view mercurial/rcutil.py @ 34852:d45236f3d38e

log: add obsfate by default in changeset printer

Having an obsfate by default in log will be useful for users to understand why
they have obsolete and unstable changesets. Obsfate will only be shown for
obsolete changesets, which only happens if people opt-in to experimental feature.

But when obsolete changeset are visible, it is very useful to understand where
they are. Having it in log could be sufficient for most people, so they don't
have to learn a new command (like obslog which is itself useful in case of
divergences).

For example, when pulling and working directory parent become obsolete:

  $ hg pull
  ...
  working directory parent is obsolete! (f936c1697205)

This message comes from the Evolve extension.

Obsfate would comes handy:

  $ hg log -G
  o  changeset:   2:6f91013c5136
  |  tag:         tip
  |  parent:      0:4ef7b558f3ec
  |  user:        Boris Feld <[e-mail]>
  |  date:        Mon Oct 09 16:00:27 2017 +0200
  |  summary:     A
  |
  | @  changeset:   1:f936c1697205
  |/   user:        Boris Feld <[e-mail]>
  |    date:        Mon Oct 09 16:00:27 2017 +0200
  |    obsfate:     rewritten using amend as 2:6f91013c5136
  |    summary:     -A
  |
  o  changeset:   0:feb4dd822b8c
     user:        Boris Feld <[e-mail]>
     date:        Tue Oct 09 16:00:00 2017 +0200
     summary:     ROOT

And once we update, we don't have an obsolete changeset in the log anymore so
we don't show obsfate anymore, most users won't see obsfate often if they
don't have obsolete changeset often:

  @  changeset:   2:6f91013c5136
  |  tag:         tip
  |  parent:      0:4ef7b558f3ec
  |  user:        Boris Feld <[e-mail]>
  |  date:        Mon Oct 09 16:00:27 2017 +0200
  |  summary:     A
  |
  o  changeset:   0:feb4dd822b8c
     user:        Boris Feld <[e-mail]>
     date:        Tue Oct 09 16:00:00 2017 +0200
     summary:     ROOT

# rcutil.py - utilities about config paths, special config sections etc.
#
#  Copyright Mercurial Contributors
#
# 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

from . import (
    encoding,
    pycompat,
    util,
)

if pycompat.iswindows:
    from . import scmwindows as scmplatform
else:
    from . import scmposix as scmplatform

fallbackpager = scmplatform.fallbackpager
systemrcpath = scmplatform.systemrcpath
userrcpath = scmplatform.userrcpath

def _expandrcpath(path):
    '''path could be a file or a directory. return a list of file paths'''
    p = util.expandpath(path)
    if os.path.isdir(p):
        join = os.path.join
        return [join(p, f) for f, k in util.listdir(p) if f.endswith('.rc')]
    return [p]

def envrcitems(env=None):
    '''Return [(section, name, value, source)] config items.

    The config items are extracted from environment variables specified by env,
    used to override systemrc, but not userrc.

    If env is not provided, encoding.environ will be used.
    '''
    if env is None:
        env = encoding.environ
    checklist = [
        ('EDITOR', 'ui', 'editor'),
        ('VISUAL', 'ui', 'editor'),
        ('PAGER', 'pager', 'pager'),
    ]
    result = []
    for envname, section, configname in checklist:
        if envname not in env:
            continue
        result.append((section, configname, env[envname], '$%s' % envname))
    return result

def defaultrcpath():
    '''return rc paths in default.d'''
    path = []
    defaultpath = os.path.join(util.datapath, 'default.d')
    if os.path.isdir(defaultpath):
        path = _expandrcpath(defaultpath)
    return path

def rccomponents():
    '''return an ordered [(type, obj)] about where to load configs.

    respect $HGRCPATH. if $HGRCPATH is empty, only .hg/hgrc of current repo is
    used. if $HGRCPATH is not set, the platform default will be used.

    if a directory is provided, *.rc files under it will be used.

    type could be either 'path' or 'items', if type is 'path', obj is a string,
    and is the config file path. if type is 'items', obj is a list of (section,
    name, value, source) that should fill the config directly.
    '''
    envrc = ('items', envrcitems())

    if 'HGRCPATH' in encoding.environ:
        # assume HGRCPATH is all about user configs so environments can be
        # overridden.
        _rccomponents = [envrc]
        for p in encoding.environ['HGRCPATH'].split(pycompat.ospathsep):
            if not p:
                continue
            _rccomponents.extend(('path', p) for p in _expandrcpath(p))
    else:
        normpaths = lambda paths: [('path', os.path.normpath(p)) for p in paths]
        _rccomponents = normpaths(defaultrcpath() + systemrcpath())
        _rccomponents.append(envrc)
        _rccomponents.extend(normpaths(userrcpath()))
    return _rccomponents

def defaultpagerenv():
    '''return a dict of default environment variables and their values,
    intended to be set before starting a pager.
    '''
    return {'LESS': 'FRX', 'LV': '-c'}