Test::Output is interesting, but I had to make a few adjustments to get it to work. I took Grandfather's script, added a test from Test::Output. 
package Test_Package;

use strict;

sub testing {
   print "okay";
};

1;

use strict;
use Test::Output;
use Test::More tests => 4;

my $log;
open my $logFile, '>', \$log;
my $oldStdOut = select $logFile;

Test_Package->testing(\$log);
select $oldStdOut;
close $logFile;

stdout_is {print "okay"} "okay", "STDOUT okay";
is('okay', 'okay');
is($log, 'okay');
is($log, 'okay', 'testing okay');

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In reply to Re^2: How to Test Output from the Standard Output by Khen1950fx
in thread How to Test Output from the Standard Output by Anonymous Monk

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