contrib/undumprevlog

rev-branch-cache: add a function to generate a part

The function is able to produce a rbc part consumed by the function introduced
into previous changesets. More details on usage and impact in the next
changesets.

#!/usr/bin/env python
# Undump a dump from dumprevlog
# $ hg init
# $ undumprevlog < repo.dump

from __future__ import absolute_import, print_function

import sys
from mercurial import (
    node,
    revlog,
    transaction,
    util,
    vfs as vfsmod,
)

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

opener = vfsmod.vfs('.', False)
tr = transaction.transaction(sys.stderr.write, opener, {'store': opener},
                             "undump.journal")
while True:
    l = sys.stdin.readline()
    if not l:
        break
    if l.startswith("file:"):
        f = l[6:-1]
        r = revlog.revlog(opener, f)
        print(f)
    elif l.startswith("node:"):
        n = node.bin(l[6:-1])
    elif l.startswith("linkrev:"):
        lr = int(l[9:-1])
    elif l.startswith("parents:"):
        p = l[9:-1].split()
        p1 = node.bin(p[0])
        p2 = node.bin(p[1])
    elif l.startswith("length:"):
        length = int(l[8:-1])
        sys.stdin.readline() # start marker
        d = sys.stdin.read(length)
        sys.stdin.readline() # end marker
        r.addrevision(d, tr, lr, p1, p2)

tr.close()