feat(bun): generate native Go array slices for PostgreSQL array columns

Bun's pgdialect scans/appends native slices directly, so array columns (text[], integer[], uuid[], ...) always generate as plain []string, []int32, etc. with an explicit "array" bun tag, regardless of --types (sqltypes/stdlib/baselib). The SqlXxxArray wrapper types are no longer used for Bun array columns (gorm is unaffected and keeps using them). Adds --array-nullable pointer_slice to represent nullable array columns as *[]T instead of []T, so callers can distinguish SQL NULL (nil) from '{}' (pointer to an empty slice). Verified end-to-end against a live PostgreSQL instance for NULL/{}/populated arrays in every --types mode. Closes #13
2026-07-21 12:41:38 +02:00
parent 2cecb4c11c
commit 5d9ff5df03
65 changed files with 9584 additions and 167 deletions
@@ -0,0 +1,608 @@
+package pgdialect
+
+import (
+	"database/sql"
+	"database/sql/driver"
+	"fmt"
+	"math"
+	"reflect"
+	"strconv"
+	"time"
+
+	"github.com/uptrace/bun/dialect"
+	"github.com/uptrace/bun/internal"
+	"github.com/uptrace/bun/schema"
+)
+
+type ArrayValue struct {
+	v reflect.Value
+
+	append schema.AppenderFunc
+	scan   schema.ScannerFunc
+}
+
+// Array accepts a slice and returns a wrapper for working with PostgreSQL
+// array data type.
+//
+// For struct fields you can use array tag:
+//
+//	Emails  []string `bun:",array"`
+func Array(vi any) *ArrayValue {
+	v := reflect.ValueOf(vi)
+	if !v.IsValid() {
+		panic(fmt.Errorf("bun: Array(nil)"))
+	}
+
+	return &ArrayValue{
+		v: v,
+
+		append: pgDialect.arrayAppender(v.Type()),
+		scan:   arrayScanner(v.Type()),
+	}
+}
+
+var (
+	_ schema.QueryAppender = (*ArrayValue)(nil)
+	_ sql.Scanner          = (*ArrayValue)(nil)
+)
+
+func (a *ArrayValue) AppendQuery(gen schema.QueryGen, b []byte) ([]byte, error) {
+	if a.append == nil {
+		panic(fmt.Errorf("bun: Array(unsupported %s)", a.v.Type()))
+	}
+	return a.append(gen, b, a.v), nil
+}
+
+func (a *ArrayValue) Scan(src any) error {
+	if a.scan == nil {
+		return fmt.Errorf("bun: Array(unsupported %s)", a.v.Type())
+	}
+	if a.v.Kind() != reflect.Ptr {
+		return fmt.Errorf("bun: Array(non-pointer %s)", a.v.Type())
+	}
+	return a.scan(a.v, src)
+}
+
+func (a *ArrayValue) Value() any {
+	if a.v.IsValid() {
+		return a.v.Interface()
+	}
+	return nil
+}
+
+//------------------------------------------------------------------------------
+
+func (d *Dialect) arrayAppender(typ reflect.Type) schema.AppenderFunc {
+	kind := typ.Kind()
+
+	switch kind {
+	case reflect.Ptr:
+		if fn := d.arrayAppender(typ.Elem()); fn != nil {
+			return schema.PtrAppender(fn)
+		}
+	case reflect.Slice, reflect.Array:
+		// continue below
+	default:
+		return nil
+	}
+
+	elemType := typ.Elem()
+
+	if kind == reflect.Slice {
+		switch elemType {
+		case stringType:
+			return appendStringSliceValue
+		case intType:
+			return appendIntSliceValue
+		case int64Type:
+			return appendInt64SliceValue
+		case float64Type:
+			return appendFloat64SliceValue
+		case timeType:
+			return appendTimeSliceValue
+		}
+	}
+
+	appendElem := d.arrayElemAppender(elemType)
+	if appendElem == nil {
+		panic(fmt.Errorf("pgdialect: %s is not supported", typ))
+	}
+
+	return func(gen schema.QueryGen, b []byte, v reflect.Value) []byte {
+		kind := v.Kind()
+		switch kind {
+		case reflect.Ptr, reflect.Slice:
+			if v.IsNil() {
+				return dialect.AppendNull(b)
+			}
+		}
+
+		if kind == reflect.Ptr {
+			v = v.Elem()
+		}
+
+		b = append(b, "'{"...)
