Function oracleRandomJSONValue

reference_oracle_test.go:163–231

oracleRandomJSONValue builds a random nested Go value suitable for json.Marshal. It is intentionally richer than property_test.go's generator: it emits empty containers, large integers, unicode strings, and mixed types at every depth.

(r *mathrand.Rand, depth int)

// it emits empty containers, large integers, unicode strings, and mixed
// types at every depth.
func oracleRandomJSONValue(r *mathrand.Rand, depth int) interface{} {
	if depth <= 0 {
		switch r.Intn(7) {
		case 0:
			// Large-int bias: pick from boundary table half the time,
			// random int64 the other half.
			if r.Intn(2) == 0 {
				return oracleLargeInts[r.Intn(len(oracleLargeInts))]
			}
			return r.Int63()
		case 1:
			// Random float, including subnormals and large magnitudes.
			switch r.Intn(4) {
			case 0:
				return r.Float64()
			case 1:
				return -r.Float64()
			case 2:
				return float64(r.Int63()) * 1e10
			default:
				return r.NormFloat64()
			}
		case 2:
			return r.Intn(2) == 0
		case 3:
			return nil
		case 4:
			return oracleUnicodeStrings[r.Intn(len(oracleUnicodeStrings))]
		case 5:
			// Small integer (common case).
			return r.Intn(100)
		default:
			return oracleLargeInts[r.Intn(len(oracleLargeInts))]
		}
	}
	switch r.Intn(4) {
	case 0:
		return oracleUnicodeStrings[r.Intn(len(oracleUnicodeStrings))]
	case 1:
		// Array — half the time empty.
		if r.Intn(5) == 0 {
			return []interface{}{}
		}
		n := r.Intn(5) + 1
		arr := make([]interface{}, n)
		for i := range arr {
			arr[i] = oracleRandomJSONValue(r, depth-1)
		}
		return arr
	default:
		// Object — half the time empty.
		if r.Intn(5) == 0 {
			return map[string]interface{}{}
		}
		n := r.Intn(5) + 1
		obj := make(map[string]interface{}, n)
		used := map[string]bool{}
		for i := 0; i < n; i++ {