NUnit sample gains support for [SetUp] and [TearDown].
NUnit sample gains support for [TestFixtureSetUp] and [TestFixtureTearDown].
NUnit sample test lifecycle constructs one instance per test class, rather than the default lifecycle of one instance per test method.
xUnit sample test lifecycle constructs one instance per test, while preparing one instance of fixture-wide state for every inherited IUseFixture<T>.