[13.0.0] TeX-auto-parse-region: Wrong type argument: stringp, nil

[Denis Bitouzé]

Hi,

since AUCTeX has been updated to 13.0.0, it cannot be used anymore with
GNU Emacs 27.1 (build 2, x86_64-pc-linux-gnu, GTK+ Version 3.24.8).

Steps to reproduce:

1. emacs -Q &
2. C-x C-e on each line of:
   ┌────
   │ (package-initialize)  
   │ (setq TeX-auto-save t)
   │ (setq TeX-parse-self t)
   └────
3. Open `.tex` file.

The *Message* buffer displays:

  ┌────
  │ For information about GNU Emacs and the GNU system, type C-h C-a.
  │ Mark set [4 times]
  │ nil
  │ Package cl is deprecated
  │ t [2 times]
  │ Applying style hooks...
  │ Loading /home/bitouze/latex/divers/auto/test.el (source)...done
  │ Loading /home/bitouze/.emacs.d/elpa/auctex-13.0.0/style/beamer.elc...done
  │ Loading /home/bitouze/.emacs.d/elpa/auctex-13.0.0/style/amsmath.elc...done
  │ Loading /home/bitouze/.emacs.d/elpa/auctex-13.0.0/style/amstext.elc...done
  │ Loading /home/bitouze/.emacs.d/elpa/auctex-13.0.0/style/amsbsy.elc...done
  │ Loading /home/bitouze/.emacs.d/elpa/auctex-13.0.0/style/amsopn.elc...done
  │ Loading /home/bitouze/.emacs.d/elpa/auctex-13.0.0/style/amssymb.elc...done
  │ Loading /home/bitouze/.emacs.d/elpa/auctex-13.0.0/style/amsfonts.elc...done
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/home/bitouze/.emacs.d/elpa/auctex-13.0.0/style/filecontents.elc...done
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/home/bitouze/.emacs.d/elpa/auctex-13.0.0/style/subcaption.elc...done
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/home/bitouze/.emacs.d/elpa/auctex-13.0.0/style/transparent.elc...done
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/home/bitouze/.emacs.d/elpa/auctex-13.0.0/style/polyglossia.elc...done
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  │ Loading /home/bitouze/.emacs.d/elpa/auctex-13.0.0/style/fancyvrb.elc...
  │ Sorting length...done
  │ Removing duplicates...done
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  │ Sorting pagestyle...done
  │ Removing duplicates...done
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  │ TeX-auto-parse-region: Wrong type argument: stringp, nil
  └────

Thanks!   
-- 
Denis