Don't use insert behind hook. It often get ignored. See issue 3

diff --git a/yasnippet.el b/yasnippet.el
index 15ef212fa34db6e35e9c87f1a52f650ebea8fdd8..966530892b37099994fc2c5de014653657741a9c 100644 (file)
--- a/yasnippet.el
+++ b/yasnippet.el
@@ -118,9 +118,9 @@ mode will be listed under the menu \"yasnippet\".")
 (defvar yas/overlay-insert-in-front-hooks
   (list 'yas/overlay-insert-in-front-hook)
   "The list of hooks of the overlay inserted in front event.")
-(defvar yas/overlay-insert-behind-hooks
-  (list 'yas/overlay-insert-behind-hook)
-  "The list of hooks of the overlay inserted behind event.")
+(defvar yas/keymap-overlay-modification-hooks
+  (list 'yas/overlay-maybe-insert-behind-hook)
+  "The list of hooks of the big keymap overlay modification event.")
 
 
 ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
@@ -299,14 +299,22 @@ the template of a snippet in the current snippet-table."
            (goto-char end)
            (delete-char (- (overlay-end overlay) end)))))
      (yas/synchronize-fields field-group))))
-(defun yas/overlay-insert-behind-hook (overlay after? beg end &optional length)
-  "Hook for snippet overlay when text is inserted just behind a snippet field."
+(defun yas/overlay-maybe-insert-behind-hook (overlay after? beg end &optional length)
+  "Insert behind hook sometimes doesn't get called. I don't know why.
+So I add modification hook in the big overlay and try to detect `insert-behind'
+event manually."
   (when (and after?
-            (null (yas/current-snippet-overlay beg))) ; not inside another field
-    (move-overlay overlay
-                 (overlay-start overlay)
-                 end)
-    (yas/synchronize-fields (overlay-get overlay 'yas/group))))
+            (= length 0)
+            (> end beg)
+            (null (yas/current-snippet-overlay beg))
+            (not (bobp)))
+    (let ((field-overlay (yas/current-snippet-overlay (1- beg))))
+      (when (and field-overlay
+                (= beg (overlay-end field-overlay)))
+       (move-overlay field-overlay
+                     (overlay-start field-overlay)
+                     end)
+       (yas/synchronize-fields (overlay-get field-overlay 'yas/group))))))
 
 (defun yas/undo-expand-snippet (start end key snippet)
   "Undo a snippet expansion. Delete the overlays. This undo can't be
@@ -412,6 +420,12 @@ will be deleted before inserting template."
                                     nil
                                     nil
                                     t)))
+         (overlay-put overlay 
+                      'modification-hooks
+                      yas/keymap-overlay-modification-hooks)
+         (overlay-put overlay 
+                      'insert-behind-hooks
+                      yas/keymap-overlay-modification-hooks)
          (overlay-put overlay 'keymap yas/keymap)
          (overlay-put overlay 'yas/snippet-reference snippet)
          (setf (yas/snippet-overlay snippet) overlay))
@@ -444,7 +458,6 @@ will be deleted before inserting template."
            (overlay-put overlay 'yas/modified? nil)
            (overlay-put overlay 'modification-hooks yas/overlay-modification-hooks)
            (overlay-put overlay 'insert-in-front-hooks yas/overlay-insert-in-front-hooks)
-           (overlay-put overlay 'insert-behind-hooks yas/overlay-insert-behind-hooks)
            (dolist (field (yas/group-fields group))
              (overlay-put (yas/field-overlay field)
                           'face