mercurial/unionrepo.py
author Martin von Zweigbergk <martinvonz@google.com>
Fri, 21 Jun 2019 16:59:29 -0700
changeset 42590 ab416b5d9b91
parent 42196 94e2f8437f6b
child 42726 64387cd2bf4d
permissions -rw-r--r--
tests: add more tests of copy tracing with removed and re-added files We had a test where the destination of a copy was removed and then added back. This patch adds similar cases where the break in history instead happens to the source file. There are three versions of this: 1. The break happens before the rename. 2. The break happens on a branch parallel to the rename (where copy tracing is done via the merge base) 3. The source is added on each side of the merge base. The break in history is thus in the form of a deletion when going backwards to the merge base and the re-add happens on the other branch. I've also added calls to `hg graft` in these cases to show the breakage in issue 6163. Another factor in these cases is matching nodeid (checked in copies._tracefile()). I've made two copies each of the cases to show the impact of that. One of these is the same as a test in test-rename-merge1.t, so I also deleted that test from there. Some of these tests currently fail, where "fail" is based on my current thinking of how things should work. I had initially thought that we should be more strict about not tracing copies across commits where the file did not exist, but issue 6163 made me reconsider. The only test case here that behaved differently in 4.9 is the exact case reported in issue 6163. Differential Revision: https://phab.mercurial-scm.org/D6599

# 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,
    encoding,
    error,
    filelog,
    localrepo,
    manifest,
    mdiff,
    pathutil,
    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._revisioncache = (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, linkmapper, transaction, addrevisioncb=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.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(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('phases', 'publish', False, 'unionrepo')

    @localrepo.unfilteredpropertycache
    def changelog(self):
        return unionchangelog(self.svfs, self.repo2.svfs)

    @localrepo.unfilteredpropertycache
    def manifestlog(self):
        rootstore = unionmanifest(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(_('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(encoding.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 = encoding.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 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 = '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