Bug#1014885: lintian wrongly complains about XS-Go-Import-Path

[Axel Beckert <abe@debian.org>]

Control: clone -1 2
Control: retitle -2 lintian: Needs to distinguish between valid field names for .dsc files and for debian/control files (with vs without "XS-" prefix)
Control: tag -1 + pending
Control: tag -2 + help

Hi,

Holger Levsen wrote:
> I can confirm this issue for lintian 2.116.0 against src:piuparts
> as it is in git or unstable.

I can confirm as well. Unfortunately this is not as trivial to fix
properly as it seems:

A) Lintian currently doesn't seem to make a difference between the
   fields in the .dsc file and those in the debian/control file. But
   especially these XS-* fields exactly need that differentiation.

B) If I add Autobuild, Go-Import-Path, and Ruby-Versions to
   data/common/source-fields, the test suite shows that then these
   lintian tags would fire although they shouldn't (according to the
   test suite):

   adopted-extended-field (in section for source) XS-Go-Import-Path
   adopted-extended-field (in section for source) XS-Autobuild

So for now I have no idea except for hardcoding these three inside the
source function in lib/Lintian/Check/Fields/Unknown.pm. But this feels
wrong.

This though might lead to false negatives if someone uses e.g.
Go-Import-Path without the "XS-" prefix in debian/control.

What would be worse: The current false positives or the potential
false negatives?

I assume that any potential false negative on these
three fields will cause package breakage at build time (wrong Ruby
versions, some Go stuff not working, non-free packages not
autobuilding, etc.), so that we can cope with them.

Cloning this bug report to document that we need a rewrite of
Lintian::Check::Fields::Unknown and module dependencies to distinguish
between .dsc fields and debian/control fields with a common subset.
And maybe with the one set being calculated from the other set by
stripping the XS- prefix.

		Regards, Axel
-- 
 ,''`.  |  Axel Beckert <abe@debian.org>, https://people.debian.org/~abe/
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