rust-testing

Rust testing organizes unit tests within the src directory alongside source modules, and integration tests in a dedicated top-level tests directory. This separation validates module-level logic independently from external API contracts.

Property-based testing in Rust validates code correctness by automatically generating varied inputs to verify universal invariants. Using proptest, developers define logical properties rather than fixed examples, exposing hidden edge cases across the generated test cases.

Mocking in Rust using mockall generates mock implementations of traits to isolate components during test execution. Developers apply mockall to define expected method calls and return values, verifying interactions without relying on external dependencies or real side effects.

cargo-nextest works with existing Rust test suites by acting as a faster, more reliable test runner for standard cargo tests. It integrates seamlessly into development and CI workflows to execute unit, integration, and property-based tests with improved parallelism and reporting.

Benchmarking Rust code performance is best handled using criterion, which integrates into the Rust testing workflow to measure execution speed and detect regressions. Criterion provides statistical analysis and detailed reporting to validate performance across development iterations.

Running Rust benchmarks and unit tests in the same CI workflow is fully supported by combining criterion for performance measurement and cargo-nextest for test execution. This setup validates both functional correctness and execution speed across continuous integration pipelines.