+
+		ln := v.Len()
+		for i := 0; i < ln; i++ {
+			elem := v.Index(i)
+			if i > 0 {
+				b = append(b, ',')
+			}
+			b = appendElem(gen, b, elem)
+		}
+
+		b = append(b, "}'"...)
+
+		return b
+	}
+}
+
+func (d *Dialect) arrayElemAppender(typ reflect.Type) schema.AppenderFunc {
+	if typ.Implements(driverValuerType) {
+		return arrayAppendDriverValue
+	}
+	if typ == timeType {
+		return appendTimeElemValue
+	}
+
+	switch typ.Kind() {
+	case reflect.String:
+		return appendStringElemValue
+	case reflect.Slice:
+		if typ.Elem().Kind() == reflect.Uint8 {
+			return appendBytesElemValue
+		}
+	case reflect.Ptr:
+		return schema.PtrAppender(d.arrayElemAppender(typ.Elem()))
+	}
+	return schema.Appender(d, typ)
+}
+
+func appendTimeElemValue(gen schema.QueryGen, b []byte, v reflect.Value) []byte {
+	ts := v.Convert(timeType).Interface().(time.Time)
+
+	b = append(b, '"')
+	b = appendTime(b, ts)
+	return append(b, '"')
+}
+
+func appendStringElemValue(gen schema.QueryGen, b []byte, v reflect.Value) []byte {
+	return appendStringElem(b, v.String())
+}
+
+func appendBytesElemValue(gen schema.QueryGen, b []byte, v reflect.Value) []byte {
+	return appendBytesElem(b, v.Bytes())
+}
+
+func arrayAppendDriverValue(gen schema.QueryGen, b []byte, v reflect.Value) []byte {
+	iface, err := v.Interface().(driver.Valuer).Value()
+	if err != nil {
+		return dialect.AppendError(b, err)
+	}
+	return appendElem(b, iface)
+}
+
+func appendStringSliceValue(gen schema.QueryGen, b []byte, v reflect.Value) []byte {
+	ss := v.Convert(sliceStringType).Interface().([]string)
+	return appendStringSlice(b, ss)
+}
+
+func appendStringSlice(b []byte, ss []string) []byte {
+	if ss == nil {
+		return dialect.AppendNull(b)
+	}
+
+	b = append(b, '\'')
+
+	b = append(b, '{')
+	for _, s := range ss {
+		b = appendStringElem(b, s)
+		b = append(b, ',')
+	}
+	if len(ss) > 0 {
+		b[len(b)-1] = '}' // Replace trailing comma.
+	} else {
+		b = append(b, '}')
+	}
+
+	b = append(b, '\'')
+
+	return b
+}
+
+func appendIntSliceValue(gen schema.QueryGen, b []byte, v reflect.Value) []byte {
+	ints := v.Convert(sliceIntType).Interface().([]int)
+	return appendIntSlice(b, ints)
+}
+
+func appendIntSlice(b []byte, ints []int) []byte {
+	if ints == nil {
+		return dialect.AppendNull(b)
+	}
+
+	b = append(b, '\'')
+
+	b = append(b, '{')
+	for _, n := range ints {
+		b = strconv.AppendInt(b, int64(n), 10)
+		b = append(b, ',')
+	}
+	if len(ints) > 0 {
+		b[len(b)-1] = '}' // Replace trailing comma.
+	} else {
+		b = append(b, '}')
+	}
+
+	b = append(b, '\'')
+
+	return b
+}
+
+func appendInt64SliceValue(gen schema.QueryGen, b []byte, v reflect.Value) []byte {
+	ints := v.Convert(sliceInt64Type).Interface().([]int64)
+	return appendInt64Slice(b, ints)
+}
+
+func appendInt64Slice(b []byte, ints []int64) []byte {
+	if ints == nil {
+		return dialect.AppendNull(b)
+	}
+
+	b = append(b, '\'')
+
+	b = append(b, '{')
+	for _, n := range ints {
+		b = strconv.AppendInt(b, n, 10)
+		b = append(b, ',')
+	}
+	if len(ints) > 0 {
+		b[len(b)-1] = '}' // Replace trailing comma.
