Uniquify keys

Add option to automatically create unique keys when a key is added that already
exists.

diff --git a/src/ebib.el b/src/ebib.el
index a4bc450..e871782 100644 (file)
--- a/src/ebib.el
+++ b/src/ebib.el
@@ -82,6 +82,15 @@ Only takes effect if EBIB-LAYOUT is set to CUSTOM."
   :group 'ebib
   :type '(repeat (symbol :tag "Index Field")))
 
+(defcustom ebib-uniquify-keys nil
+  "*Create unique keys.
+If set, Ebib will not complain about duplicate keys but will
+instead create a unique key by adding an identifier to it.
+Identifiers are created from consecutive letters of the
+alphabet, starting with `b'."
+  :group 'ebib
+  :type 'boolean)
+
 (defcustom ebib-autogenerate-keys nil
   "*If set, Ebib generates key automatically.
 Uses the function BIBTEX-GENERATE-AUTOKEY, see there for
@@ -1897,28 +1906,39 @@ buffer if Ebib is not occupying the entire frame."
                          (read-string "New entry key: ")))
         (progn
           (if (member entry-key (edb-keys-list ebib-cur-db))
-              (error "Key already exists")
-            (set-buffer ebib-index-buffer)
-            (sort-in-buffer (1+ (edb-n-entries ebib-cur-db)) entry-key)
-            ;; we create the hash table *before* the call to
-            ;; ebib-display-entry, because that function refers to the
-            ;; hash table if ebib-index-display-fields is set.
-            (let ((fields (make-hash-table)))
-              (puthash 'type* ebib-default-type fields)
-              (ebib-insert-entry entry-key fields ebib-cur-db t t))
-            (with-buffer-writable
-              (ebib-display-entry entry-key))
-            (forward-line -1) ; move one line up to position the cursor on the new entry.
-            (ebib-set-index-highlight)
-            (setf (edb-cur-entry ebib-cur-db) (member entry-key (edb-keys-list ebib-cur-db)))
-            (ebib-fill-entry-buffer)
-            (ebib-edit-entry)
-            (ebib-set-modified t)))))
+              (if ebib-uniquify-keys
+                  (setq entry-key (ebib-uniquify-key entry-key))
+                (error "Key already exists")))
+          (set-buffer ebib-index-buffer)
+          (sort-in-buffer (1+ (edb-n-entries ebib-cur-db)) entry-key)
+          ;; we create the hash table *before* the call to
+          ;; ebib-display-entry, because that function refers to the
+          ;; hash table if ebib-index-display-fields is set.
+          (let ((fields (make-hash-table)))
+            (puthash 'type* ebib-default-type fields)
+            (ebib-insert-entry entry-key fields ebib-cur-db t t))
+          (with-buffer-writable
+            (ebib-display-entry entry-key))
+          (forward-line -1) ; move one line up to position the cursor on the new entry.
+          (ebib-set-index-highlight)
+          (setf (edb-cur-entry ebib-cur-db) (member entry-key (edb-keys-list ebib-cur-db)))
+          (ebib-fill-entry-buffer)
+          (ebib-edit-entry)
+          (ebib-set-modified t))))
     ((no-database)
      (error "No database open. Use `o' to open a database first"))
     ((default)
      (beep))))
 
+(defun ebib-uniquify-key (key)
+  "Creates a unique key from KEY."
+  (let* ((suffix ?b)
+        (unique-key (concat key (list suffix))))
+    (while (member unique-key (edb-keys-list ebib-cur-db))
+      (setq suffix (1+ suffix))
+      (setq unique-key (concat key (list suffix))))
+    unique-key))
+
 (defun ebib-generate-autokey ()
   "Automatically generate a key for the current entry.
 This function uses the function BIBTEX-GENERATE-AUTOKEY to
@@ -2029,22 +2049,24 @@ generate the key, see that function's documentation for details."
 (defun ebib-update-keyname (new-key)
   "Changes the key of the current BibTeX entry to NEW-KEY."
   (if (member new-key (edb-keys-list ebib-cur-db))
-      (error (format "Key `%s' already exists" new-key))
-    (let ((cur-key (ebib-cur-entry-key)))
-      (unless (string= cur-key new-key)
-       (let ((fields (ebib-retrieve-entry cur-key ebib-cur-db))
-             (marked (member cur-key (edb-marked-entries ebib-cur-db))))
-         (ebib-remove-entry-from-db cur-key ebib-cur-db)
-         (ebib-remove-key-from-buffer cur-key)
-         (ebib-insert-entry new-key fields ebib-cur-db t nil)
-         (setf (edb-cur-entry ebib-cur-db) (member new-key (edb-keys-list ebib-cur-db)))
-         (sort-in-buffer (edb-n-entries ebib-cur-db) new-key)
-         (with-buffer-writable
-           (ebib-display-entry new-key))
-         (forward-line -1) ; move one line up to position the cursor on the new entry.
-         (ebib-set-index-highlight)
-         (ebib-set-modified t)
-         (when marked (ebib-mark-entry)))))))
+      (if ebib-uniquify-keys
+         (setq new-key (ebib-uniquify-key new-key))
+       (error (format "Key `%s' already exists" new-key))))
+  (let ((cur-key (ebib-cur-entry-key)))
+    (unless (string= cur-key new-key)
+      (let ((fields (ebib-retrieve-entry cur-key ebib-cur-db))
+           (marked (member cur-key (edb-marked-entries ebib-cur-db))))
+       (ebib-remove-entry-from-db cur-key ebib-cur-db)
+       (ebib-remove-key-from-buffer cur-key)
+       (ebib-insert-entry new-key fields ebib-cur-db t nil)
+       (setf (edb-cur-entry ebib-cur-db) (member new-key (edb-keys-list ebib-cur-db)))
+       (sort-in-buffer (edb-n-entries ebib-cur-db) new-key)
+       (with-buffer-writable
+         (ebib-display-entry new-key))
+       (forward-line -1) ; move one line up to position the cursor on the new entry.
+       (ebib-set-index-highlight)
+       (ebib-set-modified t)
+       (when marked (ebib-mark-entry))))))
 
 (defun ebib-mark-entry ()
   "Marks or unmarks the current entry."