Aruba is a Ruby gem designed for testing command-line applications. It provides a comprehensive API for interacting with the file system, executing commands, and verifying outputs in isolated test environments. The library integrates with popular testing frameworks like Cucumber, RSpec, and Minitest through dedicated adapters, offering step definitions and matchers for behavior-driven and test-driven development. Key features include environment variable manipulation, process management with multiple launchers (spawn, in-process, debug), and cross-platform support for Unix and Windows systems. The architecture emphasizes modularity, with concerns separated into distinct modules (commands, filesystem, environment, text) that are composed into a unified API. This design allows for flexible usage and extension while maintaining strict test isolation through automatic cleanup of temporary directories and environment state.

Starter template for Cucumber-JVM with Java and Maven. It is not a production application: the only production source file is an empty Belly class, while all meaningful code lives in the test tree. RunCucumberTest is a JUnit Platform Suite that boots the Cucumber engine, cucumber.properties supplies glue and plugin configuration, and belly.feature defines one scenario whose step definitions are bound via annotations. Running `./mvnw test` executes the suite and prints pretty output; one step passes, one is intentionally aborted with a TODO, and one is undefined. The repository's actual purpose is to demonstrate a minimal Cucumber setup and serve as a starting point for BDD projects. Architecturally this is a Maven build with test-scoped dependencies only: cucumber-java, cucumber-junit-platform-engine, junit-platform-suite, and assertj-core. Dependencies are imported through BOMs, Java 17 is configured as the release target, and the Maven wrapper pins Maven 3.10.0. The primary data flow is Gherkin -> Cucumber engine -> annotated JUnit step methods -> AssertJ assertions. There is no web server, API, or business logic. The repository includes CI that runs the tests on Ubuntu and Windows across Java 17 and 21, Renovate for dependency updates, and a Zizmor workflow for GitHub Actions security analysis, indicating active project maintenance.