bibtex-string-file-path and bibtex-file-path are lists of directories

* lisp/textmodes/bibtex.el (bibtex-string-file-path, bibtex-file-path):
These user options are now lists of directories.  For backward compatibility,
the old, obsolete format is still supported.
(bibtex-string-files-init, bibtex-initialize): Change accordingly.
Use file-name-extension and file-name-with-extension.
* etc/NEWS: Entry for new format of bibtex-string-file-path and
bibtex-file-path.

2 files changed, 69 insertions, 46 deletions

diff --git a/etc/NEWS b/etc/NEWS
index d017c872fa3..62b90aa11aa 100644
--- a/etc/NEWS
+++ b/etc/NEWS
@@ -826,6 +826,11 @@ Use 'bibtex-aux-opt-alist' instead.
 *** New user option 'bibtex-entry-ask-for-key'.
 When enabled, 'bibtex-entry' asks for a key.
 
+---
+*** 'bibtex-string-file-path' and 'bibtex-file-path' are lists of directories.
+For backward compatibility, considered obsolete, these user options
+may still be strings with colon separated lists of directories.
+
 ** Midnight mode
 
 ---
diff --git a/lisp/textmodes/bibtex.el b/lisp/textmodes/bibtex.el
index 601331cbce2..83d8f2e6e70 100644
--- a/lisp/textmodes/bibtex.el
+++ b/lisp/textmodes/bibtex.el
@@ -1095,13 +1095,16 @@ to the directories specified in `bibtex-string-file-path'."
   :group 'bibtex
   :type '(repeat file))
 
-(defcustom bibtex-string-file-path (getenv "BIBINPUTS")
-  "Colon-separated list of paths to search for `bibtex-string-files'.
-Initialized from the BIBINPUTS environment variable."
+(defcustom bibtex-string-file-path (split-string (getenv "BIBINPUTS") ":+" t)
+  "List of directories to search for `bibtex-string-files'.
+By default, initialized from the BIBINPUTS environment variable.
+For backward compatibility, considered obsolete, it may also be
+a single string with a colon separated list of directories."
   :group 'bibtex
-  :version "27.1"
-  :type '(choice string
-                 (const :tag "Not Set" nil)))
+  :version "31.1"
+  :type '(choice (repeat directory)
+                 (string :tag "String (obsolete)")
+                 (const :tag "Not set" nil)))
 
 (defcustom bibtex-files nil
   "List of BibTeX files that are searched for entry keys.
@@ -1114,13 +1117,16 @@ See also `bibtex-search-entry-globally'."
   :type '(repeat (choice (const :tag "bibtex-file-path" bibtex-file-path)
                          directory file)))
 
-(defcustom bibtex-file-path (getenv "BIBINPUTS")
-  "Colon separated list of paths to search for `bibtex-files'.
-Initialized from the BIBINPUTS environment variable."
+(defcustom bibtex-file-path (split-string (getenv "BIBINPUTS") ":+" t)
+  "List of directories to search for `bibtex-files'.
+By default, initialized from the BIBINPUTS environment variable.
+For backward compatibility, considered obsolete, it may also be
+a single string with a colon separated list of directories."
   :group 'bibtex
-  :version "27.1"
-  :type '(choice string
-                 (const :tag "Not Set" nil)))
+  :version "31.1"
+  :type '(choice (repeat directory)
+                 (string :tag "String (obsolete)")
+                 (const :tag "Not set" nil)))
 
 (defcustom bibtex-search-entry-globally nil
   "If non-nil, interactive calls of `bibtex-search-entry' search globally.
@@ -3195,30 +3201,35 @@ Return alist of strings if parsing was completed, `aborted' otherwise."
 
