use Test::More;
use vars qw($n_tests);

use_ok 'Foo::bar';
BEGIN { $n_tests++ }

my $c = 10;
for (1..$c) {
   ok Foo::new->($_);
}
# BEGIN { $n_tests += $c } # oops, wrong. my $c not visible here
BEGIN { $n_tests += 10 }

# ... and so on
# at last:

BEGIN { plan tests => $n_tests }