golang-testing

Table-driven tests in Go use a slice of test cases with inputs and expected outputs, iterating through each case in a single test function. This pattern reduces code duplication and makes it easy to add new test scenarios without writing separate test functions.

Interface-based mocking is the standard Go approach: define interfaces for dependencies, create test doubles implementing those interfaces, and inject them during testing. This avoids external coupling and enables comprehensive unit testing without external services.

Yes, testcontainers enable integration testing by spinning up containerized versions of databases, message queues, and APIs. Your tests interact with real service instances in isolated containers, then tear them down automatically after tests complete.

Go's built-in benchmarking uses functions named BenchmarkX in test files and runs with `go test -bench`. Benchmarks measure execution time and memory allocation, helping identify performance bottlenecks and track optimization progress across releases.

Testify provides assertions and mocking helpers that simplify test code. Testcontainers handles integration test infrastructure. The standard library's testing package covers unit tests and benchmarks. Together they cover unit, integration, and performance testing needs.

Place test files alongside source code with a `_test.go` suffix in the same package. Group related tests logically, use table-driven patterns for similar cases, and keep test setup in helper functions. This structure keeps tests maintainable and discoverable with `go test`.