1 files changed, 309 insertions, 0 deletions
diff --git a/vendor/go.mongodb.org/mongo-driver/bson/bsoncodec/map_codec.go b/vendor/go.mongodb.org/mongo-driver/bson/bsoncodec/map_codec.go
new file mode 100644
index 000000000..e1fbef9c6
--- /dev/null
+++ b/vendor/go.mongodb.org/mongo-driver/bson/bsoncodec/map_codec.go
@@ -0,0 +1,309 @@
+// Copyright (C) MongoDB, Inc. 2017-present.
+//
+// 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
+
+package bsoncodec
+
+import (
+	"encoding"
+	"fmt"
+	"reflect"
+	"strconv"
+
+	"go.mongodb.org/mongo-driver/bson/bsonoptions"
+	"go.mongodb.org/mongo-driver/bson/bsonrw"
+	"go.mongodb.org/mongo-driver/bson/bsontype"
+)
+
+var defaultMapCodec = NewMapCodec()
+
+// MapCodec is the Codec used for map values.
+type MapCodec struct {
+	DecodeZerosMap         bool
+	EncodeNilAsEmpty       bool
+	EncodeKeysWithStringer bool
+}
+
+var _ ValueCodec = &MapCodec{}
+
+// KeyMarshaler is the interface implemented by an object that can marshal itself into a string key.
+// This applies to types used as map keys and is similar to encoding.TextMarshaler.
+type KeyMarshaler interface {
+	MarshalKey() (key string, err error)
+}
+
+// KeyUnmarshaler is the interface implemented by an object that can unmarshal a string representation
+// of itself. This applies to types used as map keys and is similar to encoding.TextUnmarshaler.
+//
+// UnmarshalKey must be able to decode the form generated by MarshalKey.
+// UnmarshalKey must copy the text if it wishes to retain the text
+// after returning.
+type KeyUnmarshaler interface {
+	UnmarshalKey(key string) error
+}
+
+// NewMapCodec returns a MapCodec with options opts.
+func NewMapCodec(opts ...*bsonoptions.MapCodecOptions) *MapCodec {
+	mapOpt := bsonoptions.MergeMapCodecOptions(opts...)
+
+	codec := MapCodec{}
+	if mapOpt.DecodeZerosMap != nil {
+		codec.DecodeZerosMap = *mapOpt.DecodeZerosMap
+	}
+	if mapOpt.EncodeNilAsEmpty != nil {
+		codec.EncodeNilAsEmpty = *mapOpt.EncodeNilAsEmpty
+	}
+	if mapOpt.EncodeKeysWithStringer != nil {
+		codec.EncodeKeysWithStringer = *mapOpt.EncodeKeysWithStringer
+	}
+	return &codec
+}
+
+// EncodeValue is the ValueEncoder for map[*]* types.
+func (mc *MapCodec) EncodeValue(ec EncodeContext, vw bsonrw.ValueWriter, val reflect.Value) error {
+	if !val.IsValid() || val.Kind() != reflect.Map {
+		return ValueEncoderError{Name: "MapEncodeValue", Kinds: []reflect.Kind{reflect.Map}, Received: val}
+	}
+
+	if val.IsNil() && !mc.EncodeNilAsEmpty {
+		// If we have a nil map but we can't WriteNull, that means we're probably trying to encode
+		// to a TopLevel document. We can't currently tell if this is what actually happened, but if
+		// there's a deeper underlying problem, the error will also be returned from WriteDocument,
+		// so just continue. The operations on a map reflection value are valid, so we can call
+		// MapKeys within mapEncodeValue without a problem.
+		err := vw.WriteNull()
+		if err == nil {
+			return nil
+		}
+	}
+
+	dw, err := vw.WriteDocument()
+	if err != nil {
+		return err
+	}
+
+	return mc.mapEncodeValue(ec, dw, val, nil)
+}
+
+// mapEncodeValue handles encoding of the values of a map. The collisionFn returns
+// true if the provided key exists, this is mainly used for inline maps in the
+// struct codec.
