Subject: Re: bug#23933: 25.1.50; Run a buffer-local hook with mapc

From: [email-masked]
Date: Sun, 10 Jul 2016 13:12:12 -0400

Stefan Monnier <[email-masked]> writes:

>>> after-quit-hook-internal is a variable, not a hook.
>> Then how come it includes t in its value?
>
> [...] Maybe because the value of that var was copied from the value
> of an actual hook.

Yes:

(defun ediff-really-quit (reverse-default-keep-variants)
  ...
   (let (...
         (after-quit-hook-internal ediff-after-quit-hook-internal)

And as mentioned in the patch, ediff-filegroup-action calls add-hook
with non-nil LOCAL on ediff-after-quit-hook-internal.

-  (mapc #'funcall after-quit-hook-internal)
+  ;; after-quit-hook-internal is buffer-local; see `ediff-filegroup-action'.
+  (mapc (lambda (f) (or (eq f t) (funcall f))) after-quit-hook-internal)
   ))