+	} else {
+		b = append(b, '}')
+	}
+
+	b = append(b, '\'')
+
+	return b
+}
+
+func appendFloat64SliceValue(gen schema.QueryGen, b []byte, v reflect.Value) []byte {
+	floats := v.Convert(sliceFloat64Type).Interface().([]float64)
+	return appendFloat64Slice(b, floats)
+}
+
+func appendFloat64Slice(b []byte, floats []float64) []byte {
+	if floats == nil {
+		return dialect.AppendNull(b)
+	}
+
+	b = append(b, '\'')
+
+	b = append(b, '{')
+	for _, n := range floats {
+		b = arrayAppendFloat64(b, n)
+		b = append(b, ',')
+	}
+	if len(floats) > 0 {
+		b[len(b)-1] = '}' // Replace trailing comma.
+	} else {
+		b = append(b, '}')
+	}
+
+	b = append(b, '\'')
+
+	return b
+}
+
+func arrayAppendFloat64(b []byte, num float64) []byte {
+	switch {
+	case math.IsNaN(num):
+		return append(b, "NaN"...)
+	case math.IsInf(num, 1):
+		return append(b, "Infinity"...)
+	case math.IsInf(num, -1):
+		return append(b, "-Infinity"...)
+	default:
+		return strconv.AppendFloat(b, num, 'f', -1, 64)
+	}
+}
+
+func appendTimeSliceValue(gen schema.QueryGen, b []byte, v reflect.Value) []byte {
+	ts := v.Convert(sliceTimeType).Interface().([]time.Time)
+	return appendTimeSlice(gen, b, ts)
+}
+
+func appendTimeSlice(gen schema.QueryGen, b []byte, ts []time.Time) []byte {
+	if ts == nil {
+		return dialect.AppendNull(b)
+	}
+	b = append(b, '\'')
+	b = append(b, '{')
+	for _, t := range ts {
+		b = append(b, '"')
+		b = appendTime(b, t)
+		b = append(b, '"')
+		b = append(b, ',')
+	}
+	if len(ts) > 0 {
+		b[len(b)-1] = '}' // Replace trailing comma.
+	} else {
+		b = append(b, '}')
+	}
+	b = append(b, '\'')
+	return b
+}
+
+//------------------------------------------------------------------------------
+
+func arrayScanner(typ reflect.Type) schema.ScannerFunc {
+	kind := typ.Kind()
+
+	switch kind {
+	case reflect.Ptr:
+		if fn := arrayScanner(typ.Elem()); fn != nil {
+			return schema.PtrScanner(fn)
+		}
+	case reflect.Slice, reflect.Array:
+		// ok:
+	default:
+		return nil
+	}
+
+	elemType := typ.Elem()
+
+	if kind == reflect.Slice {
+		switch elemType {
+		case stringType:
+			return scanStringSliceValue
+		case intType:
+			return scanIntSliceValue
+		case int64Type:
+			return scanInt64SliceValue
+		case float64Type:
+			return scanFloat64SliceValue
+		}
+	}
+
+	scanElem := schema.Scanner(elemType)
+	return func(dest reflect.Value, src any) error {
+		dest = reflect.Indirect(dest)
+		if !dest.CanSet() {
+			return fmt.Errorf("bun: Scan(non-settable %s)", dest.Type())
+		}
+
+		kind := dest.Kind()
+
+		if src == nil {
+			if kind != reflect.Slice || !dest.IsNil() {
+				dest.Set(reflect.Zero(dest.Type()))
+			}
+			return nil
+		}
+
+		if kind == reflect.Slice {
+			if dest.IsNil() {
+				dest.Set(reflect.MakeSlice(dest.Type(), 0, 0))
+			} else if dest.Len() > 0 {
+				dest.Set(dest.Slice(0, 0))
+			}
+		}
+
+		if src == nil {
+			return nil
+		}
+
+		b, err := toBytes(src)
+		if err != nil {
+			return err
+		}
+
+		p := newArrayParser(b)
+		nextValue := internal.MakeSliceNextElemFunc(dest)
+		for p.Next() {
+			elem := p.Elem()
+			elemValue := nextValue()
+			if err := scanElem(elemValue, elem); err != nil {
+				return fmt.Errorf("scanElem failed: %w", err)
+			}
+		}
+		return p.Err()
+	}
+}
+
+func scanStringSliceValue(dest reflect.Value, src any) error {
+	dest = reflect.Indirect(dest)
+	if !dest.CanSet() {
