Difference between Unit Testing and Integration Testing
Published: 2020-05-20 10:55:10

"In the software development lifecycle (SDLC), there are two complementary testing practices that are essential in the development phase. These two testing practices are commonly known as unit testing and integration testing. Unit testing ensures in evaluating every code that is written for a particular feature, while integration testing ensures that each module after integration functions effectively. Both, Unit testing and integration testing are the first two testing practices in the SDLC. They have significant importance in delivering quality-assured software."

In today’s digital world, enterprises are effectively planning to deliver software faster in order to compete with the business markets. However, delivering faster is not the only factor to succeed in the market, it is even essential to deliver a quality-assured software application. To make this achieved, it is crucial for the teams to follow the best software testing practice, as testing not only helps to deliver faster, it even validates the quality of the developed application.

In Software Development Lifecycle (SDLC), the software is not developed with the help of one developer. Software is divided into several modules and these modules are distributed among different development teams. And, from here, the stages of testing start. When the modules are developed and leveled up for performing functional testing, then it is known as unit testing. And, after developing all the modules, integrating the modules with other modules is known as integration testing. These two testing practices have a great impact on software testing methodology and it is necessary to understand for achieving quality-assured software.

<h2>What is Unit Testing?</h2>

This is the first testing practice for every software application, where instead of testers, developers are involved in performing unit tests. In this testing process, single modules are tested and then the functionality of this small code is validated.

Unit testing is commonly known for separating the system components and validating their functionality individually. However, this is not the only objective of unit testing, it focuses on several other factors too such as:

• For finding the bugs at the earliest in the development cycle
• It helps to provide a solid framework to understand and handle the APIs
• With the concept of testing every unit, this enhance in improving the code reusability
• This testing practice assures to remove the bottlenecks related system failures

<h2>What are the benefits of Unit Testing?</h2>

• Assures to lower-down the maintenance cost by finding and fixing the bugs at the earliest
• Helps to maintain the behavior of the units
• Assures to find the bugs or the defects that can break the design contracts
• There is no need for having skilled teams manage or write test cases

<h2>What is Integration Testing?</h2>

In this integration testing, multiple modules are tested and then integrated to validate if they are functioning as expected or not when they are together. Integration testing is practiced after unit testing and before system testing.
It is performed after all the modules are integrated with the unit tested. This method involves testers, and the teams focus on the integrated functionality rather than the application’s design.

Integration testing is further classified into different types such as:
• Top-down integration testing
• Bottom-up integration testing
• Big-bang integration testing
• Mixed or Sandwich integration testing

<h2>What are the benefits of Integration Testing?</h2>

• Helps to assure faster testing process
• It improves the code coverage
• It is efficient in identifying system-level bugs
• Assures to find bugs at the early stage of application development

Conclusion:

Unit testing and <a href="https://www.testingxperts.com/blog/integration-testing/">integration testing</a> are the first two testing practices in the SDLC. These have significant importance in software testing and help in assuring many benefits such as faster testing process, enhanced code coverage, early bug detection, saves maintenance cost, etc. To achieve the best testing strategy in software development, leverage software testing services from an independent testing services provider.

About the Author:

I am a technical content writer, interested in writing articles on the latest IT related topics. In this article, I tried to share my views on the differences between unit testing and integration testing.