Hello Monks I have several perl scripts that I was told to write test suites for. The scripts look like this: 
#!/usr/bin/perl -w
# file somescript.pl

use strict;
use warnings;

sub SubThatNeedsToBeTested {
    # do some stuff
    if ($error ) {
      print "error occurred\n";
      exit 2;
    }
    if ($othererror) {
     print "another error occurred\n";
     exit 3;
    }
}

sub NoNeedToTestThis {
   # ...
}

## main program
&SubThatNeedsToBeTested ();
&NoNeedToTestThis ();
exit 0;

[download]

I would like to write tests only for some functions, for example for SubThatNeedsToBeTested but not for NoNeedToTestThis.

Could this be achieved without restructuring the scripts ie moving functions like SubThatNeedsToBeTested to a separate module? Can I somehow load subs into my test script namespace without executing the main program part?

Some methods call exit $errorcode. Is there a way to trap this? I was thinking about eval, but it only traps die.

How would you test this without restructuring the scripts too much?

Thank you for your answers

In reply to Testing parts of perl scripts by koo

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