App::Yath::Command - Base class for yath commands


This is the base class for any/all yath commands. If you wish to add a new yath command you should subclass this package.


    package App::Yath::Command::mycommand;
    use strict;
    use warnings;

    use App::Yath::Options();
    use parent 'App::Yath::Command';

    # Include existing option sets

    # Add some custom options
    option_group {prefix => 'mycommand', category => 'mycommand options'} => sub {
        option foo => (
            description => "the foo option",
            default     => 0,

    # This is used to sort/group commands in the "yath help" output
    sub group { 'thirdparty' }

    # Brief 1-line summary
    sub summary { "This is a third party command, it does stuff..." }

    # Longer description of the command (used in yath help mycommand)
    sub description {
        return <<"    EOT";
    This command does:

    # Entrypoint
    sub run {
        my $self = shift;

        my $settings = $self->settings;
        my $args     = $self->args;

        print "Hello Third Party!\n"

        # Return an exit value.
        return 0;


$string = $cmd_class->cli_help(settings => $settings, options => $options)

This method generates the command line help for any given command. In general you will NOT want to override this.

$settings should be an instance of Test2::Harness::Settings.

$options should be an instance of App::Yath::Options if provided. This method is usually capable of filling in the details when this is omitted.

$multi_line_string = $cmd_class->description()

Long-form description of the command. Used in cli_help().

@list = $cmd_class->doc_args()

A list of argument names to the command, used to generate documentation.

$string = $cmd_class->generate_pod()

This can be used to generate POD documentation from the command itself using the other fields listed in this section, as well as all applicable command lines options specified in the command.

$string = $cmd_class->group()

Used for sorting/grouping commands in the yath help output.

Existing groups:

    ' test'     # Space in front to make sure test related command float up
    'log'       # Log processing commands
    'persist'   # Commands related to the persistent runner
    'zinit'     # The init command and related command sink to the bottom.

Unless your command OBVIOUSLY and CLEARLY belongs in one of the above groups you should probably create your own. Please do not prefix it with a space to make it float, ' test' is a special case, you are not that special.

$string = $cmd_class->name()

Name of the command. By default this is the last part of the package name. You will probably never want to override this.

$short_string = $cmd_class->summary()

A short summary of what this command is.


$bool = $cmd->always_keep_dir()

By default the working directory is deleted when yath exits. Some commands such as App::Yath::Command::start need to keep the directory. Override this method to return true if your command uses the workdir and needs to keep it.

$arrayref = $cmd->args()

Get an arrayref of command line arguments AFTER options have been process/removed.

$bool = $cmd->internal_only()

Set this to true if you do not want your command to show up in the help output.

$exit_code = $cmd->run()

This is the main entrypoint for the command. You MUST override this. This method should return an exit code.

$settings = $cmd->settings()

Get the settings as populated by the command line options.

$cmd->write_settings_to($directory, $filename)

A helper method to write the settings to a specified directory and filename. File is written as JSON.

If you are subclassing another command such as App::Yath::Command::test you may want to override this to a no-op to prevent the settings file from being written, the App::Yath::Command:run command does this.


The source code repository for Test2-Harness can be found at


Chad Granum <>


Chad Granum <>


Copyright 2020 Chad Granum <>.

This program is free software; you can redistribute it and/or modify it under the same terms as Perl itself.