From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:37734) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1fVFC3-00021W-2m for qemu-devel@nongnu.org; Tue, 19 Jun 2018 07:53:04 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1fVFBz-00057i-5M for qemu-devel@nongnu.org; Tue, 19 Jun 2018 07:53:03 -0400 Received: from mx3-rdu2.redhat.com ([66.187.233.73]:57388 helo=mx1.redhat.com) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1fVFBy-00057O-WD for qemu-devel@nongnu.org; Tue, 19 Jun 2018 07:52:59 -0400 From: Markus Armbruster References: <20180618175958.29073-1-armbru@redhat.com> <20180618175958.29073-2-armbru@redhat.com> <20180618213526.GJ24764@localhost.localdomain> <87tvpzz3wn.fsf@dusky.pond.sub.org> <20180619105032.GO7451@localhost.localdomain> Date: Tue, 19 Jun 2018 13:52:56 +0200 In-Reply-To: <20180619105032.GO7451@localhost.localdomain> (Eduardo Habkost's message of "Tue, 19 Jun 2018 07:50:32 -0300") Message-ID: <87bmc7vvqf.fsf@dusky.pond.sub.org> MIME-Version: 1.0 Content-Type: text/plain Subject: Re: [Qemu-devel] [PATCH v4 1/2] qapi: Open files with encoding='utf-8' List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Eduardo Habkost Cc: Markus Armbruster , tamiko@43-1.org, qemu-devel@nongnu.org, arfrever.fta@gmail.com Eduardo Habkost writes: > On Tue, Jun 19, 2018 at 08:28:08AM +0200, Markus Armbruster wrote: >> Eduardo Habkost writes: >> >> > On Mon, Jun 18, 2018 at 07:59:57PM +0200, Markus Armbruster wrote: >> >> Python 2 happily reads UTF-8 files in text mode, but Python 3 requires >> >> either UTF-8 locale or an explicit encoding passed to open(). Commit >> >> d4e5ec877ca fixed this by setting the en_US.UTF-8 locale. Falls apart >> >> when the locale isn't be available. >> >> >> >> Matthias Maier and Arfrever Frehtes Taifersar Arahesis proposed to use >> >> binary mode instead, with manual conversion from bytes to str. Works, >> >> but opening with an explicit encoding is simpler, so do that. >> >> >> >> Since Python 2's open() doesn't support the encoding parameter, we >> >> need to suppress it with a version check. >> >> >> >> Reported-by: Arfrever Frehtes Taifersar Arahesis >> >> Reported-by: Matthias Maier >> >> Signed-off-by: Markus Armbruster >> >> --- >> >> scripts/qapi/common.py | 17 ++++++++++++++--- >> >> 1 file changed, 14 insertions(+), 3 deletions(-) >> >> >> >> diff --git a/scripts/qapi/common.py b/scripts/qapi/common.py >> >> index 2462fc0291..832f11438a 100644 >> >> --- a/scripts/qapi/common.py >> >> +++ b/scripts/qapi/common.py >> >> @@ -16,6 +16,7 @@ import errno >> >> import os >> >> import re >> >> import string >> >> +import sys >> >> from collections import OrderedDict >> >> >> >> builtin_types = { >> >> @@ -340,7 +341,10 @@ class QAPISchemaParser(object): >> >> return None >> >> >> >> try: >> >> - fobj = open(incl_fname, 'r') >> >> + if sys.version_info[0] >= 3: >> >> + fobj = open(incl_fname, 'r', encoding='utf-8') >> >> + else: >> >> + fobj = open(incl_fname, 'r') >> > >> > I dislike the Python version check, but getting rid of it would >> > require rewriting the QAPI modules to not use the Python 2 str >> > type (that has different semantics from Python 3 str type). >> >> The version check is ugly, but it has a property I rather like: when we >> drop support for Python 2, the conditional becomes True, and partial >> evaluation results in the Python 3 code we actually want. >> >> > The python-future package would help us write code for a single >> > file/string API instead of two different APIs, but it's not a >> > QEMU build dependency (yet?), so this patch is good enough for >> > now. >> >> Please do not invest more than absolutely necessary in Python 2 support. >> All such investment will turn into technical debt in less than two >> years. If you must invest, pick a solution that will result in less >> technical debt. We can accept local ugliness for that. >> >> In my personal opinion, dumb ideas like supporting Python 2 this close >> to its EOL ought to look ugly. > > That's the whole point: python-future allows us to not worry > about Python 2 support in the code anymore because it exposes the > Python 3 string API (and others) even if we're running Python 2. > > After we stop supporting Python 2, we can simply delete the "from > __future__ import .*" and "from builtins import .*" lines. You're right, __future__ is one of the least annoying ways to keep Python 2 working. But is the improvement over my stupid, ugly solution worth your while? You decide. > Anyway, I will send a RFC series demonstrating that, and then we > can discuss if it's worth it. My main worry is not the extra > imports in Python code, but the introduction of a new build > dependency only for a few (one?) releases. The sane extra dependency to add would be Python 3. Not worth arguing again; time's on my side ;) >> > Reviewed-by: Eduardo Habkost >> > Acked-by: Eduardo Habkost >> >> Uh, what does "Acked-by" add over "Reviewed-by"? > > It was supposed to indicate that I agree it can be merged through > other maintainers. But it looks like this is not part of the > original definition of "Acked-by"? I'll drop the Acked-by then.