Codecov’s Components feature provides a powerful tool to isolate and categorize coverage data from your project, using filters that can be defined in your codecov.yml. You can use components you specify to create custom statuses and get coverage information from parts of your code that are not easily broken up into different uploads or span multiple flag groups.
Unlike Flags, Components do not have to be supplied at upload time. Instead, they are fully defined in the codecov.yml file, making it easy to manage and update your Components without ever having to change the way you run tests in your CI. When Codecov processes coverage reports that you upload, it looks for the files that you have grouped together as Components and aggregates their coverage together. This aggregated coverage can then be used in status checks and the Codecov PR comment, with support in the Codecov UI coming soon.
