bug#34346: 26.1; Big hang when opening text (racket) files with .art extension (image-mode)

[Eli Zaretskii]

> From: Pierre Neidhardt <mail@ambrevar.xyz>
> Date: Wed, 06 Feb 2019 13:31:15 +0100
> 
> Tested with emacs -Q: opening a .art file
> (e.g. 
> https://raw.githubusercontent.com/euhmeuh/rilouw.eu/master/articles/hello.art)
> will hang Emacs for about a minute (on a rather powerful computer).  CPU
> is about 0% but disk I/O oscillates between 80MB/s-400MB/s (your mileage
> may vary).
> 
> It seems to be because Emacs tries to open the .art file in image-mode.
> The regexp seems to be added by imagemagick-register-types.
> 
> Removing .art from auto-mode-alist works.

Not sure I understand: are you saying that hello.art uses an extension
of some image files, but is not an image?  If so, why is that a bug --
these things can happen with any file, and removing an extension just
because there's one example to the contrary isn't necessarily a good
idea.

Or did I miss something?

Thanks.