Bug#456629: lintian: detect missing version mangling in debian/watch for dfsg-ed packages

[Patrick Schoenfeld <schoenfeld@in-medias-res.com>]

Hi,

> In case of packages that have been modified to comply with DFSG, it is
> necessary that either opts=uversionmangle or opts=dversionmangle is used
> in the debian/watch file if the file exists.  Failing which, uscan
> reports that the current version itself is not available on the site.

Yep, that is true. As my AM asked me to write a check for such things
I'll look into this the next days.

> It would be useful to have a check that warns about this (it could even
> be an error because the watch file is useless without the version
> mangling option).

I'm not sure if a warning is appropriate as it is not a must to have
functional watch file, according to policy. According to policy it is
fully optional and therefore should be encouraged but not forced. So I
think that an informative message is more appropriate.

Best Regards,
Patrick