Assert distribution support

This takes the approach that if a distribution is supported, it should
support certain versions that Foreman supports.

spec/puppet_version_spec.rb

@@ -3,6 +3,12 @@
 
 describe 'Puppet module' do
   VERSIONS = ['5.5.10', '6.0.0'].map { |v| SemanticPuppet::Version.parse(v) }
+  DISTROS = {
+    'CentOS' => ['7'],
+    'Debian' => ['10'],
+    'RedHat' => ['7'],
+    'Ubuntu' => ['18.04'],
+  }
 
   Dir.glob(File.join(__dir__, '../_build/modules/*/metadata.json')).each do |filename|
     context File.basename(File.dirname(filename)) do
@@ -14,12 +20,32 @@
         version_requirement ||= '>= 0'
         SemanticPuppet::VersionRange.parse(version_requirement)
       end
+      let(:operatingsystem_support) { metadata['operatingsystem_support'] }
 
       VERSIONS.each do |puppet_version|
         it "should support Puppet #{puppet_version}" do
           expect(puppet_requirement).to include(puppet_version)
         end
       end
+
+      DISTROS.each do |distro, versions|
+        versions.each do |version|
+          it "should support #{distro} #{version}" do
+            if operatingsystem_support.nil?
+              skip "No OS support listed"
+            end
+
+            distro_versions = operatingsystem_support.find { |os| os['operatingsystem'] == distro }
+
+            if distro_versions.nil?
+              skip "Distribution #{distro} is not supported"
+            end
+
+            expect(distro_versions).to have_key('operatingsystemrelease')
+            expect(distro_versions['operatingsystemrelease']).to include(version)
+          end
+        end
+      end
     end
   end
 end