* lisp/linum.el (linum--face-height): New function.

(linum-update-window): Use it to adjust margin to linum's width.

Fixes: debbugs:17813

2 files changed, 12 insertions, 0 deletions

diff --git a/lisp/ChangeLog b/lisp/ChangeLog
index 6dbd14f6a48..0158ce91aea 100644
--- a/lisp/ChangeLog
+++ b/lisp/ChangeLog
@@ -1,5 +1,8 @@
 2014-07-08  Stefan Monnier  <monnier@iro.umontreal.ca>
 
+	* linum.el (linum--face-height): New function (bug#17813).
+	(linum-update-window): Use it to adjust margin to linum's width.
+
 	* leim/quail/sisheng.el (sisheng-list): Don't bother with-case-table.
 	* eshell/em-smart.el (eshell-smart-scroll-window): Use
 	with-selected-window.
diff --git a/lisp/linum.el b/lisp/linum.el
index bbf7ebec399..b13bd8dbbb6 100644
--- a/lisp/linum.el
+++ b/lisp/linum.el
@@ -138,6 +138,9 @@ Linum mode is a buffer-local minor mode."
       (mapc #'delete-overlay linum-available)
       (setq linum-available nil))))
 
+(defun linum--face-height (face)
+  (aref (font-info (face-font face)) 2))
+
 (defun linum-update-window (win)
   "Update line numbers for the portion visible in window WIN."
   (goto-char (window-start win))
@@ -178,6 +181,12 @@ Linum mode is a buffer-local minor mode."
       (let ((inhibit-point-motion-hooks t))
         (forward-line))
       (setq line (1+ line)))
+    (when (display-graphic-p)
+      (setq width (ceiling
+                   ;; We'd really want to check the widths rather than the
+                   ;; heights, but it's a start.
+                   (/ (* width 1.0 (linum--face-height 'linum))
+                      (frame-char-height)))))
     (set-window-margins win width (cdr (window-margins win)))))
 
 (defun linum-after-change (beg end _len)