hg

notify: don't produce errors if a revision is not found

Notify extension has a way to only subscribe to a specific revset, such as
"branch(foo)". Before this patch, when there was no branch with that name, it
would produce a traceback saying "unknown revision: foo". With this patch it
would no longer do that, and instead it'll assume there are no revisions that
match this revset. I think this patch is an improvement in general, but there's
a reason I'm sending it now.

test-notify.t has a test case where it obsoletes the only revision on a branch,
and previously that wouldn't produce any complications, because head
computation wasn't obsolescence-aware. Now if the only revision on a branch is
obsolete, repo should not see that branch at all.

That branch will still be present in branchcache (with an empty list of
revisions) until the next patch.

Differential Revision: https://phab.mercurial-scm.org/D12134

#!/usr/bin/env python3
#
# mercurial - scalable distributed SCM
#
# Copyright 2005-2007 Olivia 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 os
import sys

libdir = '@LIBDIR@'

if libdir != '@' 'LIBDIR' '@':
    if not os.path.isabs(libdir):
        libdir = os.path.join(
            os.path.dirname(os.path.realpath(__file__)), libdir
        )
        libdir = os.path.abspath(libdir)
    sys.path.insert(0, libdir)

# Make `pip install --user ...` packages available to the official Windows
# build.  Most py2 packaging installs directly into the system python
# environment, so no changes are necessary for other platforms.  The Windows
# py2 package uses py2exe, which lacks a `site` module.  Hardcode it according
# to the documentation.
if getattr(sys, 'frozen', None) == 'console_exe':
    vi = sys.version_info
    appdata = os.environ.get('APPDATA')
    if appdata:
        sys.path.append(
            os.path.join(
                appdata,
                'Python',
                'Python%d%d' % (vi[0], vi[1]),
                'site-packages',
            )
        )

from hgdemandimport import tracing

with tracing.log('hg script'):
    # enable importing on demand to reduce startup time
    try:
        if sys.version_info[0] < 3 or sys.version_info >= (3, 6):
            import hgdemandimport

            hgdemandimport.enable()
    except ImportError:
        sys.stderr.write(
            "abort: couldn't find mercurial libraries in [%s]\n"
            % ' '.join(sys.path)
        )
        sys.stderr.write("(check your install and PYTHONPATH)\n")
        sys.exit(-1)

    from mercurial import dispatch

    dispatch.run()