m a
   $ echo x > b
   $ hg add b
   $ hg commit -m b1
   $ hg up 0
   0 files updated, 0 files merged, 1 files removed, 0 files unresolved
   (leaving bookmark @)
   $ hg book foo
   $ echo y > b
   $ hg add b
   $ hg commit -m b2
   created new head
 
   $ hg rebase -d @ -b foo --tool=internal:fail
   rebasing 2:070cf4580bb5 "b2" (tip foo)
   unresolved conflicts (see hg resolve, then hg rebase --continue)
   [1]
 
   $ mv .hg/rebasestate ./ # so we're allowed to hg up like in mercurial <2.6.3
   $ hg up -C 0            # user does other stuff in the repo
   0 files updated, 0 files merged, 1 files removed, 0 files unresolved
 
   $ mv rebasestate .hg/   # user upgrades to 2.7
 
   $ echo new > a
   $ hg up 1               # user gets an error saying to run hg rebase --abort
   abort: rebase in progress
   (use 'hg rebase --continue' or 'hg rebase --abort')
   [255]
 
   $ cat a
   new
   $ hg rebase --abort
   rebase aborted
   $ cat a
   new
 
   $ cd ..
 
 On the other hand, make sure we *do* clobber changes whenever we
 haven't somehow managed to update the repo to a different revision
 during a rebase (issue4661)
 
   $ hg ini yesupdate
   $ cd yesupdate
   $ echo "initial data" > foo.txt
   $ hg add
   adding foo.txt
   $ hg ci -m "initial checkin"
   $ echo "change 1" > foo.txt
   $ hg ci -m "change 1"
   $ hg up 0
   1 files updated, 0 files merged, 0 files removed, 0 files unresolved
   $ echo "conflicting change 1" > foo.txt
   $ hg ci -m "conflicting 1"
   created new head
   $ echo "conflicting change 2" > foo.txt
   $ hg ci -m "conflicting 2"
 
   $ hg rebase -d 1 --tool 'internal:fail'
   rebasing 2:e4ea5cdc9789 "conflicting 1"
   unresolved conflicts (see hg resolve, then hg rebase --continue)
   [1]
   $ hg rebase --abort
   rebase aborted
   $ hg summary
   parent: 3:b16646383533 tip
    conflicting 2
   branch: default
   commit: (clean)
   update: 1 new changesets, 2 branch heads (merge)
   phases: 4 draft
 
 test aborting a rebase succeeds after rebasing with skipped commits onto a
 public changeset (issue4896)
 
   $ hg init succeedonpublic
   $ cd succeedonpublic
   $ echo 'content' > root
   $ hg commit -A -m 'root' -q
 
 set up public branch
   $ echo 'content' > disappear
   $ hg commit -A -m 'disappear public' -q
 commit will cause merge conflict on rebase
   $ echo '' > root
   $ hg commit -m 'remove content public' -q
   $ hg phase --public
 
 setup the draft branch that will be rebased onto public commit
   $ hg up -r 0 -q
   $ echo 'content' > disappear
 commit will disappear
   $ hg commit -A -m 'disappear draft' -q
   $ echo 'addedcontADDEDentadded' > root
 commit will cause merge conflict on rebase
   $ hg commit -m 'add content draft' -q
 
   $ hg rebase -d 'public()' --tool :merge -q
   note: rebase of 3:0682fd3dabf5 created no changes to commit
   warning: conflicts while merging root! (edit, then use 'hg resolve --mark')
   unresolved conflicts (see hg resolve, then hg rebase --continue)
   [1]
   $ hg rebase --abort
   rebase aborted
 

tests/test-resolve.t

@@ -1,262 +1,322
 test that a commit clears the merge state.
 
   $ hg init repo
   $ cd repo
 
   $ echo foo > file1
   $ echo foo > file2
   $ hg commit -Am 'add files'
   adding file1
   adding file2
 
   $ echo bar >> file1
   $ echo bar >> file2
   $ hg commit -Am 'append bar to files'
 
 create a second head with conflicting edits
 
   $ hg up -C 0
   2 files updated, 0 files merged, 0 files removed, 0 files unresolved
   $ echo baz >> file1
   $ echo baz >> file2
   $ hg commit -Am 'append baz to files'
   created new head
 
 create a third head with no conflicting edits
   $ hg up -qC 0
   $ echo foo > file3
   $ hg commit -Am 'add non-conflicting file'
   adding file3
   created new head
 
 failing merge
 
   $ hg up -qC 2
   $ hg merge --tool=internal:fail 1
   0 files updated, 0 files merged, 0 files removed, 2 files unresolved
   use 'hg resolve' to retry unresolved file merges or 'hg update -C .' to abandon
   [1]
 
