Bug#698723: lintian: Error on different trigger directives for the same trigger-name

[Guillem Jover <guillem@debian.org>]

Package: lintian
Version: 2.5.12
Severity: wishlist

Hi!

Due to 537051 we noticed that the documentation for the triggers
control file directives is not really clear. Using the two different
directives for the same trigger names is pretty confusing as only the
last one will be honoured. Things like this in the .deb triggers
control file:

,--- DEBIAN/triggers
| interest-noawait foo
| interest foo
`---

would only add a non-awaiting trigger to the dpkg database. The same
goes for activate-noawait/activate. Ideally dpkg would contain better
documentation explaining this, and the code would make sure this never
happens at build time, and warn at unpack time, etc. For further
details of the situation that brought up this, read starting at:

  <http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=537051#90>

So it would be nice if lintian could emit an error tag for those
conditions. I've added to my TODO to improve this for dpkg 1.17.x,
but even then the lintian check would still be useful as there might
be packages in the wild with stuff like the above.

Thanks,
Guillem