Bump Redigo to v1.8.2.

Signed-off-by: olegburov <oleg.burov@outlook.com>

vendor/github.com/gomodule/redigo/redis/scan.go

@@ -0,0 +1,673 @@
+// Copyright 2012 Gary Burd
+//
+// Licensed under the Apache License, Version 2.0 (the "License"): you may
+// not use this file except in compliance with the License. You may obtain
+// a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+// WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+// License for the specific language governing permissions and limitations
+// under the License.
+
+package redis
+
+import (
+	"errors"
+	"fmt"
+	"reflect"
+	"strconv"
+	"strings"
+	"sync"
+)
+
+var (
+	scannerType = reflect.TypeOf((*Scanner)(nil)).Elem()
+)
+
+func ensureLen(d reflect.Value, n int) {
+	if n > d.Cap() {
+		d.Set(reflect.MakeSlice(d.Type(), n, n))
+	} else {
+		d.SetLen(n)
+	}
+}
+
+func cannotConvert(d reflect.Value, s interface{}) error {
+	var sname string
+	switch s.(type) {
+	case string:
+		sname = "Redis simple string"
+	case Error:
+		sname = "Redis error"
+	case int64:
+		sname = "Redis integer"
+	case []byte:
+		sname = "Redis bulk string"
+	case []interface{}:
+		sname = "Redis array"
+	case nil:
+		sname = "Redis nil"
+	default:
+		sname = reflect.TypeOf(s).String()
+	}
+	return fmt.Errorf("cannot convert from %s to %s", sname, d.Type())
+}
+
+func convertAssignNil(d reflect.Value) (err error) {
+	switch d.Type().Kind() {
+	case reflect.Slice, reflect.Interface:
+		d.Set(reflect.Zero(d.Type()))
+	default:
+		err = cannotConvert(d, nil)
+	}
+	return err
+}
+
+func convertAssignError(d reflect.Value, s Error) (err error) {
+	if d.Kind() == reflect.String {
+		d.SetString(string(s))
+	} else if d.Kind() == reflect.Slice && d.Type().Elem().Kind() == reflect.Uint8 {
+		d.SetBytes([]byte(s))
+	} else {
+		err = cannotConvert(d, s)
+	}
+	return
+}
+
+func convertAssignString(d reflect.Value, s string) (err error) {
+	switch d.Type().Kind() {
+	case reflect.Float32, reflect.Float64:
+		var x float64
+		x, err = strconv.ParseFloat(s, d.Type().Bits())
+		d.SetFloat(x)
+	case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64:
+		var x int64
+		x, err = strconv.ParseInt(s, 10, d.Type().Bits())
+		d.SetInt(x)
+	case reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64:
+		var x uint64
+		x, err = strconv.ParseUint(s, 10, d.Type().Bits())
+		d.SetUint(x)
+	case reflect.Bool:
+		var x bool
+		x, err = strconv.ParseBool(s)
+		d.SetBool(x)
+	case reflect.String:
+		d.SetString(s)
+	case reflect.Slice:
+		if d.Type().Elem().Kind() == reflect.Uint8 {
+			d.SetBytes([]byte(s))
+		} else {
+			err = cannotConvert(d, s)
+		}
+	case reflect.Ptr:
+		err = convertAssignString(d.Elem(), s)
+	default:
+		err = cannotConvert(d, s)
+	}
+	return
+}
+
+func convertAssignBulkString(d reflect.Value, s []byte) (err error) {
+	switch d.Type().Kind() {
+	case reflect.Slice:
+		// Handle []byte destination here to avoid unnecessary
+		// []byte -> string -> []byte converion.
