Each keybinding in dfhack.init-example should be mentioned in the documentation for the relevant command, including the context/s the binding is limited to. Travis should test that (a) each keybinding is documented, and (b) that each documented keybinding exists.

It would be fairly easy to enforce an ugly and labor-intensive version via text-matching. However I'd prefer to use a custom Sphinx directive (or role), which would enable some nice formatting and automatically stay up-to-date with the init file.