interfaces: introduce and use a protocol class for the `mpatch` module
See
f2832de2a46c for details when this was done for the `bdiff` module.
Two things worth pointing out-
1) The `cffi` module "inherits" the `pure` implementation of `patchedsize()`
because of its wildcard import.
2) It's odd that the `mpatchError` lives in both `pure` and `cext` modules.
I initially thought to move the exception into the new class, and make the
existing class name an alias to the class in the new location, but the exception
is created in C code by the `cext` module, so that won't work. I don't think a
protocol class is approriate, because there's nothing special about the class to
distinguish from any other `Exception`. Fortunately, nobody is catching this
exception in core, so we can kick the can down the road.
# ext-sidedata.py - small extension to test the sidedata logic
#
# Copyright 2019 Pierre-Yves David <pierre-yves.david@octobus.net>
#
# This software may be used and distributed according to the terms of the
# GNU General Public License version 2 or any later version.
import hashlib
import struct
from mercurial.node import nullrev
from mercurial import (
extensions,
requirements,
revlog,
)
from mercurial.upgrade_utils import engine as upgrade_engine
from mercurial.revlogutils import constants
from mercurial.revlogutils import sidedata
def wrapaddrevision(
orig, self, text, transaction, link, p1, p2, *args, **kwargs
):
if kwargs.get('sidedata') is None:
kwargs['sidedata'] = {}
sd = kwargs['sidedata']
## let's store some arbitrary data just for testing
# text length
sd[sidedata.SD_TEST1] = struct.pack('>I', len(text))
# and sha2 hashes
sha256 = hashlib.sha256(text).digest()
sd[sidedata.SD_TEST2] = struct.pack('>32s', sha256)
return orig(self, text, transaction, link, p1, p2, *args, **kwargs)
def wrap_revisiondata(orig, self, nodeorrev, *args, **kwargs):
text = orig(self, nodeorrev, *args, **kwargs)
sd = self.sidedata(nodeorrev)
if getattr(self, 'sidedatanocheck', False):
return text
if self.feature_config.has_side_data:
return text
if nodeorrev != nullrev and nodeorrev != self.nullid:
cat1 = sd.get(sidedata.SD_TEST1)
if cat1 is not None and len(text) != struct.unpack('>I', cat1)[0]:
raise RuntimeError('text size mismatch')
expected = sd.get(sidedata.SD_TEST2)
got = hashlib.sha256(text).digest()
if expected is not None and got != expected:
raise RuntimeError('sha256 mismatch')
return text
def wrapget_sidedata_helpers(orig, srcrepo, dstrepo):
repo, computers, removers = orig(srcrepo, dstrepo)
assert not computers and not removers # deal with composition later
addedreqs = dstrepo.requirements - srcrepo.requirements
if requirements.REVLOGV2_REQUIREMENT in addedreqs:
def computer(repo, revlog, rev, old_sidedata):
assert not old_sidedata # not supported yet
update = {}
revlog.sidedatanocheck = True
try:
text = revlog.revision(rev)
finally:
del revlog.sidedatanocheck
## let's store some arbitrary data just for testing
# text length
update[sidedata.SD_TEST1] = struct.pack('>I', len(text))
# and sha2 hashes
sha256 = hashlib.sha256(text).digest()
update[sidedata.SD_TEST2] = struct.pack('>32s', sha256)
return update, (0, 0)
srcrepo.register_sidedata_computer(
constants.KIND_CHANGELOG,
b"whatever",
(sidedata.SD_TEST1, sidedata.SD_TEST2),
computer,
0,
)
dstrepo.register_wanted_sidedata(b"whatever")
return sidedata.get_sidedata_helpers(srcrepo, dstrepo._wanted_sidedata)
def extsetup(ui):
extensions.wrapfunction(revlog.revlog, 'addrevision', wrapaddrevision)
extensions.wrapfunction(revlog.revlog, '_revisiondata', wrap_revisiondata)
extensions.wrapfunction(
upgrade_engine, 'get_sidedata_helpers', wrapget_sidedata_helpers
)
def reposetup(ui, repo):
# We don't register sidedata computers because we don't care within these
# tests
repo.register_wanted_sidedata(sidedata.SD_TEST1)
repo.register_wanted_sidedata(sidedata.SD_TEST2)