[Pkg-utopia-maintainers] Bug#965324: python3-dbus: Missing dependency on the dbus-X11 package

[smcv at debian.org]

Control: retitle -1 guake: missing dependency on default-dbus-session-bus|dbus-session-bus
Control: reassign -1 guake 3.4.0-1

On Sun, 19 Jul 2020 at 16:49:47 +0200, Sergiy Kolesnikov wrote:
> while running the Guake terminal emulator I encountered the following
> exception:
> 
> dbus.exceptions.DBusException: org.freedesktop.DBus.Error.Spawn.ExecFailed:
> /usr/bin/dbus-launc
> h terminated abnormally without any error message
> 
> By installing the dbus-X11 package the problem was resolved and Guake ran
> successfully.
> 
> Since the exception was thrown in the dbus Python package, it looks like it
> should depend on dbus-X11.

python3-dbus can be used for several purposes, not all of which need a
D-Bus session bus in your desktop environment. If an application requires
the D-Bus session bus, it is up to that application to depend on it.

There are multiple ways to get a session bus, so applications that require
a D-Bus session bus and cannot work without it should usually depend on
the virtual packages "default-dbus-session-bus | dbus-session-bus". For
example, gnome-terminal does this correctly. dbus-session-bus is currently
provided by dbus-user-session (only implemented on the Linux kernel,
where it is the default) and by dbus-x11 (the default on non-Linux ports,
and also available on Linux, mainly for systems that do not boot using
systemd). If both implementations are installed, dbus-user-session
is preferred.

The error message mentions dbus-launch(1) because "X11 autolaunching",
which uses dbus-launch, is the last mechanism attempted before giving up.

Applications that benefit from a D-Bus session bus but do not strictly
require it should use a weaker dependency on the same virtual packages,
either Recommends or Suggests (I don't know which strength of dependency
is most appropriate for guake). For example, xfce4-terminal uses
Recommends for this.

The version of guake in testing/unstable already indirectly depends on
a D-Bus session bus, via GSettings, but ideally it would have this as a
direct dependency too (assuming it's still a requirement).

    smcv