diff --git a/src/class-elements/private-methods/cls-decl.template b/src/class-elements/private-methods/cls-decl.template
index 677c338146afaf64ff6d928b1dd6826116700d4c..8ef950e3cd789ea5b87600f5c4baf70d8043954d 100644
--- a/src/class-elements/private-methods/cls-decl.template
+++ b/src/class-elements/private-methods/cls-decl.template
@@ -73,8 +73,12 @@ esid: prod-MethodDefinition
  * the template provides c.ref() for external reference
  */
 
-function hasOwnProperty(obj, name) {
-  return Object.prototype.hasOwnProperty.call(obj, name);
+function hasProp(obj, name, expected, msg) {
+  var hasOwnProperty = Object.prototype.hasOwnProperty.call(obj, name);
+  assert.sameValue(hasOwnProperty, expected, msg);
+
+  var hasProperty = Reflect.has(obj, name);
+  assert.sameValue(hasProperty, expected, msg);
 }
 
 class C {
@@ -83,12 +87,9 @@ class C {
   get ref() { return this.#m; }
 
   constructor() {
-    assert.sameValue(
-      hasOwnProperty(this, '#m'), false,
-      'private methods are defined in an special internal slot and cannot be found as own properties'
-    );
+    hasProp(this, '#m', false, 'private methods are defined in an special internal slot and cannot be found as own properties');
     assert.sameValue(typeof this.#m, 'function');
-    assert.sameValue(this.ref(), this.#m, 'returns the same value');
+    assert.sameValue(this.ref, this.#m, 'returns the same value');
 
     /*{ constructor }*/
   }
@@ -97,20 +98,9 @@ class C {
 var c = new C();
 var other = new C();
 
-assert.sameValue(
-  hasOwnProperty(C.prototype, '#m'), false,
-  'method is not defined in the prototype'
-);
-
-assert.sameValue(
-  hasOwnProperty(C, '#m'), false,
-  'method is not defined in the contructor'
-);
-
-assert.sameValue(
-  hasOwnProperty(c, '#m'), false,
-  'method cannot be seen outside of the class'
-);
+hasProp(C.prototype, '#m', false, 'method is not defined in the prototype');
+hasProp(C, '#m', false, 'method is not defined in the contructor');
+hasProp(c, '#m', false, 'method cannot be seen outside of the class');
 
 /***
  * MethodDefinition : ClassElementName ( UniqueFormalParameters ) { FunctionBody }
diff --git a/src/class-elements/private-methods/cls-expr.template b/src/class-elements/private-methods/cls-expr.template
index 781304d72c3df209e2e7be06749c50aed6c49fc2..dd301c9065820bfc176a65446319e426b599b493 100644
--- a/src/class-elements/private-methods/cls-expr.template
+++ b/src/class-elements/private-methods/cls-expr.template
@@ -4,6 +4,7 @@
 /*---
 path: language/expressions/class/private-methods/
 name: private method definitions in a class expression
+features: [class, class-methods-private]
 info: |
   ClassElement :
     MethodDefinition
@@ -73,8 +74,12 @@ esid: prod-MethodDefinition
  * 2. the template provides c.ref/other.ref for external reference
  */
 
-function hasOwnProperty(obj, name) {
-  return Object.prototype.hasOwnProperty.call(obj, name);
+function hasProp(obj, name, expected, msg) {
+  var hasOwnProperty = Object.prototype.hasOwnProperty.call(obj, name);
+  assert.sameValue(hasOwnProperty, expected, msg);
+
+  var hasProperty = Reflect.has(obj, name);
+  assert.sameValue(hasProperty, expected, msg);
 }
 
 var C = class {
@@ -83,12 +88,9 @@ var C = class {
   get ref() { return this.#m; }
 
   constructor() {
-    assert.sameValue(
-      hasOwnProperty(this, '#m'), false,
-      'private methods are defined in an special internal slot and cannot be found as own properties'
-    );
+    hasProp(this, '#m', false, 'private methods are defined in an special internal slot and cannot be found as own properties');
     assert.sameValue(typeof this.#m, 'function');
-    assert.sameValue(this.ref(), this.#m, 'returns the same value');
+    assert.sameValue(this.ref, this.#m, 'returns the same value');
 
