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 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 smtp.lore.kernel.org (Postfix) with ESMTPS id A9B2FC636CC for ; Sat, 11 Feb 2023 10:07:06 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1pQmm7-0003JZ-Bu; Sat, 11 Feb 2023 05:06:31 -0500 Received: from eggs.gnu.org ([2001:470:142:3::10]) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1pQmm5-0003Fe-0g for qemu-devel@nongnu.org; Sat, 11 Feb 2023 05:06:29 -0500 Received: from us-smtp-delivery-124.mimecast.com ([170.10.129.124]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1pQmm2-0008GZ-H5 for qemu-devel@nongnu.org; Sat, 11 Feb 2023 05:06:28 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1676109985; 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=ylbCv6HUkisP01xe7akPPHagbWAjiqZq6mYxMiRImk0=; b=N0D0fNWSUO6kvSpdySqj19IKg5JmG4t7PlTPRakGjXNiodtaCKxycMfib9fzK00SRJwGFP Kbpb+qCUzclEePQNmTvXk4Gl+c61Eni2pRg8+OAjcjFFiEgOATlMRIZoPOX/+ajuO1EpXL 7X6+SorRsoEiLUqkaZHSnm9FCbFEzBo= Received: from mimecast-mx02.redhat.com (mx3-rdu2.redhat.com [66.187.233.73]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-91-aSsgAwPxPk2T8em5t29PoQ-1; Sat, 11 Feb 2023 05:06:23 -0500 X-MC-Unique: aSsgAwPxPk2T8em5t29PoQ-1 Received: from smtp.corp.redhat.com (int-mx05.intmail.prod.int.rdu2.redhat.com [10.11.54.5]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id E3CD61C05145; Sat, 11 Feb 2023 10:06:22 +0000 (UTC) Received: from blackfin.pond.sub.org (unknown [10.39.193.101]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 9F9CC51FF; Sat, 11 Feb 2023 10:06:22 +0000 (UTC) Received: by blackfin.pond.sub.org (Postfix, from userid 1000) id A5F5721E6A1F; Sat, 11 Feb 2023 11:06:21 +0100 (CET) From: Markus Armbruster To: John Snow Cc: qemu-devel , Michael Roth Subject: Re: [PATCH v3 3/7] qapi/expr: Split check_expr out from check_exprs References: <20230209184758.1017863-1-jsnow@redhat.com> <20230209184758.1017863-4-jsnow@redhat.com> <87pmahr983.fsf@pond.sub.org> Date: Sat, 11 Feb 2023 11:06:21 +0100 In-Reply-To: (John Snow's message of "Fri, 10 Feb 2023 10:20:11 -0500") Message-ID: <874jrs349u.fsf@pond.sub.org> User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/28.2 (gnu/linux) MIME-Version: 1.0 Content-Type: text/plain X-Scanned-By: MIMEDefang 3.1 on 10.11.54.5 Received-SPF: pass client-ip=170.10.129.124; envelope-from=armbru@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -20 X-Spam_score: -2.1 X-Spam_bar: -- X-Spam_report: (-2.1 / 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_NONE=-0.0001, RCVD_IN_MSPIKE_H2=-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: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org John Snow writes: > --0000000000003b01fe05f45a096a > Content-Type: text/plain; charset="UTF-8" > > On Fri, Feb 10, 2023, 7:33 AM Markus Armbruster wrote: > >> Another observation... >> >> John Snow writes: >> >> > Primarily, this reduces a nesting level of a particularly long >> > block. It's mostly code movement, but a new docstring is created. >> > >> > It also has the effect of creating a fairly convenient "catch point" in >> > check_exprs for exception handling without making the nesting level even >> > worse. >> > > What I mean is: If you want to handle exceptions without this patch, a > try/catch will add another nesting level to this hundred line function. > > By splitting it, you can use the outer looping function as a choke point to > write the handler. > > I had a branch once where I use this fact to stop routing "info" into 99% > of expr.py. I did this to use an off the shelf JSON validator while > preserving your custom source info error reporting that identifies the > precise location of the error. When you have to reindent anyway, the drawback "makes git-blame less useful" evaporates. When the reindent is due to another level of nesting, the benefit "reduces nesting" becomes more valuable. > I took that out for now, in the interest of staying focused on the minimum > viable to achieve strict typing, but found this change to be helpful anyway. > > Admit that it does muddy the waters with git blame, but... my calculus on > that might just be different from yours. > > (To me, git blame is almost always something I have to trace back through > several refactors anyway, so I see the battle as lost before I started.) > > I can omit this patch for now if you'd like, it isn't crucial. I just think > I'd still "kinda like to have it". I'll leave it up to you. I'd prefer to shelve it for now. Bring it back when we have to reindent anyway. >> > Signed-off-by: John Snow >> > >> > --- >> > >> > This patch was originally written as part of my effort to factor out >> > QAPISourceInfo from this file by having expr.py raise a simple >> > exception, then catch and wrap it at the higher level. >> > >> > This series doesn't do that anymore, but reducing the nesting level >> > still seemed subjectively nice. It's not crucial. >> > >> > Signed-off-by: John Snow >> > > Whoops, script doesn't understand when I add notes. > >> --- >> > scripts/qapi/expr.py | 179 +++++++++++++++++++++++-------------------- >> > 1 file changed, 95 insertions(+), 84 deletions(-) >> > >> > diff --git a/scripts/qapi/expr.py b/scripts/qapi/expr.py >> > index 5a1782b57ea..b56353bdf84 100644 >> > --- a/scripts/qapi/expr.py >> > +++ b/scripts/qapi/expr.py >> > @@ -595,6 +595,99 @@ def check_event(expr: _JSONObject, info: >> QAPISourceInfo) -> None: >> > check_type(args, info, "'data'", allow_dict=not boxed) >> > >> > >> > +def check_expr(expr_elem: _JSONObject) -> None: >> >> [...] >> >> > def check_exprs(exprs: List[_JSONObject]) -> List[_JSONObject]: >> > """ >> > Validate and normalize a list of parsed QAPI schema expressions. >> >> The typing is kind of wrong. >> >> The list is the value of QAPISchemaParser.exprs, which is (losely) typed >> as List[Dict[str, object]]. It is actually a dict mapping >> >> 'expr' -> _ExprValue >> 'info' -> QAPISourceInfo >> 'doc' -> Optional[QAPIDoc] >> >> Thet's not what _JSONObject is! Its doc string describes it as >> "Deserialized JSON objects as returned by the parser", i.e. the same as >> _ExprValue. >> >> Works only because _JSONObject is a dict mapping arbitrary keys to >> _JSONObject, str or bool. >> >> This patch spreads the flawed typing to the new function. >> >> Gets healed later in the series. >> > > Oops...! > > Symptom of patch reordering that happened some time ago, I think. Mea > culpa. Will fix. > > (Possibly with some ugly intermediate type that goes away by end of series.) Only if it's dead easy. Simply have the commit message point out there's problem being fixed? >> [...]