bug#44647: 27.1.50; `bibtex-contline-indentation' doesn't work as file local variable

["Roland Winkler" <winkler@gnu.org>]

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On Sat Nov 14 2020 Teemu Likonen wrote:
> This can be fixed by locally let-binding fill-prefix every time in
> the relevant filling function. Patch for that is attached.

Your patch implies that the buffer-local value of fill-prefix is not
what it should be (say, if any other command wants to use it).

How about the rather different patch attached below, partly inspired
by the related comment

https://debbugs.gnu.org/cgi/bugreport.cgi?bug=21764#15

which had somehow escaped my attention.  The issues mentioned in
this comment should likewise be fixed by the attached patch.


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--- bibtex.el~	2020-11-15 21:13:56.440216563 -0600
+++ bibtex.el	2020-11-15 21:28:47.313180062 -0600
@@ -890,7 +890,8 @@
 (defcustom bibtex-comment-start "@Comment"
   "String starting a BibTeX comment."
   :group 'bibtex
-  :type 'string)
+  :type 'string
+  :safe #'stringp)
 
 (defcustom bibtex-add-entry-hook nil
   "List of functions to call when BibTeX entry has been inserted."
@@ -1219,7 +1220,8 @@
   "Offset for BibTeX entries.
 Added to the value of all other variables which determine columns."
   :group 'bibtex
-  :type 'integer)
+  :type 'integer
+  :safe #'integerp)
 
 (defcustom bibtex-field-indentation 2
   "Starting column for the name part in BibTeX fields."
@@ -1232,13 +1234,15 @@
   "Starting column for the text part in BibTeX fields.
 Should be equal to the space needed for the longest name part."
   :group 'bibtex
-  :type 'integer)
+  :type 'integer
+  :safe #'integerp)
 
 (defcustom bibtex-contline-indentation
   (+ bibtex-text-indentation 1)
   "Starting column for continuation lines of BibTeX fields."
   :group 'bibtex
-  :type 'integer)
+  :type 'integer
+  :safe #'integerp)
 
 (defcustom bibtex-align-at-equal-sign nil
   "If non-nil, align fields at equal sign instead of field text.
@@ -2941,7 +2945,7 @@
                                          (1+ (match-beginning 3)) (1- (match-end 3)))))
                                (unless (assoc key crossref-keys)
                                  (push (list key) crossref-keys))))
-                            ;; We have probably have a non-bibtex file.
+                            ;; We probably have a non-bibtex file.
                             ((not (match-beginning bibtex-type-in-head))
                              (throw 'userkey nil))
                             ;; only keys of known entries
@@ -3435,15 +3439,10 @@
                                    bibtex-parse-keys-timeout t
                                    'bibtex-parse-buffers-stealthily)))
   (set (make-local-variable 'paragraph-start) "[ \f\n\t]*$")
-  (set (make-local-variable 'comment-start) bibtex-comment-start)
-  (set (make-local-variable 'comment-start-skip)
-       (concat (regexp-quote bibtex-comment-start) "\\>[ \t]*"))
   (set (make-local-variable 'comment-column) 0)
   (set (make-local-variable 'defun-prompt-regexp) "^[ \t]*@[[:alnum:]]+[ \t]*")
   (set (make-local-variable 'outline-regexp) "[ \t]*@")
   (set (make-local-variable 'fill-paragraph-function) #'bibtex-fill-field)
-  (set (make-local-variable 'fill-prefix)
-       (make-string (+ bibtex-entry-offset bibtex-contline-indentation) ?\s))
   (set (make-local-variable 'font-lock-defaults)
        '(bibtex-font-lock-keywords
          nil t ((?$ . "\"")
@@ -3462,9 +3461,18 @@
   (set (make-local-variable 'syntax-propertize-function)
        (syntax-propertize-via-font-lock
         bibtex-font-lock-syntactic-keywords))
-  (bibtex-set-dialect nil t)
-  ;; Allow `bibtex-dialect' as a file-local variable.
-  (add-hook 'hack-local-variables-hook #'bibtex-set-dialect nil t))
+  (let ((fun (lambda ()
+               (bibtex-set-dialect)
+               (set (make-local-variable 'comment-start) bibtex-comment-start)
+               (set (make-local-variable 'comment-start-skip)
+                    (concat (regexp-quote bibtex-comment-start) "\\>[ \t]*"))
+               (set (make-local-variable 'fill-prefix)
+                    (make-string (+ bibtex-entry-offset
+                                    bibtex-contline-indentation)
+                                 ?\s)))))
+    (if buffer-file-name
+        (add-hook 'hack-local-variables-hook fun nil t)
+      (funcall fun))))
 
 (defun bibtex-entry-alist (dialect)
   "Return entry-alist for DIALECT."