mercurial/node.py

keepalive: reorder header precedence

There are 3 sources of headers used by this function:

* The default headers defined by the URL opener
* Headers that are copied on redirects
* Headers that aren't copied on redirects

Previously, we applied the default headers from the URL
opener last. This feels wrong to me as those headers are
the most low level and something built on top of the URL
opener may wish to override them. So, this commit changes
the order to apply them with the least precedence.

While I was here, I removed a Python version test that is
no longer necessary.

# 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.

from __future__ import absolute_import

import binascii

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

nullrev = -1
nullid = b"\0" * 20
nullhex = hex(nullid)

# Phony node value to stand-in for new files in some uses of
# manifests.
newnodeid = '!' * 20
addednodeid = ('0' * 15) + 'added'
modifiednodeid = ('0' * 12) + 'modified'

wdirnodes = set((newnodeid, addednodeid, modifiednodeid))

# pseudo identifiers for working directory
# (they are experimental, so don't add too many dependencies on them)
wdirrev = 0x7fffffff
wdirid = b"\xff" * 20

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