view tests/fakedirstatewritetime.py @ 46874:84a93fa7ecfd

revlog-compression: use zstd by default (if available)

As see in changeset bb271ec2fbfb, zstd is 20% to 50% faster for reading and
writing.

Use take advantage of the new config behavior to try zstd by default, falling
back to zlib is zstd is not available on that plateform.

Differential Revision: https://phab.mercurial-scm.org/D10326

# extension to emulate invoking 'dirstate.write()' at the time
# specified by '[fakedirstatewritetime] fakenow', only when
# 'dirstate.write()' is invoked via functions below:
#
#   - 'workingctx._poststatusfixup()' (= 'repo.status()')
#   - 'committablectx.markcommitted()'

from __future__ import absolute_import

from mercurial import (
    context,
    dirstate,
    extensions,
    policy,
    registrar,
)
from mercurial.utils import dateutil

try:
    from mercurial import rustext

    rustext.__name__  # force actual import (see hgdemandimport)
except ImportError:
    rustext = None

configtable = {}
configitem = registrar.configitem(configtable)

configitem(
    b'fakedirstatewritetime',
    b'fakenow',
    default=None,
)

parsers = policy.importmod('parsers')
rustmod = policy.importrust('parsers')


def pack_dirstate(fakenow, orig, dmap, copymap, pl, now):
    # execute what original parsers.pack_dirstate should do actually
    # for consistency
    actualnow = int(now)
    for f, e in dmap.items():
        if e[0] == 'n' and e[3] == actualnow:
            e = parsers.dirstatetuple(e[0], e[1], e[2], -1)
            dmap[f] = e

    return orig(dmap, copymap, pl, fakenow)


def fakewrite(ui, func):
    # fake "now" of 'pack_dirstate' only if it is invoked while 'func'

    fakenow = ui.config(b'fakedirstatewritetime', b'fakenow')
    if not fakenow:
        # Execute original one, if fakenow isn't configured. This is
        # useful to prevent subrepos from executing replaced one,
        # because replacing 'parsers.pack_dirstate' is also effective
        # in subrepos.
        return func()

    # parsing 'fakenow' in YYYYmmddHHMM format makes comparison between
    # 'fakenow' value and 'touch -t YYYYmmddHHMM' argument easy
    fakenow = dateutil.parsedate(fakenow, [b'%Y%m%d%H%M'])[0]

    if rustmod is not None:
        # The Rust implementation does not use public parse/pack dirstate
        # to prevent conversion round-trips
        orig_dirstatemap_write = dirstate.dirstatemap.write
        wrapper = lambda self, st, now: orig_dirstatemap_write(
            self, st, fakenow
        )
        dirstate.dirstatemap.write = wrapper

    orig_dirstate_getfsnow = dirstate._getfsnow
    wrapper = lambda *args: pack_dirstate(fakenow, orig_pack_dirstate, *args)

    orig_module = parsers
    orig_pack_dirstate = parsers.pack_dirstate

    orig_module.pack_dirstate = wrapper
    dirstate._getfsnow = lambda *args: fakenow
    try:
        return func()
    finally:
        orig_module.pack_dirstate = orig_pack_dirstate
        dirstate._getfsnow = orig_dirstate_getfsnow
        if rustmod is not None:
            dirstate.dirstatemap.write = orig_dirstatemap_write


def _poststatusfixup(orig, workingctx, status, fixup):
    ui = workingctx.repo().ui
    return fakewrite(ui, lambda: orig(workingctx, status, fixup))


def markcommitted(orig, committablectx, node):
    ui = committablectx.repo().ui
    return fakewrite(ui, lambda: orig(committablectx, node))


def extsetup(ui):
    extensions.wrapfunction(
        context.workingctx, '_poststatusfixup', _poststatusfixup
    )
    extensions.wrapfunction(context.workingctx, 'markcommitted', markcommitted)