+		if d.Type().Elem().Kind() == reflect.Uint8 {
+			d.SetBytes(s)
+		} else {
+			err = cannotConvert(d, s)
+		}
+	case reflect.Ptr:
+		if d.CanInterface() && d.CanSet() {
+			if s == nil {
+				if d.IsNil() {
+					return nil
+				}
+
+				d.Set(reflect.Zero(d.Type()))
+				return nil
+			}
+
+			if d.IsNil() {
+				d.Set(reflect.New(d.Type().Elem()))
+			}
+
+			if sc, ok := d.Interface().(Scanner); ok {
+				return sc.RedisScan(s)
+			}
+		}
+		err = convertAssignString(d, string(s))
+	default:
+		err = convertAssignString(d, string(s))
+	}
+	return err
+}
+
+func convertAssignInt(d reflect.Value, s int64) (err error) {
+	switch d.Type().Kind() {
+	case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64:
+		d.SetInt(s)
+		if d.Int() != s {
+			err = strconv.ErrRange
+			d.SetInt(0)
+		}
+	case reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64:
+		if s < 0 {
+			err = strconv.ErrRange
+		} else {
+			x := uint64(s)
+			d.SetUint(x)
+			if d.Uint() != x {
+				err = strconv.ErrRange
+				d.SetUint(0)
+			}
+		}
+	case reflect.Bool:
+		d.SetBool(s != 0)
+	default:
+		err = cannotConvert(d, s)
+	}
+	return
+}
+
+func convertAssignValue(d reflect.Value, s interface{}) (err error) {
+	if d.Kind() != reflect.Ptr {
+		if d.CanAddr() {
+			d2 := d.Addr()
+			if d2.CanInterface() {
+				if scanner, ok := d2.Interface().(Scanner); ok {
+					return scanner.RedisScan(s)
+				}
+			}
+		}
+	} else if d.CanInterface() {
+		// Already a reflect.Ptr
+		if d.IsNil() {
+			d.Set(reflect.New(d.Type().Elem()))
+		}
+		if scanner, ok := d.Interface().(Scanner); ok {
+			return scanner.RedisScan(s)
+		}
+	}
+
+	switch s := s.(type) {
+	case nil:
+		err = convertAssignNil(d)
+	case []byte:
+		err = convertAssignBulkString(d, s)
+	case int64:
+		err = convertAssignInt(d, s)
+	case string:
+		err = convertAssignString(d, s)
+	case Error:
+		err = convertAssignError(d, s)
+	default:
+		err = cannotConvert(d, s)
+	}
+	return err
+}
+
+func convertAssignArray(d reflect.Value, s []interface{}) error {
+	if d.Type().Kind() != reflect.Slice {
+		return cannotConvert(d, s)
+	}
+	ensureLen(d, len(s))
+	for i := 0; i < len(s); i++ {
+		if err := convertAssignValue(d.Index(i), s[i]); err != nil {
+			return err
+		}
+	}
+	return nil
+}
+
+func convertAssign(d interface{}, s interface{}) (err error) {
+	if scanner, ok := d.(Scanner); ok {
+		return scanner.RedisScan(s)
+	}
+
+	// Handle the most common destination types using type switches and
+	// fall back to reflection for all other types.
+	switch s := s.(type) {
+	case nil:
+		// ignore
+	case []byte:
+		switch d := d.(type) {
+		case *string:
+			*d = string(s)
+		case *int:
+			*d, err = strconv.Atoi(string(s))
+		case *bool:
+			*d, err = strconv.ParseBool(string(s))
+		case *[]byte:
+			*d = s
+		case *interface{}:
+			*d = s
+		case nil:
+			// skip value
+		default:
+			if d := reflect.ValueOf(d); d.Type().Kind() != reflect.Ptr {
+				err = cannotConvert(d, s)
+			} else {
+				err = convertAssignBulkString(d.Elem(), s)
+			}
+		}
+	case int64:
+		switch d := d.(type) {
+		case *int:
+			x := int(s)
+			if int64(x) != s {
+				err = strconv.ErrRange
+				x = 0
+			}
+			*d = x
+		case *bool:
+			*d = s != 0
+		case *interface{}:
+			*d = s
+		case nil:
+			// skip value
+		default:
+			if d := reflect.ValueOf(d); d.Type().Kind() != reflect.Ptr {
+				err = cannotConvert(d, s)
+			} else {
+				err = convertAssignInt(d.Elem(), s)
+			}
+		}
+	case string:
+		switch d := d.(type) {
+		case *string:
+			*d = s
+		case *interface{}:
+			*d = s
+		case nil:
+			// skip value
+		default:
+			err = cannotConvert(reflect.ValueOf(d), s)
+		}
+	case []interface{}:
+		switch d := d.(type) {
+		case *[]interface{}:
+			*d = s
+		case *interface{}:
+			*d = s
+		case nil:
+			// skip value
+		default:
+			if d := reflect.ValueOf(d); d.Type().Kind() != reflect.Ptr {
+				err = cannotConvert(d, s)
+			} else {
+				err = convertAssignArray(d.Elem(), s)
+			}
+		}
+	case Error:
+		err = s
+	default:
+		err = cannotConvert(reflect.ValueOf(d), s)
+	}
+	return
+}
+
+// Scan copies from src to the values pointed at by dest.
