In TC-Lite, a TestFixture is simply a class containing tests. A separate instance of the fixture class is created for each test case that is run and is disposed when the test case completes. That shortened life span means that the state of the fixture does not persist beyond a single test.

If you come to TC-Lite from NUnit this is a big change but it's actually the way most xUnit-style test frameworks work. Using a separate fixture instance for each test case, makes it harder for tests to interfere with one another. It also makes parallel execution a lot simpler and reduces the size of the framework.

To work well within this model, fixtures must be very lightweight. Although the fixture constructor may be used to initialize instance members, this should usually be limited to those needed by every test. In rare instances, disposal of the fixture may be required. TC-Lite will call Dispose for any fixture class, which implements IDisposable.

A TestFixture is normally recognized by the fact that the class contains TestCases. It may optionally be indicated by use of the TestFixtureAttribute on the class.