52 lines
1.9 KiB
Markdown
52 lines
1.9 KiB
Markdown
# 9\. Using the UnityTest Attribute
|
||
|
||
## Learning objectives
|
||
|
||
This section will introduce you to the custom `[UnityTest]` Attribute, which allows for creating tests that run over multiple frames.
|
||
|
||
## Intro and motivation
|
||
|
||
An important extension to the Nunit framework that we've made is introducing the `[UnityTest]` attribute. The attribute allows for creating tests that can yield and resume running after a certain condition. Therefore the test must have the return type of `IEnumerator`. You can then yield back a yield instruction or null, like so:
|
||
|
||
```
|
||
[UnityTest]
|
||
public IEnumerator MyTest()
|
||
{
|
||
DoSomething();
|
||
// Skip 1 frame.
|
||
yield return null;
|
||
DoSomethingElse();
|
||
}
|
||
```
|
||
|
||
In the snippet above we call the `DoSomething` method, then skip one frame before calling the `DoSomethingElse` method.
|
||
|
||
For more information on the yield keyword in C#, see the [Microsoft documentation](https://docs.microsoft.com/en-us/dotnet/csharp/language-reference/keywords/yield).
|
||
|
||
## Exercise
|
||
|
||
In the [sample](./welcome.md#import-samples) `9_UnityTestAttribute` you will find a Play Mode test assembly set up with one Play Mode test in it. The PlayMode test does not have a body yet, but there is a function called `PrepareCube()` which will set up a cube with some physics applied.
|
||
|
||
The task is to initialize the cube and then verify that it has moved after one frame has passed.
|
||
|
||
## Solution
|
||
|
||
The full solution is available in the `9_UnityTestAttribute_Solution` sample.
|
||
|
||
```
|
||
[UnityTest]
|
||
public IEnumerator CubeMovesDown()
|
||
{
|
||
var cubeUnderTest = PrepareCube();
|
||
var initialPosition = cubeUnderTest.transform.position;
|
||
|
||
yield return null;
|
||
|
||
Assert.That(cubeUnderTest.transform.position, Is.Not.EqualTo(initialPosition));
|
||
}
|
||
```
|
||
|
||
## Further reading and resources
|
||
|
||
[UTF documentation regarding UnityTest attribute](https://docs.unity3d.com/Packages/com.unity.test-framework@1.1/manual/reference-attribute-unitytest.html)
|