go-patterns

name	go-patterns
description	This skill should be used for Go idioms, error handling, goroutines, interfaces, and testing, golang, Go language, Go modules, Go concurrency
whenToUse	Go code, Go patterns, goroutines, Go testing, golang, .go files, Go modules, Go error handling, Go interfaces, Go concurrency
whenNotToUse	Non-Go code, CGo interop, Rust, other systems languages
seeAlso	[{"skill":"testing-strategies","when":"Go test architecture"},{"skill":"api-design","when":"Go HTTP services"}]

Go Patterns

Idiomatic Go patterns for Go 1.21+.

Error Handling

if err != nil {
    return fmt.Errorf("failed to process %s: %w", id, err)
}

Interfaces

Small interfaces (1-3 methods). Accept interfaces, return structs.

type Reader interface {
    Read(p []byte) (n int, err error)
}

Table-Driven Tests

tests := []struct{
    name string
    input, want int
}{
    {"positive", 2, 3},
}
for _, tt := range tests {
    t.Run(tt.name, func(t *testing.T) {
        if got := Fn(tt.input); got != tt.want {
            t.Errorf("got %d, want %d", got, tt.want)
        }
    })
}

Concurrency

Always propagate context for cancellation:

func work(ctx context.Context) error {
    select {
    case <-ctx.Done():
        return ctx.Err()
    default:
        // do work
    }
}

Defer for Cleanup

f, err := os.Open(path)
if err != nil { return err }
defer f.Close()