database/sql: add NullInt16 and NullByte

Fixes #40082

Change-Id: I01cd4d0e23c0376a6ee6e0b196c9f840cd662325
Reviewed-on: https://go-review.googlesource.com/c/go/+/311572
Reviewed-by: Emmanuel Odeke <emmanuel@orijtech.com>
Reviewed-by: Daniel Theophanes <kardianos@gmail.com>
Run-TryBot: Emmanuel Odeke <emmanuel@orijtech.com>
TryBot-Result: Go Bot <gobot@golang.org>

src/database/sql/fakedb_test.go

@@ -1186,9 +1186,11 @@ func converterForType(typ string) driver.ValueConverter {
 		return driver.Bool
 	case "nullbool":
 		return driver.Null{Converter: driver.Bool}
+	case "byte", "int16":
+		return driver.NotNull{Converter: driver.DefaultParameterConverter}
 	case "int32":
 		return driver.Int32
-	case "nullint32":
+	case "nullbyte", "nullint32", "nullint16":
 		return driver.Null{Converter: driver.DefaultParameterConverter}
 	case "string":
 		return driver.NotNull{Converter: fakeDriverString{}}
@@ -1222,6 +1224,10 @@ func colTypeToReflectType(typ string) reflect.Type {
 		return reflect.TypeOf(false)
 	case "nullbool":
 		return reflect.TypeOf(NullBool{})
+	case "int16":
+		return reflect.TypeOf(int16(0))
+	case "nullint16":
+		return reflect.TypeOf(NullInt16{})
 	case "int32":
 		return reflect.TypeOf(int32(0))
 	case "nullint32":

src/database/sql/sql.go

@@ -260,6 +260,60 @@ func (n NullInt32) Value() (driver.Value, error) {
 	return int64(n.Int32), nil
 }
 
+// NullInt16 represents an int16 that may be null.
+// NullInt16 implements the Scanner interface so
+// it can be used as a scan destination, similar to NullString.
+type NullInt16 struct {
+	Int16 int16
+	Valid bool // Valid is true if Int16 is not NULL
+}
+
+// Scan implements the Scanner interface.
+func (n *NullInt16) Scan(value interface{}) error {
+	if value == nil {
+		n.Int16, n.Valid = 0, false
+		return nil
+	}
+	err := convertAssign(&n.Int16, value)
+	n.Valid = err == nil
+	return err
+}
+
+// Value implements the driver Valuer interface.
+func (n NullInt16) Value() (driver.Value, error) {
+	if !n.Valid {
+		return nil, nil
+	}
+	return int64(n.Int16), nil
+}
+
+// NullByte represents a byte that may be null.
+// NullByte implements the Scanner interface so
+// it can be used as a scan destination, similar to NullString.
+type NullByte struct {
+	Byte  byte
+	Valid bool // Valid is true if Byte is not NULL
+}
+
+// Scan implements the Scanner interface.
+func (n *NullByte) Scan(value interface{}) error {
+	if value == nil {
+		n.Byte, n.Valid = 0, false
+		return nil
+	}
+	err := convertAssign(&n.Byte, value)
+	n.Valid = err == nil
+	return err
+}
+
+// Value implements the driver Valuer interface.
+func (n NullByte) Value() (driver.Value, error) {
+	if !n.Valid {
+		return nil, nil
+	}
+	return int64(n.Byte), nil
+}
+
 // NullFloat64 represents a float64 that may be null.
 // NullFloat64 implements the Scanner interface so
 // it can be used as a scan destination, similar to NullString.

src/database/sql/sql_test.go

@@ -1819,6 +1819,30 @@ func TestNullInt32Param(t *testing.T) {
 	nullTestRun(t, spec)
 }
 
+func TestNullInt16Param(t *testing.T) {
+	spec := nullTestSpec{"nullint16", "int16", [6]nullTestRow{
+		{NullInt16{31, true}, 1, NullInt16{31, true}},
+		{NullInt16{-22, false}, 1, NullInt16{0, false}},
+		{22, 1, NullInt16{22, true}},
+		{NullInt16{33, true}, 1, NullInt16{33, true}},
+		{NullInt16{222, false}, 1, NullInt16{0, false}},
+		{0, NullInt16{31, false}, nil},
+	}}
+	nullTestRun(t, spec)
+}
+
+func TestNullByteParam(t *testing.T) {
+	spec := nullTestSpec{"nullbyte", "byte", [6]nullTestRow{
+		{NullByte{31, true}, 1, NullByte{31, true}},
+		{NullByte{0, false}, 1, NullByte{0, false}},
+		{22, 1, NullByte{22, true}},
+		{NullByte{33, true}, 1, NullByte{33, true}},
+		{NullByte{222, false}, 1, NullByte{0, false}},
+		{0, NullByte{31, false}, nil},
+	}}
+	nullTestRun(t, spec)
+}
+
 func TestNullFloat64Param(t *testing.T) {
 	spec := nullTestSpec{"nullfloat64", "float64", [6]nullTestRow{
 		{NullFloat64{31.2, true}, 1, NullFloat64{31.2, true}},