+//
+// Scan uses RedisScan if available otherwise:
+//
+// The values pointed at by dest must be an integer, float, boolean, string,
+// []byte, interface{} or slices of these types. Scan uses the standard strconv
+// package to convert bulk strings to numeric and boolean types.
+//
+// If a dest value is nil, then the corresponding src value is skipped.
+//
+// If a src element is nil, then the corresponding dest value is not modified.
+//
+// To enable easy use of Scan in a loop, Scan returns the slice of src
+// following the copied values.
+func Scan(src []interface{}, dest ...interface{}) ([]interface{}, error) {
+	if len(src) < len(dest) {
+		return nil, errors.New("redigo.Scan: array short")
+	}
+	var err error
+	for i, d := range dest {
+		err = convertAssign(d, src[i])
+		if err != nil {
+			err = fmt.Errorf("redigo.Scan: cannot assign to dest %d: %v", i, err)
+			break
+		}
+	}
+	return src[len(dest):], err
+}
+
+type fieldSpec struct {
+	name      string
+	index     []int
+	omitEmpty bool
+}
+
+type structSpec struct {
+	m map[string]*fieldSpec
+	l []*fieldSpec
+}
+
+func (ss *structSpec) fieldSpec(name []byte) *fieldSpec {
+	return ss.m[string(name)]
+}
+
+func compileStructSpec(t reflect.Type, depth map[string]int, index []int, ss *structSpec) {
+	for i := 0; i < t.NumField(); i++ {
+		f := t.Field(i)
+		switch {
+		case f.PkgPath != "" && !f.Anonymous:
+			// Ignore unexported fields.
+		case f.Anonymous:
+			switch f.Type.Kind() {
+			case reflect.Struct:
+				compileStructSpec(f.Type, depth, append(index, i), ss)
+			case reflect.Ptr:
+				// TODO(steve): Protect against infinite recursion.
+				if f.Type.Elem().Kind() == reflect.Struct {
+					compileStructSpec(f.Type.Elem(), depth, append(index, i), ss)
+				}
+			}
+		default:
+			fs := &fieldSpec{name: f.Name}
+			tag := f.Tag.Get("redis")
+			p := strings.Split(tag, ",")
+			if len(p) > 0 {
+				if p[0] == "-" {
+					continue
+				}
+				if len(p[0]) > 0 {
+					fs.name = p[0]
+				}
+				for _, s := range p[1:] {
+					switch s {
+					case "omitempty":
+						fs.omitEmpty = true
+					default:
+						panic(fmt.Errorf("redigo: unknown field tag %s for type %s", s, t.Name()))
+					}
+				}
+			}
+			d, found := depth[fs.name]
+			if !found {
+				d = 1 << 30
+			}
+			switch {
+			case len(index) == d:
+				// At same depth, remove from result.
