Quickstart Unity C# test template. Not perfect, but gets you testing now.

FeatureTests.cs

using System.Collections;
using System.Threading.Tasks;
using NUnit.Framework;
using UnityEngine;
using UnityEngine.TestTools;

// Namespace should mirror the implementation namespace with a '.Tests' suffix.
// If the implementation is under 'MyCompany.FeatureScope', then tests should be 'MyCompany.Tests.FeatureScope'.
namespace MyCompany.Tests.FeatureScope
{
    // Class name should be the same as the implementation class with a 'Tests' suffix.
    // If you have a class named 'Feature', then the test class should be 'FeatureTests'.
    public class FeatureTests
    {
        private GameObject testObject;

        [SetUp]
        public void SetUp()
        {
            // Setup code for each test
            var go = new GameObject("TestObject");
            testObject = go;
        }

        [TearDown]
        public void TearDown()
        {
            // Cleanup after each test method
            Object.DestroyImmediate(testObject);
        }

        // Method names should mirror the corresponding method names in the implementation, 
        // optionally with an additional descriptor. For example, if testing a method 'Create' in the implementation,
        // a good test name might be 'Create_Succeeds'.
        [Test]
        public void CreateGameObject_EditMode()
        {
            Assert.AreEqual("TestObject", testObject.name);
        }

        [UnityTest]
        public IEnumerator CreateGameObject_PlayMode()
        {
            yield return null;
            Assert.AreEqual("TestObject", testObject.name);
        }

        // Example integration test
        [UnityTest]
        public IEnumerator ExampleIntegrationTest_Success()
        {
            yield return null;  // Wait one frame

            // Simulate some asynchronous action, like making a network request
            // You would replace this with your actual logic
            yield return new WaitForSeconds(1);

            // Assert: Replace with your actual assertions
            Assert.IsTrue(true);
        }

        // Parameterized Tests
        [TestCase(1, 1, 2)]
        [TestCase(2, 2, 4)]
        public void AddNumbers(int a, int b, int expected)
        {
            Assert.AreEqual(expected, a + b);
        }

        // Async Test
        [Test]
        public async Task ExampleAsyncTest()
        {
            await SomeAsyncMethod();
            Assert.IsTrue(true);
        }

        private async Task SomeAsyncMethod()
        {
            await Task.Delay(1000);
        }
    }
}