Re: [gentoo-dev] Locale check in python_pkg_setup()

[Alec Warner <antarus@gentoo.org>]

On Sat, Jul 31, 2010 at 7:44 AM, Arfrever Frehtes Taifersar Arahesis
<Arfrever@gentoo.org> wrote:
> 2010-07-30 04:36:22 Brian Harring napisał(a):
>> On Fri, Jul 30, 2010 at 01:16:42AM +0200, Arfrever Frehtes Taifersar Arahesis wrote:
>> > --- python.eclass
>> > +++ python.eclass
>> > @@ -355,6 +355,8 @@
>> >     # Check if phase is pkg_setup().
>> >     [[ "${EBUILD_PHASE}" != "setup" ]] && die "${FUNCNAME}() can be used only in pkg_setup() phase"
>> >
>> > +   local locale
>> > +
>> >     if [[ "$#" -ne 0 ]]; then
>> >             die "${FUNCNAME}() does not accept arguments"
>> >     fi
>> > @@ -407,6 +409,16 @@
>> >             unset -f python_pkg_setup_check_USE_flags
>> >     fi
>> >
>> > +   locale="$(python -c 'import os; print(os.environ.get("LC_ALL", os.environ.get("LC_CTYPE", os.environ.get("LANG", "POSIX"))))')"
>>
>> You're using python to get the exported env.  Don't.  Use bash (you're
>> invoking python from freaking bash after all)...
>
> Given variable can be set, but not exported.

If the variable is set but not exported then it is local to the shell
env.  When bash goes to exec() python the local shell variables are
not in the env; so os.environ() will not contain them.

antarus@kyoto ~ $ foo=BAR
antarus@kyoto ~ $ echo $foo
BAR
antarus@kyoto ~ $ python -c 'import os; print os.environ.get("foo")'
None
antarus@kyoto ~ $ export foo
antarus@kyoto ~ $ python -c 'import os; print os.environ.get("foo")'
BAR

so how is this any different than:

[[ -n $LC_TYPE ]] && locale=$LC_TYPE
[[ -n $LC_ALL ]] && locale=$LC_ALL
locale=${locale:-POSIX}

if you want to keep it short; or the longer version with more ifs and
less shell magic.  Normally I'm not a big performance man myself; but
this is in an eclass used by lots of packages; not just one ebuild.

>
>> bug 328047 is induced by a patch we add (it's not in upstream python).
>
> This patch comes from upstream.
>
> --
> Arfrever Frehtes Taifersar Arahesis
>