Unit Tests
ezEngine has a strong focus on reliability. Consequently, testing is taken very seriously. Due to the way game engines work, typical test frameworks are not a good fit, which is why EZ has its own test framework.
Test Framework
The test framework can be built purely for console execution or to have a graphical user interface. If the CMake variable EZ_ENABLE_QT_SUPPORT is set, the test applications will show a GUI (unless skipped via command line).
Command Line Options
Run any test suite with the argument -help to get the full list of available options.
Test Structure
The test framework works with tests and subtests. A test takes care of the slow initialization, like setting up the engine, the subtests then check various functionality, without rerunning the same initialization procedures. Tests and subtests can be disabled to focus on a specific issue.
All tests are derived from ezTestBaseClass and global instances in code are automatically picked up and shown in the UI. For trivial tests, as used in the FoundationTest application there are additional helper macros EZ_CREATE_SIMPLE_TEST_GROUP and EZ_CREATE_SIMPLE_TEST to add a new test with just two lines of code.
While running use the macros EZ_TEST_INT/FLOAT/STRING/... to check an assumption and make the test fail if it doesn't hold. There is also EZ_TEST_IMAGE and EZ_SCHEDULE_IMAGE_TEST to compare a screen capture against a stored reference image. You create reference images by running a succesful test once and then copying the result images to the proper folder. This can be done automatically for you through the Test Data menu in the GUI.
Writing tests is generally quite easy. All the test infrastructure is well documented. The best way to figure out how to write a test, is to run the different test suites to see which test is similar to what you want to do. Then look at that test, and jump to the C++ code comments of the test infrastructure to learn what it is for.
Test Suites
The tests can be included or excluded from the build using the CMake variable EZ_BUILD_UNITTESTS. If enabled, they show up in MSVC under the top level UnitTests folder.
The following test suites are available:
FoundationTest: These tests are for the absolute base functionality, that's found in the Foundation project and the Texture project.
CoreTest: These tests are for the core engine functionality, like the scenegraph and resource management.
RendererTest: This tests the basic rendering functionality that's available with the rendering API abstraction. It doesn't test the high level rendering features.
ToolsFoundationTest: This is for testing editor and tools specific infrastructure.
GameEngineTest: These tests use the full engine functionality to test various high level features. Therefore they cover various rendering features as well as game features.
EditorTest: This test runs the editor and exercises things like creating all types of asset documents, and so on.
RemoteTestHarness: This is a helper project to run tests on UWP.