[debbugs-tracker] bug#19768: closed (json.el: end-of-file errors untrappable)

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Your message dated Thu, 05 Feb 2015 14:52:39 -0500
with message-id <address@hidden>
and subject line Re: bug#19768: json.el: end-of-file errors untrappable
has caused the debbugs.gnu.org bug report #19768,
regarding json.el: end-of-file errors untrappable
to be marked as done.

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19768: http://debbugs.gnu.org/cgi/bugreport.cgi?bug=19768
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> --- Begin Message ---
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>
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> Subject: 
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> json.el: end-of-file errors untrappable
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>
>
>
> Date: 
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> Wed, 04 Feb 2015 15:59:43 +0200
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>
> Package: emacs
> Version: 24.3.1
> X-Debbugs-Cc: address@hidden
>
> The code in json.el uses (signal 'end-of-file) in many scenarios. 
> Unfortunately, the default value of debug-ignore-errors causes these
> errors to bypass any error checking, and unhelpfully land in the
> *Messages* buffer with little indication as to what went wrong or which
> code path caused this message.
>
> Once you know this, debugging json-read is easy; but the fix is
> unobvious, and might have unintended side effects.
>
> Steps to repro:
>
>     (require 'json)
>     (setq debug-on-error t)
>     (json-read-from-string "")
>
> Expected result:
>
> *Backtrace* showing where something went wrong
>
> Actual result:
>
> json-read: End of file during parsing
>
> (The "json-read:" prefix is not visible in the minibuffer message for
> me, but it lands in the *Messages* buffer.)
>
> Workaround:
>
>     (let (debug-ignore-errors)
>       (json-read-from-string ""))
>
> I'm not sure what the proper fix should be.  Maybe these occurrences
> could be changed to json-end-of-file or something?  Or maybe json-read
> could include the 'let' form from the workaround.
>
> See also:
> http://stackoverflow.com/questions/28317081/debug-on-error-vs-debug-on-signal-in-json-el-in-particular
>
> /* era */
>
> -- 
> If this were a real .signature, it would suck less.  Well, maybe not.
>
>
>
> --- End Message ---
> --- Begin Message ---
>
>
>
> Subject: 
>
> Re: bug#19768: json.el: end-of-file errors untrappable
>
>
>
>
> Date: 
>
> Thu, 05 Feb 2015 14:52:39 -0500
>
>
>
>
> User-agent: 
>
> Gnus/5.13 (Gnus v5.13) Emacs/25.0.50 (gnu/linux)
>
>
>
>
> > https://github.com/tripleee/emacs/tree/bug19768 contains a simple patch
> > which implements this, but I am uncertain how to test it.  Also, I am
> > having second thoughts about defining the new error symbol as a child of
> > 'end-of-file when all the other error symbols neatly inherit from
> > 'json-error.  Anyway, feel free to review and/or pull and/or ignore. (-:
>
> Installed, making it inherit from both kinds of errors ;-)
>
>
>         Stefan
>
>
> --- End Message ---