G'day space_monk,

I tried a few tests with callback formats I'd come across elsewhere (e.g. [\&function, @args] from Perl/Tk) but subtest emits a warning that the 2nd argument must be a coderef. Given this, your best bet might be something like:

subtest 'test name' => sub { my_subtest($xml, @other_args) };
[download]

I played around with this for a bit and it seems to work well. I was able to conditionally run subtest tests based on the arguments passed in: I don't know if that's exactly what you want to do with it but it certainly "can be called a number of times with different parameters".

#!/usr/bin/env perl

use strict;
use warnings;

use Test::More tests => 9;

my $xml = '<tag>content</tag>';

pass('PRE subtest');

subtest 'xml_subtest(undef)'
    => sub { xml_subtest(undef) };
subtest 'xml_subtest("blah")' 
    => sub { xml_subtest("blah") };
subtest 'xml_subtest("blah", undef)' 
    => sub { xml_subtest("blah", undef) };
subtest 'xml_subtest("blah", {})' 
    => sub { xml_subtest("blah", {}) };
subtest 'xml_subtest($xml, {test_format => 1})'
    => sub { xml_subtest($xml, {test_format => 1}) };
subtest 'xml_subtest($xml, {test_tag => 1})' 
    => sub { xml_subtest($xml, {test_tag => 1}) };
subtest 'xml_subtest($xml, {test_content => 1})' 
    => sub { xml_subtest($xml, {test_content => 1}) };

pass('POST subtest');

sub xml_subtest {
    my ($sub_xml, $args) = @_;

    plan tests => 5;

    ok(defined $sub_xml,    '$sub_xml defined');
    ok(length $sub_xml,     '$sub_xml populated');
    ok(defined $args,       '$args defined');
    ok(ref $args eq 'HASH', '$args is hashref');

    if ($args->{test_format}) {
        like($sub_xml, qr{^<([a-z]+)>[^<]+</\1>$},
            '$sub_xml well-formed');
    }
    elsif ($args->{test_tag}) {
        is(($sub_xml =~ m{^<([a-z]+)>})[0], 'tag',
            '$sub_xml tag element');
    }
    elsif ($args->{test_content}) {
        cmp_ok(($sub_xml =~ m{>([^<]+)<})[0], 'eq', 'content',
            '$sub_xml tag content');
    }
    else {
        fail('No tests indicated');
    }
}
[download]

Test results: