No, see, I want to establish a set_up/tear_down that are exectuted not once for each test, but a set_up that is run once before the first test is run, and a teat_down that is run once after the last test is run.

Test::Unit::Setup is a decorator for suites, not test cases, so you'll need to do something like this:

package My::TestCase;
use base qw(Test::Unit::TestCase);
use Test::Unit::TestSuite;

sub test_the_first {
    my $self = shift;
    $self->assert( 1, 'first' );
}   

sub test_the_second {
    my $self = shift;
    $self->assert( 1, 'second' );
}   

sub suite {
    return MySuiteSetup->new(
        Test::Unit::TestSuite->new( __PACKAGE__ )
    );
}

package MySuiteSetup;
use base qw( Test::Unit::Setup );

sub set_up {
    warn "before all tests\n";
}

sub tear_down {
    warn "after all tests\n";
}
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Our group is already pretty heavily invested in Test::Unit, but I can ask the other guys what they think of Test::Class

Just as a point of comparison, this would be how you would do it in Test::Class.

package My::Test;
use base qw( Test::Class );
use Test::More;

sub before :Test( startup ) {
    warn "before all tests\n";
};

sub first :Test { pass };

sub second :Test { pass };

sub after :Test( shutdown ) {
    warn "after all tests\n";
};
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You might also be interested in PerlUnit@yahoogroups.com, a mailing list dedicated to Test::Unit. Traffic has been sparse though...