[PATCH 3 of 3 v2] run-tests: use strings for env object

[Yuya Nishihara]

On Thu, 5 May 2016 08:48:00 -0400, timeless wrote:
> It's possible. I really don't want to do it.
> This whole thing is a mess. If someone else wants to do that and save
> me from another 24 hours of encoding hell, i'd be appreciative.
> 
> This is probably the fourth or fifth night I've lost trying to fight encodings.
> 
> On Thu, May 5, 2016 at 8:17 AM, Pierre-Yves David
> <pierre-yves.david at ens-lyon.org> wrote:
> >
> >
> > On 05/05/2016 01:09 PM, timeless wrote:  
> >>
> >> I just spent some time investigating this.
> >>
> >> The answer is: NO. WE SHOULD NOT USE environb.
> >>
> >> That's an awful red herring.
> >>
> >> os.environb
> >>
> >> Bytes version of environ: a mapping object representing the
> >> environment as byte strings. environ and environb are synchronized
> >> (modify environb updates environ, and vice versa).
> >>
> >> environb is only available if supports_bytes_environ is True.
> >>
> >> New in version 3.2.
> >>
> >> https://docs.python.org/3/library/os.html#os.environb
> >>
> >> os.supports_bytes_environ
> >>
> >> True if the native OS type of the environment is bytes (eg. False on
> >> Windows).
> >>
> >> New in version 3.2.
> >>
> >> https://docs.python.org/3/library/os.html#os.supports_bytes_environ
> >>
> >> Trying to use environb would break python3 on windows because we'd
> >> have an os.environ object instead of an os.environb object, and we'd
> >> be trying to stash bytes into it.
> >>
> >> I'm going to reassert that what I'm doing is correct. And I'd like to
> >> get a version of it in so that I can unclutter my repository. I have a
> >> whole slew of things that are blocked by this. Especially test.env
> >> work.
> >>
> >> I will send a patch to *REMOVE* all use of environb and an item for
> >> check code to reject it.  
> >
> > Could we have a version that use environb implementing a thin layer in the
> > window case to provide an environb like object in this case?

Writing a thin environb would be easy if we don't have to update the real
environment variables in flight. Is it difficult to make run-tests.py use
subprocess.Popen() and pass env explicitly?

Anyway we'll need environb and Popen() wrappers to make hg work on Python3
on Windows.