Michael Albinus <michael.albinus@gmx.de> writes:

> "Basil L. Contovounesios" <contovob@tcd.ie> writes:
>
>> What is the best way to determine whether notifications are supported by
>> the current Emacs instance?  I skimmed through (info "(dbus) Top") and
>> (info "(elisp) Desktop Notifications"), as well as through the syms of
>> dbusbind.c, dbus.el, and notifications.el, but did not find any clear
>> answers.
>
> (featurep 'dbusbind)
>
> checks, whether Emacs is configured to use D-Bus. This does not
> necessarily tells you that notifications are supported, but it gives you
> a strong indication for this.

Thanks, I somehow missed this check littered all over the place.

> You could also wrap the call of notifications-notify by dbus-ignore-errors.
>
> A better check would be to ping notifications-service, but this should
> be done inside notifications.el, if needed.

Indeed, these two alternatives sound like the responsibility of
notifications.el, not its users.  The patch I proposed does not change
existing behaviour of gnus-notifications.el in this regard.

However, I'm not sure what the best thing to do in notifications-notify
is.  So far, it has returned nil for any type of error (unless
debug-on-error is non-nil), thanks to its use of with-demoted-errors.

Would it be too backward-incompatible to change this to
dbus-ignore-errors or pinging notifications-service, as you say?

If so, how's the following docfix instead?