repl: simplify code

This simplifies some repl code and removes a code branch that is
unreachable.

PR-URL: #30907
Reviewed-By: Michaël Zasso <targos@protonmail.com>
Reviewed-By: Rich Trott <rtrott@gmail.com>

lib/repl.js

@@ -953,7 +953,7 @@ REPLServer.prototype.createContext = function() {
   }
 
   const module = new CJSModule('<repl>');
-  module.paths = CJSModule._resolveLookupPaths('<repl>', parentModule) || [];
+  module.paths = CJSModule._resolveLookupPaths('<repl>', parentModule);
 
   ObjectDefineProperty(context, 'module', {
     configurable: true,
@@ -1307,21 +1307,17 @@ function complete(line, callback) {
             }
             // Works for non-objects
             try {
-              let sentinel = 5;
               let p;
               if (typeof obj === 'object' || typeof obj === 'function') {
                 p = ObjectGetPrototypeOf(obj);
               } else {
                 p = obj.constructor ? obj.constructor.prototype : null;
               }
-              while (p !== null) {
+              // Circular refs possible? Let's guard against that.
+              let sentinel = 5;
+              while (p !== null && sentinel-- !== 0) {
                 memberGroups.push(filteredOwnPropertyNames(p));
                 p = ObjectGetPrototypeOf(p);
-                // Circular refs possible? Let's guard against that.
-                sentinel--;
-                if (sentinel <= 0) {
-                  break;
-                }
               }
             } catch {}
           }