use XML::Twig;

my %hash;

my $twig = XML::Twig->new(
   twig_handlers => {
       testcase => sub { # this gets called per each testcase in XML
           my ($t,$e) = @_;
           my $testcase = $e->att("name");
           my $error = $e->field("error") || $e->field("failure");
           my $ok = defined $error ? "not ok" : "ok";
           # you may want to collect
           #   testcase name,result,error message,etc into hash
           $hash{$testcase}{result} = $ok;
           $hash{$testcase}{error}  = $error;
           # ...
       }
   }
);
$twig->parsefile("test.xml");
$twig->purge();

# Now XML processing is done,print hash out in TAP format:
print "1..",scalar(keys(%hash)),"\n";
foreach my $testcase (keys %hash) {
     # print out testcase result using info from hash
     # don't forget to add leading space for errors
     # ...
}

这应该比较容易抛光成工作状态