view hgext/narrow/narrowtemplates.py @ 40589:054d0fcba2c4

commandserver: add experimental option to use separate message channel

This is loosely based on the idea of the TortoiseHg's pipeui extension,
which attaches ui.label to message text so the command-server client can
capture prompt text, for example.

https://bitbucket.org/tortoisehg/thg/src/4.7.2/tortoisehg/util/pipeui.py

I was thinking that this functionality could be generalized to templating,
but changed mind as doing template stuff would be unnecessarily complex.
It's merely a status message, a simple serialization option should suffice.

Since this slightly changes the command-server protocol, it's gated by a
config knob. If the config is enabled, and if it's supported by the server,
"message-encoding: <name>" is advertised so the client can stop parsing
'o'/'e' channel data and read encoded messages from the 'm' channel. As we
might add new message encodings in future releases, client can specify a list
of encoding names in preferred order.

This patch includes 'cbor' encoding as example. Perhaps, 'json' should be
supported as well.

# narrowtemplates.py - added template keywords for narrow clones
#
# Copyright 2017 Google, Inc.
#
# 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 mercurial import (
    registrar,
    revlog,
)

keywords = {}
templatekeyword = registrar.templatekeyword(keywords)
revsetpredicate = registrar.revsetpredicate()

def _isellipsis(repo, rev):
    if repo.changelog.flags(rev) & revlog.REVIDX_ELLIPSIS:
        return True
    return False

@templatekeyword('ellipsis', requires={'repo', 'ctx'})
def ellipsis(context, mapping):
    """String. 'ellipsis' if the change is an ellipsis node, else ''."""
    repo = context.resource(mapping, 'repo')
    ctx = context.resource(mapping, 'ctx')
    if _isellipsis(repo, ctx.rev()):
        return 'ellipsis'
    return ''

@templatekeyword('outsidenarrow', requires={'repo', 'ctx'})
def outsidenarrow(context, mapping):
    """String. 'outsidenarrow' if the change affects no tracked files,
    else ''."""
    repo = context.resource(mapping, 'repo')
    ctx = context.resource(mapping, 'ctx')
    m = repo.narrowmatch()
    if not m.always():
        if not any(m(f) for f in ctx.files()):
            return 'outsidenarrow'
    return ''

@revsetpredicate('ellipsis()')
def ellipsisrevset(repo, subset, x):
    """Changesets that are ellipsis nodes."""
    return subset.filter(lambda r: _isellipsis(repo, r))