Using Flax native testing infrastructure in a game project

Scripting C++
1

Hi,

We are currently investigating the possibility of adding unit tests to the C++ code of our game project, and before adding an external testing setup, we noticed that Flax already has a native testing infrastructure based on Catch2.

From what we understand so far:

  • The engine tests are located in Source/Engine/Tests.
  • They use Catch2 (ThirdParty/catch2/catch.hpp).
  • FlaxTestsTarget, defined in Source/FlaxTests.Build.cs, builds the FlaxTests executable and adds the Tests module.
  • FlaxTestsTarget::SelectReferencedTarget() also looks specifically for a target named FlaxNativeTests in referenced projects, although we couldn’t find such a target defined anywhere in the FlaxEngine repository.

We built FlaxTestsTarget successfully and ran FlaxTests.exe. We also tried FlaxTests.exe -help, expecting perhaps some information about its usage, but that simply started the Flax tests.

So we wonder if this testing framework is intended to be usable by game projects, or if FlaxTestsTarget and FlaxNativeTests are mainly internal framework for testing Flax itself.

For example, let’s say we have a game module:

public class Game : GameModule
{
    // ...
}

and we want to write Catch2 tests for some of its native C++ code, is there an intended way to define a test module/target in the game project and run it using Flax’s existing testing infrastructure?

Or would you instead recommend implementing a separate testing solution for the game code?

We mainly try to understand the intended workflow before building something around what might be an internal implementation detail.

Thanks :slight_smile:

2

I think the easiest way is to make a module with tests code and reference it in Editor build of the game target. Then run those test on specific command line (`Engine::GetCommandLine()`, eg. as headless Command line access | Flax Documentation) or from editor UI.

Other way would be to make a new target script that references a tests module and builds a standalone executable, just like we do for FlaxTests. That’s a nice way but might require more steps.

Also, there is an old unit testing project: GitHub - FlaxCommunityProjects/FlaxUnitTesting: Simple flax engine unit testing · GitHub

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