pkg/proc: extend conversion about `string` for array/str

Extend `string()`
1.convert `byte/rune array`(not only `slice`) to string.
2.convert string to string(itself), just like `string(str)` in go language.

_fixtures/testvariables2.go

@@ -246,6 +246,9 @@ func main() {
 	byteslice := []byte{116, 195, 168, 115, 116}
 	runeslice := []rune{116, 232, 115, 116}
 
+	bytearray := [5]byte{116, 195, 168, 115, 116}
+	runearray := [4]rune{116, 232, 115, 116}
+
 	longstr := "very long string 0123456789a0123456789b0123456789c0123456789d0123456789e0123456789f0123456789g012345678h90123456789i0123456789j0123456789"
 
 	var nilstruct *astruct = nil
@@ -270,5 +273,5 @@ func main() {
 	}
 
 	runtime.Breakpoint()
-	fmt.Println(i1, i2, i3, p1, amb1, s1, s3, a1, p2, p3, s2, as1, str1, f1, fn1, fn2, nilslice, nilptr, ch1, chnil, m1, mnil, m2, m3, up1, i4, i5, i6, err1, err2, errnil, iface1, iface2, ifacenil, arr1, parr, cpx1, const1, iface3, iface4, recursive1, recursive1.x, iface5, iface2fn1, iface2fn2, bencharr, benchparr, mapinf, mainMenu, b, b2, sd, anonstruct1, anonstruct2, anoniface1, anonfunc, mapanonstruct1, ifacearr, efacearr, ni8, ni16, ni32, pinf, ninf, nan, zsvmap, zsslice, zsvar, tm, errtypednil, emptyslice, emptymap, byteslice, runeslice, longstr, nilstruct, as2, as2.NonPointerRecieverMethod, s4, iface2map)
+	fmt.Println(i1, i2, i3, p1, amb1, s1, s3, a1, p2, p3, s2, as1, str1, f1, fn1, fn2, nilslice, nilptr, ch1, chnil, m1, mnil, m2, m3, up1, i4, i5, i6, err1, err2, errnil, iface1, iface2, ifacenil, arr1, parr, cpx1, const1, iface3, iface4, recursive1, recursive1.x, iface5, iface2fn1, iface2fn2, bencharr, benchparr, mapinf, mainMenu, b, b2, sd, anonstruct1, anonstruct2, anoniface1, anonfunc, mapanonstruct1, ifacearr, efacearr, ni8, ni16, ni32, pinf, ninf, nan, zsvmap, zsslice, zsvar, tm, errtypednil, emptyslice, emptymap, byteslice, runeslice, bytearray, runearray, longstr, nilstruct, as2, as2.NonPointerRecieverMethod, s4, iface2map)
 }

pkg/proc/eval.go

@@ -114,15 +114,25 @@ func (scope *EvalScope) evalToplevelTypeCast(t ast.Expr, cfg LoadConfig) (*Varia
 
 	case "string":
 		switch argv.Kind {
+		case reflect.String:
+			s := constant.StringVal(argv.Value)
+			v.Value = constant.MakeString(s)
+			v.Len = int64(len(s))
+			return v, nil
 		case reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64, reflect.Int, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64, reflect.Uint, reflect.Uintptr:
 			b, _ := constant.Int64Val(argv.Value)
 			s := string(b)
 			v.Value = constant.MakeString(s)
 			v.Len = int64(len(s))
 			return v, nil
-
-		case reflect.Slice:
-			switch elemType := argv.RealType.(*godwarf.SliceType).ElemType.(type) {
+		case reflect.Slice, reflect.Array:
+			var elem godwarf.Type
+			if argv.Kind == reflect.Slice {
+				elem = argv.RealType.(*godwarf.SliceType).ElemType
+			} else {
+				elem = argv.RealType.(*godwarf.ArrayType).Type
+			}
+			switch elemType := elem.(type) {
 			case *godwarf.UintType:
 				if elemType.Name != "uint8" && elemType.Name != "byte" {
 					return nil, nil

service/test/variables_test.go

@@ -784,6 +784,9 @@ func TestEvalExpression(t *testing.T) {
 		{"string(runeslice)", false, `"tèst"`, `""`, "string", nil},
 		{"[]byte(string(runeslice))", false, `[]uint8 len: 5, cap: 5, [116,195,168,115,116]`, `[]uint8 len: 0, cap: 0, nil`, "[]uint8", nil},
 		{"*(*[5]byte)(uintptr(&byteslice[0]))", false, `[5]uint8 [116,195,168,115,116]`, `[5]uint8 [...]`, "[5]uint8", nil},
+		{"string(bytearray)", false, `"tèst"`, `""`, "string", nil},
+		{"string(runearray)", false, `"tèst"`, `""`, "string", nil},
+		{"string(str1)", false, `"01234567890"`, `"01234567890"`, "string", nil},
 
 		// access to channel field members
 		{"ch1.qcount", false, "4", "4", "uint", nil},