TestScene

Tsvrc.UdonTestKit.TestScene is a scene for Play Mode tests to run in: a new empty scene, or a scene asset such as your world's own. Loading it makes it the active scene, so ClientSim and the objects a test creates go into it, and unloading it destroys them.

ClientSimTestBase loads and unloads one for you when you pass it to the base constructor, as in Run tests in a scene of their own. You can also use it on its own.

Creating one

• TestScene.Empty(string name) is a new empty scene with that name. It's created each time it's loaded, so every load starts empty.
• TestScene.FromAsset(string assetPath) is the scene asset at that path, such as "Assets/Scenes/MyWorld.unity". It doesn't need to be in the build settings.

Neither one loads anything until Load runs.

Members

Load() is a coroutine: yield return scene.Load(). It loads the scene alongside the scenes already loaded, so the Unity Test Framework test scene stays loaded, and makes it the active scene. It does nothing when the scene is already loaded.

Unload() makes the scene that was active before Load active again, then unloads this scene and everything in it. It finishes before it returns, so it also works where a test can't wait, such as in [OneTimeTearDown]. It does nothing when the scene isn't loaded.

IsLoaded is true between a Load that finished and the next Unload.

Using it without the base class

Load it in a [UnitySetUp] and unload it once ClientSim has ended, such as in a [UnityTearDown]:

private readonly TestScene _scene = TestScene.Empty("Inventory");
private readonly ClientSimSession _session = new ClientSimSession();

[UnitySetUp]
public IEnumerator SetUp()
{
    yield return _scene.Load();
}

[UnityTearDown]
public IEnumerator TearDown()
{
    _session.End();
    _scene.Unload();
    yield break;
}

End the session before unloading the scene, the same order ClientSimTestBase uses.

Edge cases

• TestScene works only in Play Mode tests. FromAsset loads through EditorSceneManager.LoadSceneInPlayMode, which is why the scene doesn't need to be in the build settings.
• Unity drops the operation LoadSceneInPlayMode loads with. When the garbage collector finalized it as Unity exited, Unity crashed after every test had passed, so Load finalizes it right after the scene loads, while that's still safe.
• Unload uses the synchronous Unity SceneManager.UnloadScene, which Unity marks obsolete because it's unsafe inside physics callbacks. A test's setup and teardown aren't physics callbacks.

TestSceneLifetime

Tsvrc.UdonTestKit.TestSceneLifetime tells ClientSimTestBase how long its scene lives:

• PerTest, the default, loads a fresh copy for every test and unloads it after. Each test starts from the same scene, and whatever a test created is gone before the next one.
• PerFixture loads it for the first test in the class and unloads it after the last. The tests share whatever the earlier ones changed in it.