Bug#848337: dh-make-perl: Require user intervention to resolve version ambiguity

[Christopher Hoskin]

Package: dh-make-perl
Version: 0.92
Severity: normal
Tags: patch

Dear Maintainer,

Upstream developers sometimes upload Perl modules to CPAN, forgetting to update
the version in the META, Build or Makefile. In these situations, dh-make-perl 
ignores the CPAN version and trusts the META.yml version, without making the 
packager aware of the discrepancy. Examples of upstream modules where this has
happened are Cache::Memcached::libmemcached and Catalyst::View::CSV.

The attached patch causes dh-make-perl to quit if the module version does not
match the CPAN version, and requires the user to explicity specify the version
with --version.

This reduces the likelihood of the packager uploading a package with a version
number which does not correspond to the actual upstream version.

Thanks.

Christopher Hoskin

>From 71938776dbb0b3ab7d6f35c009ee675655449639 Mon Sep 17 00:00:00 2001
From: Christopher Hoskin <christopher.hos...@gmail.com>
Date: Fri, 16 Dec 2016 11:12:47 +0000
Subject: [PATCH] Require user intervention to resolve version ambiguity

---
 lib/DhMakePerl/Command/Packaging.pm | 10 ++++++++--
 1 file changed, 8 insertions(+), 2 deletions(-)

diff --git a/lib/DhMakePerl/Command/Packaging.pm b/lib/DhMakePerl/Command/Packaging.pm
index 2b07ac4..d759b66 100644
--- a/lib/DhMakePerl/Command/Packaging.pm
+++ b/lib/DhMakePerl/Command/Packaging.pm
@@ -356,8 +356,14 @@ sub extract_name_ver {
         $ver  = $self->version;
     }
 
-    $ver = $self->cfg->version
-        if $self->cfg->version;
+    if ($self->cfg->version) {
+        #Version specified on command line trumps other versions
+        $ver = $self->cfg->version
+    } elsif ( $self->mod_cpan_version ) {
+        if ($self->mod_cpan_version != $ver) {
+            die "Version ambiguity, cpan has ".$self->mod_cpan_version.", module has ".$ver.". Please specify version with --version.\n";
+        }
+    }
 
     # final sanitazing of name and version
     $name =~ s/::/-/g if defined $name;
-- 
2.10.2