From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-11.1 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, NICE_REPLY_A,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED, USER_AGENT_SANE_1 autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 83815C43461 for ; Wed, 16 Sep 2020 22:26:36 +0000 (UTC) Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id CD194206A5 for ; Wed, 16 Sep 2020 22:26:35 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="WLnB/f18" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org CD194206A5 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Received: from localhost ([::1]:36874 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1kIfso-0003hO-Iw for qemu-devel@archiver.kernel.org; Wed, 16 Sep 2020 18:26:34 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:55934) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1kIfrX-0002jR-3I for qemu-devel@nongnu.org; Wed, 16 Sep 2020 18:25:15 -0400 Received: from us-smtp-delivery-124.mimecast.com ([63.128.21.124]:27498) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_CBC_SHA1:256) (Exim 4.90_1) (envelope-from ) id 1kIfrU-0007fe-CQ for qemu-devel@nongnu.org; Wed, 16 Sep 2020 18:25:14 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1600295110; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=UcRDqCo6NK5l1vF9GKZHmI737xr7NANUPqKCdW3QC7k=; b=WLnB/f18tfUTM9u0zdE7IjEhmgLxWmCX3dr2PFZiNYhmLtVdtOWWGXJn99hIpcyeAI9qGP 59K/tSNh1Ej/40vRtsso+1dlzFOdVom1woG3QHZcJDX7b9Xwkc+3oreSdZWEDbZFRKK38R P18lmgfoDWwKOthv0tTWqD0rMRjUaEQ= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-306-xcxSMhk_Mj-D8nU9U-Nh9w-1; Wed, 16 Sep 2020 18:25:07 -0400 X-MC-Unique: xcxSMhk_Mj-D8nU9U-Nh9w-1 Received: from smtp.corp.redhat.com (int-mx04.intmail.prod.int.phx2.redhat.com [10.5.11.14]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 7AE4580572E; Wed, 16 Sep 2020 22:25:06 +0000 (UTC) Received: from [10.10.119.140] (ovpn-119-140.rdu2.redhat.com [10.10.119.140]) by smtp.corp.redhat.com (Postfix) with ESMTP id 3021F5D9E8; Wed, 16 Sep 2020 22:25:05 +0000 (UTC) Subject: Re: [PATCH 09/37] qapi/common.py: Add indent manager To: Markus Armbruster References: <20200915224027.2529813-1-jsnow@redhat.com> <20200915224027.2529813-10-jsnow@redhat.com> <87k0wtiwlb.fsf@dusky.pond.sub.org> From: John Snow Message-ID: <37ea889c-746e-bea9-a719-6bee9e86f1a8@redhat.com> Date: Wed, 16 Sep 2020 18:25:04 -0400 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.11.0 MIME-Version: 1.0 In-Reply-To: <87k0wtiwlb.fsf@dusky.pond.sub.org> X-Scanned-By: MIMEDefang 2.79 on 10.5.11.14 Authentication-Results: relay.mimecast.com; auth=pass smtp.auth=CUSA124A263 smtp.mailfrom=jsnow@redhat.com X-Mimecast-Spam-Score: 0.002 X-Mimecast-Originator: redhat.com Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 7bit Content-Language: en-US Received-SPF: pass client-ip=63.128.21.124; envelope-from=jsnow@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-detected-operating-system: by eggs.gnu.org: First seen = 2020/09/16 02:35:56 X-ACL-Warn: Detected OS = Linux 2.2.x-3.x [generic] [fuzzy] X-Spam_score_int: -51 X-Spam_score: -5.2 X-Spam_bar: ----- X-Spam_report: (-5.2 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-2.999, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, NICE_REPLY_A=-0.062, RCVD_IN_DNSWL_NONE=-0.0001, RCVD_IN_MSPIKE_H5=0.001, RCVD_IN_MSPIKE_WL=0.001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Peter Maydell , Cleber Rosa , =?UTF-8?Q?Alex_Benn=c3=a9e?= , qemu-devel@nongnu.org, Eduardo Habkost Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" On 9/16/20 11:13 AM, Markus Armbruster wrote: > John Snow writes: > >> Code style tools really dislike the use of global keywords, because it >> generally involves re-binding the name at runtime which can have strange >> effects depending on when and how that global name is referenced in >> other modules. >> >> Make a little indent level manager instead. >> >> Signed-off-by: John Snow >> --- >> scripts/qapi/common.py | 50 +++++++++++++++++++++++++++++------------- >> scripts/qapi/visit.py | 7 +++--- >> 2 files changed, 38 insertions(+), 19 deletions(-) >> >> diff --git a/scripts/qapi/common.py b/scripts/qapi/common.py >> index 4fb265a8bf..87d87b95e5 100644 >> --- a/scripts/qapi/common.py >> +++ b/scripts/qapi/common.py >> @@ -93,33 +93,53 @@ def c_name(name, protect=True): >> pointer_suffix = ' *' + eatspace >> >> >> -def genindent(count): >> - ret = '' >> - for _ in range(count): >> - ret += ' ' >> - return ret >> +class Indent: > > Since this class name will be used just once... Indentation or > IndentationManager? > Indentation