anchor.diff:        description = "Perl Interface to the Domain Name System";
         license = stdenv.lib.licenses.mit;
       };
  +  };
  +
  +  NetDNSResolverMock = buildPerlPackage rec {
  +     name = "Net-DNS-Resolver-Mock-1.20171219";
  +     src = fetchurl {
  +       url = mirror://cpan/authors/id/M/MB/MBRADSHAW/Net-DNS-Resolver-Mock-1.20171219.tar.gz;
  +       sha256 = "0m3rxpkv1b9121srvbqkrgzg4m8mnydiydqv34in1i1ixwrl6jn9";
  +     };
  +     propagatedBuildInputs = [ NetDNS ];
  +     meta = {
  +       description = "Mock a DNS Resolver object for testing";
  +       license = with stdenv.lib.licenses; [ artistic1 gpl1Plus ];
  +     };
     };
   
     NetDomainTLD = buildPerlPackage rec {
  
positive.code:     };
    };
  
    TestRoo = buildPerlPackage rec {
      name = "Test-Roo-1.004";
      src = fetchurl {
  
negative.code:   };
  
    MailDKIM = buildPerlPackage rec {
      name = "Mail-DKIM-0.52";
      src = fetchurl {
        url = mirror://cpan/authors/id/M/MB/MBRADSHAW/Mail-DKIM-0.52.tar.gz;
        sha256 = "1dbczg7vyvvm12d9gbiqd9a24qg4254cz7bh7yf3p27i58hhpbwy";
      };
      propagatedBuildInputs = [ CryptOpenSSLRSA MailTools NetDNSResolverMock YAMLLibYAML ];
      doCheck = false; # tries to access the domain name system
      buildInputs = [ TestRequiresInternet ];
    };
  
    MailIMAPClient = buildPerlPackage {
  