view hgext/narrow/narrowtemplates.py @ 42175:cd1bede340b0 stable

setup: tweak error message for Python 3

We now have beta support for Python 3. In my opinion, it isn't
yet stable enough to allow `pip install Mercurial` to work with
Python 3 out of the box: we don't want people accidentally using
Mercurial with Python 3 just yet.

But I do think we should be more friendly about informing people
of their options.

This commit tweaks the error message that users see when running
setup.py with Python 3. We instruct them about the current level
of Python 3 support, point them at the wiki for more info, and
give them instructions on how to bypass the check.

As part of this, I also changed which version value is printed,
as we were printing a named tuple before.

# 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))