contrib/dumprevlog

copies: stop attempt to avoid extra dict copies around branching

In the python code, we attempt to avoid unnecessary dict copies when gathering
copy information. However that logic is wobbly and I keep running into case
where independent branches affects each others.

With the current code we can't ensure we are the only "user" of dict when
dealing with merge.

This caused havoc in the next series on tests I am about to introduce.

So for now I am disabling the faulty optimisation. I believe we will need a
dedicated overlay to deal with the "copy on write logic" to have something
correct. I am also hoping to find time to build dedicated test case for this
category of problem instead of relying on side effect in other tests. However
for now I am focussing on another issue.

Differential Revision: https://phab.mercurial-scm.org/D9608

#!/usr/bin/env python3
# Dump revlogs as raw data stream
# $ find .hg/store/ -name "*.i" | xargs dumprevlog > repo.dump

from __future__ import absolute_import, print_function

import sys
from mercurial.node import hex
from mercurial import (
    encoding,
    pycompat,
    revlog,
)
from mercurial.utils import procutil

for fp in (sys.stdin, sys.stdout, sys.stderr):
    procutil.setbinary(fp)


def binopen(path, mode=b'rb'):
    if b'b' not in mode:
        mode = mode + b'b'
    return open(path, pycompat.sysstr(mode))


binopen.options = {}


def printb(data, end=b'\n'):
    sys.stdout.flush()
    procutil.stdout.write(data + end)


for f in sys.argv[1:]:
    r = revlog.revlog(binopen, encoding.strtolocal(f))
    print("file:", f)
    for i in r:
        n = r.node(i)
        p = r.parents(n)
        d = r.revision(n)
        printb(b"node: %s" % hex(n))
        printb(b"linkrev: %d" % r.linkrev(i))
        printb(b"parents: %s %s" % (hex(p[0]), hex(p[1])))
        printb(b"length: %d" % len(d))
        printb(b"-start-")
        printb(d)
        printb(b"-end-")