Conference in the Cloud (A Perl and Raku Conference)

The "modulino" format allows a command line script to behave like a module that can be tested with familiar test harness tools (i.e. Test::More and Test::MockModule) without executing it, often achieving very high coverage numbers. It is only natural to bring Moo to the game.

The basic idea of a “modulino” is to take advantage of the caller() function to determine if a script is being run from the command line or being included by a require statement. This allows the code to behave as either a normal script or as a module. It is the latter behavior that enables a modulino to be fully testable without having to execute it and capture the output somehow. It allows full unit testing with tools such as Test::More and Test::MockModule.

Moo brings a well-known OO framework to the party to help organize the script more like a module and provide command line parameters as object attributes.

This talk will demonstrate with simple scripts how Moo and Getopt::Long can play nice with each other and how the modulino structure benefits testing. A Role will be introduced, MooX::Role::CliOptions, to show how coding standards can be established for standard command line options.