Re: [Qemu-devel] [PATCH v3 1/2] qapi: open files in binary mode and use explicit decoding/encoding in common.py

[Eduardo Habkost <ehabkost@redhat.com>]

On Mon, Jun 18, 2018 at 06:17:04PM -0300, Eduardo Habkost wrote:
> On Mon, Jun 18, 2018 at 07:54:26PM +0200, Markus Armbruster wrote:
> > Eduardo Habkost <ehabkost@redhat.com> writes:
> > 
> > > On Mon, Jun 18, 2018 at 07:25:14AM +0200, Markus Armbruster wrote:
> > >> Matthias Maier <tamiko@43-1.org> writes:
> > >> 
> > >> > This is a different approach to fix the locale dependent encode/decode
> > >> > problem in common.py utilizing the binary read/write mode [1,2], and (if
> > >> > a python 3 interpreter is used) with explicit decode/encode arguments
> > >> > [3].
> > >> 
> > >> Why can't we simply pass encoding='utf-8' to open()?
> > >
> > > This wouldn't work in Python 2.7 (where the `open()` builtin
> > > doesn't support the `encoding` parameter).
> > >
> > > io.open(..., encoding='utf-8') should work, though.
> > 
> > This falls apart because then f.read() returns objects of type 'unicode'
> > in Python 2, breaking isinstance(..., str) predicates in several places.
> 
> If the existing code already works with Python 3, we can import
> Python 3 string semantics in Python 2.7 so we have just one
> string API to care about.
> 
> This should do it:
> 
>   from __future__ import unicode_literals
>   from builtins import str
>   from builtins import open

Oops, I just noticed that this needs the 'future' package to be
installed.

I will submit a patch series later requiring python-future on
./configure.  In the meantime, probably your series is good
enough.

-- 
Eduardo