hgext/convert/hg.py

convert: use None value for missing files instead of overloading IOError

The internal API used IOError to indicate that a file should be marked as
removed.

There is some correlation between IOError (especially with ENOENT) and files
that should be removed, but using IOErrors to represent file removal internally
required some hacks.

Instead, use the value None to indicate that the file not is present.

Before, spurious IO errors could cause commits that silently removed files.
They will now be reported like all other IO errors so the root cause can be
fixed.

# hg.py - hg backend for convert extension
#
#  Copyright 2005-2009 Matt Mackall <[e-mail]> and others
#
# This software may be used and distributed according to the terms of the
# GNU General Public License version 2 or any later version.

# Notes for hg->hg conversion:
#
# * Old versions of Mercurial didn't trim the whitespace from the ends
#   of commit messages, but new versions do.  Changesets created by
#   those older versions, then converted, may thus have different
#   hashes for changesets that are otherwise identical.
#
# * Using "--config convert.hg.saverev=true" will make the source
#   identifier to be stored in the converted revision. This will cause
#   the converted revision to have a different identity than the
#   source.


import os, time, cStringIO
from mercurial.i18n import _
from mercurial.node import bin, hex, nullid
from mercurial import hg, util, context, bookmarks, error, scmutil

from common import NoRepo, commit, converter_source, converter_sink

import re
sha1re = re.compile(r'\b[0-9a-f]{6,40}\b')

class mercurial_sink(converter_sink):
    def __init__(self, ui, path):
        converter_sink.__init__(self, ui, path)
        self.branchnames = ui.configbool('convert', 'hg.usebranchnames', True)
        self.clonebranches = ui.configbool('convert', 'hg.clonebranches', False)
        self.tagsbranch = ui.config('convert', 'hg.tagsbranch', 'default')
        self.lastbranch = None
        if os.path.isdir(path) and len(os.listdir(path)) > 0:
            try:
                self.repo = hg.repository(self.ui, path)
                if not self.repo.local():
                    raise NoRepo(_('%s is not a local Mercurial repository')
                                 % path)
            except error.RepoError, err:
                ui.traceback()
                raise NoRepo(err.args[0])
        else:
            try:
                ui.status(_('initializing destination %s repository\n') % path)
                self.repo = hg.repository(self.ui, path, create=True)
                if not self.repo.local():
                    raise NoRepo(_('%s is not a local Mercurial repository')
                                 % path)
                self.created.append(path)
            except error.RepoError:
                ui.traceback()
                raise NoRepo(_("could not create hg repository %s as sink")
                             % path)
        self.lock = None
        self.wlock = None
        self.filemapmode = False

    def before(self):
        self.ui.debug('run hg sink pre-conversion action\n')
        self.wlock = self.repo.wlock()
        self.lock = self.repo.lock()

    def after(self):
        self.ui.debug('run hg sink post-conversion action\n')
        if self.lock:
            self.lock.release()
        if self.wlock:
            self.wlock.release()

    def revmapfile(self):
        return self.repo.join("shamap")

    def authorfile(self):
        return self.repo.join("authormap")

    def setbranch(self, branch, pbranches):
        if not self.clonebranches:
            return

        setbranch = (branch != self.lastbranch)
        self.lastbranch = branch
        if not branch:
            branch = 'default'
        pbranches = [(b[0], b[1] and b[1] or 'default') for b in pbranches]
        pbranch = pbranches and pbranches[0][1] or 'default'

        branchpath = os.path.join(self.path, branch)
        if setbranch:
            self.after()
            try:
                self.repo = hg.repository(self.ui, branchpath)
            except Exception:
                self.repo = hg.repository(self.ui, branchpath, create=True)
            self.before()

