How to show a tooltip for the mode-line that displays the full buffer name

Question

Is there a way to show a tooltip that contains the full buffer name when I hover over the buffer name part of the mode line? I'd like to quickly check the full buffer name when I have a narrow frame that only shows the beginning of the buffer name in the mode line. Currently it only displays a tooltip that says "Buffer name".

Answer 1

This should do it.

(setq-default mode-line-buffer-identification
              (list (propertize
                     "%12b"
                     'face 'mode-line-buffer-id
                     'help-echo
                     '(format "%s\nmouse-1: Previous buffer\nmouse-3: Next buffer"
                       (buffer-name))
                     'mouse-face 'mode-line-highlight
                     'local-map mode-line-buffer-identification-keymap)))

I grepped the Emacs Lisp sources for "Buffer name" and found that that text was set up in the mode-line in bindings.el. I just changed the help-echo part, to use the full (buffer-name).