is fine, if you'd like. IndentationManager makes me feel ashamed for writing this patch, like I am punishing myself with Java. >> + """ >> + Indent-level management. >> >> + :param initial: Initial value, default 0. > > The only caller passes 0. > > Let's drop the parameter, and hardcode the default initial value until > we have an actual use for another initial value. > The parameter is nice because it gives meaning to the output of repr(), see below. >> + """ >> + def __init__(self, initial: int = 0) -> None: >> + self._level = initial >> >> -indent_level = 0 >> + def __int__(self) -> int: >> + """Return the indent as an integer.""" > > Isn't "as an integer" obvious? Just a compulsion to write complete sentences that got lost in the sea of many patches. I'll nix this one, because dunder methods do not need to be documented. > > Let's replace "the indent" by "the indentation" globally. > They're both cromulent as nouns and one is shorter. I'll switch in good faith; do you prefer "Indentation" as a noun? >> + return self._level >> >> + def __repr__(self) -> str: >> + return "{}({:d})".format(type(self).__name__, self._level) > > Is __repr__ needed? > Yes; it's used in the underflow exception , and it is nice when using the python shell interactively. repr(Indent(4)) == "Indent(4)" >> >> -def push_indent(indent_amount=4): >> - global indent_level >> - indent_level += indent_amount >> + def __str__(self) -> str: >> + """Return the indent as a string.""" >> + return ' ' * self._level >> >> + def __bool__(self) -> bool: >> + """True when there is a non-zero indent.""" >> + return bool(self._level) > > This one lets us shorten > > if int(INDENT): > > to > > if INDENT: > > There's just one instance. Marginal. I'm not rejecting it. > Yep, it's trivial in either direction. Still, because it's a custom type, I thought I'd be courteous and have it support bool(). >> -def pop_indent(indent_amount=4): >> - global indent_level >> - indent_level -= indent_amount >> + def push(self, amount: int = 4) -> int: >> + """Push `amount` spaces onto the indent, default four.""" >> + self._level += amount >> + return self._level >> + >> + def pop(self, amount: int = 4) -> int: >> + """Pop `amount` spaces off of the indent, default four.""" >> + if self._level < amount: >> + raise ArithmeticError( >> + "Can't pop {:d} spaces from {:s}".format(amount, repr(self))) >> + self._level -= amount >> + return self._level > > The push / pop names never made sense. The functions don't push onto / > pop from a stack, they increment / decrement a counter, and so do the > methods. Good opportunity to fix the naming. > OK. I briefly thought about using __isub__ and __iadd__ to support e.g. indent += 4, but actually it'd be annoying to have to specify 4 everywhere. Since you didn't suggest anything, I am going to change it to 'increase' and 'decrease'. > The @amount parameter has never been used. I don't mind keeping it. > I'll keep it, because I like having the default amount show up in the signature instead of as a magic constant in the function body. >> + >> + >> +INDENT = Indent(0) > > Uh, does this really qualify as a constant? It looks quite variable to > me... > Ever make a mistake? I thought I did once, but I was mistaken. >> # Generate @code with @kwds interpolated. >> # Obey indent_level, and strip eatspace. >> def cgen(code, **kwds): >> raw = code % kwds >> - if indent_level: >> - indent = genindent(indent_level) >> - raw, _ = re.subn(r'^(?!(#|$))', indent, raw, flags=re.MULTILINE) >> + if INDENT: >> + raw, _ = re.subn(r'^(?!(#|$))', str(INDENT), raw, flags=re.MULTILINE) >> return re.sub(re.escape(eatspace) + r' *', '', raw) >> >> >> diff --git a/scripts/qapi/visit.py b/scripts/qapi/visit.py >> index 31bf46e7f7..66ce3dc52e 100644 >> --- a/scripts/qapi/visit.py >> +++ b/scripts/qapi/visit.py >> @@ -19,8 +19,7 @@ >> gen_endif, >> gen_if, >> mcgen, >> - pop_indent, >> - push_indent, >> + INDENT, >> ) >> from .gen import QAPISchemaModularCVisitor, ifcontext >> from .schema import QAPISchemaObjectType >> @@ -68,7 +67,7 @@ def gen_visit_object_members(name, base, members, variants): >> if (visit_optional(v, "%(name)s", &obj->has_%(c_name)s)) { >> ''', >> name=memb.name, c_name=c_name(memb.name)) >> - push_indent() >> + INDENT.push() >> ret += mcgen(''' >> if (!visit_type_%(c_type)s(v, "%(name)s", &obj->%(c_name)s, errp)) { >> return false; >> @@ -77,7 +76,7 @@ def gen_visit_object_members(name, base, members, variants): >> c_type=memb.type.c_name(), name=memb.name, >> c_name=c_name(memb.name)) >> if memb.optional: >> - pop_indent() >> + INDENT.pop() >> ret += mcgen(''' >> } >> ''')