comparison mercurial/transaction.py @ 43076:2372284d9457

formatting: blacken the codebase

This is using my patch to black
(https://github.com/psf/black/pull/826) so we don't un-wrap collection
literals.

Done with:

  hg files 'set:**.py - mercurial/thirdparty/** - "contrib/python-zstandard/**"' | xargs black -S

# skip-blame mass-reformatting only

# no-check-commit reformats foo_bar functions

Differential Revision: https://phab.mercurial-scm.org/D6971

43075:57875cf423c9

from . import (
    error,
    pycompat,
    util,
)
from .utils import (
    stringutil,
)

version = 2

# These are the file generators that should only be executed after the
# finalizers are done, since they rely on the output of the finalizers (like
# the changelog having been written).
postfinalizegenerators = {
    'bookmarks',
    'dirstate'
}

gengroupall='all'
gengroupprefinalize='prefinalize'
gengrouppostfinalize='postfinalize'

def active(func):
    def _active(self, *args, **kwds):
        if self._count == 0:
            raise error.Abort(_(
                'cannot use transaction when it is already committed/aborted'))
        return func(self, *args, **kwds)
    return _active

def _playback(journal, report, opener, vfsmap, entries, backupentries,
              unlink=True, checkambigfiles=None):
    for f, o, _ignore in entries:
        if o or not unlink:
            checkambig = checkambigfiles and (f, '') in checkambigfiles
            try:
                fp = opener(f, 'a', checkambig=checkambig)
                if fp.tell() < o:
                    raise error.Abort(_(
                            "attempted to truncate %s to %d bytes, but it was "
                            "already %d bytes\n") % (f, o, fp.tell()))
                fp.truncate(o)
                fp.close()
            except IOError:
                report(_("failed to truncate %s\n") % f)
                raise

                    raise

    backupfiles = []
    for l, f, b, c in backupentries:
        if l not in vfsmap and c:
            report("couldn't handle %s: unknown cache location %s\n"
                        % (b, l))
        vfs = vfsmap[l]
        try:
            if f and b:
                filepath = vfs.join(f)
                backuppath = vfs.join(b)

                opener.unlink(f)
    except (IOError, OSError, error.Abort):
        # only pure backup file remains, it is sage to ignore any error
        pass

class transaction(util.transactional):
    def __init__(self, report, opener, vfsmap, journalname, undoname=None,
                 after=None, createmode=None, validator=None, releasefn=None,
                 checkambigfiles=None, name=r'<unnamed>'):
        """Begin a new transaction

        Begins a new transaction that allows rolling back writes in the event of
        an exception.

        # holds callbacks to call during abort
        self._abortcallback = {}

    def __repr__(self):
        name = r'/'.join(self._names)
        return (r'<transaction name=%s, count=%d, usages=%d>' %
                (name, self._count, self._usages))

    def __del__(self):
        if self._journal:
            self._abort()

        failure and success).
        """
        self._addbackupentry((location, '', tmpfile, False))

    @active
    def addfilegenerator(self, genid, filenames, genfunc, order=0,
                         location=''):
        """add a function to generates some files at transaction commit

        The `genfunc` argument is a function capable of generating proper
        content of each entry in the `filename` tuple.

            order, filenames, genfunc, location = entry

            # for generation at closing, check if it's before or after finalize
            postfinalize = group == gengrouppostfinalize
            if (
                    group != gengroupall
                    and (id in postfinalizegenerators) != postfinalize
            ):
                continue

            vfs = self._vfsmap[location]
            files = []

                        self.registertmp(name, location=location)
                        checkambig = False
                    else:
                        self.addbackup(name, location=location)
                        checkambig = (name, location) in self._checkambigfiles
                    files.append(vfs(name, 'w', atomictemp=True,
                                     checkambig=checkambig))
                genfunc(*files)
                for f in files:
                    f.close()
                # skip discard() loop since we're sure no open file remains
                del files[:]

    @active
    def close(self):
        '''commit the transaction'''
        if self._count == 1:
            self._validator(self)  # will raise exception if needed
            self._validator = None # Help prevent cycles.
            self._generatefiles(group=gengroupprefinalize)
            categories = sorted(self._finalizecallback)
            for cat in categories:
                self._finalizecallback[cat](self)
            # Prevent double usage and help clear cycles.

