[...] # Init tests, prepare everything, etc.
require 'error.inc'; # Here are the regular handling functions defined, Log_Error is one of them

our $ErrorText;
our $ErrorLevel;

eval {
 sub Log_Error {
  ($ErrorText,$ErrorLevel) = @_;
  return 1;
 }
};

##</code><code>##

# for expected errors:
ok($ErrorText eq 'foo','Error-checking');
ok($ErrorLevel eq 'mail','Error-level-checking');
# for tests which shouldn't trigger one:
ok($ErrorText eq '','Check for errors');