view mercurial/node.py @ 52164:e01e84e5e426

rust-revlog: add a Rust-only `InnerRevlog`

This mirrors the Python `InnerRevlog` and will be used in a future patch
to replace said Python implementation. This allows us to start doing more
things in pure Rust, in particular reading and writing operations.

A lot of changes have to be introduced all at once, it wouldn't be very
useful to separate this patch IMO since all of them are either interlocked
or only useful with the rest.

# node.py - basic nodeid manipulation for mercurial
#
# Copyright 2005, 2006 Olivia Mackall <[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 annotations

import binascii

# This ugly style has a noticeable effect in manifest parsing
hex = binascii.hexlify
bin = binascii.unhexlify


def short(node):
    return hex(node[:6])


nullrev = -1

# pseudo identifier for working directory
# (experimental, so don't add too many dependencies on it)
wdirrev = 0x7FFFFFFF


class sha1nodeconstants:
    nodelen = 20

    # In hex, this is '0000000000000000000000000000000000000000'
    nullid = b"\0" * nodelen
    nullhex = hex(nullid)

    # Phony node value to stand-in for new files in some uses of
    # manifests.
    # In hex, this is '2121212121212121212121212121212121212121'
    newnodeid = b'!!!!!!!!!!!!!!!!!!!!'
    # In hex, this is '3030303030303030303030303030306164646564'
    addednodeid = b'000000000000000added'
    # In hex, this is '3030303030303030303030306d6f646966696564'
    modifiednodeid = b'000000000000modified'

    wdirfilenodeids = {newnodeid, addednodeid, modifiednodeid}

    # pseudo identifier for working directory
    # (experimental, so don't add too many dependencies on it)
    # In hex, this is 'ffffffffffffffffffffffffffffffffffffffff'
    wdirid = b"\xff" * nodelen
    wdirhex = hex(wdirid)


# legacy starting point for porting modules
nullid = sha1nodeconstants.nullid
nullhex = sha1nodeconstants.nullhex
newnodeid = sha1nodeconstants.newnodeid
addednodeid = sha1nodeconstants.addednodeid
modifiednodeid = sha1nodeconstants.modifiednodeid
wdirfilenodeids = sha1nodeconstants.wdirfilenodeids
wdirid = sha1nodeconstants.wdirid
wdirhex = sha1nodeconstants.wdirhex