SimpleCov is a code coverage analysis tool for Ruby 1.9. It uses 1.9’s built-in Coverage library to gather code coverage data, but makes processing it’s results much easier by providing a clean API to filter, group, merge, format and display those results, thus giving you a complete code coverage suite with just a couple lines of code.

Christoph Olszowka

SimpleCov builds on the ideas presented in Aaron Patterson's recent, and awesome, Writing a Code Coverage Tool with Ruby 1.9 blog post. The result is a powerful yet straightforward code coverage tool that puts out some well formatted stats.