 resolve -l should contain unresolved entries
 
   $ hg resolve -l
   U file1
   U file2
 
   $ hg resolve -l --no-status
   file1
   file2
 
 resolving an unknown path should emit a warning, but not for -l
 
   $ hg resolve -m does-not-exist
   arguments do not match paths that need resolving
   $ hg resolve -l does-not-exist
 
 don't allow marking or unmarking driver-resolved files
 
   $ cat > $TESTTMP/markdriver.py << EOF
   > '''mark and unmark files as driver-resolved'''
   > from mercurial import cmdutil, merge, scmutil
   > cmdtable = {}
   > command = cmdutil.command(cmdtable)
   > @command('markdriver',
   >   [('u', 'unmark', None, '')],
   >   'FILE...')
   > def markdriver(ui, repo, *pats, **opts):
   >     wlock = repo.wlock()
   >     try:
   >         ms = merge.mergestate.read(repo)
   >         m = scmutil.match(repo[None], pats, opts)
   >         for f in ms:
   >             if not m(f):
   >                 continue
   >             if not opts['unmark']:
   >                 ms.mark(f, 'd')
   >             else:
   >                 ms.mark(f, 'u')
   >         ms.commit()
   >     finally:
   >         wlock.release()
   > EOF
   $ hg --config extensions.markdriver=$TESTTMP/markdriver.py markdriver file1
   $ hg resolve --list
   D file1
   U file2
   $ hg resolve --mark file1
   not marking file1 as it is driver-resolved
 this should not print out file1
   $ hg resolve --mark --all
   (no more unresolved files -- run "hg resolve --all" to conclude)
   $ hg resolve --mark 'glob:file*'
   (no more unresolved files -- run "hg resolve --all" to conclude)
   $ hg resolve --list
   D file1
   R file2
   $ hg resolve --unmark file1
   not unmarking file1 as it is driver-resolved
   (no more unresolved files -- run "hg resolve --all" to conclude)
   $ hg resolve --unmark --all
   $ hg resolve --list
   D file1
   U file2
   $ hg --config extensions.markdriver=$TESTTMP/markdriver.py markdriver --unmark file1
   $ hg resolve --list
   U file1
   U file2
 
 resolve the failure
 
   $ echo resolved > file1
   $ hg resolve -m file1
 
 resolve -l should show resolved file as resolved
 
   $ hg resolve -l
   R file1
   U file2
 
   $ hg resolve -l -Tjson
   [
    {
     "path": "file1",
     "status": "R"
    },
    {
     "path": "file2",
     "status": "U"
    }
   ]
 
 resolve -m without paths should mark all resolved
 
   $ hg resolve -m
   (no more unresolved files)
   $ hg commit -m 'resolved'
 
 resolve -l should be empty after commit
 
   $ hg resolve -l
 
   $ hg resolve -l -Tjson
   [
   ]
 
 resolve --all should abort when no merge in progress
 
   $ hg resolve --all
   abort: resolve command not applicable when not merging
   [255]
 
 resolve -m should abort when no merge in progress
 
   $ hg resolve -m
   abort: resolve command not applicable when not merging
   [255]
 
 set up conflict-free merge
 
   $ hg up -qC 3
   $ hg merge 1
   2 files updated, 0 files merged, 0 files removed, 0 files unresolved
   (branch merge, don't forget to commit)
 
 resolve --all should do nothing in merge without conflicts
   $ hg resolve --all
   (no more unresolved files)
 
 resolve -m should do nothing in merge without conflicts
 
   $ hg resolve -m
   (no more unresolved files)
 
 get back to conflicting state
 
   $ hg up -qC 2
   $ hg merge --tool=internal:fail 1
   0 files updated, 0 files merged, 0 files removed, 2 files unresolved
   use 'hg resolve' to retry unresolved file merges or 'hg update -C .' to abandon
   [1]
 
 resolve without arguments should suggest --all
   $ hg resolve
   abort: no files or directories specified
   (use --all to re-merge all unresolved files)
   [255]
 
 resolve --all should re-merge all unresolved files
   $ hg resolve --all
   merging file1
   merging file2
   warning: conflicts while merging file1! (edit, then use 'hg resolve --mark')
   warning: conflicts while merging file2! (edit, then use 'hg resolve --mark')
   [1]
   $ cat file1.orig
   foo
   baz
   $ cat file2.orig
   foo
   baz
 
