What is Unit Testing? Advantages and Disadvantages

Unit Testing

In this world of technology, software plays an important role in the life of any human being. We cannot live a single day without using the software.

Be it for contacting anyone or be it for entertainment, the software has become an inevitable part of human life. Sometimes, this software needs to be tested and verified to determine whether it is worth using.

This testing also helps the developers find any problem in the application or software before it is launched and fix it. Among all types of software testing, there is a technique known as Unit Testing.

This article will provide you with every detail that a person wants to know about Unit Testing.

What is Unit Testing in Software?

The unit testing definition has been said to be a part of the software development process. Every small part of an application or software, known as units, is scrutinized so that the details can be modified and made up to the mark before any common public uses it.

A company’s developers and testers do this testing method while the software is still under development. The main motive behind unit testing is to make separate parts of the code so that it can be tested and determined to work the same way it has been designed.

This testing process is a very important part of the software development process because, if done correctly, the flaws can be detected early and become very difficult to discover later when the code has been written completely.

In an SDLC or V model, unit testing is just the first testing level, performed before integration testing.

As mentioned above, this testing is usually done by the developers themselves. But sometimes, due to the reluctance of the developers. These engineers are hired to do a quality assurance test to complete the job. It was all about unit testing definition.

Why perform a Unit Test?

The Software Testing process is very detailed and lengthy. Units are just a part of the codes that the developer is writing. There are many reasons behind performing a Unit test.

  • The main reason behind performing unit testing is to make different parts for the written code so that it can be tested and the testers or developers can ensure that the code is working properly.
  •  If any problem is found, the developers can easily solve them early, and the final product does not show any problem in the final version and gets delivered to the clients.
  • If the problems are identified earlier, the final version’s chance of finding unit errors reduces. It is the main reason behind performing unit testing. Besides that, the debugging procedure becomes easy and simplified when developers perform unit testing.
  • When any bugs or errors are found, the engineers can easily make the required changes in the code base, and the code can be reused by the developers when they move to a new project.

Types of Unit Testing

Types of Unit Testing
Image source: Winkklix

Every quality analyst widely uses two basic types of unit testing. Sometimes people get confused with the techniques. The techniques of unit testing are completely different aspects. There are mainly two different types of Unit Testing – Manual and Automatic.

Manual Testing

Manual Unit Testing mainly includes the process of manually testing software, that is, without the help of any automatic tool or script.

During this testing, the tester generally acts as a real-time user. It checks the software by running it on their device so that the person can identify any bug or unexpected behavior.

This software unit testing is a fundamental testing process as it can find both visible and hidden defects in the software. It is a mandatory testing stage for any newly designed software.

It requires knowledge of manual testing techniques and does not require any automatic testing tools. The person who is testing the software manually uses test plans, test cases, or test scenarios to test software to ensure the completeness of testing.

Manual testing also includes the exploratory testing process, as testers explore the software to identify errors.

The engineer learns the user’s perspective if the software is tested manually. It helps to note down the correct test cases of the application and give some quick feedback on the application. 

Automatic Testing

Automatic Unit Testing, also known as Test Automation, is when the tester scripts sequences and uses different software to test the product and find any dispute in its behavior.

These types of testing can repeatedly run at any time of the day. This process mainly involves the automation of a manual process. This type of software unit testing is mainly done with the help of automatic testing tools.

Automation Testing is very useful to re-run the test scenarios quickly and multiple times, which has been performed manually in manual testing. The tools execute the software examination, provide the report outcomes, and compare the results with the test runs performed earlier.

Regression and automation testing are also used to test the application and type of software from some points of view, such as load, performance, and stress.

It helps increase the test coverage, has improved accuracy, and saves time and money compared to Manual Software Testing. This unit testing also fits properly with continuous testing, continuous integration, and delivery of software development practices.

There are also some techniques of Unit Testing which are widely followed by every quality analyst around the globe – White Box and Gorilla Testing.

