tests/testlib/ext-sidedata.py

node: import symbols explicitly

There is no point in lazy importing mercurial.node, it is used all over
the place anyway. So consistently import the used symbols directly.
Fix one file using symbols indirectly via mercurial.revlog.

Differential Revision: https://phab.mercurial-scm.org/D9480

# ext-sidedata.py - small extension to test the sidedata logic
#
# Copyright 2019 Pierre-Yves David <[e-mail])
#
# This software may be used and distributed according to the terms of the
# GNU General Public License version 2 or any later version.

from __future__ import absolute_import

import hashlib
import struct

from mercurial.node import (
    nullid,
    nullrev,
)
from mercurial import (
    extensions,
    requirements,
    revlog,
)

from mercurial.upgrade_utils import engine as upgrade_engine

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 wraprevision(orig, self, nodeorrev, *args, **kwargs):
    text = orig(self, nodeorrev, *args, **kwargs)
    if getattr(self, 'sidedatanocheck', False):
        return text
    if nodeorrev != nullrev and nodeorrev != nullid:
        sd = self.sidedata(nodeorrev)
        if len(text) != struct.unpack('>I', sd[sidedata.SD_TEST1])[0]:
            raise RuntimeError('text size mismatch')
        expected = sd[sidedata.SD_TEST2]
        got = hashlib.sha256(text).digest()
        if got != expected:
            raise RuntimeError('sha256 mismatch')
    return text


def wrapgetsidedatacompanion(orig, srcrepo, dstrepo):
    sidedatacompanion = orig(srcrepo, dstrepo)
    addedreqs = dstrepo.requirements - srcrepo.requirements
    if requirements.SIDEDATA_REQUIREMENT in addedreqs:
        assert sidedatacompanion is None  # deal with composition later

        def sidedatacompanion(revlog, rev):
            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 False, (), update, 0, 0

    return sidedatacompanion


def extsetup(ui):
    extensions.wrapfunction(revlog.revlog, 'addrevision', wrapaddrevision)
    extensions.wrapfunction(revlog.revlog, 'revision', wraprevision)
    extensions.wrapfunction(
        upgrade_engine, 'getsidedatacompanion', wrapgetsidedatacompanion
    )