view mercurial/node.py @ 14451:c78d41db6f88

patch: refactor file creation/removal detection

The patcher has to know if a file is being created or removed to check if the
target already exists, or to actually unlink the file when a hunk emptying it
is applied. This was done by embedding the creation/removal information in the
first (and only) hunk attached to the file.

There are two problems with this approach:

- creation/removal is really a property of the file being patched and not its
  hunk.

- for regular patches, file creation cannot be deduced at parsing time: there
  are case where the *stripped* file paths must be compared. Modifying hunks
  after their creation is clumsy and prevent further refactorings related to
  copies handling.

Instead, we delegate this job to selectfile() which has all the relevant
information, and remove the hunk createfile() and rmfile() methods.

# node.py - basic nodeid manipulation for mercurial
#
# Copyright 2005, 2006 Matt 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.

import binascii

nullrev = -1
nullid = "\0" * 20

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

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