 (defun bibtex-string-files-init ()
   "Return initialization for `bibtex-strings'.
-Use `bibtex-predefined-strings' and BibTeX files `bibtex-string-files'."
-  (save-match-data
-    (let ((dirlist (split-string (or bibtex-string-file-path default-directory)
-                                 ":+"))
-          (case-fold-search)
-          string-files fullfilename compl bounds found)
-      ;; collect absolute file names of valid string files
-      (dolist (filename bibtex-string-files)
-        (unless (string-match "\\.bib\\'" filename)
-          (setq filename (concat filename ".bib")))
-        ;; test filenames
-        (if (file-name-absolute-p filename)
-            (if (file-readable-p filename)
-                (push filename string-files)
-              (user-error "BibTeX strings file %s not found" filename))
+Use `bibtex-predefined-strings' and BibTeX files `bibtex-string-files'
+with `bibtex-string-file-path'."
+  (let ((dirlist
+         (or (if (stringp bibtex-string-file-path) ; obsolete format
+                 (save-match-data
+                   (split-string bibtex-string-file-path ":+" t))
+               bibtex-string-file-path)
+             (list default-directory)))
+        string-files)
+    ;; collect absolute file names of valid string files
+    (dolist (filename bibtex-string-files)
+      (unless (string= "bib" (file-name-extension filename))
+        (setq filename (file-name-with-extension filename "bib")))
+      ;; test filenames
+      (if (file-name-absolute-p filename)
+          (if (file-readable-p filename)
+              (push filename string-files)
+            (user-error "BibTeX strings file %s not found" filename))
+        (let (found)
           (dolist (dir dirlist)
-            (when (file-readable-p
-                   (setq fullfilename (expand-file-name filename dir)))
-              (push fullfilename string-files)
-              (setq found t)))
+            ;; filename may exist in multiple directories
+            (let ((fullfilename (expand-file-name filename dir)))
+              (when (file-readable-p fullfilename)
+                (push fullfilename string-files)
+                (setq found t))))
           (unless found
-            (user-error "File %s not in paths defined via bibtex-string-file-path"
-                        filename))))
-      ;; parse string files
+            (user-error "File %s not in bibtex-string-file-path" filename)))))
+    ;; parse string files
+    (let (compl bounds)
       (dolist (filename string-files)
         (with-temp-buffer
           (insert-file-contents filename)
@@ -3270,9 +3281,20 @@ already set.  If SELECT is non-nil interactively select a BibTeX buffer.
 When called interactively, FORCE is t, CURRENT is t if current buffer
 visits a file using `bibtex-mode', and SELECT is t if current buffer
 does not use `bibtex-mode'."
-  (interactive (list (eq major-mode 'bibtex-mode) t
+  ;; Interactively, exclude current buffer if it does not visit a file
+  ;; using `bibtex-mode'.  This way, we exclude BibTeX buffers such as
+  ;; `bibtex-search-buffer' that are not visiting a BibTeX file.
+  ;; Also, calling `bibtex-initialize' gives meaningful results for any
+  ;; current buffer.
+  (interactive (list (eq major-mode 'bibtex-mode)
+                     (and buffer-file-name (eq major-mode 'bibtex-mode))
                      (not (eq major-mode 'bibtex-mode))))
-  (let ((file-path (split-string (or bibtex-file-path default-directory) ":+"))
+  (let ((file-path
+         (or (if (stringp bibtex-file-path) ; obsolete format
+                 (save-match-data
+                   (split-string bibtex-file-path ":+" t))
+               bibtex-file-path)
+             (list default-directory)))
         file-list dir-list buffer-list)
     ;; generate list of BibTeX files
     (dolist (file bibtex-files)
@@ -3280,20 +3302,20 @@ does not use `bibtex-mode'."
              (setq dir-list (append dir-list file-path)))
             ((file-accessible-directory-p file)
              (push file dir-list))
-            ((progn (unless (string-match "\\.bib\\'" file)
-                      (setq file (concat file ".bib")))
+            ((progn (unless (string= "bib" (file-name-extension file))
+                      (setq file (file-name-with-extension file "bib")))
                     (file-name-absolute-p file))
              (push file file-list))
             (t
              (let (expanded-file-name found)
                (dolist (dir file-path)
+                 ;; filename may exist in multiple directories
                  (when (file-readable-p
                         (setq expanded-file-name (expand-file-name file dir)))
                    (push expanded-file-name file-list)
                    (setq found t)))
                (unless found
-                 (user-error "File `%s' not in paths defined via bibtex-file-path"
-                             file))))))
+                 (user-error "File `%s' not in bibtex-file-path" file))))))
     (dolist (file file-list)
       (unless (file-readable-p file)
         (user-error "BibTeX file `%s' not found" file)))
@@ -3307,12 +3329,6 @@ does not use `bibtex-mode'."
       (if (file-readable-p file)
         (push (find-file-noselect file) buffer-list)))
     ;; Include current buffer iff we want it.
-    ;; Exclude current buffer if it does not visit a file using `bibtex-mode'.
-    ;; This way we exclude BibTeX buffers such as `bibtex-search-buffer'
-    ;; that are not visiting a BibTeX file.  Also, calling `bibtex-initialize'
-    ;; gives meaningful results for any current buffer.
-    (unless (and current (eq major-mode 'bibtex-mode) buffer-file-name)
-      (setq current nil))
     (cond ((and current (not (memq (current-buffer) buffer-list)))
            (push (current-buffer) buffer-list))
           ((and (not current) (memq (current-buffer) buffer-list))
@@ -3321,6 +3337,8 @@ does not use `bibtex-mode'."
     (let (string-init)
       (dolist (buffer buffer-list)
         (with-current-buffer buffer
+          ;; `bibtex-reference-keys' and `bibtex-strings' are buffer-local
+          ;; lazy completion tables.  So we only initiate them as needed.
           (if (or force (functionp bibtex-reference-keys))
               (bibtex-parse-keys))
           (when (or force (functionp bibtex-strings))