11. Scene-based tests

Learning objectives

In this exercise, you will learn how to test content that is stored in a scene.

Intro and motivation

A useful scenario for our customers is using the test framework for verifying the content of a scene. That could be checking for certain GameObjects and MonoBehaviors.

The EditorSceneManager allows for loading and saving scenes. In combination with the test framework, this allows for the implementation of tests that verify a scene.

When changing the state of the Editor in a test, such as loading a scene, it's good practice to clean up afterward. This can be done in a method with the [TearDown] attribute.

Exercise

Import the sample 11_SceneBasedTests, which contains a scene named MyGameScene and an assembly for Edit Mode tests.

The task is to create a test that opens the scene, verifies that the scene contains a game object named GameObjectToTestFor.

As cleanup, it should open a new empty scene, which is the default for Edit Mode tests. It is recommended to put that in a [TearDown], which ensures that the cleanup code is run, even if the test fails.

Hints

EditorSceneManager.OpenScene("Assets\\MyGameScene.unity"); loads the scene
EditorSceneManager.NewScene(NewSceneSetup.DefaultGameObjects, NewSceneMode.Single); cleans up by changing back to an empty scene.

Solution

A full solution is available in the sample 11_SceneBasedTests_Solution.

The test implementation can look like this:

public class SceneTests
{
 [SetUp]
 public void Setup()
 {
  EditorSceneManager.OpenScene("Assets\\MyGameScene.unity");
 }
 
 [Test]
 public void VerifyScene()
 {
  var gameObject = GameObject.Find("GameObjectToTestFor");
  
  Assert.That(gameObject, Is.Not.Null);
 }

 [TearDown]
 public void Teardown()
 {
  EditorSceneManager.NewScene(NewSceneSetup.DefaultGameObjects, NewSceneMode.Single);
 }
}