##// END OF EJS Templates
tracked-key: remove the dual write and rename to tracked-hint...
tracked-key: remove the dual write and rename to tracked-hint The dual-write approach was mostly useless. As explained in the previous version of the help, the key had to be read twice before we could cache a value. However this "read twice" limitation actually also apply to any usage of the key. If some operation wants to rely of the "same value == same tracked set" property it would need to read the value before, and after running that operation (or at least, after, in all cases). So it cannot be sure the operation it did is "valid" until checking the key after the operation. As a resultat such operation can only be read-only or rollbackable. This reduce the utility of the "same value == same tracked set" a lot. So it seems simpler to drop the double write and to update the documentation to highlight that this file does not garantee race-free operation. As a result the "key" is demoted to a "hint". Documentation is updated accordingly. Differential Revision: https://phab.mercurial-scm.org/D12201

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unionrepo.py
316 lines | 9.7 KiB | text/x-python | PythonLexer
# unionrepo.py - repository class for viewing union of repository changesets
#
# Derived from bundlerepo.py
# Copyright 2006, 2007 Benoit Boissinot <bboissin@gmail.com>
# Copyright 2013 Unity Technologies, Mads Kiilerich <madski@unity3d.com>
#
# This software may be used and distributed according to the terms of the
# GNU General Public License version 2 or any later version.
"""Repository class for "in-memory pull" of one local repository to another,
allowing operations like diff and log with revsets.
"""
from __future__ import absolute_import
from .i18n import _
from .pycompat import getattr
from . import (
changelog,
cmdutil,
encoding,
error,
filelog,
localrepo,
manifest,
mdiff,
pathutil,
revlog,
util,
vfs as vfsmod,
)
from .revlogutils import (
constants as revlog_constants,
)
class unionrevlog(revlog.revlog):
def __init__(self, opener, radix, revlog2, linkmapper):
# How it works:
# To retrieve a revision, we just need to know the node id so we can
# look it up in revlog2.
#
# To differentiate a rev in the second revlog from a rev in the revlog,
# we check revision against repotiprev.
opener = vfsmod.readonlyvfs(opener)
target = getattr(revlog2, 'target', None)
if target is None:
# a revlog wrapper, eg: the manifestlog that is not an actual revlog
target = revlog2._revlog.target
revlog.revlog.__init__(self, opener, target=target, radix=radix)
self.revlog2 = revlog2
n = len(self)
self.repotiprev = n - 1
self.bundlerevs = set() # used by 'bundle()' revset expression
for rev2 in self.revlog2:
rev = self.revlog2.index[rev2]
# rev numbers - in revlog2, very different from self.rev
(
_start,
_csize,
rsize,
base,
linkrev,
p1rev,
p2rev,
node,
_sdo,
_sds,
_dcm,
_sdcm,
rank,
) = rev
flags = _start & 0xFFFF
if linkmapper is None: # link is to same revlog
assert linkrev == rev2 # we never link back
link = n
else: # rev must be mapped from repo2 cl to unified cl by linkmapper
link = linkmapper(linkrev)
if linkmapper is not None: # link is to same revlog
base = linkmapper(base)
this_rev = self.index.get_rev(node)
if this_rev is not None:
# this happens for the common revlog revisions
self.bundlerevs.add(this_rev)
continue
p1node = self.revlog2.node(p1rev)
p2node = self.revlog2.node(p2rev)
