Published: 09 Jun 2020
Unit Testing – What is Its Importance in Software Testing?
Last Updated: 16 Mar 2022
Content 1. What is Unit Testing? 2. Why Unit Testing is important to perform? 3. What are the benefits of Unit Testing? 4. What are the types of Unit Testing? 5. Who performs Unit Testing? 6. How to do Unit Testing? 7. What are Unit Testing best practices? 8. What are some important Unit Test frameworks? 9. Unit Testing Vs Integration Testing 10. Conclusion
A typical unit test consists of three phases which include the first initialization phase where it initializes a small piece of an application it wants to test. The second phase is the addition phase where it adds a stimulus to the system under test and finally, the third phase is the result phase where it observes the resulting application behavior. Evidently, if the observed behavior is consistent with expectations, then the unit test passes else it fails. This indicates there is a problem somewhere in the system under test. These three test phases are named as Arrange, Act and Assert or commonly known as AAA.
Unit Testing is the software testing technique where a group of software program components or modules are tested individually. This technique effectively helps in validating the accuracy of a section of code by considering stubs, mock objects, drivers, and unit testing frameworks. Since it is practiced at the initial testing phase, this testing technique assures to identify and fix the bugs at the early stage of SDLC even before they become expensive for the enterprises to fix when identified at a later stage.
Some developers may attempt to save time by performing minimal unit testing, or when unit testing is skipped, it obviously leads to higher defect fixing costs during system testing, integration testing, and even beta testing when the application is completed.
Moreover, in addition to these, unit testing helps the development teams to understand the code base, validate the correctness of the developed code, reuse the code, and to make the changes faster in the code.
With a proper unit testing practice in place, the developers and testers can help to save time as bugs can be identified early in the process as it is the initial phase of testing. And, skipping or limiting the practice of unit testing can adversely increase the defects and it becomes complex to fix them at a later stage. Hence, it is essential to practice unit testing at the initial stage of the software testing process before planning for the integration testing.
– Isolates a section of code and validates its correctness
– Helps in identifying and fixing the bugs at the early stage of the SDLC process
– Assures to reduce the cost as bugs are resolved at the earliest
– Helps the developers to improve the design by allowing refactoring of the code
– Assures in simplifying the debugging process
– With the proper unit testing practice, components that are integrated after the build can assure in achieving a quality product
In order to practice unit testing with the manual testing method, it is essential for the unit testers to get a step-by-step instructional document. However, considering the efforts needed for manual testing, automated unit testing is often preferred by most enterprises.
– The developers write the code in the application for testing the function and would wait for the application to get deployed for removing the test code
– The code is then isolated by the developers to validate the dependencies between the code and other units. This way of isolating the code helps in identifying and eliminating the dependencies.
– Developers significantly make use of Unit test frameworks or unit testing tools for developing automated test cases.
– While executing the test cases, the unit test frameworks help to flag and report the failed test cases. Also, based on the failures in the test cases, the unit test frameworks help to stop the related testing.
Integration testing is the second software testing phase conducted after unit testing. In Integration testing, the small modules that are individually tested in the unit testing are integrated or combined to test the functionality of the modules when they are together. However, to understand these two testing phases more easily, their major differences have been listed below.
It is the initial testing phase in SDLC. | It is practiced after unit testing and before system testing. |
In this testing practice, the smallest piece of the code is tested. | In this method, different modules are combined or integrated to test if they are working together. |
Unit testing focuses on testing the functionality of the individual units | Integration testing focuses on identifying the bugs that are raised by integrating different modules. |
Unit testing is a type of white-box testing. | Integration testing is a type of black-box testing. |
It is performed by software developers or even by testers. | It is performed by testers. |
Maintaining the unit test cases is cheaper. | Maintaining the integration test cases is expensive. |
It is easy to find bugs in this method. | It is comparatively difficult for identifying issues in this method. |
Unit testing is started with module specification. | Integration testing is started with interface specifications. |
Businesses can be ensured of bug-free and quality software if software testing is performed effectively from the initial stage of product development. Software testing has to be taken up from the very first stage, i.e. from the code level itself; and this can be achieved when software developers perform the unit testing.
Unit testing is the earliest testing practice that focuses on the code. With this testing approach, small modules of the program are tested individually. This approach benefits the teams in many ways such as early bug detection, fixing the code before they become expensive to resolve in the SDLC. Hence, practicing unit testing is essential for businesses to ensure that the developed software is bug-free and quality is assured from the initial stage of SDLC. Leverage unit testing services from independent QA testing services provider to make your software get high-quality. Talk to us
1. Integration Testing: What is,Types, Tools, Steps to Perform 2. Automated Software Testing – What, Why, Tools, Challenges 3. UAT Testing Complete Guide 4. Mobile Testing Practices You Should Know 5. What is Agile Methodology? 6. Selenium testing Tutorials for Beginner’s
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