view mercurial/rcutil.py @ 32476:e5e31b0fc924

hidden: use _domainancestors to compute revs revealed by dynamic blocker

The complexity of computing the revealed changesets is now 'O(revealed)'.
This massively speeds up the computation on large repository. Moving it to the
millisecond range.

Below are timing from two Mozilla repositories with different contents:

1) mozilla repository with:
 * 400667 changesets
 * 35 hidden changesets (first rev-268334)
 * 288 visible drafts
 * obsolete working copy (dynamicblockers),

Before:
! visible
! wall 0.030247 comb 0.030000 user 0.030000 sys 0.000000 (best of 100)

After:
! visible
! wall 0.000585 comb 0.000000 user 0.000000 sys 0.000000 (best of 4221)

The timing above include the computation of obsolete changeset:
! obsolete
! wall 0.000396 comb 0.000000 user 0.000000 sys 0.000000 (best of 6816)

So adjusted time give 30ms before versus 0.2ms after. A 150x speedup.

2) mozilla repository with:
 * 405645 changesets
 * 4312 hidden changesets (first rev-326004)
 * 264 visible drafts
 * obsolete working copy (dynamicblockers),

Before:
! visible
! wall 0.168658 comb 0.170000 user 0.170000 sys 0.000000 (best of 48)

After
! visible
! wall 0.008612 comb 0.010000 user 0.010000 sys 0.000000 (best of 325)

The timing above include the computation of obsolete changeset:
! obsolete
! wall 0.006408 comb 0.010000 user 0.010000 sys 0.000000 (best of 404)

So adjusted time give 160ms before versus 2ms after. A 75x speedup.

# 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.osname == 'nt':
    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'}