GNU bug report logs - #37706
`inhibit-message' affects error backtrace printing in batch mode

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 37706 in the body.
You can then email your comments to 37706 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: Paul Pogonyshev <pogonyshev <at> gmail.com>
To: bug-gnu-emacs <at> gnu.org
Subject: `inhibit-message' affects error backtrace printing in batch mode
Date: Fri, 11 Oct 2019 19:17:51 +0200

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

When in batch mode, `debug-on-error' can be used to make Emacs
print backtraces of any errors that occur:

    $ emacs --batch --eval "(let ((debug-on-error t)) (error \"...\"))"
    Error: (error (error "..."))
      (signal error ("..."))
      (error "...")
      (let ((debug-on-error t)) (error "..."))
      (eval (let ((debug-on-error t)) (error "...")) t)
      (command-line-1 ("--eval" "(let ((debug-on-error t)) (error \"...\"))"))
      (command-line)
      (normal-top-level)
    ...

However, variable `inhibit-message' affects it:

    $ emacs --batch --eval "(let ((debug-on-error t) (inhibit-message
t)) (error \"...\"))"
    ...

This is wrong.  When binding `inhibit-message' you have no idea
that an error might happen inside the block.  Actually, you
rather hope it doesn't.  In other words, when binding
`inhibit-message' you never target error backtraces -- those are
only unwanted side-effects of bugs in your code.

Attached patch makes function `debug' temporarily rebind
`inhibit-message' to nil. The patch is just three lines, but `diff'
got mad because of reindentation.

Paul

[0001-Explicitly-bind-inhibit-message-to-nil-in-debug.patch (text/x-patch, attachment)]

Message #8 received at 37706 <at> debbugs.gnu.org (full text, mbox):

From: Lars Ingebrigtsen <larsi <at> gnus.org>
To: Paul Pogonyshev <pogonyshev <at> gmail.com>
Cc: 37706 <at> debbugs.gnu.org
Subject: Re: bug#37706: `inhibit-message' affects error backtrace printing
 in batch mode
Date: Thu, 20 Aug 2020 17:10:33 +0200

Paul Pogonyshev <pogonyshev <at> gmail.com> writes:

> When in batch mode, `debug-on-error' can be used to make Emacs
> print backtraces of any errors that occur:

[...]

> This is wrong.  When binding `inhibit-message' you have no idea
> that an error might happen inside the block.  Actually, you
> rather hope it doesn't.  In other words, when binding
> `inhibit-message' you never target error backtraces -- those are
> only unwanted side-effects of bugs in your code.
>
> Attached patch makes function `debug' temporarily rebind
> `inhibit-message' to nil. The patch is just three lines, but `diff'
> got mad because of reindentation.

Thanks for the patch -- it looks like this was fixed by this commit:

commit 502059433ce0e9699eb73d21656ce6e9e127d63b
Author:     Paul Pogonyshev <pogonyshev <at> gmail.com>
AuthorDate: Sun Jan 26 22:54:32 2020 -0500

    * lisp/emacs-lisp/debug.el (debug): Merge the non-interactive cases
    
    bug#38927


-- 
(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.