Node / rns-mirrors / Reticulum-Go.git / files / examples / wasm / vendor / github.com / dunglas / httpsfv / decimal.go

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package httpsfv

import (

"errors"

"io"

"math"

"strconv"

"strings"

)

const maxDecDigit = 3

// ErrInvalidDecimal is returned when a decimal is invalid.

var ErrInvalidDecimal = errors.New("the integer portion is larger than 12 digits: invalid decimal")

// marshalDecimal serializes as defined in

// https://httpwg.org/specs/rfc9651.html#ser-decimal.

//

// TODO(dunglas): add support for decimal float type when one will be available

// (https://github.com/golang/go/issues/19787)

func marshalDecimal(b io.StringWriter, d float64) error {

const TH = 0.001

rounded := math.RoundToEven(d/TH) * TH

i, frac := math.Modf(rounded)

if i < -999999999999 || i > 999999999999 {

return ErrInvalidDecimal

}

if _, err := b.WriteString(strings.TrimRight(strconv.FormatFloat(rounded, 'f', 3, 64), "0")); err != nil {

return err

}

if frac == 0 {

_, err := b.WriteString("0")

return err

}

return nil

}

func parseDecimal(s *scanner, decSepOff int, str string, neg bool) (float64, error) {

if decSepOff == s.off-1 {

return 0, &UnmarshalError{s.off, ErrInvalidDecimalFormat}

}

if len(s.data[decSepOff+1:s.off]) > maxDecDigit {

return 0, &UnmarshalError{s.off, ErrNumberOutOfRange}

}

i, err := strconv.ParseFloat(str, 64)

if err != nil {

// Should never happen

return 0, &UnmarshalError{s.off, err}

}

if neg {

i = -i

}

return i, nil

}