+func (mc *MapCodec) mapEncodeValue(ec EncodeContext, dw bsonrw.DocumentWriter, val reflect.Value, collisionFn func(string) bool) error {
+
+	elemType := val.Type().Elem()
+	encoder, err := ec.LookupEncoder(elemType)
+	if err != nil && elemType.Kind() != reflect.Interface {
+		return err
+	}
+
+	keys := val.MapKeys()
+	for _, key := range keys {
+		keyStr, err := mc.encodeKey(key)
+		if err != nil {
+			return err
+		}
+
+		if collisionFn != nil && collisionFn(keyStr) {
+			return fmt.Errorf("Key %s of inlined map conflicts with a struct field name", key)
+		}
+
+		currEncoder, currVal, lookupErr := defaultValueEncoders.lookupElementEncoder(ec, encoder, val.MapIndex(key))
+		if lookupErr != nil && lookupErr != errInvalidValue {
+			return lookupErr
+		}
+
+		vw, err := dw.WriteDocumentElement(keyStr)
+		if err != nil {
+			return err
+		}
+
+		if lookupErr == errInvalidValue {
+			err = vw.WriteNull()
+			if err != nil {
+				return err
+			}
+			continue
+		}
+
+		err = currEncoder.EncodeValue(ec, vw, currVal)
+		if err != nil {
+			return err
+		}
+	}
+
+	return dw.WriteDocumentEnd()
+}
+
+// DecodeValue is the ValueDecoder for map[string/decimal]* types.
+func (mc *MapCodec) DecodeValue(dc DecodeContext, vr bsonrw.ValueReader, val reflect.Value) error {
+	if val.Kind() != reflect.Map || (!val.CanSet() && val.IsNil()) {
+		return ValueDecoderError{Name: "MapDecodeValue", Kinds: []reflect.Kind{reflect.Map}, Received: val}
+	}
+
+	switch vrType := vr.Type(); vrType {
+	case bsontype.Type(0), bsontype.EmbeddedDocument:
+	case bsontype.Null:
+		val.Set(reflect.Zero(val.Type()))
+		return vr.ReadNull()
+	case bsontype.Undefined:
+		val.Set(reflect.Zero(val.Type()))
+		return vr.ReadUndefined()
+	default:
+		return fmt.Errorf("cannot decode %v into a %s", vrType, val.Type())
+	}
+
+	dr, err := vr.ReadDocument()
+	if err != nil {
+		return err
+	}
+
+	if val.IsNil() {
+		val.Set(reflect.MakeMap(val.Type()))
+	}
+
+	if val.Len() > 0 && mc.DecodeZerosMap {
+		clearMap(val)
+	}
+
+	eType := val.Type().Elem()
+	decoder, err := dc.LookupDecoder(eType)
+	if err != nil {
+		return err
+	}
+	eTypeDecoder, _ := decoder.(typeDecoder)
+
+	if eType == tEmpty {
+		dc.Ancestor = val.Type()
+	}
+
+	keyType := val.Type().Key()
+
+	for {
+		key, vr, err := dr.ReadElement()
+		if err == bsonrw.ErrEOD {
+			break
+		}
+		if err != nil {
+			return err
+		}
+
+		k, err := mc.decodeKey(key, keyType)
+		if err != nil {
+			return err
+		}
+
+		elem, err := decodeTypeOrValueWithInfo(decoder, eTypeDecoder, dc, vr, eType, true)
+		if err != nil {
+			return newDecodeError(key, err)
+		}
+
+		val.SetMapIndex(k, elem)
+	}
+	return nil
+}
+
+func clearMap(m reflect.Value) {
+	var none reflect.Value
+	for _, k := range m.MapKeys() {
+		m.SetMapIndex(k, none)
+	}
+}
+
+func (mc *MapCodec) encodeKey(val reflect.Value) (string, error) {
+	if mc.EncodeKeysWithStringer {
+		return fmt.Sprint(val), nil
+	}
+
+	// keys of any string type are used directly
+	if val.Kind() == reflect.String {
+		return val.String(), nil
+	}
+	// KeyMarshalers are marshaled
+	if km, ok := val.Interface().(KeyMarshaler); ok {
+		if val.Kind() == reflect.Ptr && val.IsNil() {
+			return "", nil
+		}
+		buf, err := km.MarshalKey()
+		if err == nil {
+			return buf, nil
+		}
+		return "", err
+	}
+	// keys implement encoding.TextMarshaler are marshaled.
