Actions outside of tests

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.

Action execution order

The actions related to a test run in the following order:

• Attributes implementing IApplyToContext
• Any attribute implementing OuterUnityTestAction has its BeforeTest invoked
• Tests with UnitySetUp methods in their test class.
• Attributes implementing IWrapSetUpTearDown
• Any SetUp attributes
• Action attributes have their BeforeTest method invoked
• Attributes implementing of IWrapTestMethod
  
• The test itself runs
• Action attributes have their AfterTest method invoked
• Any method with the TearDown attribute
• Tests with UnityTearDown methods in their test class
• Any OuterUnityTestAction has its AfterTest invoked

The list of actions is the same for both Test and UnityTest.

UnitySetUp and UnityTearDown

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.

Example

public class SetUpTearDownExample
{
    [UnitySetUp]
    public IEnumerator SetUp()
    {
        yield return new EnterPlayMode();
    }

    [Test]
    public void MyTest()
    {
        Debug.Log("This runs inside playmode");
    }

    [UnityTearDown]
    public IEnumerator TearDown()
    {

        yield return new ExitPlayMode();
    }
}

OuterUnityTestAction

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.

Example

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();
    }
}

Domain Reloads

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.