[Refactor] Test: a more precise check

Author: ljharb

lib/test.js

@@ -221,7 +221,7 @@ function wrapFunction(original) {
 			var args = $slice(arguments);
 			var completed = false;
 			try {
-				var returned = original ? bound(this, arguments) : void undefined;
+				var returned = bound ? bound(this, arguments) : void undefined;
 				$push(calls, { args: args, receiver: this, returned: returned });
 				completed = true;
 				return returned;