feat: use exported methods when setting go values (#469)

When putting JavaScript objects into _go*object use exported values.
This reverts PR #467 in favour of this more complete work.

Fixes #118 #252

Co-authored-by: Dmitry Panov <dop@itoolabs.com>

reflect_test.go

@@ -8,6 +8,8 @@ import (
 	"reflect"
 	"strings"
 	"testing"
+
+	"github.com/stretchr/testify/require"
 )
 
 type _abcStruct struct {
@@ -138,14 +140,16 @@ func (mno _mnoStruct) Func() string {
 }
 
 func TestReflect(t *testing.T) {
-	if true {
-		return
-	}
 	tt(t, func() {
 		// Testing dbgf
 		// These should panic
-		toValue("Xyzzy").toReflectValue(reflect.Ptr)
-		stringToReflectValue("Xyzzy", reflect.Ptr)
+		str := "test"
+		require.Panics(t, func() {
+			toValue("Xyzzy").toReflectValue(reflect.ValueOf(&str).Type())
+		})
+		require.Panics(t, func() {
+			stringToReflectValue("Xyzzy", reflect.Ptr)
+		})
 	})
 }
 
@@ -708,7 +712,7 @@ func Test_reflectMapInterface(t *testing.T) {
             `, "Nothing happens.,1,[object Object],[object Object]")
 
 			is(abc["xyz"], "pqr")
-			is(abc["ghi"], "[object Object]")
+			is(abc["ghi"], map[string]interface{}{})
 			is(abc["jkl"], float64(3.14159))
 			mno, valid := abc["mno"].(*_abcStruct)
 			is(valid, true)

type_go_array.go

@@ -62,7 +62,7 @@ func (self _goArrayObject) setValue(index int64, value Value) bool {
 	if !exists {
 		return false
 	}
-	reflectValue, err := value.toReflectValue(reflect.Indirect(self.value).Type().Elem().Kind())
+	reflectValue, err := value.toReflectValue(reflect.Indirect(self.value).Type().Elem())
 	if err != nil {
 		panic(err)
 	}

type_go_map.go

@@ -14,8 +14,8 @@ func (runtime *_runtime) newGoMapObject(value reflect.Value) *_object {
 
 type _goMapObject struct {
 	value     reflect.Value
-	keyKind   reflect.Kind
-	valueKind reflect.Kind
+	keyType   reflect.Type
+	valueType reflect.Type
 }
 
 func _newGoMapObject(value reflect.Value) *_goMapObject {
@@ -24,22 +24,22 @@ func _newGoMapObject(value reflect.Value) *_goMapObject {
 	}
 	self := &_goMapObject{
 		value:     value,
-		keyKind:   value.Type().Key().Kind(),
-		valueKind: value.Type().Elem().Kind(),
+		keyType:   value.Type().Key(),
+		valueType: value.Type().Elem(),
 	}
 	return self
 }
 
 func (self _goMapObject) toKey(name string) reflect.Value {
-	reflectValue, err := stringToReflectValue(name, self.keyKind)
+	reflectValue, err := stringToReflectValue(name, self.keyType.Kind())
 	if err != nil {
 		panic(err)
 	}
 	return reflectValue
 }
 
 func (self _goMapObject) toValue(value Value) reflect.Value {
-	reflectValue, err := value.toReflectValue(self.valueKind)
+	reflectValue, err := value.toReflectValue(self.valueType)
 	if err != nil {
 		panic(err)
 	}

type_go_slice.go

@@ -53,7 +53,7 @@ func (self *_goSliceObject) setLength(value Value) {
 }
 
 func (self *_goSliceObject) setValue(index int64, value Value) bool {
-	reflectValue, err := value.toReflectValue(self.value.Type().Elem().Kind())
+	reflectValue, err := value.toReflectValue(self.value.Type().Elem())
 	if err != nil {
 		panic(err)
 	}

value.go

@@ -645,13 +645,6 @@ func (self Value) export() interface{} {
 		case *_goStructObject:
 			return value.value.Interface()
 		case *_goMapObject:
-			iter := value.value.MapRange()
-			for iter.Next() {
-				v := iter.Value()
-				if ov, ok := v.Interface().(Value); ok {
-					value.value.SetMapIndex(iter.Key(), reflect.ValueOf(ov.export()))
-				}
-			}
 			return value.value.Interface()
 		case *_goArrayObject:
 			return value.value.Interface()
@@ -756,42 +749,13 @@ func (self Value) evaluateBreak(labels []string) _resultKind {
 	return resultReturn
 }
 
