=head2 did_succeed
Return:
* true if the task ran and finished successfully,
* false if the task did not run successfully but is completed
* undef if the task has not yet run
=cut
sub did_succeed {
    my ($self) = @_;

    if (!defined($self->end_time)) {
      return undef;
    }

    if (!defined($self->exit_code)) {
      return 0;
    }
    return $self->exit_code == 0;
}

    is($runlog->did_succeed(), undef, "The process has not yet succeeded.");

    ok($runlog->did_succeed(), "The process did succeed.");

    ok(!$runlog->did_succeed(), "The process did not succeed.");

    ok(!$runlog->did_succeed(), "The process did not succeed.");

    ok(!$runlog->did_succeed(), "The process did not succeed.");

    ok($runlog->did_succeed(), "The process did succeed.");

    ok(!$runlog->did_succeed(), "The process did not succeed.");