go-code-review

Go Language Review

This skill provides Go-specific guidance for code quality reviews. It is loaded automatically by the pre-commit-review command when --language go is specified or when .go files are detected among the changed files.

When to Use This Skill

Use this skill when reviewing Go source code. Its sections are referenced during the unit test coverage, idiomatic code, and build verification review steps.

Test Conventions

• Table-driven tests: Prefer table-driven tests for functions with multiple input/output combinations
• Subtests: Use t.Run() for subtests to provide clear test case identification
• Parallel tests: Use t.Parallel() at the top of test functions and subtests where tests are independent
• Race detection: Tests must be compatible with the -race flag — avoid shared mutable state between parallel tests
• File co-location: Test files must be co-located with source files using the _test.go suffix
• Test helpers: Use t.Helper() in test helper functions so failure messages report the caller's line number
• Behavior-focused: Test names should describe behavior, not implementation. Test both success and error paths

Idiomatic Go

Follow the conventions in Effective Go and the Go Code Review Comments wiki. Key reminders:

• Formatting: All code must be formatted with gofmt. Unformatted code is a blocking issue
• Naming: Use MixedCaps / mixedCaps. Avoid stuttering (http.Server not http.HTTPServer). Acronyms are all caps (URL, HTTP, ID)
• Error handling: Check every error. Wrap with fmt.Errorf("context: %w", err) to preserve the chain for errors.Is() / errors.As()
• Interfaces: Keep interfaces small. Accept interfaces, return concrete types
• Early returns: Handle error cases first; keep the happy path at the lowest indentation level
• Context: Pass context.Context as the first parameter to functions that perform I/O or may be long-running

Build Commands

Use the following commands in priority order during build verification:

1. Tests: make test if a Makefile with a test target exists; otherwise go test -race ./...
2. Verification: make verify if available; otherwise go vet ./...
3. Build: make build if available; otherwise go build ./...