Know Everything About Unit Testing

Software developer

What Is Unit Testing

Unit testing ensures that each small, testable chunk of code functions as intended before an organization can release the entire project to the public. Moreover, it helps pinpoint which code might be at fault if the application breaks. Running the tests each time you change the codebase is a great way to ensure that you aren’t introducing any new bugs.

Unit testing follows the principle that you can break even the most complex software into smaller, more manageable pieces. If we can confirm that each unit functions as intended, we can rest assured that the application as a whole will do the same. Since functions typically represent the smallest tested chunks of an application, unit testing typically takes the form of functions verifying the correct operation of other functions.

These terms can be perplexing, as “functional tests” refers to a distinct subset of software testing that aims to verify an application’s overall behavior against a predetermined set of criteria.

Developers perform integration tests to ensure that several modules or components of a system function together as intended and fill the gap between functional and unit tests.

How Does Unit Testing Benefit You

The primary advantage is improved software quality, measured in fewer production issues, which results from finding problems earlier in the development cycle. Although each unit test only covers a small part of a function, combining these tests allows us to cover various use cases. This ability means that unit testing automation significantly reduces the likelihood of problems in a codebase.

A further benefit of a well unit-tested software is its ability to guarantee non-regression or that new functionalities do not compromise the performance of previously-implemented functionality. If it happens, the test runner will instantly report it, allowing you to fix the problem without delay. Working with preexisting, unfamiliar code is a huge assistance because it lightens the developer’s load and assures them to release their work.

The results of automated unit testing also serve as helpful reference material. A well-written test demonstrates the expected behavior of updated or new code and is a valuable resource for future programmers who may wish to implement the same or similar functionality. This aspect is especially true with dynamically typed languages like JavaScript, where it might take effort to guess the anticipated format of an input or result.

Last but not least, implementing unit tests is a great approach to push yourself to evaluate and think critically about your code, which can help you identify implementation issues or motivate you to begin the refactoring you haven’t started.

Unit Testing Best Practices

Write Unit Testing During Development, Not After

Unit tests are the lowest in the testing pyramid, as developers conduct them early in the development cycle. As a result, they function most effectively when used in tandem with development instead of after.

Establishing unit tests promotes clean code output and early bug detection.  The resulting code may not be testable if developers write tests toward the end of development. However, if developers write tests in parallel with production code, you can evaluate them alongside production code, improving developers’ understanding of both sets of code. It also enhances the longevity and scalability of the unit testing procedure.

Reason Less While Testing

The likelihood of finding bugs in your test suite rises when you use manual string concatenation or logical conditions. Tests should center on the desired outcome rather than the implementation details.

Using conditional statements like for, while, if, switch, and more will make your tests harder to read and understand. If logical questions are part of the test, you should break up the test into two or more parts.

It Is Best To Avoid Interdependencies

Due to their interdependencies, tests are difficult to execute and troubleshoot—the Test Runner runs multiple unit tests in parallel. Every test case has its dedicated setup and teardown steps to ensure no dependencies between tests.


Unit testing is fundamental to every software development process, which examines and verifies code in its smallest, most independent parts.

Developers performing unit tests aim to verify their app’s performance, ensuring each component works correctly. There are many positive effects of unit testing.

However, its absence can generate problems that can significantly impact the software and inevitably impact the SDLC. It also guarantees the highest possible program performance by ensuring that every component functions as it should during development.

Organizations look toward unit testing tools to help perform effective unit testing. HeadSpin can help you improve all your automated testing needs. Its comprehensive AI solution gives users detailed insights into app functionality. It also gives its users suggestions on how they can fix issues identified by the platform quickly and efficiently.

Moreover, it gives users access to SIM-enabled, real devices to get the best testing experience. Reach out!