        # pbranches may bring revisions from other branches (merge parents)
        # Make sure we have them, or pull them.
        missings = {}
        for b in pbranches:
            try:
                self.repo.lookup(b[0])
            except Exception:
                missings.setdefault(b[1], []).append(b[0])

        if missings:
            self.after()
            for pbranch, heads in sorted(missings.iteritems()):
                pbranchpath = os.path.join(self.path, pbranch)
                prepo = hg.peer(self.ui, {}, pbranchpath)
                self.ui.note(_('pulling from %s into %s\n') % (pbranch, branch))
                self.repo.pull(prepo, [prepo.lookup(h) for h in heads])
            self.before()

    def _rewritetags(self, source, revmap, data):
        fp = cStringIO.StringIO()
        for line in data.splitlines():
            s = line.split(' ', 1)
            if len(s) != 2:
                continue
            revid = revmap.get(source.lookuprev(s[0]))
            if not revid:
                continue
            fp.write('%s %s\n' % (revid, s[1]))
        return fp.getvalue()

    def putcommit(self, files, copies, parents, commit, source, revmap):

        files = dict(files)
        def getfilectx(repo, memctx, f):
            v = files[f]
            data, mode = source.getfile(f, v)
            if data is None:
                return None
            if f == '.hgtags':
                data = self._rewritetags(source, revmap, data)
            return context.memfilectx(self.repo, f, data, 'l' in mode,
                                      'x' in mode, copies.get(f))

        pl = []
        for p in parents:
            if p not in pl:
                pl.append(p)
        parents = pl
        nparents = len(parents)
        if self.filemapmode and nparents == 1:
            m1node = self.repo.changelog.read(bin(parents[0]))[0]
            parent = parents[0]

        if len(parents) < 2:
            parents.append(nullid)
        if len(parents) < 2:
            parents.append(nullid)
        p2 = parents.pop(0)

        text = commit.desc

        sha1s = re.findall(sha1re, text)
        for sha1 in sha1s:
            oldrev = source.lookuprev(sha1)
            newrev = revmap.get(oldrev)
            if newrev is not None:
                text = text.replace(sha1, newrev[:len(sha1)])

        extra = commit.extra.copy()

        for label in ('source', 'transplant_source', 'rebase_source'):
            node = extra.get(label)

            if node is None:
                continue

            # Only transplant stores its reference in binary
            if label == 'transplant_source':
                node = hex(node)

            newrev = revmap.get(node)
            if newrev is not None:
                if label == 'transplant_source':
                    newrev = bin(newrev)

                extra[label] = newrev

        if self.branchnames and commit.branch:
            extra['branch'] = commit.branch
        if commit.rev:
            extra['convert_revision'] = commit.rev

        while parents:
            p1 = p2
            p2 = parents.pop(0)
            ctx = context.memctx(self.repo, (p1, p2), text, files.keys(),
                                 getfilectx, commit.author, commit.date, extra)
            self.repo.commitctx(ctx)
            text = "(octopus merge fixup)\n"
            p2 = hex(self.repo.changelog.tip())

        if self.filemapmode and nparents == 1:
            man = self.repo.manifest
            mnode = self.repo.changelog.read(bin(p2))[0]
            closed = 'close' in commit.extra
            if not closed and not man.cmp(m1node, man.revision(mnode)):
                self.ui.status(_("filtering out empty revision\n"))
                self.repo.rollback(force=True)
                return parent
        return p2

    def puttags(self, tags):
        try:
            parentctx = self.repo[self.tagsbranch]
            tagparent = parentctx.node()
        except error.RepoError:
            parentctx = None
            tagparent = nullid

        oldlines = set()
        for branch, heads in self.repo.branchmap().iteritems():
            for h in heads:
                if '.hgtags' in self.repo[h]:
                    oldlines.update(
                        set(self.repo[h]['.hgtags'].data().splitlines(True)))
        oldlines = sorted(list(oldlines))

        newlines = sorted([("%s %s\n" % (tags[tag], tag)) for tag in tags])
        if newlines == oldlines:
            return None, None

