tests/fakepatchtime.py

exchangev2: use filesdata

filesdata is a more efficient mechanism for bulk fetching files data for a
range of changesets. Let's use it in exchangev2.

With this change, a client performing a full clone of mozilla-unified
transmits substantially fewer bytes across the wire:

before: 139,124,863 bytes sent
after:   20,522,499 bytes sent

The bulk of the remaining bytes is likely the transfer of ~1M nodes for
changesets and manifests. We can eliminate this by making requests in
terms of node ranges instead of explicit node lists...

Differential Revision: https://phab.mercurial-scm.org/D4982

# extension to emulate invoking 'patch.internalpatch()' at the time
# specified by '[fakepatchtime] fakenow'

from __future__ import absolute_import

from mercurial import (
    extensions,
    patch as patchmod,
    registrar,
)
from mercurial.utils import dateutil

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

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

def internalpatch(orig, ui, repo, patchobj, strip,
                  prefix=b'', files=None,
                  eolmode=b'strict', similarity=0):
    if files is None:
        files = set()
    r = orig(ui, repo, patchobj, strip,
             prefix=prefix, files=files,
             eolmode=eolmode, similarity=similarity)

    fakenow = ui.config(b'fakepatchtime', b'fakenow')
    if fakenow:
        # 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]
        for f in files:
            repo.wvfs.utime(f, (fakenow, fakenow))

    return r

def extsetup(ui):
    extensions.wrapfunction(patchmod, 'internalpatch', internalpatch)