Introduction

Unit testing is a software testing method for testing individual units or software components. The primary goal is to validate that each software unit performs as designed. In front-end development, a unit typically refers to the smallest testable part of an application, like a function, a component, or a class.

Importance of Unit Testing

The primary purposes of unit testing are:

  • Ensures Code Quality: Unit tests check the code's correctness under various conditions, catching bugs early in the development cycle.
  • Facilitates Refactoring: With a reliable suite of tests, developers can refactor code confidently, knowing that tests will catch any inadvertent changes in behavior.
  • Improves Code Design: Writing testable code often leads to better software design, encouraging more modular and maintainable code.
  • Documentation: Unit tests serve as a form of documentation for the code. They demonstrate how the code is supposed to be used and how it behaves under various conditions.
  • Reduces Costs: Finding and fixing defects early in the development process is less costly than fixing them in later stages of the development lifecycle.