go-enum-encoding

go install github.com/nikolaydubina/go-enum-encoding@latest

• 200 LOC
• simple, fast, strict
• generate encoding/decoding, tests, benchmarks

type Color struct{ c uint8 }

//go:generate go-enum-encoding -type=Color
var (
	UndefinedColor = Color{} 	// json:""
	Red            = Color{1}	// json:"red"
	Green          = Color{2}	// json:"green"
	Blue           = Color{3}	// json:"blue"
)

iota is ok too

type Size uint8

//go:generate go-enum-encoding -type=Size
const (
	UndefinedSize Size = iota // json:""
	Small                     // json:"small"
	Large                     // json:"large"
	XLarge                    // json:"xlarge"
)

generated benchmarks

$ go test -bench=. -benchmem .                  
goos: darwin
goarch: arm64
pkg: github.com/nikolaydubina/go-enum-encoding/internal/testdata
cpu: Apple M3 Max
BenchmarkColor_UnmarshalText-16         752573839                1.374 ns/op           0 B/op          0 allocs/op
BenchmarkColor_AppendText-16            450123993                2.676 ns/op           0 B/op          0 allocs/op
BenchmarkColor_MarshalText-16           80059376                13.68 ns/op            8 B/op          1 allocs/op
BenchmarkImageSize_UnmarshalText-16     751743885                1.601 ns/op           0 B/op          0 allocs/op
BenchmarkImageSize_AppendText-16        500286883                2.402 ns/op           0 B/op          0 allocs/op
BenchmarkImageSize_MarshalText-16       81467318                16.46 ns/op            8 B/op          1 allocs/op
BenchmarkImageSize_String-16            856463289                1.330 ns/op           0 B/op          0 allocs/op
PASS
ok      github.com/nikolaydubina/go-enum-encoding/internal/testdata     8.561s

References

• http://github.com/zarldev/goenums - does much more advanced struct generation, generates all enum utilities besides encoding, does not generate tests, uses similar notation to trigger go:generate but with different comment directives (non-json field tags)
• http://github.com/nikolaydubina/go-enum-example