A xUnit-style library contains the following components.
Test case class : It is the base class of all test classes written in test modules.
Text fixtures : These are the methods that run before and after the execution of test code.
Assertions : These are the functions or methods that check the behavior of variables being tested.
Test Suite: It is the collection of related tests that can be executed together.
Test Runner: It is the block of code that runs the test suite.
Test result formatter : It formats the test results output in human readable formats like plaintext, HTML, XML, etc.
