extdiff: add a --patch argument for diffing changeset deltas
One of the things I missed the most when transitioning from versioned MQ to
evolve was the loss of being able to check that rebase conflicts were properly
resolved by:
$ hg ci --mq -m "before"
$ hg rebase -s qbase -d tip
$ hg bcompare --mq
The old csets stay in the tree with evolve, but a straight diff includes all of
the other changes that were pulled in, obscuring the code that was rebased.
Diffing deltas can be confusing, but unless radical changes were made during the
resolve, it is very clear when individual hunks are added, dropped or modified.
Unlike the MQ technique, this can only compare a single pair of csets/patches at
a time. Like the MQ method, this also highlights changes in the commit comment
and other metadata.
I originally tried monkey patching from the evolve extension, but that is too
complicated given that it depends on the order the two different extensions are
loaded. This functionality is also useful when comparing grafts however, so
implementing it in the core is more than just convenience.
The --change argument doesn't make much sense for this, but it isn't harmful so
I didn't bother blocking it. The -I/-X options are ignored because of a
limitation of cmdutil.export(). We'll fix that next.
# peer.py - repository base classes for mercurial
#
# Copyright 2005, 2006 Matt Mackall <mpm@selenic.com>
# Copyright 2006 Vadim Gelfer <vadim.gelfer@gmail.com>
#
# 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
from .i18n import _
from . import (
error,
util,
)
# abstract batching support
class future(object):
'''placeholder for a value to be set later'''
def set(self, value):
if util.safehasattr(self, 'value'):
raise error.RepoError("future is already set")
self.value = value
class batcher(object):
'''base class for batches of commands submittable in a single request
All methods invoked on instances of this class are simply queued and
return a a future for the result. Once you call submit(), all the queued
calls are performed and the results set in their respective futures.
'''
def __init__(self):
self.calls = []
def __getattr__(self, name):
def call(*args, **opts):
resref = future()
self.calls.append((name, args, opts, resref,))
return resref
return call
def submit(self):
pass
class localbatch(batcher):
'''performs the queued calls directly'''
def __init__(self, local):
batcher.__init__(self)
self.local = local
def submit(self):
for name, args, opts, resref in self.calls:
resref.set(getattr(self.local, name)(*args, **opts))
def batchable(f):
'''annotation for batchable methods
Such methods must implement a coroutine as follows:
@batchable
def sample(self, one, two=None):
# Handle locally computable results first:
if not one:
yield "a local result", None
# Build list of encoded arguments suitable for your wire protocol:
encargs = [('one', encode(one),), ('two', encode(two),)]
# Create future for injection of encoded result:
encresref = future()
# Return encoded arguments and future:
yield encargs, encresref
# Assuming the future to be filled with the result from the batched
# request now. Decode it:
yield decode(encresref.value)
The decorator returns a function which wraps this coroutine as a plain
method, but adds the original method as an attribute called "batchable",
which is used by remotebatch to split the call into separate encoding and
decoding phases.
'''
def plain(*args, **opts):
batchable = f(*args, **opts)
encargsorres, encresref = batchable.next()
if not encresref:
return encargsorres # a local result in this case
self = args[0]
encresref.set(self._submitone(f.func_name, encargsorres))
return batchable.next()
setattr(plain, 'batchable', f)
return plain
class peerrepository(object):
def batch(self):
return localbatch(self)
def capable(self, name):
'''tell whether repo supports named capability.
return False if not supported.
if boolean capability, return True.
if string capability, return string.'''
caps = self._capabilities()
if name in caps:
return True
name_eq = name + '='
for cap in caps:
if cap.startswith(name_eq):
return cap[len(name_eq):]
return False
def requirecap(self, name, purpose):
'''raise an exception if the given capability is not present'''
if not self.capable(name):
raise error.CapabilityError(
_('cannot %s; remote repository does not '
'support the %r capability') % (purpose, name))
def local(self):
'''return peer as a localrepo, or None'''
return None
def peer(self):
return self
def canpush(self):
return True
def close(self):
pass