        # if the old and new tags match, then there is nothing to update
        oldtags = set()
        newtags = set()
        for line in oldlines:
            s = line.strip().split(' ', 1)
            if len(s) != 2:
                continue
            oldtags.add(s[1])
        for line in newlines:
            s = line.strip().split(' ', 1)
            if len(s) != 2:
                continue
            if s[1] not in oldtags:
                newtags.add(s[1].strip())

        if not newtags:
            return None, None

        data = "".join(newlines)
        def getfilectx(repo, memctx, f):
            return context.memfilectx(repo, f, data, False, False, None)

        self.ui.status(_("updating tags\n"))
        date = "%s 0" % int(time.mktime(time.gmtime()))
        extra = {'branch': self.tagsbranch}
        ctx = context.memctx(self.repo, (tagparent, None), "update tags",
                             [".hgtags"], getfilectx, "convert-repo", date,
                             extra)
        self.repo.commitctx(ctx)
        return hex(self.repo.changelog.tip()), hex(tagparent)

    def setfilemapmode(self, active):
        self.filemapmode = active

    def putbookmarks(self, updatedbookmark):
        if not len(updatedbookmark):
            return

        self.ui.status(_("updating bookmarks\n"))
        destmarks = self.repo._bookmarks
        for bookmark in updatedbookmark:
            destmarks[bookmark] = bin(updatedbookmark[bookmark])
        destmarks.write()

    def hascommitfrommap(self, rev):
        # the exact semantics of clonebranches is unclear so we can't say no
        return rev in self.repo or self.clonebranches

    def hascommitforsplicemap(self, rev):
        if rev not in self.repo and self.clonebranches:
            raise util.Abort(_('revision %s not found in destination '
                               'repository (lookups with clonebranches=true '
                               'are not implemented)') % rev)
        return rev in self.repo

class mercurial_source(converter_source):
    def __init__(self, ui, path, rev=None):
        converter_source.__init__(self, ui, path, rev)
        self.ignoreerrors = ui.configbool('convert', 'hg.ignoreerrors', False)
        self.ignored = set()
        self.saverev = ui.configbool('convert', 'hg.saverev', False)
        try:
            self.repo = hg.repository(self.ui, path)
            # try to provoke an exception if this isn't really a hg
            # repo, but some other bogus compatible-looking url
            if not self.repo.local():
                raise error.RepoError
        except error.RepoError:
            ui.traceback()
            raise NoRepo(_("%s is not a local Mercurial repository") % path)
        self.lastrev = None
        self.lastctx = None
        self._changescache = None
        self.convertfp = None
        # Restrict converted revisions to startrev descendants
        startnode = ui.config('convert', 'hg.startrev')
        hgrevs = ui.config('convert', 'hg.revs')
        if hgrevs is None:
            if startnode is not None:
                try:
                    startnode = self.repo.lookup(startnode)
                except error.RepoError:
                    raise util.Abort(_('%s is not a valid start revision')
                                     % startnode)
                startrev = self.repo.changelog.rev(startnode)
                children = {startnode: 1}
                for r in self.repo.changelog.descendants([startrev]):
                    children[self.repo.changelog.node(r)] = 1
                self.keep = children.__contains__
            else:
                self.keep = util.always
            if rev:
                self._heads = [self.repo[rev].node()]
            else:
                self._heads = self.repo.heads()
        else:
            if rev or startnode is not None:
                raise util.Abort(_('hg.revs cannot be combined with '
                                   'hg.startrev or --rev'))
            nodes = set()
            parents = set()
            for r in scmutil.revrange(self.repo, [hgrevs]):
                ctx = self.repo[r]
                nodes.add(ctx.node())
                parents.update(p.node() for p in ctx.parents())
            self.keep = nodes.__contains__
            self._heads = nodes - parents

    def changectx(self, rev):
        if self.lastrev != rev:
            self.lastctx = self.repo[rev]
            self.lastrev = rev
        return self.lastctx

