my $LOG_ERROR;                                                                                         
my $_log_error_sub_cache;
sub setup
{
    my $class = shift;
    $class->SUPER::setup_test;
    $_log_error_sub_cache = *RTK::Digitrak::LogRun::_log_error{CODE};
    no warnings 'redefine';
    *Foo::Bar_log_error = sub($) { $LOG_ERROR = shift };
}                                                                                                 

sub teardown
{
    my $class = shift;
    $class->SUPER::teardown_test;
    no warnings 'redefine';
    *Foo::Bar:_log_error = $_log_error_sub_cache;
}

##</code><code>##

use Foo::Test::LogMessages;
my $log = Foo::Test::LogMessages->new;

sub TEST_WHICH_HAS_LOG_OUTPUT
{
  # do something
  $log->capture_log_only_for_this_scope;
  is($log->message, qw/some message/, '... and we should have an error');
}

sub TEST_WHICH_DOES_NOT_HAVE_LOG_OUTPUT
{
  # do something
}