fix(gnovm): fix max names in block check

gnovm/pkg/gnolang/nodes.go

@@ -4,6 +4,7 @@ import (
 	"fmt"
 	"go/parser"
 	"go/token"
+	"math"
 	"os"
 	"path/filepath"
 	"reflect"
@@ -1802,7 +1803,7 @@ func (sb *StaticBlock) Define2(isConst bool, n Name, st Type, tv TypedValue) {
 	if int(sb.NumNames) != len(sb.Names) {
 		panic("StaticBlock.NumNames and len(.Names) mismatch")
 	}
-	if (1<<16 - 1) < sb.NumNames {
+	if sb.NumNames == math.MaxUint16 {
 		panic("too many variables in block")
 	}
 	if tv.T == nil && tv.V != nil {

gnovm/pkg/gnolang/nodes_test.go

@@ -0,0 +1,44 @@
+package gnolang_test
+
+import (
+	"math"
+	"testing"
+
+	"github.com/gnolang/gno/gnovm/pkg/gnolang"
+)
+
+func TestStaticBlock_Define2_MaxNames(t *testing.T) {
+	defer func() {
+		if r := recover(); r != nil {
+			panicString, ok := r.(string)
+			if !ok {
+				t.Errorf("expected panic string, got %v", r)
+			}
+
+			if panicString != "too many variables in block" {
+				t.Errorf("expected panic string to be 'too many variables in block', got '%s'", panicString)
+			}
+
+			return
+		}
+
+		// If it didn't panic, fail.
+		t.Errorf("expected panic when exceeding maximum number of names")
+	}()
+
+	staticBlock := new(gnolang.StaticBlock)
+	staticBlock.NumNames = math.MaxUint16 - 1
+	staticBlock.Names = make([]gnolang.Name, staticBlock.NumNames)
+
+	// Adding one more is okay.
+	staticBlock.Define2(false, gnolang.Name("a"), gnolang.BoolType, gnolang.TypedValue{T: gnolang.BoolType})
+	if staticBlock.NumNames != math.MaxUint16 {
+		t.Errorf("expected NumNames to be %d, got %d", math.MaxUint16, staticBlock.NumNames)
+	}
+	if len(staticBlock.Names) != math.MaxUint16 {
+		t.Errorf("expected len(Names) to be %d, got %d", math.MaxUint16, len(staticBlock.Names))
+	}
+
+	// This one should panic because the maximum number of names has been reached.
+	staticBlock.Define2(false, gnolang.Name("a"), gnolang.BoolType, gnolang.TypedValue{T: gnolang.BoolType})
+}