Bug#867104: wanna-build issue with src:perl versioned Provides

[Niko Tyni <ntyni@debian.org>]

Package: buildd.debian.org
X-Debbugs-Cc: debian-perl@lists.debian.org
User: debian-perl@lists.debian.org
Usertags: versioned-provides

As discussed in the thread at

 https://lists.debian.org/debian-devel/2017/06/msg00236.html
 https://lists.debian.org/debian-devel/2017/07/msg00026.html

src:perl recently started to use versioned Provides.
This seems to have broken wanna-build, despite #786671 being
fixed during the stretch cycle. See for instance

 https://buildd.debian.org/status/package.php?p=libpgobject-type-datetime-perl
 https://buildd.debian.org/status/package.php?p=libtime-moment-perl

where the 'dependency installibility problems' look incorrect to me
and the build dependencies can be downloaded fine with 'apt build-dep'
and the like.

Do you think this is fixable? Should I be looking at reverting
the versioned Provides change for now? Maybe it's "just" the
wanna-build host still running jessie and not stretch?

Copying the debian-perl list as multiple perl packages are affected.

Example copy-paste below. The perl-base/5.24.1-5 package currently

 Breaks:   libscalar-list-utils-perl (<< 1:1.42.02)
 Replaces: libscalar-list-utils-perl (<< 1:1.42.02)
 Provides: libscalar-list-utils-perl  (= 1:1.42.02)

and the change that triggered this was moving from traditional
unversioned Provides.

  Dependency installability problem for libtime-moment-perl on arm64:
  
  libtime-moment-perl build-depends on:
  - libdatetime-perl:arm64
  libdatetime-perl depends on:
  - libdatetime-locale-perl:arm64 (>= 1:1.06)
  libdatetime-locale-perl depends on:
  - libscalar-list-utils-perl:arm64 (>= 1:1.45) | libscalar-list-utils-perl:arm64 (>= 1:1.45) | perl:arm64 (>= 5.25)
  libtime-moment-perl build-depends on:
  - libdatetime-perl:arm64
  libdatetime-perl depends on:
  - libdatetime-locale-perl:arm64 (>= 1:1.06)
  libdatetime-locale-perl depends on:
  - libscalar-list-utils-perl:arm64 (>= 1:1.45) | libscalar-list-utils-perl:arm64 (>= 1:1.45) | perl:arm64 (>= 5.25)
  libscalar-list-utils-perl depends on:
  - 
  libscalar-list-utils-perl conflicts with:
  - libscalar-list-utils-perl:arm64
  
-- 
Niko Tyni   ntyni@debian.org