Use `locate-dominating-file’ rather than reimplementing it.

[pelican-mode.git] / pelican-mode.el

diff --git a/pelican-mode.el b/pelican-mode.el
index 4c3428a..47153f8 100644 (file)
--- a/pelican-mode.el
+++ b/pelican-mode.el
@@ -20,11 +20,22 @@
 ;; You should have received a copy of the GNU General Public License
 ;; along with this program.  If not, see <http://www.gnu.org/licenses/>.
 
+
 ;;; Commentary:
 ;;
-;; Probably, this doesn't handle a lot of error cases.  I also never
-;; tested it on networked drives and the lookup for pelicanconf.py
-;; might slow it down considerably.
+;; pelican-mode is an Emacs minor mode for editing pages and posts in
+;; Pelican (URL http://getpelican.com/) sites.
+;;
+;; It's intended to be used alongside `markdown-mode' or `rst-mode'.
+;; It also assumes you've set up Pelican with ``pelican-quickstart''
+;; or something like it.  In particular it assumes:
+;;
+;;  * The existence of ``pelicanconf.py'' and ``Makefile'' in some
+;;    ancestor directory.
+;;  * The first component of the path (e.g. ``content'') after that
+;;    ancestor is irrelevant.
+;;  * If the next component is ``pages'', that indicates a page
+;;    rather than an article.
 
 
 ;;; Code:
@@ -54,6 +65,16 @@ about metadata fields and special values."
   :group 'pelican
   :type '(plist))
 
+(defcustom pelican-mode-set-field-alist
+  '((markdown-mode . pelican-mode-set-field-markdown-mode)
+    (rst-mode . pelican-mode-set-field-rst-mode))
+  "Functions to handle setting metadata, based on major mode.
+
+This association list maps modes to functions that take two
+arguments, field and value strings."
+  :group 'pelican
+  :type '(alist :key-type function :value-type function))
+
 (defun pelican-mode-timestamp (&optional time)
   "Generate a pelican-mode-compatible timestamp for TIME."
   (format-time-string "%Y-%m-%d %H:%M" time))
@@ -86,7 +107,7 @@ about metadata fields and special values."
        #'pelican-mode-insert-page-header
      #'pelican-mode-insert-draft-article-header)))
 
-(defun pelican-mode-set-field/rst-mode (field value)
+(defun pelican-mode-set-field-rst-mode (field value)
   "Set reStructuredText metadata FIELD to VALUE."
   (setq field (downcase field))
   (if (equal field "title")
@@ -101,18 +122,20 @@ about metadata fields and special values."
       (if (re-search-forward (format "^:%s:.*\n" (regexp-quote field)) nil t)
           (replace-match (or text ""))
         (when text
-          (re-search-forward "^$")
-          (replace-match text))))))
+          (if (re-search-forward "^$" nil t)
+              (replace-match text)
+            (insert text)))))))
 
-(defun pelican-mode-set-field/markdown-mode (field value)
+(defun pelican-mode-set-field-markdown-mode (field value)
   "Set Markdown metadata FIELD to VALUE."
   (setq field (capitalize field))
   (let ((text (when value (format "%s: %s\n" field value))))
     (if (re-search-forward (format "^%s:.*\n" (regexp-quote field)) nil t)
         (replace-match text)
       (when value
-        (re-search-forward "^$")
-        (replace-match  text)))))
+        (if (re-search-forward "^$" nil t)
+            (replace-match text)
+          (insert text))))))
 
 (defun pelican-mode-set-field (field value)
   "Set FIELD to VALUE.
@@ -137,13 +160,13 @@ the unquoted printed representation of it is used:
                 (_ value)))
   (when (symbolp field)
     (setq field (string-remove-prefix ":" (symbol-name field))))
-  (save-excursion
-    (goto-char 0)
-    (cond ((derived-mode-p 'markdown-mode)
-           (pelican-mode-set-field/markdown-mode field value))
-          ((derived-mode-p 'rst-mode)
-           (pelican-mode-set-field/rst-mode field value))
-          (t (error "Unsupported major mode %S" major-mode)))))
+  (let ((set-field
+         (assoc-default nil pelican-mode-set-field-alist #'derived-mode-p)))
+    (unless set-field
+      (error "Unsupported major mode %S" major-mode))
+    (save-excursion
+      (goto-char 0)
+      (funcall set-field field value))))
 
 (defun pelican-mode-remove-field (field)
   "Remove FIELD."
@@ -181,25 +204,12 @@ the unquoted printed representation of it is used:
              (components (if (string= "pages" (car components))
                              (cdr components) components)))
         (mapconcat 'identity components "/"))
-    (format "%s/%s"
-            (file-name-nondirectory
-             (directory-file-name
-              (file-name-directory file-name)))
-            (file-name-base file-name))))
-
-(defun pelican-mode-find-in-parents (file-name)
-  "Find FILE-NAME in the default directory or one of its parents, or nil."
-  (let* ((parent (expand-file-name default-directory)))
-    (while (and (not (file-readable-p (concat parent file-name)))
-                (not (string= parent (directory-file-name parent))))
-      (setq parent (file-name-directory (directory-file-name parent))))
-    (let ((found (concat parent file-name)))
-      (if (file-readable-p found) found nil))))
+    (when-let (file-name (file-name-sans-extension buffer-file-name))
+      (file-name-base file-name))))
 
 (defun pelican-mode-find-root ()
   "Return the root of the buffer's Pelican site, or nil."
-  (when-let (conf (pelican-mode-find-in-parents "pelicanconf.py"))
-    (file-name-directory conf)))
+  (locate-dominating-file default-directory "pelicanconf.py"))
 
 (defun pelican-make (target)
   "Execute TARGET in a Makefile at the root of the site."
@@ -207,7 +217,7 @@ the unquoted printed representation of it is used:
   (if-let (default-directory (pelican-mode-find-root))
       (compilation-start (format "make %s" target)
                          nil (lambda (_) "*pelican*"))
-    (user-error "This doesn't look like a Pelican site")))
+    (user-error "No Pelican site root could be found")))
 
 (defun pelican-make-html ()
   "Generate HTML via a Makefile at the root of the site."