Mercurial > hg
view mercurial/unionrepo.py @ 39604:335ae4d0a552
bundlerepo: dynamically create repository type from base repository
Previously, bundlerepository inherited from localrepo.localrepository.
You simply instantiated a bundlerepository and its __init__ called
localrepo.localrepository.__init__. Things were simple.
Unfortunately, this strategy is limiting because it assumes that
the base repository is a localrepository instance. And it assumes
various properties of localrepository, such as the arguments its
__init__ takes. And it prevents us from changing behavior of
localrepository.__init__ without also having to change derived classes.
Previous and ongoing work to abstract storage revealed these
limitations.
This commit changes the initialization strategy of bundle repositories
to dynamically create a type to represent the repository. Instead of
a static type, we instantiate a new local repo instance via
localrepo.instance(). We then combine its __class__ with
bundlerepository to produce a new type. This ensures that no matter
how localrepo.instance() decides to create a repository object, we
can derive a bundle repo object from it. i.e. localrepo.instance()
could return a type that isn't a localrepository and it would "just
work."
Well, it would "just work" if bundlerepository's custom implementations
only accessed attributes in the documented repository interface. I'm
pretty sure it violates the interface contract in a handful of
places. But we can worry about that another day. This change gets us
closer to doing more clever things around instantiating repository
instances without having to worry about teaching bundlerepository about
them.
.. api::
``bundlerepo.bundlerepository`` is no longer usable on its own.
The class is combined with the class of the base repository it is
associated with at run-time.
New bundlerepository instances can be obtained by calling
``bundlerepo.instance()`` or ``bundlerepo.makebundlerepository()``.
Differential Revision: https://phab.mercurial-scm.org/D4555
author | Gregory Szorc <gregory.szorc@gmail.com> |
---|---|
date | Tue, 11 Sep 2018 19:50:07 -0700 |
parents | 089fc0db0954 |
children | 23f2299e9e53 |
line wrap: on
line source
# 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 .node import nullid from . import ( changelog, cmdutil, error, filelog, localrepo, manifest, mdiff, pathutil, pycompat, revlog, util, vfs as vfsmod, ) class unionrevlog(revlog.revlog): def __init__(self, opener, indexfile, 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) revlog.revlog.__init__(self, opener, indexfile) 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 = 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) if node in self.nodemap: # this happens for the common revlog revisions self.bundlerevs.add(self.nodemap[node]) continue p1node = self.revlog2.node(p1rev) p2node = self.revlog2.node(p2rev) # TODO: it's probably wrong to set compressed length to None, but # I have no idea if csize is valid in the base revlog context. e = (flags, None, rsize, base, link, self.rev(p1node), self.rev(p2node), node) self.index.append(e) self.nodemap[node] = n 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 self.baserevdiff(rev1, rev2) return mdiff.textdiff(self.revision(rev1), self.revision(rev2)) def revision(self, nodeorrev, _df=None, raw=False): """return an uncompressed revision of a given node or revision number. """ if isinstance(nodeorrev, int): rev = nodeorrev node = self.node(rev) else: node = nodeorrev rev = self.rev(node) if node == nullid: return "" if rev > self.repotiprev: text = self.revlog2.revision(node) self._cache = (node, rev, text) else: text = self.baserevision(rev) # already cached return text def baserevision(self, nodeorrev): # Revlog subclasses may override 'revision' method to modify format of # content retrieved from revlog. To use unionrevlog with such class one # needs to override 'baserevision' and make more specific call here. return revlog.revlog.revision(self, nodeorrev) def baserevdiff(self, rev1, rev2): # Exists for the same purpose as baserevision. return revlog.revlog.revdiff(self, rev1, rev2) def addrevision(self, text, transaction, link, p1=None, p2=None, d=None): raise NotImplementedError def addgroup(self, deltas, transaction, addrevisioncb=None): raise NotImplementedError def strip(self, rev, minlink): 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.indexfile, changelog2, linkmapper) def baserevision(self, nodeorrev): # Although changelog doesn't override 'revision' method, some extensions # may replace this class with another that does. Same story with # manifest and filelog classes. return changelog.changelog.revision(self, nodeorrev) def baserevdiff(self, rev1, rev2): return changelog.changelog.revdiff(self, rev1, rev2) class unionmanifest(unionrevlog, manifest.manifestrevlog): def __init__(self, opener, opener2, linkmapper): manifest.manifestrevlog.__init__(self, opener) manifest2 = manifest.manifestrevlog(opener2) unionrevlog.__init__(self, opener, self.indexfile, manifest2, linkmapper) def baserevision(self, nodeorrev): return manifest.manifestrevlog.revision(self, nodeorrev) def baserevdiff(self, rev1, rev2): return manifest.manifestrevlog.revdiff(self, rev1, rev2) 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.indexfile, filelog2._revlog, linkmapper) self._repo = repo self.repotiprev = self._revlog.repotiprev self.revlog2 = self._revlog.revlog2 def baserevision(self, nodeorrev): return filelog.filelog.revision(self, nodeorrev) def baserevdiff(self, rev1, rev2): return filelog.filelog.revdiff(self, rev1, rev2) 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(localrepo.localrepository): def __init__(self, ui, path, path2): localrepo.localrepository.__init__(self, ui, path) self.ui.setconfig('phases', 'publish', False, 'unionrepo') self._url = 'union:%s+%s' % (util.expandpath(path), util.expandpath(path2)) self.repo2 = localrepo.localrepository(ui, path2) @localrepo.unfilteredpropertycache def changelog(self): return unionchangelog(self.svfs, self.repo2.svfs) 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 _constructmanifest(self): return unionmanifest(self.svfs, self.repo2.svfs, self.unfiltered()._clrev) 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 pycompat.getcwd() # always outside the repo def instance(ui, path, create, intents=None, createopts=None): if create: raise error.Abort(_('cannot create new union repository')) parentpath = ui.config("bundle", "mainreporoot") if not parentpath: # try to find the correct path to the working directory repo parentpath = cmdutil.findrepo(pycompat.getcwd()) if parentpath is None: parentpath = '' 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 = pycompat.getcwd() if parentpath == cwd: parentpath = '' else: cwd = pathutil.normasprefix(cwd) if parentpath.startswith(cwd): parentpath = parentpath[len(cwd):] if path.startswith('union:'): s = path.split(":", 1)[1].split("+", 1) if len(s) == 1: repopath, repopath2 = parentpath, s[0] else: repopath, repopath2 = s else: repopath, repopath2 = parentpath, path return unionrepository(ui, repopath, repopath2)