diff --git a/test/built-ins/RegExp/prototype/Symbol.matchAll/isregexp-called-once.js b/test/built-ins/RegExp/prototype/Symbol.matchAll/isregexp-called-once.js
index 7281af422f55ecccb215cdfebae7e7a7795fac69..c3b3e173b359cba8b277e5634a074640b00d35e1 100644
--- a/test/built-ins/RegExp/prototype/Symbol.matchAll/isregexp-called-once.js
+++ b/test/built-ins/RegExp/prototype/Symbol.matchAll/isregexp-called-once.js
@@ -25,16 +25,32 @@ Object.defineProperty(RegExp.prototype, Symbol.match, {
   }
 });
 
-var count = 0;
+var calls = [];
 var o = {
   get [Symbol.match]() {
-    ++count;
+    calls.push('get @@match');
     return false;
   },
-  flags: "",
+  get flags() {
+    calls.push('get flags');
+    return {
+      toString() {
+        calls.push('flags toString');
+      }
+    };
+  },
 };
 
-RegExp.prototype[Symbol.matchAll].call(o, '1');
+RegExp.prototype[Symbol.matchAll].call(o, {
+  toString() {
+    calls.push('arg toString')
+  }
+});
 
 assert.sameValue(0, internalCount);
-assert.sameValue(1, count);
+
+assert.sameValue(calls.length, 4);
+assert.sameValue(calls[0], 'get @@match');
+assert.sameValue(calls[1], 'arg toString');
+assert.sameValue(calls[2], 'get flags');
+assert.sameValue(calls[3], 'flags toString');