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=-13.6 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS 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 00E48C433DB for ; Thu, 25 Mar 2021 05:48:10 +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 7475E61974 for ; Thu, 25 Mar 2021 05:48:09 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 7475E61974 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]:51916 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1lPIqm-0007AL-IO for qemu-devel@archiver.kernel.org; Thu, 25 Mar 2021 01:48:08 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:37704) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1lPIpU-0006bH-9y for qemu-devel@nongnu.org; Thu, 25 Mar 2021 01:46:48 -0400 Received: from us-smtp-delivery-124.mimecast.com ([170.10.133.124]:27356) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1lPIpS-0006c5-DB for qemu-devel@nongnu.org; Thu, 25 Mar 2021 01:46:48 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1616651204; 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: in-reply-to:in-reply-to:references:references; bh=qkTTkbmEHDl7sA0q2fOizVXtrifvUuD5V30OlBWoT7Y=; b=DrCpvmbxQqSM1yrzrYFza/HgVM1NCCePZftsyIMMZm7bJ01tWVgKthbzc1qiUUU3GoOTNx 8eyHf2W0RIpB/z/+mw9OT0cjH2td/XGg7rtNf0P+MCi0akCCWKGPGDqYgS1z7rVtfLlO2F PP0DHl1P2zLTXig3xlmLdPCgmAfc4Do= 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-356-JqOIPwXGPGWX_ZURbjatzQ-1; Thu, 25 Mar 2021 01:46:41 -0400 X-MC-Unique: JqOIPwXGPGWX_ZURbjatzQ-1 Received: from smtp.corp.redhat.com (int-mx01.intmail.prod.int.phx2.redhat.com [10.5.11.11]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 298FD18C89D9; Thu, 25 Mar 2021 05:46:41 +0000 (UTC) Received: from blackfin.pond.sub.org (ovpn-114-17.ams2.redhat.com [10.36.114.17]) by smtp.corp.redhat.com (Postfix) with ESMTPS id D143D9CA0; Thu, 25 Mar 2021 05:46:40 +0000 (UTC) Received: by blackfin.pond.sub.org (Postfix, from userid 1000) id 66E2111327E1; Thu, 25 Mar 2021 06:46:39 +0100 (CET) From: Markus Armbruster To: John Snow Subject: Re: [PATCH v3 04/16] qapi/expr.py: Add assertion for union type 'check_dict' References: <20210223003408.964543-1-jsnow@redhat.com> <20210223003408.964543-5-jsnow@redhat.com> <874ki169dg.fsf@dusky.pond.sub.org> Date: Thu, 25 Mar 2021 06:46:39 +0100 In-Reply-To: (John Snow's message of "Wed, 24 Mar 2021 17:09:13 -0400") Message-ID: <87wntvaips.fsf@dusky.pond.sub.org> User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/27.1 (gnu/linux) MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.11 Authentication-Results: relay.mimecast.com; auth=pass smtp.auth=CUSA124A263 smtp.mailfrom=armbru@redhat.com X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Type: text/plain Received-SPF: pass client-ip=170.10.133.124; envelope-from=armbru@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -27 X-Spam_score: -2.8 X-Spam_bar: -- X-Spam_report: (-2.8 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.001, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_LOW=-0.7, RCVD_IN_MSPIKE_H4=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: Michael Roth , qemu-devel@nongnu.org, Eduardo Habkost , Cleber Rosa Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" John Snow writes: > On 2/24/21 5:35 AM, Markus Armbruster wrote: >> John Snow writes: >> >>> mypy isn't fond of allowing you to check for bool membership in a >>> collection of str elements. Guard this lookup for precisely when we were >>> given a name. >>> >>> Signed-off-by: John Snow >>> Reviewed-by: Eduardo Habkost >>> Reviewed-by: Cleber Rosa >>> --- >>> scripts/qapi/expr.py | 4 +++- >>> 1 file changed, 3 insertions(+), 1 deletion(-) >>> >>> diff --git a/scripts/qapi/expr.py b/scripts/qapi/expr.py >>> index 783282b53ce..138fab0711f 100644 >>> --- a/scripts/qapi/expr.py >>> +++ b/scripts/qapi/expr.py >>> @@ -173,7 +173,9 @@ def check_type(value, info, source, >>> raise QAPISemError(info, >>> "%s should be an object or type name" % source) >>> - permit_upper = allow_dict in info.pragma.name_case_whitelist >>> + permit_upper = False >>> + if isinstance(allow_dict, str): >>> + permit_upper = allow_dict in info.pragma.name_case_whitelist >>> # value is a dictionary, check that each member is okay >>> for (key, arg) in value.items(): >> >> Busy-work like this can make me doubt typing is worth the notational >> overhead. >> There must a less awkward way to plumb "upper case okay" through >> check_type() to check_name_is_str(). But we're typing what we have. > > Leaving this as-is for now. There's something I'd like to do about it, > but it has to happen later. > > (I think all the pragma checks should happen in schema.py, and not in > expr.py. They are by their essence not context-free, since they depend > on the context of the pragma.) True. Pragmas other than doc-required are an ugly consequence of us having made a a bit of a mess in the schema. The oldest parts of the schema were set in stone before we decided on certain rules, and then we kept failing at manually enforcing these rules. To get automatic enforcement, we needed a way to give a pass to existing rule breakers. Preferably without rearchitecting the frontend. Pragmas solve that problem. The solution is as ugly as the problem. Without pragmas, the name checks are context-free. That's why they are where they are.