Fuzz Testing
Go 1.18 shipped something remarkable: built-in fuzz testing integrated directly into go test. No external tools, no compilation flags, no special setup — just write a FuzzXxx function and run go test -fuzz. This guide covers native Go fuzzing, the older dvyukov/go-fuzz library, and how to write fuzz targets
Go
Table-driven tests are Go's idiomatic approach to testing multiple input/output combinations. Instead of writing one test function per case, you define all cases as a slice of structs and loop through them. The Go standard library itself uses this pattern extensively. The Basic Pattern func TestAdd(t
Go
testify is the most popular Go testing library. It provides three main packages: assert for fluent assertions, require for fail-fast assertions, mock for interface mocking, and suite for test organization. While the standard testing package is sufficient for simple cases, testify makes complex test suites significantly more readable. Installation go
Go
Go ships with a built-in testing package that requires no third-party dependencies. The go test command finds and runs tests automatically. You don't need to configure a test runner, register test files, or install plugins. This built-in simplicity is one of Go's strongest features for developer
Go
Unit tests verify logic in isolation. Integration tests verify that components work together: your code + database, your service + external API, your handler + middleware stack. Go's testing package supports both, and the patterns for integration testing are as idiomatic as those for unit testing. Separating Integration Tests Mark slow
Go
Go's testing package includes a built-in benchmark system. Benchmarks measure how long code takes to run and how much memory it allocates. They're the right tool for validating optimization work and catching performance regressions. Writing Benchmarks Benchmark functions start with Bench and take *testing.B: func
Go
Mocking in Go is interface-based. You define an interface, generate a mock implementation, and use it in tests to control behavior and verify interactions. The two main tools are gomock (from the Google team) and mockery (a third-party code generator). This tutorial covers both. Why Mock? Pure unit tests isolate