When writing tests, it is possible to avoid duplication of code by using the SetUp and TearDown methods built into NUnit. The Unity Test Framework has extended these methods with extra functionality, which can yield commands and skip frames, in the same way as UnityTest.
The actions related to a test run in the following order:
BeforeTest
invokedBeforeTest
method invokedAfterTest
method invokedAfterTest
invokedThe list of actions is the same for both Test
and UnityTest
.
The UnitySetUp
and UnityTearDown
attributes are identical to the standard SetUp
and TearDown
attributes, with the exception that they allow for yielding instructions. The UnitySetUp
and UnityTearDown
attributes expect a return type of IEnumerator.
public class SetUpTearDownExample
{
[UnitySetUp]
public IEnumerator SetUp()
{
yield return new EnterPlayMode();
}
[Test]
public void MyTest()
{
Debug.Log("This runs inside playmode");
}
[UnitySetUp]
public IEnumerator TearDown()
{
yield return new ExitPlayMode();
}
}
OuterUnityTestAction
is a wrapper outside of the tests, which allows for any tests with this attribute to run code before and after the tests. This method allows for yielding commands in the same way as UnityTest
. The attribute must inherit the NUnit
attribute and implement IOuterUnityTestAction
.
using System.Collections;
using NUnit.Framework;
using NUnit.Framework.Interfaces;
using UnityEngine;
using UnityEngine.TestTools;
public class MyTestClass
{
[UnityTest, MyOuterActionAttribute]
public IEnumerator MyTestInsidePlaymode()
{
Assert.IsTrue(Application.isPlaying);
yield return null;
}
}
public class MyOuterActionAttribute : NUnitAttribute, IOuterUnityTestAction
{
public IEnumerator BeforeTest(ITest test)
{
yield return new EnterPlayMode();
}
public IEnumerator AfterTest(ITest test)
{
yield return new ExitPlayMode();
}
}
In Edit Mode tests it is possible to yield instructions that can result in a domain reload, such as entering or exiting Play Mode (see Custom yield instructions). When a domain reload happens, all non-Unity actions (such as OneTimeSetup
and Setup
) are rerun before the code, which initiated the domain reload, continues. Unity actions (such as UnitySetup
) are not rerun. If the Unity action is the code that initiated the domain reload, then the rest of the code in the UnitySetup
method runs after the domain reload.