     /*{ constructor }*/
   }
@@ -97,20 +99,9 @@ var C = class {
 var c = new C();
 var other = new C();
 
-assert.sameValue(
-  hasOwnProperty(C.prototype, '#m'), false,
-  'method is not defined in the prototype'
-);
-
-assert.sameValue(
-  hasOwnProperty(C, '#m'), false,
-  'method is not defined in the contructor'
-);
-
-assert.sameValue(
-  hasOwnProperty(c, '#m'), false,
-  'method cannot be seen outside of the class'
-);
+hasProp(C.prototype, '#m', false, 'method is not defined in the prototype');
+hasProp(C, '#m', false, 'method is not defined in the contructor');
+hasProp(c, '#m', false, 'method cannot be seen outside of the class');
 
 /***
  * MethodDefinition : ClassElementName ( UniqueFormalParameters ) { FunctionBody }
diff --git a/src/class-elements/prod-private-async-generator.case b/src/class-elements/prod-private-async-generator.case
index 6c3c0299a7fccb2652c60cd097666e24b5a70857..58490b79341cacab8040e9dd6f86e5acb8fb4988 100644
--- a/src/class-elements/prod-private-async-generator.case
+++ b/src/class-elements/prod-private-async-generator.case
@@ -26,6 +26,7 @@ assert.sameValue(this.#m.name, '#m', 'function name inside constructor');
 //- assertions
 assert.sameValue(c.ref.name, '#m', 'function name is preserved external reference');
 ctorPromise.then(() => {
+    // gets the returned async iterator from #m
     var iter = c.ref();
     return iter.next().then(({ value, done }) => {
         assert.sameValue(value, 42, 'return from generator method');
diff --git a/src/class-elements/prod-private-async-method.case b/src/class-elements/prod-private-async-method.case
index 173575866b301cffc7ac84bf9bb16e6857e82380..872c31c74b2ff34f07c861d550aa9d74c95b4de3 100644
--- a/src/class-elements/prod-private-async-method.case
+++ b/src/class-elements/prod-private-async-method.case
@@ -23,6 +23,7 @@ ctorPromise = this.#m().then(value => {
 //- assertions
 assert.sameValue(c.ref.name, '#m', 'function name is preserved external reference');
 ctorPromise.then(() => {
+    // gets the returned promise from #m
     return c.ref().then(value => {
         assert.sameValue(value, 42, 'function return');
     });
diff --git a/src/class-elements/prod-private-generator.case b/src/class-elements/prod-private-generator.case
index 5d5821a900cf0f874cd23657a621ae0a02bc710b..334ca1cb122b6bb79f44dda63e7776b55a2456e7 100644
--- a/src/class-elements/prod-private-generator.case
+++ b/src/class-elements/prod-private-generator.case
@@ -17,6 +17,7 @@ assert.sameValue(res.done, true, 'iterator is done, inside ctor');
 assert.sameValue(this.#m.name, '#m', 'function name inside constructor');
 
 //- assertions
+// gets the returned iterator from #m
 var res = c.ref().next();
 assert.sameValue(res.value, 42, 'return from generator method');
 assert.sameValue(res.done, true, 'iterator is done');
diff --git a/src/class-elements/prod-private-method.case b/src/class-elements/prod-private-method.case
index 4e82ae18b7271775c8d8809985c0eb4c15c64a39..38a916877960db7dc02f299400e3a1bcb30751ad 100644
--- a/src/class-elements/prod-private-method.case
+++ b/src/class-elements/prod-private-method.case
@@ -14,5 +14,6 @@ assert.sameValue(this.#m(), 42, 'already defined in the ctor');
 assert.sameValue(this.#m.name, '#m', 'function name inside constructor');
 
 //- assertions
+// gets the returned value from #m
 assert.sameValue(c.ref(), 42, 'function return');
 assert.sameValue(c.ref.name, '#m', 'function name is preserved external reference');