# TODO: it's probably wrong to set compressed length to -1, but
# I have no idea if csize is valid in the base revlog context.
e = (
flags,
-1,
rsize,
base,
link,
self.rev(p1node),
self.rev(p2node),
node,
0, # sidedata offset
0, # sidedata size
revlog_constants.COMP_MODE_INLINE,
revlog_constants.COMP_MODE_INLINE,
rank,
)
self.index.append(e)
self.bundlerevs.add(n)
n += 1
def _chunk(self, rev):
if rev <= self.repotiprev:
return revlog.revlog._chunk(self, rev)
return self.revlog2._chunk(self.node(rev))
def revdiff(self, rev1, rev2):
"""return or calculate a delta between two revisions"""
if rev1 > self.repotiprev and rev2 > self.repotiprev:
return self.revlog2.revdiff(
self.revlog2.rev(self.node(rev1)),
self.revlog2.rev(self.node(rev2)),
)
elif rev1 <= self.repotiprev and rev2 <= self.repotiprev:
return super(unionrevlog, self).revdiff(rev1, rev2)
return mdiff.textdiff(self.rawdata(rev1), self.rawdata(rev2))
def _revisiondata(self, nodeorrev, _df=None, raw=False):
if isinstance(nodeorrev, int):
rev = nodeorrev
node = self.node(rev)
else:
node = nodeorrev
rev = self.rev(node)
if rev > self.repotiprev:
# work around manifestrevlog NOT being a revlog
revlog2 = getattr(self.revlog2, '_revlog', self.revlog2)
func = revlog2._revisiondata
else:
func = super(unionrevlog, self)._revisiondata
return func(node, _df=_df, raw=raw)
def addrevision(self, text, transaction, link, p1=None, p2=None, d=None):
raise NotImplementedError
def addgroup(
self,
deltas,
linkmapper,
transaction,
alwayscache=False,
addrevisioncb=None,
duplicaterevisioncb=None,
maybemissingparents=False,
):
raise NotImplementedError
def strip(self, minlink, transaction):
raise NotImplementedError
def checksize(self):
raise NotImplementedError
class unionchangelog(unionrevlog, changelog.changelog):
def __init__(self, opener, opener2):
changelog.changelog.__init__(self, opener)
linkmapper = None
changelog2 = changelog.changelog(opener2)
unionrevlog.__init__(self, opener, self.radix, changelog2, linkmapper)
class unionmanifest(unionrevlog, manifest.manifestrevlog):
def __init__(self, nodeconstants, opener, opener2, linkmapper):
manifest.manifestrevlog.__init__(self, nodeconstants, opener)
manifest2 = manifest.manifestrevlog(nodeconstants, opener2)
unionrevlog.__init__(
self, opener, self._revlog.radix, manifest2, linkmapper
)
class unionfilelog(filelog.filelog):
def __init__(self, opener, path, opener2, linkmapper, repo):
filelog.filelog.__init__(self, opener, path)
filelog2 = filelog.filelog(opener2, path)
self._revlog = unionrevlog(
opener, self._revlog.radix, filelog2._revlog, linkmapper
)
self._repo = repo
self.repotiprev = self._revlog.repotiprev
self.revlog2 = self._revlog.revlog2
def iscensored(self, rev):
"""Check if a revision is censored."""
if rev <= self.repotiprev:
return filelog.filelog.iscensored(self, rev)
node = self.node(rev)
return self.revlog2.iscensored(self.revlog2.rev(node))
class unionpeer(localrepo.localpeer):
def canpush(self):
return False
class unionrepository(object):
"""Represents the union of data in 2 repositories.
Instances are not usable if constructed directly. Use ``instance()``
or ``makeunionrepository()`` to create a usable instance.
"""
def __init__(self, repo2, url):
self.repo2 = repo2
self._url = url
self.ui.setconfig(b'phases', b'publish', False, b'unionrepo')
@localrepo.unfilteredpropertycache
def changelog(self):
return unionchangelog(self.svfs, self.repo2.svfs)
@localrepo.unfilteredpropertycache
def manifestlog(self):
rootstore = unionmanifest(
self.nodeconstants,
self.svfs,
self.repo2.svfs,
self.unfiltered()._clrev,
)
return manifest.manifestlog(
self.svfs, self, rootstore, self.narrowmatch()
)
def _clrev(self, rev2):
"""map from repo2 changelog rev to temporary rev in self.changelog"""
node = self.repo2.changelog.node(rev2)
return self.changelog.rev(node)
def url(self):
return self._url
def file(self, f):
return unionfilelog(
self.svfs, f, self.repo2.svfs, self.unfiltered()._clrev, self
)
def close(self):
self.repo2.close()
def cancopy(self):
return False
def peer(self):
return unionpeer(self)
def getcwd(self):
return encoding.getcwd() # always outside the repo
def instance(ui, path, create, intents=None, createopts=None):
if create:
raise error.Abort(_(b'cannot create new union repository'))
parentpath = ui.config(b"bundle", b"mainreporoot")
if not parentpath:
# try to find the correct path to the working directory repo
parentpath = cmdutil.findrepo(encoding.getcwd())
if parentpath is None:
parentpath = b''
if parentpath:
# Try to make the full path relative so we get a nice, short URL.
# In particular, we don't want temp dir names in test outputs.
cwd = encoding.getcwd()
if parentpath == cwd:
parentpath = b''
else:
cwd = pathutil.normasprefix(cwd)
if parentpath.startswith(cwd):
parentpath = parentpath[len(cwd) :]
if path.startswith(b'union:'):
s = path.split(b":", 1)[1].split(b"+", 1)
if len(s) == 1:
repopath, repopath2 = parentpath, s[0]
else:
repopath, repopath2 = s
else:
repopath, repopath2 = parentpath, path
return makeunionrepository(ui, repopath, repopath2)
def makeunionrepository(ui, repopath1, repopath2):
"""Make a union repository object from 2 local repo paths."""
repo1 = localrepo.instance(ui, repopath1, create=False)
repo2 = localrepo.instance(ui, repopath2, create=False)
url = b'union:%s+%s' % (
util.expandpath(repopath1),
util.expandpath(repopath2),
)
class derivedunionrepository(unionrepository, repo1.__class__):
pass
repo = repo1
repo.__class__ = derivedunionrepository
unionrepository.__init__(repo1, repo2, url)
return repo