+	if km, ok := val.Interface().(encoding.TextMarshaler); ok {
+		if val.Kind() == reflect.Ptr && val.IsNil() {
+			return "", nil
+		}
+
+		buf, err := km.MarshalText()
+		if err != nil {
+			return "", err
+		}
+
+		return string(buf), nil
+	}
+
+	switch val.Kind() {
+	case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64:
+		return strconv.FormatInt(val.Int(), 10), nil
+	case reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64, reflect.Uintptr:
+		return strconv.FormatUint(val.Uint(), 10), nil
+	}
+	return "", fmt.Errorf("unsupported key type: %v", val.Type())
+}
+
+var keyUnmarshalerType = reflect.TypeOf((*KeyUnmarshaler)(nil)).Elem()
+var textUnmarshalerType = reflect.TypeOf((*encoding.TextUnmarshaler)(nil)).Elem()
+
+func (mc *MapCodec) decodeKey(key string, keyType reflect.Type) (reflect.Value, error) {
+	keyVal := reflect.ValueOf(key)
+	var err error
+	switch {
+	// First, if EncodeKeysWithStringer is not enabled, try to decode withKeyUnmarshaler
+	case !mc.EncodeKeysWithStringer && reflect.PtrTo(keyType).Implements(keyUnmarshalerType):
+		keyVal = reflect.New(keyType)
+		v := keyVal.Interface().(KeyUnmarshaler)
+		err = v.UnmarshalKey(key)
+		keyVal = keyVal.Elem()
+	// Try to decode encoding.TextUnmarshalers.
+	case reflect.PtrTo(keyType).Implements(textUnmarshalerType):
+		keyVal = reflect.New(keyType)
+		v := keyVal.Interface().(encoding.TextUnmarshaler)
+		err = v.UnmarshalText([]byte(key))
+		keyVal = keyVal.Elem()
+	// Otherwise, go to type specific behavior
+	default:
+		switch keyType.Kind() {
+		case reflect.String:
+			keyVal = reflect.ValueOf(key).Convert(keyType)
+		case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64:
+			n, parseErr := strconv.ParseInt(key, 10, 64)
+			if parseErr != nil || reflect.Zero(keyType).OverflowInt(n) {
+				err = fmt.Errorf("failed to unmarshal number key %v", key)
+			}
+			keyVal = reflect.ValueOf(n).Convert(keyType)
+		case reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64, reflect.Uintptr:
+			n, parseErr := strconv.ParseUint(key, 10, 64)
+			if parseErr != nil || reflect.Zero(keyType).OverflowUint(n) {
+				err = fmt.Errorf("failed to unmarshal number key %v", key)
+				break
+			}
+			keyVal = reflect.ValueOf(n).Convert(keyType)
+		case reflect.Float32, reflect.Float64:
+			if mc.EncodeKeysWithStringer {
+				parsed, err := strconv.ParseFloat(key, 64)
+				if err != nil {
+					return keyVal, fmt.Errorf("Map key is defined to be a decimal type (%v) but got error %v", keyType.Kind(), err)
+				}
+				keyVal = reflect.ValueOf(parsed)
+				break
+			}
+			fallthrough
+		default:
+			return keyVal, fmt.Errorf("unsupported key type: %v", keyType)
+		}
+	}
+	return keyVal, err
+}