-func (self Value) exportNative() interface{} {
-	switch self.kind {
-	case valueUndefined:
-		return self
-	case valueNull:
-		return nil
-	case valueNumber, valueBoolean:
-		return self.value
-	case valueString:
-		switch value := self.value.(type) {
-		case string:
-			return value
-		case []uint16:
-			return string(utf16.Decode(value))
-		}
-	case valueObject:
-		object := self._object()
-		switch value := object.value.(type) {
-		case *_goStructObject:
-			return value.value.Interface()
-		case *_goMapObject:
-			return value.value.Interface()
-		case *_goArrayObject:
-			return value.value.Interface()
-		case *_goSliceObject:
-			return value.value.Interface()
-		}
-	}
-
-	return self
-}
-
 // Make a best effort to return a reflect.Value corresponding to reflect.Kind, but
 // fallback to just returning the Go value we have handy.
-func (value Value) toReflectValue(kind reflect.Kind) (reflect.Value, error) {
-	if kind != reflect.Float32 && kind != reflect.Float64 && kind != reflect.Interface {
+func (value Value) toReflectValue(typ reflect.Type) (reflect.Value, error) {
+	kind := typ.Kind()
+	switch kind {
+	case reflect.Float32, reflect.Float64, reflect.Interface:
+	default:
 		switch value := value.value.(type) {
 		case float32:
 			_, frac := math.Modf(float64(value))
@@ -808,36 +772,36 @@ func (value Value) toReflectValue(kind reflect.Kind) (reflect.Value, error) {
 