+				delete(ss.m, fs.name)
+				j := 0
+				for i := 0; i < len(ss.l); i++ {
+					if fs.name != ss.l[i].name {
+						ss.l[j] = ss.l[i]
+						j += 1
+					}
+				}
+				ss.l = ss.l[:j]
+			case len(index) < d:
+				fs.index = make([]int, len(index)+1)
+				copy(fs.index, index)
+				fs.index[len(index)] = i
+				depth[fs.name] = len(index)
+				ss.m[fs.name] = fs
+				ss.l = append(ss.l, fs)
+			}
+		}
+	}
+}
+
+var (
+	structSpecMutex  sync.RWMutex
+	structSpecCache  = make(map[reflect.Type]*structSpec)
+	defaultFieldSpec = &fieldSpec{}
+)
+
+func structSpecForType(t reflect.Type) *structSpec {
+
+	structSpecMutex.RLock()
+	ss, found := structSpecCache[t]
+	structSpecMutex.RUnlock()
+	if found {
+		return ss
+	}
+
+	structSpecMutex.Lock()
+	defer structSpecMutex.Unlock()
+	ss, found = structSpecCache[t]
+	if found {
+		return ss
+	}
+
+	ss = &structSpec{m: make(map[string]*fieldSpec)}
+	compileStructSpec(t, make(map[string]int), nil, ss)
+	structSpecCache[t] = ss
+	return ss
+}
+
+var errScanStructValue = errors.New("redigo.ScanStruct: value must be non-nil pointer to a struct")
+
+// ScanStruct scans alternating names and values from src to a struct. The
+// HGETALL and CONFIG GET commands return replies in this format.
+//
+// ScanStruct uses exported field names to match values in the response. Use
+// 'redis' field tag to override the name:
+//
+//      Field int `redis:"myName"`
+//
+// Fields with the tag redis:"-" are ignored.
+//
+// Each field uses RedisScan if available otherwise:
+// Integer, float, boolean, string and []byte fields are supported. Scan uses the
+// standard strconv package to convert bulk string values to numeric and
+// boolean types.
+//
+// If a src element is nil, then the corresponding field is not modified.
+func ScanStruct(src []interface{}, dest interface{}) error {
+	d := reflect.ValueOf(dest)
+	if d.Kind() != reflect.Ptr || d.IsNil() {
+		return errScanStructValue
+	}
+	d = d.Elem()
+	if d.Kind() != reflect.Struct {
+		return errScanStructValue
+	}
+	ss := structSpecForType(d.Type())
+
+	if len(src)%2 != 0 {
+		return errors.New("redigo.ScanStruct: number of values not a multiple of 2")
+	}
+
+	for i := 0; i < len(src); i += 2 {
+		s := src[i+1]
+		if s == nil {
+			continue
+		}
+		name, ok := src[i].([]byte)
+		if !ok {
+			return fmt.Errorf("redigo.ScanStruct: key %d not a bulk string value", i)
+		}
+		fs := ss.fieldSpec(name)
+		if fs == nil {
+			continue
+		}
+		if err := convertAssignValue(d.FieldByIndex(fs.index), s); err != nil {
+			return fmt.Errorf("redigo.ScanStruct: cannot assign field %s: %v", fs.name, err)
+		}
+	}
+	return nil
+}
+
+var (
+	errScanSliceValue = errors.New("redigo.ScanSlice: dest must be non-nil pointer to a struct")
+)
+
+// ScanSlice scans src to the slice pointed to by dest.
+//
+// If the target is a slice of types which implement Scanner then the custom
+// RedisScan method is used otherwise the following rules apply:
+//
+// The elements in the dest slice must be integer, float, boolean, string, struct
+// or pointer to struct values.
+//
+// Struct fields must be integer, float, boolean or string values. All struct
+// fields are used unless a subset is specified using fieldNames.
