What is the difference between functional and integration testing?
Are functional vs integration testing the same? After unit testing, integration testing ensures that different components work together.
However, functional testing also evaluates the system as a whole to verify functionality conformance. How do these two testing types differ, and when should each be used?
Both functional and integration testing are important steps in ensuring that your software works as expected, but they focus on different levels of testing.
Functional testing specifically verifies that each function or feature of the software behaves according to the specifications. It’s usually higher-level than unit tests, checking for expected outcomes from the user’s perspective.
In contrast, integration testing focuses on how different components or modules in the system interact with each other. It’s about testing how well these individual pieces work together when combined, which may not be covered by functional tests alone.
To add on, functional testing checks if a feature works in isolation from a user’s standpoint, which often involves real-world scenarios. It’s often about validating the software’s behavior from the outside-in.
For example, you might test if a login button triggers the correct action. On the other hand, integration testing is more about ensuring that separate systems or parts of the application, like a database or API, function together. It’s not just about each part working individually, but how they communicate and function as a whole.
Exactly, both testing types are important but serve different purposes. Functional testing tends to focus on individual features, typically validating whether or not those features meet business requirements or end-user needs.
In contrast, integration testing is about the communication between these features or modules and ensuring they work together seamlessly, especially when external dependencies like databases, APIs, or services are involved.
So, functional testing might test a single endpoint, while integration testing checks if that endpoint interacts correctly with the database or other services.