GNU bug report logs - #45355
26.1; shr-tag-base doesn't handle <base href=""> properly

Previous Next

To add a comment to this bug, you must first unarchive it, by sending
a message to control AT debbugs.gnu.org, with unarchive 45355 in the body.
You can then email your comments to 45355 AT debbugs.gnu.org in the normal way.

Toggle the display of automated, internal messages from the tracker.

Message #5 received at submit <at> debbugs.gnu.org (full text, mbox):

From: Łukasz Stelmach <steelman <at> post.pl>
To: bug-gnu-emacs <at> gnu.org
Subject: 26.1; shr-tag-base doesn't handle <base href=""> properly
Date: Mon, 21 Dec 2020 21:35:57 +0100

[Message part 1 (text/plain, inline)]

For what it's worth, W3C HTML Validator claims that a document with an
empty string in the href attribute of a base tag

    <base href="">

is valid. I found such document recently in my INBOX and Gnus was unable
to display it correctly because the second string-match in
shr-parse-base breaks when local is nil. My solution is not to call
shr-parse-base not only when href is not present but also when href is
an empty string.

The patch has been crated on the current master branch.
-- 
Kind regards,
Łukasz Stelmach

[0001-Handle-gracefully-href-in-base-tags.patch (text/x-diff, inline)]

From f92e8b8ab5b6f0970611c91cf80e418712ed2b58 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?=C5=81ukasz=20Stelmach?= <stlman <at> poczta.fm>
Date: Mon, 21 Dec 2020 21:07:28 +0100
Subject: [PATCH] Handle gracefully href="" in base tags

* net/shr.el (shr-tag-base): shr-parse-base can't handle empty strings
gracefully. Don't call it unless href is a non-empty string.
---
 lisp/net/shr.el | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/lisp/net/shr.el b/lisp/net/shr.el
index 2e5dd5ffa5..150ad88d4c 100644
--- a/lisp/net/shr.el
+++ b/lisp/net/shr.el
@@ -1516,8 +1516,9 @@ ones, in case fg and bg are nil."
       plist)))
 
 (defun shr-tag-base (dom)
-  (when-let* ((base (dom-attr dom 'href)))
-    (setq shr-base (shr-parse-base base)))
+  (let* ((base (dom-attr dom 'href)))
+    (when (> (length base) 0)
+      (setq shr-base (shr-parse-base base))))
   (shr-generic dom))
 
 (defun shr-tag-a (dom)
-- 
2.20.1

Message #8 received at 45355 <at> debbugs.gnu.org (full text, mbox):

From: Lars Ingebrigtsen <larsi <at> gnus.org>
To: Łukasz Stelmach <steelman <at> post.pl>
Cc: 45355 <at> debbugs.gnu.org
Subject: Re: bug#45355: 26.1; shr-tag-base doesn't handle <base href="">
 properly
Date: Tue, 22 Dec 2020 07:47:54 +0100

Łukasz Stelmach <steelman <at> post.pl> writes:

> For what it's worth, W3C HTML Validator claims that a document with an
> empty string in the href attribute of a base tag
>
>     <base href="">
>
> is valid. I found such document recently in my INBOX and Gnus was unable
> to display it correctly because the second string-match in
> shr-parse-base breaks when local is nil. My solution is not to call
> shr-parse-base not only when href is not present but also when href is
> an empty string.
>
> The patch has been crated on the current master branch.

Looks good to me; I've now applied it to Emacs 28.

-- 
(domestic pets only, the antidote for overdose, milk.)
   bloggy blog: http://lars.ingebrigtsen.no

Previous Next

GNU bug tracking system
Copyright (C) 1999 Darren O. Benham, 1997,2003 nCipher Corporation Ltd, 1994-97 Ian Jackson.