arc

Arc is a command line tool and a part of the Arcanist software suite developed by Facebook. It is primarily used for interacting with the code review system called Differential.

Arc provides a set of commands that help developers perform various tasks related to code reviews and version control. Some of the key features of Arc include:

1. Differential Integration: Arc allows users to create and update code differentials in the Differential code review system. It provides commands for creating new code reviews, updating existing ones, and applying changesets to a differential.

2. Version Control Integration: Arc supports integration with popular version control systems like Git and Mercurial. It provides commands for committing changes, creating and switching branches, and pushing changes to remote repositories.

3. Unit Testing: Arc includes commands to run unit tests on code changes locally before pushing them for review. This helps developers ensure the quality of code and catch any issues before sending them for review.

4. Phabricator Integration: Arc is tightly integrated with Phabricator, an open-source collaboration platform developed by Facebook. It enables seamless interaction between Arc and Phabricator, allowing users to perform tasks like creating tasks, updating task statuses, and querying task information.

5. Customizable Configuration: Arc provides a customizable configuration file that allows users to specify project-specific settings and behaviors. This includes defining code review policies, configuring linters, and setting up project-specific hooks.

Arc is widely used within Facebook and many other companies that utilize Phabricator as their code review platform. It simplifies the process of submitting and reviewing code, enabling efficient collaboration between developers.