 	switch kind {
 	case reflect.Bool: // Bool
-		return reflect.ValueOf(value.bool()), nil
+		return reflect.ValueOf(value.bool()).Convert(typ), nil
 	case reflect.Int: // Int
 		// We convert to float64 here because converting to int64 will not tell us
 		// if a value is outside the range of int64
 		tmp := toIntegerFloat(value)
 		if tmp < float_minInt || tmp > float_maxInt {
 			return reflect.Value{}, fmt.Errorf("RangeError: %f (%v) to int", tmp, value)
 		} else {
-			return reflect.ValueOf(int(tmp)), nil
+			return reflect.ValueOf(int(tmp)).Convert(typ), nil
 		}
 	case reflect.Int8: // Int8
 		tmp := value.number().int64
 		if tmp < int64_minInt8 || tmp > int64_maxInt8 {
 			return reflect.Value{}, fmt.Errorf("RangeError: %d (%v) to int8", tmp, value)
 		} else {
-			return reflect.ValueOf(int8(tmp)), nil
+			return reflect.ValueOf(int8(tmp)).Convert(typ), nil
 		}
 	case reflect.Int16: // Int16
 		tmp := value.number().int64
 		if tmp < int64_minInt16 || tmp > int64_maxInt16 {
 			return reflect.Value{}, fmt.Errorf("RangeError: %d (%v) to int16", tmp, value)
 		} else {
-			return reflect.ValueOf(int16(tmp)), nil
+			return reflect.ValueOf(int16(tmp)).Convert(typ), nil
 		}
 	case reflect.Int32: // Int32
 		tmp := value.number().int64
 		if tmp < int64_minInt32 || tmp > int64_maxInt32 {
 			return reflect.Value{}, fmt.Errorf("RangeError: %d (%v) to int32", tmp, value)
 		} else {
-			return reflect.ValueOf(int32(tmp)), nil
+			return reflect.ValueOf(int32(tmp)).Convert(typ), nil
 		}
 	case reflect.Int64: // Int64
 		// We convert to float64 here because converting to int64 will not tell us
@@ -846,7 +810,7 @@ func (value Value) toReflectValue(kind reflect.Kind) (reflect.Value, error) {
 		if tmp < float_minInt64 || tmp > float_maxInt64 {
 			return reflect.Value{}, fmt.Errorf("RangeError: %f (%v) to int", tmp, value)
 		} else {
-			return reflect.ValueOf(int64(tmp)), nil
+			return reflect.ValueOf(int64(tmp)).Convert(typ), nil
 		}
 	case reflect.Uint: // Uint
 		// We convert to float64 here because converting to int64 will not tell us
@@ -855,28 +819,28 @@ func (value Value) toReflectValue(kind reflect.Kind) (reflect.Value, error) {
 		if tmp < 0 || tmp > float_maxUint {
 			return reflect.Value{}, fmt.Errorf("RangeError: %f (%v) to uint", tmp, value)
 		} else {
-			return reflect.ValueOf(uint(tmp)), nil
+			return reflect.ValueOf(uint(tmp)).Convert(typ), nil
 		}
 	case reflect.Uint8: // Uint8
 		tmp := value.number().int64
 		if tmp < 0 || tmp > int64_maxUint8 {
 			return reflect.Value{}, fmt.Errorf("RangeError: %d (%v) to uint8", tmp, value)
 		} else {
-			return reflect.ValueOf(uint8(tmp)), nil
+			return reflect.ValueOf(uint8(tmp)).Convert(typ), nil
 		}
 	case reflect.Uint16: // Uint16
 		tmp := value.number().int64
 		if tmp < 0 || tmp > int64_maxUint16 {
 			return reflect.Value{}, fmt.Errorf("RangeError: %d (%v) to uint16", tmp, value)
 		} else {
-			return reflect.ValueOf(uint16(tmp)), nil
+			return reflect.ValueOf(uint16(tmp)).Convert(typ), nil
 		}
 	case reflect.Uint32: // Uint32
 		tmp := value.number().int64
 		if tmp < 0 || tmp > int64_maxUint32 {
 			return reflect.Value{}, fmt.Errorf("RangeError: %d (%v) to uint32", tmp, value)
 		} else {
-			return reflect.ValueOf(uint32(tmp)), nil
+			return reflect.ValueOf(uint32(tmp)).Convert(typ), nil
 		}
 	case reflect.Uint64: // Uint64
 		// We convert to float64 here because converting to int64 will not tell us
@@ -885,7 +849,7 @@ func (value Value) toReflectValue(kind reflect.Kind) (reflect.Value, error) {
 		if tmp < 0 || tmp > float_maxUint64 {
 			return reflect.Value{}, fmt.Errorf("RangeError: %f (%v) to uint64", tmp, value)
 		} else {
-			return reflect.ValueOf(uint64(tmp)), nil
+			return reflect.ValueOf(uint64(tmp)).Convert(typ), nil
 		}
 	case reflect.Float32: // Float32
 		tmp := value.float64()
@@ -896,13 +860,13 @@ func (value Value) toReflectValue(kind reflect.Kind) (reflect.Value, error) {
 		if tmp1 > 0 && (tmp1 < math.SmallestNonzeroFloat32 || tmp1 > math.MaxFloat32) {
 			return reflect.Value{}, fmt.Errorf("RangeError: %f (%v) to float32", tmp, value)
 		} else {
-			return reflect.ValueOf(float32(tmp)), nil
+			return reflect.ValueOf(float32(tmp)).Convert(typ), nil
 		}
 	case reflect.Float64: // Float64
 		value := value.float64()
-		return reflect.ValueOf(float64(value)), nil
+		return reflect.ValueOf(float64(value)).Convert(typ), nil
 	case reflect.String: // String
-		return reflect.ValueOf(value.string()), nil
+		return reflect.ValueOf(value.string()).Convert(typ), nil
 	case reflect.Invalid: // Invalid
 	case reflect.Complex64: // FIXME? Complex64
 	case reflect.Complex128: // FIXME? Complex128
@@ -924,7 +888,11 @@ func (value Value) toReflectValue(kind reflect.Kind) (reflect.Value, error) {
 			case *_goSliceObject: // Slice
 				return reflect.ValueOf(vl.value.Interface()), nil
 			}
-			return reflect.ValueOf(value.exportNative()), nil
+			exported := reflect.ValueOf(value.export())
+			if exported.Type().ConvertibleTo(typ) {
+				return exported.Convert(typ), nil
+			}
+			return reflect.Value{}, fmt.Errorf("TypeError: could not convert %v to reflect.Type: %v", exported, typ)
 		case valueEmpty, valueResult, valueReference:
 			// These are invalid, and should panic
 		default:
@@ -933,7 +901,7 @@ func (value Value) toReflectValue(kind reflect.Kind) (reflect.Value, error) {
 	}
 
 	// FIXME Should this end up as a TypeError?
-	panic(fmt.Errorf("invalid conversion of %v (%v) to reflect.Kind: %v", value.kind, value, kind))
+	panic(fmt.Errorf("invalid conversion of %v (%v) to reflect.Type: %v", value.kind, value, typ))
 }
 
 func stringToReflectValue(value string, kind reflect.Kind) (reflect.Value, error) {

value_test.go

@@ -307,7 +307,7 @@ func TestExport(t *testing.T) {
 func Test_toReflectValue(t *testing.T) {
 	tt(t, func() {
 		value := toValue(0.0)
-		tmp, err := value.toReflectValue(reflect.Float32)
+		tmp, err := value.toReflectValue(reflect.TypeOf(0.0))
 		is(tmp.Float(), 0.0)
 		is(err, nil)
 	})