fix: #2402 make sure a given element isn’t undefined before accessing properties (#2403)

lib/util.js

@@ -1488,17 +1488,19 @@ exports.topMost = function (pile, accessors) {
     accessors = [accessors];
   }
   for (const member of pile) {
-    candidate = member[accessors[0]];
-    for (let i = 1; i < accessors.length; i++){
+    if (member) {
+      candidate = member[accessors[0]];
+      for (let i = 1; i < accessors.length; i++){
+        if (candidate) {
+          candidate = candidate[accessors[i]]
+        } else {
+          continue;
+        }
+      }
       if (candidate) {
-        candidate = candidate[accessors[i]]
-      } else {
-        continue;
+        break;
       }
     }
-    if (candidate) {
-      break;
-    }
   }
   return candidate;
-}
+};