        self._file.close()
        self._backupsfile.close()
        # cleanup temporary files
        for l, f, b, c in self._backupentries:
            if l not in self._vfsmap and c:
                self._report("couldn't remove %s: unknown cache location %s\n"
                             % (b, l))
                continue
            vfs = self._vfsmap[l]
            if not f and b and vfs.exists(b):
                try:
                    vfs.unlink(b)
                except (IOError, OSError, error.Abort) as inst:
                    if not c:
                        raise
                    # Abort may be raise by read only opener
                    self._report("couldn't remove %s: %s\n"
                                 % (vfs.join(b), inst))
        self._entries = []
        self._writeundo()
        if self._after:
            self._after()
            self._after = None # Help prevent cycles.
        if self._opener.isfile(self._backupjournal):
            self._opener.unlink(self._backupjournal)
        if self._opener.isfile(self._journal):
            self._opener.unlink(self._journal)
        for l, _f, b, c in self._backupentries:
            if l not in self._vfsmap and c:
                self._report("couldn't remove %s: unknown cache location"
                             "%s\n" % (b, l))
                continue
            vfs = self._vfsmap[l]
            if b and vfs.exists(b):
                try:
                    vfs.unlink(b)
                except (IOError, OSError, error.Abort) as inst:
                    if not c:
                        raise
                    # Abort may be raise by read only opener
                    self._report("couldn't remove %s: %s\n"
                                 % (vfs.join(b), inst))
        self._backupentries = []
        self._journal = None

        self._releasefn(self, True) # notify success of closing transaction
        self._releasefn = None # Help prevent cycles.

        # run post close action
        categories = sorted(self._postclosecallback)
        for cat in categories:
            self._postclosecallback[cat](self)

    def _writeundo(self):
        """write transaction data for possible future undo call"""
        if self._undoname is None:
            return
        undobackupfile = self._opener.open("%s.backupfiles" % self._undoname,
                                           'w')
        undobackupfile.write('%d\n' % version)
        for l, f, b, c in self._backupentries:
            if not f:  # temporary file
                continue
            if not b:
                u = ''
            else:
                if l not in self._vfsmap and c:
                    self._report("couldn't remove %s: unknown cache location"
                                 "%s\n" % (b, l))
                    continue
                vfs = self._vfsmap[l]
                base, name = vfs.split(b)
                assert name.startswith(self._journal), name
                uname = name.replace(self._journal, self._undoname, 1)
                u = vfs.reljoin(base, uname)
                util.copyfile(vfs.join(b), vfs.join(u), hardlink=True)
            undobackupfile.write("%s\0%s\0%s\0%d\n" % (l, f, u, c))
        undobackupfile.close()


    def _abort(self):
        self._count = 0
        self._usages = 0
        self._file.close()
        self._backupsfile.close()

            try:
                for cat in sorted(self._abortcallback):
                    self._abortcallback[cat](self)
                # Prevent double usage and help clear cycles.
                self._abortcallback = None
                _playback(self._journal, self._report, self._opener,
                          self._vfsmap, self._entries, self._backupentries,
                          False, checkambigfiles=self._checkambigfiles)
                self._report(_("rollback completed\n"))
            except BaseException as exc:
                self._report(_("rollback failed - please run hg recover\n"))
                self._report(_("(failure reason: %s)\n")
                             % stringutil.forcebytestr(exc))
        finally:
            self._journal = None
            self._releasefn(self, False) # notify failure of transaction
            self._releasefn = None # Help prevent cycles.

def rollback(opener, vfsmap, file, report, checkambigfiles=None):
    """Rolls back the transaction contained in the given file

    Reads the entries in the specified file, and the corresponding

    for l in lines:
        try:
            f, o = l.split('\0')
            entries.append((f, int(o), None))
        except ValueError:
            report(
                _("couldn't read journal entry %r!\n") % pycompat.bytestr(l))

    backupjournal = "%s.backupfiles" % file
    if opener.exists(backupjournal):
        fp = opener.open(backupjournal)
        lines = fp.readlines()

                        # Shave off the trailing newline
                        line = line[:-1]
                        l, f, b, c = line.split('\0')
                        backupentries.append((l, f, b, bool(c)))
            else:
                report(_("journal was created by a different version of "
                         "Mercurial\n"))

