Question 1

How to create subcommands with spaces in Commander?

Accepted Answer

Commander supports multi-word commands directly using strings with spaces, like 'drupal module install'. Define commands with c.syntax including spaces, and it automatically handles the hierarchy without additional configuration.

Question 2

Commander vs Thor for Ruby CLI: which is better?

Accepted Answer

Commander offers more built-in features like auto-help and interactive utilities, making it ideal for rich, interactive apps. Thor is lighter and more task-focused, better for simpler scripts or Rails generators where minimalism is key.

Question 3

Can I disable the default help and version options in Commander?

Accepted Answer

While Commander provides global -h and --version flags by default, you can customize or override them using global_option methods, but completely removing them might require workarounds as they're core to the framework's design.

Question 4

How to test a CLI application built with Commander?

Accepted Answer

Test by instantiating your application class in unit tests and mocking STDIN/STDOUT, or use integration testing tools like Aruba. Since Commander runs via run!, you can isolate command logic for easier testing.

Question 5

Is Commander good for one-off Ruby scripts?

Accepted Answer

For very simple scripts, Commander might be overkill due to its setup and dependencies. Using plain OptionParser or lighter libraries is often more appropriate to avoid unnecessary complexity.

Question 6

How to add custom validation for options in Commander?

Accepted Answer

Use blocks with the option method to include validation logic, e.g., c.option '--age YEARS', Integer { |q| q.in = 0..120 } ensures values are within a range, leveraging HighLine's validation features.

Question 7

How to handle errors and exceptions in Commander commands?

Accepted Answer

Commander provides global tracing options with -t or --trace for debugging. Wrap action blocks in rescue clauses or use methods like always_trace! to control error display, but error handling largely relies on user implementation.

Commander

What is Commander?

Overview

Use Cases

Best For

Related Projects

Found a gem we're missing?

Not Ideal For

Pros & Cons

Pros

Cons

Frequently Asked Questions