Improve function names in debugger call stacks (#3310)

* improve function names in debugger callstacks

* pr review cleanup

* simplify if condition

Author: brianpeiris

src/core/a-register-element.js

@@ -58,6 +58,14 @@ module.exports.registerElement = function (tagName, obj) {
     newObj = {prototype: Object.create(proto, newObj)};
   }
 
+  // Give all functions their proper name.
+  for (var propName of Object.getOwnPropertyNames(newObj.prototype)) {
+    var propVal = newObj.prototype[propName];
+    if (typeof propVal === 'function') {
+      propVal.displayName = propName;
+    }
+  }
+
   return document.registerElement(tagName, newObj);
 };
 

tests/core/a-register-element.test.js

@@ -65,6 +65,20 @@ suite('a-register-element', function () {
       });
       document.body.appendChild(document.createElement('a-test-entity-2'));
     });
+
+    test('names functions correctly', function (done) {
+      registerElement('a-test-entity-3', {
+        prototype: Object.create(AEntity.prototype, {
+          attachedCallback: {
+            value: function () {
+              assert.equal(this.attachedCallback.displayName, 'attachedCallback');
+              done();
+            }
+          }
+        })
+      });
+      document.body.appendChild(document.createElement('a-test-entity-3'));
+    });
   });
 
   suite('wrapMethods', function () {