bug#19395: 25.0.50; Setting left fringe to 0 messes up window-width

[martin rudalics <rudalics@gmx.at>]

 > Given the changes I pushed in commit b197822, you will no longer need
 > all this complexity.  Just
 >
 >     (aref (font-info (face-font 'default)) 11)
 >
 > (For bullet-proof code, check that this is not zero, and if it is, use
 > the 10th member instead; see the docs.)

Very good.  IIUC this means that I could use something like

(defun window-char-width (&optional window)
   "Return default character width for WINDOW.
WINDOW must be a live window and defaults to the selected one."
   (setq window (window-normalize-window window t))
   (with-current-buffer (window-buffer window)
     (let* ((info (font-info (face-font 'default)))
	   (width (aref info 11)))
       (if (> width 0)
	  width
	(aref info 10)))))

(defun window-char-height (&optional window)
   "Return default character height for WINDOW.
WINDOW must be a live window and defaults to the selected one."
   (setq window (window-normalize-window window t))
   (with-current-buffer (window-buffer window)
     (aref (font-info (face-font 'default)) 3)))

in window.el.  If that is the case, then the doc of `font-info' should
be somehow amended.  It currently says

Return information about a font named NAME on frame FRAME.

and nowhere mentions which buffer must be current or maybe even which
window must be selected.  I'm a bit too lazy to look into this myself.

Thanks a lot for this, martin