 .orig files should exists where specified
   $ hg resolve --all --verbose --config 'ui.origbackuppath=.hg/origbackups'
   merging file1
   creating directory: $TESTTMP/repo/.hg/origbackups (glob)
   merging file2
   warning: conflicts while merging file1! (edit, then use 'hg resolve --mark')
   warning: conflicts while merging file2! (edit, then use 'hg resolve --mark')
   [1]
   $ ls .hg/origbackups
   file1.orig
   file2.orig
   $ grep '<<<' file1 > /dev/null
   $ grep '<<<' file2 > /dev/null
 
 resolve <file> should re-merge file
   $ echo resolved > file1
   $ hg resolve -q file1
   warning: conflicts while merging file1! (edit, then use 'hg resolve --mark')
   [1]
   $ grep '<<<' file1 > /dev/null
 
 test .orig behavior with resolve
 
   $ hg resolve -q file1 --tool 'f --dump $TESTTMP/repo/file1.orig'
   */file1~base*: (glob)
   >>>
   foo
   <<<
   */file1~other*: (glob)
   >>>
   foo
   bar
   <<<
   $TESTTMP/repo/file1: (glob)
   >>>
   foo
   baz
   <<<
   $TESTTMP/repo/file1.orig: (glob)
   >>>
   foo
   baz
   <<<
 
 resolve <file> should do nothing if 'file' was marked resolved
   $ echo resolved > file1
   $ hg resolve -m file1
   $ hg resolve -q file1
   $ cat file1
   resolved
 
+insert unsupported advisory merge record
+
+  $ hg --config extensions.fakemergerecord=$TESTDIR/fakemergerecord.py fakemergerecord -x
+  $ hg debugmergestate
+  * version 2 records
+  local: 57653b9f834a4493f7240b0681efcb9ae7cab745
+  other: dc77451844e37f03f5c559e3b8529b2b48d381d1
+  unrecognized entry: x	advisory record
+  file: file1 (record type "F", state "r", hash 60b27f004e454aca81b0480209cce5081ec52390)
+    local path: file1 (flags "")
+    ancestor path: file1 (node 2ed2a3912a0b24502043eae84ee4b279c18b90dd)
+    other path: file1 (node 6f4310b00b9a147241b071a60c28a650827fb03d)
+  file: file2 (record type "F", state "u", hash cb99b709a1978bd205ab9dfd4c5aaa1fc91c7523)
+    local path: file2 (flags "")
+    ancestor path: file2 (node 2ed2a3912a0b24502043eae84ee4b279c18b90dd)
+    other path: file2 (node 6f4310b00b9a147241b071a60c28a650827fb03d)
+  $ hg resolve -l
+  R file1
+  U file2
+
+insert unsupported mandatory merge record
+
+  $ hg --config extensions.fakemergerecord=$TESTDIR/fakemergerecord.py fakemergerecord -X
+  $ hg debugmergestate
+  * version 2 records
+  local: 57653b9f834a4493f7240b0681efcb9ae7cab745
+  other: dc77451844e37f03f5c559e3b8529b2b48d381d1
+  file: file1 (record type "F", state "r", hash 60b27f004e454aca81b0480209cce5081ec52390)
+    local path: file1 (flags "")
+    ancestor path: file1 (node 2ed2a3912a0b24502043eae84ee4b279c18b90dd)
+    other path: file1 (node 6f4310b00b9a147241b071a60c28a650827fb03d)
+  file: file2 (record type "F", state "u", hash cb99b709a1978bd205ab9dfd4c5aaa1fc91c7523)
+    local path: file2 (flags "")
+    ancestor path: file2 (node 2ed2a3912a0b24502043eae84ee4b279c18b90dd)
+    other path: file2 (node 6f4310b00b9a147241b071a60c28a650827fb03d)
+  unrecognized entry: X	mandatory record
+  $ hg resolve -l
+  abort: unsupported merge state records: X
+  (see https://mercurial-scm.org/wiki/MergeStateRecords for more information)
+  [255]
+  $ hg resolve -ma
+  abort: unsupported merge state records: X
+  (see https://mercurial-scm.org/wiki/MergeStateRecords for more information)
+  [255]
+  $ hg summary
+  parent: 2:57653b9f834a 
+   append baz to files
+  parent: 1:dc77451844e3 
+   append bar to files
+  branch: default
+  warning: merge state has unsupported record types: X
+  commit: 2 modified, 2 unknown (merge)
+  update: 2 new changesets (update)
+  phases: 5 draft
+
+update --clean shouldn't abort on unsupported records
+
+  $ hg up -qC 1
+  $ hg debugmergestate
+  no merge state found
+
 test crashed merge with empty mergestate
 
-  $ hg up -qC 1
   $ mkdir .hg/merge
   $ touch .hg/merge/state
 
 resolve -l should be empty
 
   $ hg resolve -l
 
   $ cd ..