rebase: exclude descendants of obsoletes w/o a successor in dest (
issue5300)
.. feature::
Let 'hg rebase' avoid content-divergence by skipping obsolete
changesets (and their descendants) when they are present in the rebase
set along with one of their successors but none of their successors is
in destination.
In the following example, when trying to rebase 3:: onto 2, the rebase
will abort with "this rebase will cause divergence from: 4":
o 7 f
|
| o 6 e
| |
| o 5 d'
| |
x | 4 d (rewritten as 5)
|/
o 3 c
|
| o 2 x
| |
o | 1 b
|/
o 0 a
By excluding obsolete changesets without a successor in destination (4
in the example above) and their descendants, we make rebase work in this
case, thus giving:
o 11 e
|
o 10 d'
|
o 9 c
|
o 8 b
|
| o 7 f
| |
| | x 6 e (rewritten using rebase as 11)
| | |
| | x 5 d' (rewritten using rebase as 10)
| | |
| x | 4 d
| |/
| x 3 c (rewritten using rebase as 9)
| |
o | 2 x
| |
| x 1 b (rewritten using rebase as 8)
|/
o 0 a
where branch 4:: is left behind while branch 5:: is rebased as expected.
The rationale is that users may not be interested in rebasing orphan
changesets when specifying a rebase set that include them but would
still want "stable" ones to be rebased. Currently, the user is suggested
to allow divergence (but probably does not want it) or they must specify
a rebase set excluding problematic changesets (which might be a bit
cumbersome). The approach proposed here corresponds to "Option 2" in
https://www.mercurial-scm.org/wiki/CEDRebase.
We extend _computeobsoletenotrebased() so that it also return a set of
obsolete changesets in rebase set without a successor in destination but
with at least one successor in rebase set. This
'obsoletewithoutsuccessorindestination' is then stored as an attribute
of rebaseruntime and used in _performrebasesubset() to:
* filter out descendants of these changesets from the revisions to
rebase;
* issue a message about these revisions being skipped.
This only occurs if 'evolution.allowdivergence' option is off and
'rebaseskipobsolete' is on.
# statichttprepo.py - simple http repository class for mercurial
#
# This provides read-only repo access to repositories exported via static http
#
# Copyright 2005-2007 Matt Mackall <mpm@selenic.com>
#
# 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 (
byterange,
changelog,
error,
localrepo,
manifest,
namespaces,
pathutil,
scmutil,
store,
url,
util,
vfs as vfsmod,
)
urlerr = util.urlerr
urlreq = util.urlreq
class httprangereader(object):
def __init__(self, url, opener):
# we assume opener has HTTPRangeHandler
self.url = url
self.pos = 0
self.opener = opener
self.name = url
def __enter__(self):
return self
def __exit__(self, exc_type, exc_value, traceback):
self.close()
def seek(self, pos):
self.pos = pos
def read(self, bytes=None):
req = urlreq.request(self.url)
end = ''
if bytes:
end = self.pos + bytes - 1
if self.pos or end:
req.add_header('Range', 'bytes=%d-%s' % (self.pos, end))
try:
f = self.opener.open(req)
data = f.read()
code = f.code
except urlerr.httperror as inst:
num = inst.code == 404 and errno.ENOENT or None
raise IOError(num, inst)
except urlerr.urlerror as inst:
raise IOError(None, inst.reason[1])
if code == 200:
# HTTPRangeHandler does nothing if remote does not support
# Range headers and returns the full entity. Let's slice it.
if bytes:
data = data[self.pos:self.pos + bytes]
else:
data = data[self.pos:]
elif bytes:
data = data[:bytes]
self.pos += len(data)
return data
def readlines(self):
return self.read().splitlines(True)
def __iter__(self):
return iter(self.readlines())
def close(self):
pass
def build_opener(ui, authinfo):
# urllib cannot handle URLs with embedded user or passwd
urlopener = url.opener(ui, authinfo)
urlopener.add_handler(byterange.HTTPRangeHandler())
class statichttpvfs(vfsmod.abstractvfs):
def __init__(self, base):
self.base = base
def __call__(self, path, mode='r', *args, **kw):
if mode not in ('r', 'rb'):
raise IOError('Permission denied')
f = "/".join((self.base, urlreq.quote(path)))
return httprangereader(f, urlopener)
def join(self, path):
if path:
return pathutil.join(self.base, path)
else:
return self.base
return statichttpvfs
class statichttppeer(localrepo.localpeer):
def local(self):
return None
def canpush(self):
return False
class statichttprepository(localrepo.localrepository):
supported = localrepo.localrepository._basesupported
def __init__(self, ui, path):
self._url = path
self.ui = ui
self.root = path
u = util.url(path.rstrip('/') + "/.hg")
self.path, authinfo = u.authinfo()
vfsclass = build_opener(ui, authinfo)
self.vfs = vfsclass(self.path)
self.cachevfs = vfsclass(self.vfs.join('cache'))
self._phasedefaults = []
self.names = namespaces.namespaces()
self.filtername = None
try:
requirements = scmutil.readrequires(self.vfs, self.supported)
except IOError as inst:
if inst.errno != errno.ENOENT:
raise
requirements = set()
# check if it is a non-empty old-style repository
try:
fp = self.vfs("00changelog.i")
fp.read(1)
fp.close()
except IOError as inst:
if inst.errno != errno.ENOENT:
raise
# we do not care about empty old-style repositories here
msg = _("'%s' does not appear to be an hg repository") % path
raise error.RepoError(msg)
# setup store
self.store = store.store(requirements, self.path, vfsclass)
self.spath = self.store.path
self.svfs = self.store.opener
self.sjoin = self.store.join
self._filecache = {}
self.requirements = requirements
self.manifestlog = manifest.manifestlog(self.svfs, self)
self.changelog = changelog.changelog(self.svfs)
self._tags = None
self.nodetagscache = None
self._branchcaches = {}
self._revbranchcache = None
self.encodepats = None
self.decodepats = None
self._transref = None
# Cache of types representing filtered repos.
self._filteredrepotypes = {}
def _restrictcapabilities(self, caps):
caps = super(statichttprepository, self)._restrictcapabilities(caps)
return caps.difference(["pushkey"])
def url(self):
return self._url
def local(self):
return False
def peer(self):
return statichttppeer(self)
def wlock(self, wait=True):
raise error.LockUnavailable(0, _('lock not available'), 'lock',
_('cannot lock static-http repository'))
def lock(self, wait=True):
raise error.Abort(_('cannot lock static-http repository'))
def _writecaches(self):
pass # statichttprepository are read only
def instance(ui, path, create):
if create:
raise error.Abort(_('cannot create new static-http repository'))
return statichttprepository(ui, path[7:])