+func ScanSlice(src []interface{}, dest interface{}, fieldNames ...string) error {
+	d := reflect.ValueOf(dest)
+	if d.Kind() != reflect.Ptr || d.IsNil() {
+		return errScanSliceValue
+	}
+	d = d.Elem()
+	if d.Kind() != reflect.Slice {
+		return errScanSliceValue
+	}
+
+	isPtr := false
+	t := d.Type().Elem()
+	st := t
+	if t.Kind() == reflect.Ptr && t.Elem().Kind() == reflect.Struct {
+		isPtr = true
+		t = t.Elem()
+	}
+
+	if t.Kind() != reflect.Struct || st.Implements(scannerType) {
+		ensureLen(d, len(src))
+		for i, s := range src {
+			if s == nil {
+				continue
+			}
+			if err := convertAssignValue(d.Index(i), s); err != nil {
+				return fmt.Errorf("redigo.ScanSlice: cannot assign element %d: %v", i, err)
+			}
+		}
+		return nil
+	}
+
+	ss := structSpecForType(t)
+	fss := ss.l
+	if len(fieldNames) > 0 {
+		fss = make([]*fieldSpec, len(fieldNames))
+		for i, name := range fieldNames {
+			fss[i] = ss.m[name]
+			if fss[i] == nil {
+				return fmt.Errorf("redigo.ScanSlice: ScanSlice bad field name %s", name)
+			}
+		}
+	}
+
+	if len(fss) == 0 {
+		return errors.New("redigo.ScanSlice: no struct fields")
+	}
+
+	n := len(src) / len(fss)
+	if n*len(fss) != len(src) {
+		return errors.New("redigo.ScanSlice: length not a multiple of struct field count")
+	}
+
+	ensureLen(d, n)
+	for i := 0; i < n; i++ {
+		d := d.Index(i)
+		if isPtr {
+			if d.IsNil() {
+				d.Set(reflect.New(t))
+			}
+			d = d.Elem()
+		}
+		for j, fs := range fss {
+			s := src[i*len(fss)+j]
+			if s == nil {
+				continue
+			}
+			if err := convertAssignValue(d.FieldByIndex(fs.index), s); err != nil {
+				return fmt.Errorf("redigo.ScanSlice: cannot assign element %d to field %s: %v", i*len(fss)+j, fs.name, err)
+			}
+		}
+	}
+	return nil
+}
+
+// Args is a helper for constructing command arguments from structured values.
+type Args []interface{}
+
+// Add returns the result of appending value to args.
+func (args Args) Add(value ...interface{}) Args {
+	return append(args, value...)
+}
+
+// AddFlat returns the result of appending the flattened value of v to args.
+//
+// Maps are flattened by appending the alternating keys and map values to args.
+//
+// Slices are flattened by appending the slice elements to args.
+//
+// Structs are flattened by appending the alternating names and values of
+// exported fields to args. If v is a nil struct pointer, then nothing is
+// appended. The 'redis' field tag overrides struct field names. See ScanStruct
+// for more information on the use of the 'redis' field tag.
+//
+// Other types are appended to args as is.
+func (args Args) AddFlat(v interface{}) Args {
+	rv := reflect.ValueOf(v)
+	switch rv.Kind() {
+	case reflect.Struct:
+		args = flattenStruct(args, rv)
+	case reflect.Slice:
+		for i := 0; i < rv.Len(); i++ {
+			args = append(args, rv.Index(i).Interface())
+		}
+	case reflect.Map:
+		for _, k := range rv.MapKeys() {
+			args = append(args, k.Interface(), rv.MapIndex(k).Interface())
+		}
+	case reflect.Ptr:
+		if rv.Type().Elem().Kind() == reflect.Struct {
+			if !rv.IsNil() {
+				args = flattenStruct(args, rv.Elem())
+			}
+		} else {
+			args = append(args, v)
+		}
+	default:
+		args = append(args, v)
+	}
+	return args
+}
+
+func flattenStruct(args Args, v reflect.Value) Args {
+	ss := structSpecForType(v.Type())
+	for _, fs := range ss.l {
+		fv := v.FieldByIndex(fs.index)
+		if fs.omitEmpty {
+			var empty = false
+			switch fv.Kind() {
+			case reflect.Array, reflect.Map, reflect.Slice, reflect.String:
+				empty = fv.Len() == 0
+			case reflect.Bool:
+				empty = !fv.Bool()
+			case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64:
+				empty = fv.Int() == 0
+			case reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64, reflect.Uintptr:
+				empty = fv.Uint() == 0
+			case reflect.Float32, reflect.Float64:
+				empty = fv.Float() == 0
+			case reflect.Interface, reflect.Ptr:
+				empty = fv.IsNil()
+			}
+			if empty {
+				continue
+			}
+		}
+		if arg, ok := fv.Interface().(Argument); ok {
+			args = append(args, fs.name, arg.RedisArg())
+		} else if fv.Kind() == reflect.Ptr {
+			if !fv.IsNil() {
+				args = append(args, fs.name, fv.Elem().Interface())
+			}
+		} else {
+			args = append(args, fs.name, fv.Interface())
+		}
+	}
+	return args
+}