    _playback(file, report, opener, vfsmap, entries, backupentries,
              checkambigfiles=checkambigfiles)

43076:2372284d9457

from . import (
    error,
    pycompat,
    util,
)
from .utils import stringutil

version = 2

# These are the file generators that should only be executed after the
# finalizers are done, since they rely on the output of the finalizers (like
# the changelog having been written).
postfinalizegenerators = {'bookmarks', 'dirstate'}

gengroupall = 'all'
gengroupprefinalize = 'prefinalize'
gengrouppostfinalize = 'postfinalize'


def active(func):
    def _active(self, *args, **kwds):
        if self._count == 0:
            raise error.Abort(
                _('cannot use transaction when it is already committed/aborted')
            )
        return func(self, *args, **kwds)

    return _active


def _playback(
    journal,
    report,
    opener,
    vfsmap,
    entries,
    backupentries,
    unlink=True,
    checkambigfiles=None,
):
    for f, o, _ignore in entries:
        if o or not unlink:
            checkambig = checkambigfiles and (f, '') in checkambigfiles
            try:
                fp = opener(f, 'a', checkambig=checkambig)
                if fp.tell() < o:
                    raise error.Abort(
                        _(
                            "attempted to truncate %s to %d bytes, but it was "
                            "already %d bytes\n"
                        )
                        % (f, o, fp.tell())
                    )
                fp.truncate(o)
                fp.close()
            except IOError:
                report(_("failed to truncate %s\n") % f)
                raise

                    raise

    backupfiles = []
    for l, f, b, c in backupentries:
        if l not in vfsmap and c:
            report("couldn't handle %s: unknown cache location %s\n" % (b, l))
        vfs = vfsmap[l]
        try:
            if f and b:
                filepath = vfs.join(f)
                backuppath = vfs.join(b)

                opener.unlink(f)
    except (IOError, OSError, error.Abort):
        # only pure backup file remains, it is sage to ignore any error
        pass


class transaction(util.transactional):
    def __init__(
        self,
        report,
        opener,
        vfsmap,
        journalname,
        undoname=None,
        after=None,
        createmode=None,
        validator=None,
        releasefn=None,
        checkambigfiles=None,
        name=r'<unnamed>',
    ):
        """Begin a new transaction

        Begins a new transaction that allows rolling back writes in the event of
        an exception.

        # holds callbacks to call during abort
        self._abortcallback = {}

    def __repr__(self):
        name = r'/'.join(self._names)
        return r'<transaction name=%s, count=%d, usages=%d>' % (
            name,
            self._count,
            self._usages,
        )

    def __del__(self):
        if self._journal:
            self._abort()

        failure and success).
        """
        self._addbackupentry((location, '', tmpfile, False))

    @active
    def addfilegenerator(self, genid, filenames, genfunc, order=0, location=''):
        """add a function to generates some files at transaction commit

        The `genfunc` argument is a function capable of generating proper
        content of each entry in the `filename` tuple.

            order, filenames, genfunc, location = entry

            # for generation at closing, check if it's before or after finalize
            postfinalize = group == gengrouppostfinalize
            if (
                group != gengroupall
                and (id in postfinalizegenerators) != postfinalize
            ):
                continue

            vfs = self._vfsmap[location]
            files = []

                        self.registertmp(name, location=location)
                        checkambig = False
                    else:
                        self.addbackup(name, location=location)
                        checkambig = (name, location) in self._checkambigfiles
                    files.append(
                        vfs(name, 'w', atomictemp=True, checkambig=checkambig)
                    )
                genfunc(*files)
                for f in files:
                    f.close()
                # skip discard() loop since we're sure no open file remains
                del files[:]

    @active
    def close(self):
        '''commit the transaction'''
        if self._count == 1:
            self._validator(self)  # will raise exception if needed
            self._validator = None  # Help prevent cycles.
            self._generatefiles(group=gengroupprefinalize)
            categories = sorted(self._finalizecallback)
            for cat in categories:
                self._finalizecallback[cat](self)
            # Prevent double usage and help clear cycles.