    def parents(self, ctx):
        return [p for p in ctx.parents() if p and self.keep(p.node())]

    def getheads(self):
        return [hex(h) for h in self._heads if self.keep(h)]

    def getfile(self, name, rev):
        try:
            fctx = self.changectx(rev)[name]
            return fctx.data(), fctx.flags()
        except error.LookupError:
            return None, None

    def getchanges(self, rev):
        ctx = self.changectx(rev)
        parents = self.parents(ctx)
        if not parents:
            files = sorted(ctx.manifest())
            # getcopies() is not needed for roots, but it is a simple way to
            # detect missing revlogs and abort on errors or populate
            # self.ignored
            self.getcopies(ctx, parents, files)
            return [(f, rev) for f in files if f not in self.ignored], {}
        if self._changescache and self._changescache[0] == rev:
            m, a, r = self._changescache[1]
        else:
            m, a, r = self.repo.status(parents[0].node(), ctx.node())[:3]
        # getcopies() detects missing revlogs early, run it before
        # filtering the changes.
        copies = self.getcopies(ctx, parents, m + a)
        changes = [(name, rev) for name in m + a + r
                   if name not in self.ignored]
        return sorted(changes), copies

    def getcopies(self, ctx, parents, files):
        copies = {}
        for name in files:
            if name in self.ignored:
                continue
            try:
                copysource, _copynode = ctx.filectx(name).renamed()
                if copysource in self.ignored:
                    continue
                # Ignore copy sources not in parent revisions
                found = False
                for p in parents:
                    if copysource in p:
                        found = True
                        break
                if not found:
                    continue
                copies[name] = copysource
            except TypeError:
                pass
            except error.LookupError, e:
                if not self.ignoreerrors:
                    raise
                self.ignored.add(name)
                self.ui.warn(_('ignoring: %s\n') % e)
        return copies

    def getcommit(self, rev):
        ctx = self.changectx(rev)
        parents = [p.hex() for p in self.parents(ctx)]
        if self.saverev:
            crev = rev
        else:
            crev = None
        return commit(author=ctx.user(),
                      date=util.datestr(ctx.date(), '%Y-%m-%d %H:%M:%S %1%2'),
                      desc=ctx.description(), rev=crev, parents=parents,
                      branch=ctx.branch(), extra=ctx.extra(),
                      sortkey=ctx.rev())

    def gettags(self):
        # This will get written to .hgtags, filter non global tags out.
        tags = [t for t in self.repo.tagslist()
                if self.repo.tagtype(t[0]) == 'global']
        return dict([(name, hex(node)) for name, node in tags
                     if self.keep(node)])

    def getchangedfiles(self, rev, i):
        ctx = self.changectx(rev)
        parents = self.parents(ctx)
        if not parents and i is None:
            i = 0
            changes = [], ctx.manifest().keys(), []
        else:
            i = i or 0
            changes = self.repo.status(parents[i].node(), ctx.node())[:3]
        changes = [[f for f in l if f not in self.ignored] for l in changes]

        if i == 0:
            self._changescache = (rev, changes)

        return changes[0] + changes[1] + changes[2]

    def converted(self, rev, destrev):
        if self.convertfp is None:
            self.convertfp = open(self.repo.join('shamap'), 'a')
        self.convertfp.write('%s %s\n' % (destrev, rev))
        self.convertfp.flush()

    def before(self):
        self.ui.debug('run hg source pre-conversion action\n')

    def after(self):
        self.ui.debug('run hg source post-conversion action\n')

    def hasnativeorder(self):
        return True

    def hasnativeclose(self):
        return True

    def lookuprev(self, rev):
        try:
            return hex(self.repo.lookup(rev))
        except error.RepoError:
            return None

    def getbookmarks(self):
        return bookmarks.listbookmarks(self.repo)

    def checkrevformat(self, revstr, mapname='splicemap'):
        """ Mercurial, revision string is a 40 byte hex """
        self.checkhexformat(revstr, mapname)