contrib/dumprevlog

obsolescence: add test for the "branch replacement" logic during push, case D6

Mercurial checks for the introduction of new heads on push. Evolution comes
into play to detect if existing branches on the server are being replaced by
some of the new one we push.

The current code for this logic is very basic (eg: issue4354) and was poorly
tested. We have a better implementation coming in the evolve extension fixing
these issues and with more serious tests coverage. In the process of upstreaming
this improved logic, we start with adding the test case that are already passing
with the current implementation. Once they are all in, we'll upstream the better
implementation and the extra test cases.

See inline documentation for details about the test case added in this
changeset.

#!/usr/bin/env python
# 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 import (
    node,
    revlog,
    util,
)

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

for f in sys.argv[1:]:
    binopen = lambda fn: open(fn, 'rb')
    r = revlog.revlog(binopen, f)
    print("file:", f)
    for i in r:
        n = r.node(i)
        p = r.parents(n)
        d = r.revision(n)
        print("node:", node.hex(n))
        print("linkrev:", r.linkrev(i))
        print("parents:", node.hex(p[0]), node.hex(p[1]))
        print("length:", len(d))
        print("-start-")
        print(d)
        print("-end-")