        self._file.close()
        self._backupsfile.close()
        # cleanup temporary files
        for l, f, b, c in self._backupentries:
            if l not in self._vfsmap and c:
                self._report(
                    "couldn't remove %s: unknown cache location %s\n" % (b, l)
                )
                continue
            vfs = self._vfsmap[l]
            if not f and b and vfs.exists(b):
                try:
                    vfs.unlink(b)
                except (IOError, OSError, error.Abort) as inst:
                    if not c:
                        raise
                    # Abort may be raise by read only opener
                    self._report(
                        "couldn't remove %s: %s\n" % (vfs.join(b), inst)
                    )
        self._entries = []
        self._writeundo()
        if self._after:
            self._after()
            self._after = None  # Help prevent cycles.
        if self._opener.isfile(self._backupjournal):
            self._opener.unlink(self._backupjournal)
        if self._opener.isfile(self._journal):
            self._opener.unlink(self._journal)
        for l, _f, b, c in self._backupentries:
            if l not in self._vfsmap and c:
                self._report(
                    "couldn't remove %s: unknown cache location" "%s\n" % (b, l)
                )
                continue
            vfs = self._vfsmap[l]
            if b and vfs.exists(b):
                try:
                    vfs.unlink(b)
                except (IOError, OSError, error.Abort) as inst:
                    if not c:
                        raise
                    # Abort may be raise by read only opener
                    self._report(
                        "couldn't remove %s: %s\n" % (vfs.join(b), inst)
                    )
        self._backupentries = []
        self._journal = None

        self._releasefn(self, True)  # notify success of closing transaction
        self._releasefn = None  # Help prevent cycles.

        # run post close action
        categories = sorted(self._postclosecallback)
        for cat in categories:
            self._postclosecallback[cat](self)

    def _writeundo(self):
        """write transaction data for possible future undo call"""
        if self._undoname is None:
            return
        undobackupfile = self._opener.open(
            "%s.backupfiles" % self._undoname, 'w'
        )
        undobackupfile.write('%d\n' % version)
        for l, f, b, c in self._backupentries:
            if not f:  # temporary file
                continue
            if not b:
                u = ''
            else:
                if l not in self._vfsmap and c:
                    self._report(
                        "couldn't remove %s: unknown cache location"
                        "%s\n" % (b, l)
                    )
                    continue
                vfs = self._vfsmap[l]
                base, name = vfs.split(b)
                assert name.startswith(self._journal), name
                uname = name.replace(self._journal, self._undoname, 1)
                u = vfs.reljoin(base, uname)
                util.copyfile(vfs.join(b), vfs.join(u), hardlink=True)
            undobackupfile.write("%s\0%s\0%s\0%d\n" % (l, f, u, c))
        undobackupfile.close()

    def _abort(self):
        self._count = 0
        self._usages = 0
        self._file.close()
        self._backupsfile.close()

            try:
                for cat in sorted(self._abortcallback):
                    self._abortcallback[cat](self)
                # Prevent double usage and help clear cycles.
                self._abortcallback = None
                _playback(
                    self._journal,
                    self._report,
                    self._opener,
                    self._vfsmap,
                    self._entries,
                    self._backupentries,
                    False,
                    checkambigfiles=self._checkambigfiles,
                )
                self._report(_("rollback completed\n"))
            except BaseException as exc:
                self._report(_("rollback failed - please run hg recover\n"))
                self._report(
                    _("(failure reason: %s)\n") % stringutil.forcebytestr(exc)
                )
        finally:
            self._journal = None
            self._releasefn(self, False)  # notify failure of transaction
            self._releasefn = None  # Help prevent cycles.


def rollback(opener, vfsmap, file, report, checkambigfiles=None):
    """Rolls back the transaction contained in the given file

    Reads the entries in the specified file, and the corresponding

    for l in lines:
        try:
            f, o = l.split('\0')
            entries.append((f, int(o), None))
        except ValueError:
            report(_("couldn't read journal entry %r!\n") % pycompat.bytestr(l))

    backupjournal = "%s.backupfiles" % file
    if opener.exists(backupjournal):
        fp = opener.open(backupjournal)
        lines = fp.readlines()

                        # Shave off the trailing newline
                        line = line[:-1]
                        l, f, b, c = line.split('\0')
                        backupentries.append((l, f, b, bool(c)))
            else:
                report(
                    _(
                        "journal was created by a different version of "
                        "Mercurial\n"
                    )
                )

    _playback(
        file,
        report,
        opener,
        vfsmap,
        entries,
        backupentries,
        checkambigfiles=checkambigfiles,
    )