view mercurial/rcutil.py @ 44763:94f4f2ec7dee stable

packaging: support building Inno installer with PyOxidizer

We want to start distributing Mercurial on Python 3 on
Windows. PyOxidizer will be our vehicle for achieving that.

This commit implements basic support for producing Inno
installers using PyOxidizer.

While it is an eventual goal of PyOxidizer to produce
installers, those features aren't yet implemented. So our
strategy for producing Mercurial installers is similar to
what we've been doing with py2exe: invoke a build system to
produce files then stage those files into a directory so they
can be turned into an installer.

We had to make significant alterations to the pyoxidizer.bzl
config file to get it to produce the files that we desire for
a Windows install. This meant differentiating the build targets
so we can target Windows specifically.

We've added a new module to hgpackaging to deal with interacting
with PyOxidizer. It is similar to pyexe: we invoke a build process
then copy files to a staging directory. Ideally these extra
files would be defined in pyoxidizer.bzl. But I don't think it
is worth doing at this time, as PyOxidizer's config files are
lacking some features to make this turnkey.

The rest of the change is introducing a variant of the
Inno installer code that invokes PyOxidizer instead of
py2exe.

Comparing the Python 2.7 based Inno installers with this
one, the following changes were observed:

* No lib/*.{pyd, dll} files
* No Microsoft.VC90.CRT.manifest
* No msvc{m,p,r}90.dll files
* python27.dll replaced with python37.dll
* Add vcruntime140.dll file

The disappearance of the .pyd and .dll files is acceptable, as
PyOxidizer has embedded these in hg.exe and loads them from
memory.

The disappearance of the *90* files is acceptable because those
provide the Visual C++ 9 runtime, as required by Python 2.7.
Similarly, the appearance of vcruntime140.dll is a requirement
of Python 3.7.

Differential Revision: https://phab.mercurial-scm.org/D8473

# 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,
)

from .utils import resourceutil

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 sorted(
            join(p, f) for f, k in util.listdir(p) if f.endswith(b'.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 = [
        (b'EDITOR', b'ui', b'editor'),
        (b'VISUAL', b'ui', b'editor'),
        (b'PAGER', b'pager', b'pager'),
    ]
    result = []
    for envname, section, configname in checklist:
        if envname not in env:
            continue
        result.append((section, configname, env[envname], b'$%s' % envname))
    return result


def default_rc_resources():
    """return rc resource IDs in defaultrc"""
    rsrcs = resourceutil.contents(b'mercurial.defaultrc')
    return [
        (b'mercurial.defaultrc', r)
        for r in sorted(rsrcs)
        if resourceutil.is_resource(b'mercurial.defaultrc', r)
        and r.endswith(b'.rc')
    ]


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', 'items' or 'resource'. 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.
    If type is 'resource', obj is a tuple of (package name, resource name).
    '''
    envrc = (b'items', envrcitems())

    if b'HGRCPATH' in encoding.environ:
        # assume HGRCPATH is all about user configs so environments can be
        # overridden.
        _rccomponents = [envrc]
        for p in encoding.environ[b'HGRCPATH'].split(pycompat.ospathsep):
            if not p:
                continue
            _rccomponents.extend((b'path', p) for p in _expandrcpath(p))
    else:
        _rccomponents = [(b'resource', r) for r in default_rc_resources()]

        normpaths = lambda paths: [
            (b'path', os.path.normpath(p)) for p in paths
        ]
        _rccomponents.extend(normpaths(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 {b'LESS': b'FRX', b'LV': b'-c'}


def use_repo_hgrc():
    """True if repositories `.hg/hgrc` config should be read"""
    return b'HGRCSKIPREPO' not in encoding.environ