[PATCH 8 of 8] py3: have bytes version of sys.argv

[Yuya Nishihara]

On Sun, 06 Nov 2016 04:46:25 +0530, Pulkit Goyal wrote:
> # HG changeset patch
> # User Pulkit Goyal <7895pulkit at gmail.com>
> # Date 1478387186 -19800
> #      Sun Nov 06 04:36:26 2016 +0530
> # Node ID b5fc4e71286dd4f33336e4f38e0b9fb17f51f1e3
> # Parent  6eed3ee0df425da61d03bfe024dd082f3176ce5d
> py3: have bytes version of sys.argv
> 
> sys.argv returns unicodes on Python 3. We need a bytes version for us.
> There was also a python bug/feature request which wanted then to implement
> one. They rejected and it is quoted in one of the comments that we can use
> fsencode() to get a bytes version of sys.argv. Though not sure about its
> correctness.
> 
> Link to the comment: http://bugs.python.org/issue8776#msg217416
> 
> After this patch we will have pycompat.sysargv which will return us bytes
> version of sys.argv. If this patch goes in, i will like to make transformer
> rewrite sys.argv with pycompat.argv because there are lot of occurences.
> 
> diff -r 6eed3ee0df42 -r b5fc4e71286d mercurial/pycompat.py
> --- a/mercurial/pycompat.py	Sun Nov 06 04:17:19 2016 +0530
> +++ b/mercurial/pycompat.py	Sun Nov 06 04:36:26 2016 +0530
> @@ -41,6 +41,7 @@
>      osname = os.name.encode('ascii')
>      ospathsep = os.pathsep.encode('ascii')
>      ossep = os.sep.encode('ascii')
> +    sysargv = list(map(os.fsencode, sys.argv))

Looks good to me. Can you add a comment why we can use os.fsencode() here
(and the weirdness of Python 3 on Unix.) We might need a Windows workaround
because the situation is slightly different, but we wouldn't want to care
for now.