sub my_wrapper {
    my ($name, $xml) = @_;
    subtest 'My subtest' => sub {
         like( $xml, qr/xml version=/, "$name: XML Document");
    };
}

my $m1Xml = MyPackage::method1();
my_wrapper( 'Method 1 XML', $m1Xml);
my $m2Xml = MyPackage::method2();
my_wrapper( 'Method 2 XML', $m2Xml);