interp: fix map range handling

.travis.yml

@@ -19,7 +19,6 @@ cache:
 matrix:
   fast_finish: true
   include:
-    - go: 1.11.x
     - go: 1.12.x
     - go: 1.13.x
       env: STABLE=true

_test/range3.go

@@ -0,0 +1,14 @@
+package main
+
+import "fmt"
+
+func main() {
+	m := map[int]bool{1: true, 3: true, 5: true}
+	for k := range m {
+		m[k*2] = true
+	}
+	fmt.Println("ok")
+}
+
+// Output:
+// ok

_test/range4.go

@@ -0,0 +1,15 @@
+package main
+
+import "fmt"
+
+func main() {
+	m := map[int]bool{1: true, 3: true, 5: true}
+	for _, v := range m {
+		fmt.Println(v)
+	}
+}
+
+// Output:
+// true
+// true
+// true

_test/range5.go

@@ -0,0 +1,15 @@
+package main
+
+import "fmt"
+
+func main() {
+	m := map[int]bool{1: true, 3: true, 5: true}
+	var n int
+	for range m {
+		n++
+	}
+	fmt.Println(n)
+}
+
+// Output:
+// 3

_test/range6.go

@@ -0,0 +1,18 @@
+package main
+
+import (
+	"fmt"
+	"math"
+)
+
+func main() {
+	m := map[float64]bool{math.NaN(): true, math.NaN(): true, math.NaN(): true}
+	for _, v := range m {
+		fmt.Println(v)
+	}
+}
+
+// Output:
+// true
+// true
+// true

interp/cfg.go

@@ -87,6 +87,8 @@ func (interp *Interpreter) cfg(root *node) ([]*node, error) {
 						}
 					case mapT:
 						n.anc.gen = rangeMap
+						ityp := &itype{cat: valueT, rtype: reflect.TypeOf((*reflect.MapIter)(nil))}
+						sc.add(ityp)
 						ktyp = o.typ.key
 						vtyp = o.typ.val
 					case ptrT:

interp/run.go

@@ -1601,31 +1601,40 @@ func rangeChan(n *node) {
 }
 
 func rangeMap(n *node) {
-	index0 := n.child[0].findex   // array index location in frame
-	index1 := n.child[1].findex   // array value location in frame
-	value := genValue(n.child[2]) // array
+	index0 := n.child[0].findex // map index location in frame
+	index2 := index0 - 1        // iterator for range, always just behind index0
 	fnext := getExec(n.fnext)
 	tnext := getExec(n.tnext)
-	// TODO: move i and keys to frame
-	var i int
-	var keys []reflect.Value
 
+	var value func(*frame) reflect.Value
+	if len(n.child) == 4 {
+		index1 := n.child[1].findex  // map value location in frame
+		value = genValue(n.child[2]) // map
 		n.exec = func(f *frame) bltn {
-		a := value(f)
-		i++
-		if i >= a.Len() {
+			iter := f.data[index2].Interface().(*reflect.MapIter)
+			if !iter.Next() {
 				return fnext
 			}
-		f.data[index0].Set(keys[i])
-		f.data[index1].Set(a.MapIndex(keys[i]))
+			f.data[index0].Set(iter.Key())
+			f.data[index1].Set(iter.Value())
 			return tnext
 		}
+	} else {
+		value = genValue(n.child[1]) // map
+		n.exec = func(f *frame) bltn {
+			iter := f.data[index2].Interface().(*reflect.MapIter)
+			if !iter.Next() {
+				return fnext
+			}
+			f.data[index0].Set(iter.Key())
+			return tnext
+		}
+	}
 
 	// Init sequence
 	next := n.exec
 	n.child[0].exec = func(f *frame) bltn {
-		keys = value(f).MapKeys()
-		i = -1
+		f.data[index2].Set(reflect.ValueOf(value(f).MapRange()))
 		return next
 	}
 }