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=-13.5 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,URIBL_BLOCKED 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 9E637C433ED for ; Sun, 25 Apr 2021 07:24:21 +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 DF16F61139 for ; Sun, 25 Apr 2021 07:24:20 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org DF16F61139 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]:33802 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1laZ7r-0003oY-LR for qemu-devel@archiver.kernel.org; Sun, 25 Apr 2021 03:24:19 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:60438) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1laZ7H-0003Q0-Qz for qemu-devel@nongnu.org; Sun, 25 Apr 2021 03:23:44 -0400 Received: from us-smtp-delivery-124.mimecast.com ([170.10.133.124]:40862) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1laZ7E-0002xM-IT for qemu-devel@nongnu.org; Sun, 25 Apr 2021 03:23:42 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1619335419; 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=NUC1UXwUrmqOOMZjGInenONALJ186g7113mLGF50nDQ=; b=B0gzZT+BbQdFY2sZ0jfeFwX03lrv8v3TxPDoKSXMVpg7nSTxzzDwQevCMGoIiml23H2slr gNe0cDxgXTAI09btfYiktLdQT3eOviDWFak1qdW/WH88h4l7IDGkQRFOnwCfwbaQW2TFSF qHCDIomGZaSOA7hGELPOkij8FL4f1do= 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-506-tAkKBDa6PDmnbFMumKZJ1A-1; Sun, 25 Apr 2021 03:23:36 -0400 X-MC-Unique: tAkKBDa6PDmnbFMumKZJ1A-1 Received: from smtp.corp.redhat.com (int-mx08.intmail.prod.int.phx2.redhat.com [10.5.11.23]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 52B2F107ACC7; Sun, 25 Apr 2021 07:23:35 +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 D622B19C46; Sun, 25 Apr 2021 07:23:34 +0000 (UTC) Received: by blackfin.pond.sub.org (Postfix, from userid 1000) id 67F7F113525D; Sun, 25 Apr 2021 09:23:33 +0200 (CEST) From: Markus Armbruster To: John Snow Subject: Re: [PATCH 06/22] qapi/parser: assert get_expr returns object in outer loop References: <20210422030720.3685766-1-jsnow@redhat.com> <20210422030720.3685766-7-jsnow@redhat.com> Date: Sun, 25 Apr 2021 09:23:33 +0200 In-Reply-To: <20210422030720.3685766-7-jsnow@redhat.com> (John Snow's message of "Wed, 21 Apr 2021 23:07:04 -0400") Message-ID: <87im4a96a2.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 2.84 on 10.5.11.23 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: > get_expr can return many things, depending on where it is used. In the > outer parsing loop, we expect and require it to return a dict. > > (It's (maybe) a bit involved to teach mypy that when nested is False, > this is already always True. I'll look into it later, maybe.) > > Signed-off-by: John Snow > --- > scripts/qapi/parser.py | 3 +++ > 1 file changed, 3 insertions(+) > > diff --git a/scripts/qapi/parser.py b/scripts/qapi/parser.py > index c75434e75a5..6b443b1247e 100644 > --- a/scripts/qapi/parser.py > +++ b/scripts/qapi/parser.py > @@ -78,6 +78,8 @@ def _parse(self): > continue > > expr = self.get_expr(False) > + assert isinstance(expr, dict) # Guaranteed when nested=False > + > if 'include' in expr: > self.reject_expr_doc(cur_doc) > if len(expr) != 1: > @@ -278,6 +280,7 @@ def get_values(self): > self.accept() > > def get_expr(self, nested): > + # TODO: Teach mypy that nested=False means the retval is a Dict. > if self.tok != '{' and not nested: > raise QAPIParseError(self, "expected '{'") > if self.tok == '{': The better place to assert a post condition would be ... self.accept() expr = self.get_members() elif self.tok == '[': self.accept() expr = self.get_values() elif self.tok in "'tf": expr = self.val self.accept() else: raise QAPIParseError( self, "expected '{', '[', string, or boolean") ... here. return expr But then it may not help mypy over the hump, which is the whole point of the patch. Alternative ways to skin this cat: * Split get_object() off get_expr(). diff --git a/scripts/qapi/parser.py b/scripts/qapi/parser.py index ca5e8e18e0..c79b3c7d08 100644 --- a/scripts/qapi/parser.py +++ b/scripts/qapi/parser.py @@ -262,9 +262,12 @@ def get_values(self): raise QAPIParseError(self, "expected ',' or ']'") self.accept() - def get_expr(self, nested): - if self.tok != '{' and not nested: + def get_object(self): + if self.tok != '{': raise QAPIParseError(self, "expected '{'") + return self.get_expr() + + def get_expr(self): if self.tok == '{': self.accept() expr = self.get_members() * Shift "top-level expression must be dict" up: diff --git a/scripts/qapi/parser.py b/scripts/qapi/parser.py index ca5e8e18e0..ee8cbf3531 100644 --- a/scripts/qapi/parser.py +++ b/scripts/qapi/parser.py @@ -68,7 +68,10 @@ def __init__(self, fname, previously_included=None, incl_info=None): self.docs.append(cur_doc) continue - expr = self.get_expr(False) + expr = self.get_expr() + if not isinstance(expr, OrderedDict): + raise QAPISemError( + info, "top-level expression must be an object") if 'include' in expr: self.reject_expr_doc(cur_doc) if len(expr) != 1: @@ -262,9 +265,7 @@ def get_values(self): raise QAPIParseError(self, "expected ',' or ']'") self.accept() - def get_expr(self, nested): - if self.tok != '{' and not nested: - raise QAPIParseError(self, "expected '{'") + def get_expr(self): if self.tok == '{': self.accept() expr = self.get_members() * Shift it further, into expr.py: diff --git a/scripts/qapi/expr.py b/scripts/qapi/expr.py index 496f7e0333..0a83c493a0 100644 --- a/scripts/qapi/expr.py +++ b/scripts/qapi/expr.py @@ -600,7 +600,10 @@ def check_exprs(exprs: List[_JSONObject]) -> List[_JSONObject]: """ for expr_elem in exprs: # Expression - assert isinstance(expr_elem['expr'], dict) + if not isinstance(expr_elem['expr'], dict): + raise QAPISemError( + info, "top-level expression must be an object") + for key in expr_elem['expr'].keys(): assert isinstance(key, str) expr: _JSONObject = expr_elem['expr'] Shifting it up would be closer to qapi-code-gen.txt than what we have now. All observations, no demands.