fix: handling values in map of interfaces

_test/map24.go

@@ -0,0 +1,18 @@
+package main
+
+import (
+	"encoding/json"
+	"fmt"
+)
+
+func main() {
+	jb := []byte(`{"property": "test"}`)
+	params := map[string]interface{}{"foo": 1}
+	if err := json.Unmarshal(jb, &params); err != nil {
+		panic("marshal failed.")
+	}
+	fmt.Println(params["foo"], params["property"])
+}
+
+// Output:
+// 1 test

_test/map25.go

@@ -0,0 +1,26 @@
+package main
+
+import (
+	"encoding/json"
+	"strconv"
+)
+
+func main() {
+	jb := []byte(`{"num": "2"}`)
+	params := map[string]interface{}{"foo": "1"}
+	if err := json.Unmarshal(jb, &params); err != nil {
+		panic(err)
+	}
+	sum := 0
+	for _, v := range params {
+		i, err := strconv.Atoi(v.(string))
+		if err != nil {
+			panic(err)
+		}
+		sum += i
+	}
+	println(sum)
+}
+
+// Output:
+// 3

interp/cfg.go

@@ -659,7 +659,7 @@ func (interp *Interpreter) cfg(root *node, pkgID string) ([]*node, error) {
 			wireChild(n)
 			t := n.child[0].typ
 			switch t.cat {
-			case ptrT:
+			case aliasT, ptrT:
 				n.typ = t.val
 				if t.val.cat == valueT {
 					n.typ = &itype{cat: valueT, rtype: t.val.rtype.Elem()}

interp/run.go

@@ -1032,6 +1032,9 @@ func getIndexArray(n *node) {
 	}
 }
 
+// valueInterfaceType is the reflection type of valueInterface
+var valueInterfaceType = reflect.TypeOf((*valueInterface)(nil)).Elem()
+
 // getIndexMap retrieves map value from index
 func getIndexMap(n *node) {
 	dest := genValue(n)
@@ -1057,7 +1060,11 @@ func getIndexMap(n *node) {
 			z = reflect.New(n.child[0].typ.val.frameType()).Elem()
 			n.exec = func(f *frame) bltn {
 				if v := value0(f).MapIndex(mi); v.IsValid() {
-					dest(f).Set(v.Elem())
+					if e := v.Elem(); e.Type().AssignableTo(valueInterfaceType) {
+						dest(f).Set(e)
+					} else {
+						dest(f).Set(reflect.ValueOf(valueInterface{n, e}))
+					}
 				} else {
 					dest(f).Set(z)
 				}
@@ -1091,7 +1098,11 @@ func getIndexMap(n *node) {
 			z = reflect.New(n.child[0].typ.val.frameType()).Elem()
 			n.exec = func(f *frame) bltn {
 				if v := value0(f).MapIndex(value1(f)); v.IsValid() {
-					dest(f).Set(v.Elem())
+					if e := v.Elem(); e.Type().AssignableTo(valueInterfaceType) {
+						dest(f).Set(e)
+					} else {
+						dest(f).Set(reflect.ValueOf(valueInterface{n, e}))
+					}
 				} else {
 					dest(f).Set(z)
 				}
@@ -1137,7 +1148,11 @@ func getIndexMap2(n *node) {
 			n.exec = func(f *frame) bltn {
 				v := value0(f).MapIndex(mi)
 				if v.IsValid() {
-					dest(f).Set(v.Elem())
+					if e := v.Elem(); e.Type().AssignableTo(valueInterfaceType) {
+						dest(f).Set(e)
+					} else {
+						dest(f).Set(reflect.ValueOf(valueInterface{n, e}))
+					}
 				}
 				if doStatus {
 					value2(f).SetBool(v.IsValid())
@@ -1169,7 +1184,11 @@ func getIndexMap2(n *node) {
 			n.exec = func(f *frame) bltn {
 				v := value0(f).MapIndex(value1(f))
 				if v.IsValid() {
-					dest(f).Set(v.Elem())
+					if e := v.Elem(); e.Type().AssignableTo(valueInterfaceType) {
+						dest(f).Set(e)
+					} else {
+						dest(f).Set(reflect.ValueOf(valueInterface{n, e}))
+					}
 				}
 				if doStatus {
 					value2(f).SetBool(v.IsValid())
@@ -1900,7 +1919,11 @@ func rangeMap(n *node) {
 					return fnext
 				}
 				f.data[index0].Set(iter.Key())
-				f.data[index1].Set(iter.Value().Elem())
+				if e := iter.Value().Elem(); e.Type().AssignableTo(valueInterfaceType) {
+					f.data[index1].Set(e)
+				} else {
+					f.data[index1].Set(reflect.ValueOf(valueInterface{n, e}))
+				}
 				return tnext
 			}
 		} else {

interp/value.go

@@ -79,7 +79,7 @@ func genValue(n *node) func(*frame) reflect.Value {
 	case basicLit:
 		v := n.rval
 		if !v.IsValid() {
-			v = reflect.New(reflect.TypeOf((*interface{})(nil)).Elem()).Elem()
+			v = reflect.New(interf).Elem()
 		}
 		return func(f *frame) reflect.Value { return v }
 	case funcDecl:
@@ -149,10 +149,9 @@ func genValueRangeArray(n *node) func(*frame) reflect.Value {
 
 func genValueInterfacePtr(n *node) func(*frame) reflect.Value {
 	value := genValue(n)
-	it := reflect.TypeOf((*interface{})(nil)).Elem()
 
 	return func(f *frame) reflect.Value {
-		v := reflect.New(it).Elem()
+		v := reflect.New(interf).Elem()
 		v.Set(value(f))
 		return v.Addr()
 	}
@@ -179,7 +178,7 @@ func genValueInterface(n *node) func(*frame) reflect.Value {
 
 func zeroInterfaceValue() reflect.Value {
 	n := &node{kind: basicLit, typ: &itype{cat: nilT, untyped: true}}
-	v := reflect.New(reflect.TypeOf((*interface{})(nil)).Elem()).Elem()
+	v := reflect.New(interf).Elem()
 	return reflect.ValueOf(valueInterface{n, v})
 }