GUI Testing

Graphical user interface (GUI) testing is the process of testing a product’s GUI to ensure it meets its specification. 

The difficulty in accomplishing this task is twofold: to deal with domain size and with sequences. In addition, the tester faces more difficulty when they have to do regression testing.

A GUI may have many operations that need to be tested. For example, a small program such as WordPad has 325 possible GUI operations. In a large program, the number of operations can easily be an order of magnitude larger.

The second problem is the sequencing problem. Some functionality of the system may only be accomplished with a sequence of GUI events. For example, to open a file a user may have to first click on the File menu, then select the Open operation, use a dialog box to specify the file name and focus the application on the newly opened window. Increasing the number of possible operations increases the sequencing problem exponentially. This can become a serious issue when the tester is creating test cases manually.

Regression testing becomes a problem with GUIs as well. A GUI may change significantly, even though the underlying application does not. A test designed to follow a certain path through the GUI may then fail since a button, menu item, or dialog may have changed location or appearance. These issues have driven the GUI testing problem domain towards automation. Many different techniques have been proposed to automatically generate test suites that are complete and that simulate user behavior.

GUI testing tools serve the purpose of automating the testing process of software with graphical user interfaces.

Name	Supported platforms (testing system)	Supported platforms (tested system)	Developer	License
Appium	Windows, Linux, Mac (Python, C#, Ruby, Java, Javascript, PHP, Robot Framework)	iOS, Android (both native App & browser hosted app)	JS Foundation	Apache
iMacros	Web (cross-browser)	Web	iOpus	Proprietary
Katalon Studio	Windows, Linux, OS X	Web (UI & API), Mobile apps	Katalon LLC	Proprietary
Robot Framework	Web (cross-browser)	Web	(Collaborative project)	Apache
Selenium	Web (cross-browser)	Web	(Collaborative project)	Apache
TestComplete	Windows	Windows, Android, iOS, Web	SmartBear Software	Proprietary
Unified Functional Testing (UFT) previously named HP QuickTest Professional (QTP)	Windows	Windows, Web, Mobile, Terminal Emulators, SAP, Siebel, Java, .NET, Flex, others...	Hewlett-Packard Enterprise	Proprietary