How Unit Testing Is Different From Integration Testing?
In the Software Development Life Cycle, various types of methods are used for
QA or software testing, like system testing, acceptance testing, quality
testing, unit testing, regression testing, etc. But the essential ones are
unit testing and integration testing.
In this blog, we will learn how unit testing differs from integration testing,
what consumes more time and money, and how they work. After reading this blog,
your confusion between those will get rectified.
Let’s get started with unit testing first.
What Is Unit Testing?
Unit testing is a part of the SDLC where individual
units or components of a software program are tested to see if they are
functioning as expected. An application’s most minor testable component is a
unit or piece of code. In procedural programming, a unit may be an individual
program, function, procedure, etc., while in object-oriented programming, a
unit is a particular class, module, or function.
Developers usually write unit tests as they are creating code. They are used
to make sure that the code they have written works as expected and to find any
bugs before the code is deployed.
Unit tests can be run automatically, and they can also be run manually. When
they are run automatically, they are typically run as part of continuous
integration or a continuous delivery process.
Unit testing has many benefits, including:
- Finding bugs early: Unit tests can find bugs early in the development process before the code is deployed. It can save time and money as it is cheaper to fix bugs early on.
- Improving code quality: Unit tests can help improve code quality by driving the developer to write high-quality testable code.
- Facilitating refactoring: Unit tests can help reduce refactoring. They can provide a safety net that detects bugs when the code is refactored.
- Increasing confidence: Unit tests can increase confidence in the code by assuring that the code is working as expected.
Why Unit Testing?
Unit testing is a great way to ensure your code works as intended. You can
verify that your code is doing what you expect by writing and running tests.
Additionally, unit testing can help you find and fix errors early in
Unit testing is crucial for a more extensive system’s code. It can help ensure
that changes to one part of the code will not break other parts of the system.
Unit tests can also be run automatically as part of a continuous integration
process, making it easy to catch errors as soon as they are introduced.
Overall, unit testing is a valuable tool for any software development project.
It can help you catch errors early, ensure that your code works as intended,
and automate the testing process.
- Field length (Username and Password)
- Validation of input values
- The login button check – Validation after proper input values
Best Unit Testing Tools
- Quilt HTTP
- Microsoft Unit Testing Framework
- Unity Test Tools
- ABAP Unit
What Is Integration Testing?
Integration testing is a type of QA used to verify a system’s functionality
composed of multiple components or modules. This type of testing is essential
because it can help ensure that the various parts of a system work together as
Integration testing can be performed at various levels, such as component
level, interface level, and system level. Component-level testing focuses on
testing the individual components of a system. In contrast, interface-level
testing focuses on testing the interactions between components. System-level
testing is the most comprehensive type of integration testing and focuses on
testing the system.
Integration testing can be tricky because it can be challenging to determine
when all the necessary components are available for testing. In addition,
integration testing often requires test stubs and drivers, which can add to
the complexity of the process.
Integration testing has three approaches:
- Bing Bang Approach
- Top Down Approach
- Bottom-Up Approach
Despite these challenges, integration testing is integral to the software
development process. It can help ensure that a system is functioning as
Why Integration Testing?
As a software development team, it’s essential to consider the various types
of testing that can be performed on your code. One type of testing that’s
often overlooked is integration testing.
Integration testing is a type of testing that verifies how different
components of your software interact with each other. It is essential because
you want to ensure that your software will work as intended when all the
pieces are together.
Integration testing is that it can help to identify potential problems early
on in the development process. It can save you time and money in the long run,
as you can fix issues before they become too costly.
Integration testing can help to ensure that your software is scalable. It is
essential to ensure your software can grow with the business.
- Testing the welcome message after entering valid values by pressing the login button
- Users should direct to the home page after entering valid data by pressing the login button
Best Integration Testing Tools
- H2 Database
- JUnit 5
Unit Testing vs. Integration Testing
|Unit Testing||Integration Testing|
|It’s a type of testing of small code to see if it’s working or not.||It|
|tests different modules to see if they are working together or not.|
|Checks single component of an app||The behavior of various integration|
|modules is called integration testing.|
|It covers small code or units; a short code is written for a single testing|
|class for unit tests.||It covers the whole app and requires more effort to|
|combine all units.|
|No dependencies on the testing unit.||Dependent on external systems like|
|hardware allocation, databases, etc.|
|It is the first type of testing in the Software testing life cycle.||It’s|
|carried out after unit testing and before system testing.|
|There are no sub-divisions of it.||Integration testing is divided into|
|three types: big bang, top-down & bottom down.|
|Module specifications are the first step in unit testing.||The interface|
|specification is the first step in integration testing.|
|Under unit testing, the detailed visibility of the code is covered.||Under|
|integration testing, the visibility of the integration structure is included.|
|Focuses on the functionality of units.||Focuses on modules and how they|
|interact with each other.|
|It comes under the white box testing type.||It comes under both white and|
|black box testing.|
|Cost-friendly maintenance.||Expensive maintenance.|
|It’s easy to find errors.||It’s difficult to find errors.|
|Executed by the developer.||Executed by the test team.|
- Unit testing is a method for testing individual pieces of code, while integration testing will help to verify the connection between two or more modules
- Unit testing problems can be fixed right away, but integration testing problems take longer and cost more to fix because it’s harder to pinpoint the exact location where a bug first appeared
- As written code is tested during unit testing, access to the source code is necessary. However, since integration testing examines the relationships and interfaces between modules, access to the source code is not needed
- Integration testing is white and black-box testing, while unit testing is white box testing.
- In software testing, quality assurance, or quality testing, both unit, and integration testing are essential.
- Both are integral parts of the development process; large numbers of bugs/errors can happen without unit testing or integration testing.
The Cost: Unit Testing vs. Integration Testing
The cost of QA and software testing, especially sub-tests: unit testing and
integration testing, can be high. However, the benefits of having high-quality
software can be even higher. When done correctly, quality testing can save you
time and money in the long run.
Unit testing aims to test individual components of your software to ensure
that they are working as expected. This is important because it can help you
find and fix bugs before they cause major problems. Integration testing is a
bit different; it tests how various components of your software work together.
It is essential because it can help you find and fix bugs that only occur when
specific parts are used together.
Both unit testing and integration testing can be time-consuming and expensive.
However, the benefits of having high-quality software can be even higher.
Quality testing saves you time and money in the long run by helping you find
and fix bugs before they cause major problems.
All tests are necessary for a software development
unit testing or integration testing. It’s all about ensuring that each
code/unit works correctly and that each module interacts smoothly without
No doubt, unit testing is superfast, but integration testing is also integral.
Integration testing consumes time and money but assures high-quality software
in the long run.
I hope you now have a clearer vision of unit testing and integration testing
and how unit testing differs from integration testing. Thanks for reading.
- Mobile App Development (297)