White Box Testing

In this testing technique, the tester can easily access the internal structure of the application that has been developed. With the help of this technique, a person can easily find out the problems present in the application’s design.

Gorilla Testing

While using Gorilla Testing, the tester and the developer check the module of the software or application very minutely. Gorilla Testing is very useful for checking the robustness of your application. The tester focuses on a single module of the software.

How to do Unit Testing of a Software?

How to do Unit Testing of a Software?
Image source: Codementor

Generally, there are three stages in Unit Testing – plan, cases, and scripting, and then the Unit Test itself. In the first step, the unit test is prepared and reviewed properly. In the next step, the test cases and the scripts are made, and the code is tested.

Test-driven development (TDD) generally requires the developers first to write down the units that are failing the test. Then the code is written, and it is executed. This process continues until and unless the code passes the test. Thus the TDD helps to form an explicit and quite predictable code base for the developer.

The testers check the case in a completely independent environment to ensure the lack of dependencies in the code. This testing method is used while the application is still under development by the developers and the quality analyst staff.

The developer must maintain criteria to verify every test case and use a testing framework to report any failed tests. It does not mean that the developers perform the tests for every line of the code because that would become very time-consuming.

Instead, they must create tests by focusing on the codes that can affect the performance and behavior of the software.

Unit testing only involves characteristics very important for the units being tested. It acts as a motivation for the developers so that they can modify the source code without having any immediate concerns.

Sometimes, there are some requirements for performing the unit testing so that the developers obey the standards specified by the industry. These standards and rules can specify what techniques they can use for developing the application or the software.

Once every unit is found to be working efficiently. Without any error, it will become easier for the developers to test the larger parts of the code by the next type of testing, which is known as integration testing.

Advantages of Unit Testing

There are quite a several advantages that make software unit testing a very important part of the complete software testing procedure.

Faster Process

It is one of the most important advantages of unit testing. If you add too many designs to the software, it becomes very dangerous and expensive to replace the old design and code. Using the unit testing method saves time and makes the process easier.

Better Code Quality

Unit testing also plays a key role in improving code quality. Suppose the engineers can identify any minor damage while they perform unit tests. In that case, they can fix them, and the code quality can be improved before the experts perform a combinational test for the software.

Easier to find Bugs

Unit testing helps us to identify all types of bugs in the software at an early stage. The developers can then work on the problems first before moving forward. The main advantage is it provides an early resolution to the problems, and no other part of the software is affected.

Focus on the Design

Unit testing allows the software developers to think about software developers to completely focus on the design of the software and what they must do before decoding it. If they check the code in advance, they can explain what the piece of the code is doing.

Code becomes Reusable and Reliable

In the unit testing environment, the code has its own area of responsibility when isolated from one another. It makes the code more reliable since it has been tested in a compact environment. It also makes the code reusable. Thus when the code becomes reusable, it becomes very useful for the developers.

Disadvantages of Unit Testing

Apart from all the advantages of unit testing, this process has some disadvantages. Code testers will inform you all about the problems in the code that the developers can change.

Code becomes Lengthy

While using the Unit Testing procedure, the code that needs to be written becomes very lengthy. You will need to write one or more unit tests depending on how complex the things are. While the test code is quite simple, this testing method is still lengthy.

Sometimes Code Quality is Distorted

Some say this method improves the code quality, and others say it worsens the code quality. If we change the code and add some new code, it can sometimes cause some navigation issues, and you may need to spend more time before you start integration testing.

Low Accuracy Rate

The process of Unit testing is not efficient enough to find all the errors that are present in the program. It is impossible to catch the errors by checking every execution path.

Final Words

No matter what kind of code you are testing, it will be quite helpful if you find bugs and errors in due time.

Work with a good quality analyst team for your unit testing procedure. You can easily cover all the bases in your unit testing process, making it more helpful and effective for the software.