Catch2 is a comprehensive framework for C++ software validation, providing an environment for unit testing, integration verification, and performance analysis. It enables developers to define and execute automated test suites and micro-benchmarks directly within their applications.
The framework is distinguished by its header-only distribution, which allows for integration into existing build systems without requiring complex external dependencies. It utilizes a hierarchical section-based execution model that supports behavior-driven testing, allowing for shared setup and teardown logic across nested test scenarios. Additionally, the library employs an expression-decomposition assertion system that breaks down complex boolean expressions to report specific sub-expression values upon failure.
The project covers a broad range of validation capabilities, including automated regression testing and granular unit testing of individual functions. It also provides tools for measuring execution duration across varying hardware and compiler configurations to identify performance bottlenecks. The library is designed for simple inclusion, with test registration handled through static macros that collect function pointers at compile time.