Agent Skills: Go Testing & Quality

Go Testing & Quality

Idiomatic, 2026-current testing and quality practices for Go, built on the standard testing package with testify where it adds clarity.

Use when:

• Writing unit tests for Go code (table-driven, subtests)
• Adding assertions or mocks with testify (assert / require / mock)
• Writing fuzz tests, benchmarks, or example tests
• Measuring coverage (go test -cover) or chasing race conditions (-race)
• Profiling / optimizing with pprof or setting up PGO
• Reviewing an existing Go test suite for quality gaps

Do NOT use for:

• Project layout, routing, DB wiring, DI — use go-architecture
• SOLID line-limit / interface enforcement — use fuse-solid:solid-go
• Non-Go test suites (Pest, Vitest, Jest, cargo test) — use the matching expert
• Security scanning / CVE audit — use fuse-security

Decision Map

| Goal | Load | |------|------| | Write the standard Go test (table-driven + subtests) | table-driven.md | | Assertions and mocks with testify | testify-mocks.md | | Fuzzing, benchmarks, example tests | fuzzing-benchmarks.md | | Coverage, race detector, pprof, PGO | coverage-profiling.md | | A complete, runnable test file to copy | templates/table-test.md |

Core Practices (2026)

1. Table-driven tests are the idiom. Define a slice of cases, loop, and run each as a subtest with t.Run(tc.name, …) for isolation and readable output.
2. testify is the de-facto assertion/mock standard. assert for soft checks, require to abort on failure, mock for hand-written mocks, suite for setup/teardown groups. It is maintained at v1 (no breaking v2). Source: https://pkg.go.dev/github.com/stretchr/testify
3. Fuzzing is native since Go 1.18 (func FuzzXxx(f *testing.F)), and finds edge cases table tests miss.
4. Always run -race in CI. The race detector catches data races that are otherwise nondeterministic and unreproducible.
5. Measure before optimizing. Benchmarks (go test -bench) + pprof profiles guide real changes; PGO feeds a production profile back into the compiler.

Workflow

1. Explore the code under test and existing test conventions first.
2. Write table-driven tests as the default shape (table-driven.md).
3. Add testify assertions/mocks where they improve readability, not reflexively.
4. Run go test ./... -race -cover and inspect gaps.
5. Fuzz / benchmark hotspots and parsers (fuzzing-benchmarks.md).
6. Profile only after a benchmark proves a hotspot (coverage-profiling.md).
7. Validate with sniper after changes.

Boundaries

Overlaps with github.com/samber/cc-skills-golang (community Go skills) — this skill owns testing and quality tooling; architecture/structure lives in go-architecture. Cross-referenced for boundaries only, not copied.