fix(gnovm): enhance constant evaluation for array and map types

gnovm/pkg/gnolang/type_check.go

@@ -257,8 +257,22 @@ Main:
 		}
 		panic(fmt.Sprintf("%s (variable of type %s) is not constant", currExpr.Name, t))
 	case *TypeAssertExpr:
+		ty := evalStaticTypeOf(store, last, currExpr)
+		_, okCallExpr := parentExpr.(*CallExpr)
+		_, okArray := ty.(*ArrayType)
+		if okCallExpr && okArray {
+			break Main
+		}
 		panic(fmt.Sprintf("%s (comma, ok expression of type %s) is not constant", currExpr.String(), currExpr.Type))
 	case *IndexExpr:
+		ty := evalStaticTypeOf(store, last, currExpr)
+		_, okCallExpr := parentExpr.(*CallExpr)
+		_, okArray := ty.(*ArrayType)
+		if okCallExpr && okArray {
+			// TODO: should add a test after the fix of https://github.com/gnolang/gno/issues/3409
+			break Main
+		}
+
 		panic(fmt.Sprintf("%s (variable of type %s) is not constant", currExpr.String(), currExpr.X))
 	case *CallExpr:
 		ift := evalStaticTypeOf(store, last, currExpr.Func)
@@ -334,14 +348,15 @@ Main:
 
 			tt := pv.GetBlock(store).Source.GetStaticTypeOf(store, currExpr.Sel)
 			panic(fmt.Sprintf("%s (variable of type %s) is not constant", currExpr.String(), tt))
-		case *PointerType, *DeclaredType, *StructType, *InterfaceType:
-			ty := evalStaticTypeOf(store, last, currExpr.X)
-			panic(fmt.Sprintf("%s (variable of type %s) is not constant", currExpr.String(), ty))
-		case *TypeType:
-			ty := evalStaticType(store, last, currExpr.X)
-			panic(fmt.Sprintf("%s (variable of type %s) is not constant", currExpr.String(), ty))
-		case *NativeType:
-			ty := evalStaticTypeOf(store, last, currExpr.X)
+		case *PointerType, *DeclaredType, *StructType, *InterfaceType, *TypeType, *NativeType:
+			ty := evalStaticTypeOf(store, last, currExpr)
+			_, okCallExpr := parentExpr.(*CallExpr)
+			_, okArray := ty.(*ArrayType)
+
+			// special case for len, cap
+			if okCallExpr && okArray {
+				break Main
+			}
 			panic(fmt.Sprintf("%s (variable of type %s) is not constant", currExpr.String(), ty))
 		default:
 			panic(fmt.Sprintf(
@@ -356,8 +371,6 @@ Main:
 		}
 	case *ConstExpr:
 	case *BasicLitExpr:
-	case *CompositeLitExpr:
-		assertValidConstValue(store, last, currExpr.Type, parentExpr)
 	default:
 		ift := evalStaticTypeOf(store, last, currExpr)
 		if _, ok := ift.(*TypeType); ok {

gnovm/tests/files/const32.gno

@@ -8,4 +8,4 @@ func main() {
 }
 
 // Error:
-// main/files/const32.gno:6:8: [](const-type string) (variable of type []string) is not constant
+// main/files/const32.gno:6:8: [](const-type string){} (variable of type []string) is not constant

gnovm/tests/files/const36.gno

@@ -10,4 +10,4 @@ func main() {
 }
 
 // Error:
-// main/files/const36.gno:9:8: s<VPBlock(1,0)>.x (variable of type main.s) is not constant
+// main/files/const36.gno:9:8: s<VPBlock(1,0)>.x (variable of type int) is not constant

gnovm/tests/files/const38.gno

@@ -8,4 +8,4 @@ func main() {
 }
 
 // Error:
-// main/files/const38.gno:7:8: v<VPBlock(1,0)>.Denom (variable of type std.Coin) is not constant
+// main/files/const38.gno:7:8: v<VPBlock(1,0)>.Denom (variable of type string) is not constant

gnovm/tests/files/const45_a.gno

@@ -0,0 +1,14 @@
+package main
+
+type MyStruct struct {
+	arr [2]int
+}
+
+const a = len(MyStruct{arr: [2]int{1, 2}}.arr)
+
+func main() {
+	println("ok")
+}
+
+// Output:
+// ok

gnovm/tests/files/const45_b.gno

@@ -0,0 +1,14 @@
+package main
+
+type MyStruct struct {
+	arr []int
+}
+
+const a = len(MyStruct{arr: []int{1, 2}}.arr)
+
+func main() {
+	println("ok")
+}
+
+// Error:
+// main/files/const45_b.gno:7:7: MyStruct<VPBlock(2,0)>{arr<VPField(0,0,arr)>: [](const-type int){(const (1 int)), (const (2 int))}}.arr (variable of type []int) is not constant

gnovm/tests/files/const46.gno

@@ -0,0 +1,10 @@
+package main
+
+const a = len(map[string][2]int{"arr": {1, 2}}["arr"])
+
+func main() {
+	println("ok")
+}
+
+// Output:
+// ok

gnovm/tests/files/const47.gno

@@ -0,0 +1,10 @@
+package main
+
+const a = len(map[string][2]interface{}{"arr": {1, 2}}["arr"])
+
+func main() {
+	println("ok")
+}
+
+// Output:
+// ok

gnovm/tests/files/const48.gno

@@ -0,0 +1,9 @@
+package main
+
+func main() {
+	const a = len(map[string][]int{"arr": {1, 2}})
+	println("ok", a)
+}
+
+// Error:
+// main/files/const48.gno:4:8: map[(const-type string)] [](const-type int){(const ("arr" string)): (const-type []int){(const (1 int)), (const (2 int))}} (variable of type map[string][]int) is not constant