Eclipse

SWTBot is an open-source Java based UI/functional testing tool for testing SWT, Eclipse and GEF based applications. It provides APIs that are simple to read and write. The APIs also hide the complexities involved with SWT and Eclipse. SWTBot also provides its own set of assertions that are useful for SWT. You can also use your own assertion framework with SWTBot. SWTBot integrates with Eclipse PDE, Eclipse headless testing framework, Ant and Tycho, so it's easy to use in your IDE and Headless Builds (as part of a CI job for example). SWTBot can run on all platforms that SWT runs on. Very few other testing tools provide such a wide variety of platforms.