lbry.go/extras/null/uint8.go

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package null
import (
"bytes"
"database/sql/driver"
"encoding/json"
"fmt"
"math"
"strconv"
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"gopkg.in/nullbio/null.v6/convert"
)
// Uint8 is an nullable uint8.
type Uint8 struct {
Uint8 uint8
Valid bool
}
// NewUint8 creates a new Uint8
func NewUint8(i uint8, valid bool) Uint8 {
return Uint8{
Uint8: i,
Valid: valid,
}
}
// Uint8From creates a new Uint8 that will always be valid.
func Uint8From(i uint8) Uint8 {
return NewUint8(i, true)
}
// Uint8FromPtr creates a new Uint8 that be null if i is nil.
func Uint8FromPtr(i *uint8) Uint8 {
if i == nil {
return NewUint8(0, false)
}
return NewUint8(*i, true)
}
// UnmarshalJSON implements json.Unmarshaler.
func (u *Uint8) UnmarshalJSON(data []byte) error {
if bytes.Equal(data, NullBytes) {
u.Valid = false
u.Uint8 = 0
return nil
}
var x uint64
if err := json.Unmarshal(data, &x); err != nil {
return err
}
if x > math.MaxUint8 {
return fmt.Errorf("json: %d overflows max uint8 value", x)
}
u.Uint8 = uint8(x)
u.Valid = true
return nil
}
// UnmarshalText implements encoding.TextUnmarshaler.
func (u *Uint8) UnmarshalText(text []byte) error {
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if text == nil || len(text) == 0 {
u.Valid = false
return nil
}
var err error
res, err := strconv.ParseUint(string(text), 10, 8)
u.Valid = err == nil
if u.Valid {
u.Uint8 = uint8(res)
}
return err
}
// MarshalJSON implements json.Marshaler.
func (u Uint8) MarshalJSON() ([]byte, error) {
if !u.Valid {
return NullBytes, nil
}
return []byte(strconv.FormatUint(uint64(u.Uint8), 10)), nil
}
// MarshalText implements encoding.TextMarshaler.
func (u Uint8) MarshalText() ([]byte, error) {
if !u.Valid {
return []byte{}, nil
}
return []byte(strconv.FormatUint(uint64(u.Uint8), 10)), nil
}
// SetValid changes this Uint8's value and also sets it to be non-null.
func (u *Uint8) SetValid(n uint8) {
u.Uint8 = n
u.Valid = true
}
// Ptr returns a pointer to this Uint8's value, or a nil pointer if this Uint8 is null.
func (u Uint8) Ptr() *uint8 {
if !u.Valid {
return nil
}
return &u.Uint8
}
// IsNull returns true for invalid Uint8's, for future omitempty support (Go 1.4?)
func (u Uint8) IsNull() bool {
return !u.Valid
}
// Scan implements the Scanner interface.
func (u *Uint8) Scan(value interface{}) error {
if value == nil {
u.Uint8, u.Valid = 0, false
return nil
}
u.Valid = true
return convert.ConvertAssign(&u.Uint8, value)
}
// Value implements the driver Valuer interface.
func (u Uint8) Value() (driver.Value, error) {
if !u.Valid {
return nil, nil
}
return int64(u.Uint8), nil
}