+		return fmt.Errorf("bun: Scan(non-settable %s)", dest.Type())
+	}
+
+	slice, err := decodeStringSlice(src)
+	if err != nil {
+		return err
+	}
+
+	dest.Set(reflect.ValueOf(slice))
+	return nil
+}
+
+func decodeStringSlice(src any) ([]string, error) {
+	if src == nil {
+		return nil, nil
+	}
+
+	b, err := toBytes(src)
+	if err != nil {
+		return nil, err
+	}
+
+	slice := make([]string, 0)
+
+	p := newArrayParser(b)
+	for p.Next() {
+		elem := p.Elem()
+		slice = append(slice, string(elem))
+	}
+	if err := p.Err(); err != nil {
+		return nil, err
+	}
+	return slice, nil
+}
+
+func scanIntSliceValue(dest reflect.Value, src any) error {
+	dest = reflect.Indirect(dest)
+	if !dest.CanSet() {
+		return fmt.Errorf("bun: Scan(non-settable %s)", dest.Type())
+	}
+
+	slice, err := decodeIntSlice(src)
+	if err != nil {
+		return err
+	}
+
+	dest.Set(reflect.ValueOf(slice))
+	return nil
+}
+
+func decodeIntSlice(src any) ([]int, error) {
+	if src == nil {
+		return nil, nil
+	}
+
+	b, err := toBytes(src)
+	if err != nil {
+		return nil, err
+	}
+
+	slice := make([]int, 0)
+
+	p := newArrayParser(b)
+	for p.Next() {
+		elem := p.Elem()
+
+		if elem == nil {
+			slice = append(slice, 0)
+			continue
+		}
+
+		n, err := strconv.Atoi(internal.String(elem))
+		if err != nil {
+			return nil, err
+		}
+
+		slice = append(slice, n)
+	}
+	if err := p.Err(); err != nil {
+		return nil, err
+	}
+	return slice, nil
+}
+
+func scanInt64SliceValue(dest reflect.Value, src any) error {
+	dest = reflect.Indirect(dest)
+	if !dest.CanSet() {
+		return fmt.Errorf("bun: Scan(non-settable %s)", dest.Type())
+	}
+
+	slice, err := decodeInt64Slice(src)
+	if err != nil {
+		return err
+	}
+
+	dest.Set(reflect.ValueOf(slice))
+	return nil
+}
+
+func decodeInt64Slice(src any) ([]int64, error) {
+	if src == nil {
+		return nil, nil
+	}
+
+	b, err := toBytes(src)
+	if err != nil {
+		return nil, err
+	}
+
+	slice := make([]int64, 0)
+
+	p := newArrayParser(b)
+	for p.Next() {
+		elem := p.Elem()
+
+		if elem == nil {
+			slice = append(slice, 0)
+			continue
+		}
+
+		n, err := strconv.ParseInt(internal.String(elem), 10, 64)
+		if err != nil {
+			return nil, err
+		}
+
+		slice = append(slice, n)
+	}
+	if err := p.Err(); err != nil {
+		return nil, err
+	}
+	return slice, nil
+}
+
+func scanFloat64SliceValue(dest reflect.Value, src any) error {
+	dest = reflect.Indirect(dest)
+	if !dest.CanSet() {
+		return fmt.Errorf("bun: Scan(non-settable %s)", dest.Type())
+	}
+
+	slice, err := scanFloat64Slice(src)
+	if err != nil {
+		return err
+	}
+
+	dest.Set(reflect.ValueOf(slice))
+	return nil
+}
+
+func scanFloat64Slice(src any) ([]float64, error) {
+	if src == nil {
+		return nil, nil
+	}
+
+	b, err := toBytes(src)
+	if err != nil {
+		return nil, err
+	}
+
+	slice := make([]float64, 0)
+
+	p := newArrayParser(b)
+	for p.Next() {
+		elem := p.Elem()
+
+		if elem == nil {
+			slice = append(slice, 0)
+			continue
+		}
+
+		n, err := strconv.ParseFloat(internal.String(elem), 64)
+		if err != nil {
+			return nil, err
+		}
+
+		slice = append(slice, n)
+	}
+	if err := p.Err(); err != nil {
+		return nil, err
+	}
+	return slice, nil
+}
+
+func toBytes(src any) ([]byte, error) {
+	switch src := src.(type) {
+	case string:
+		return internal.Bytes(src), nil
+	case []byte:
+		return src, nil
+	default:
+		return nil, fmt.Errorf("pgdialect: got %T, wanted []byte or string", src)
+	}
+}