Updated March 30, 2023
Introduction to ScalaTest
The following article provides an outline for ScalaTest. Testing is a very important part of the application development. To test our application, we can write various test cases to validate them; this approach is know as the test-driven development. By testing our application thoroughly, we can make sure that it will not cause any serious problem in the production. We have several tools to test our application; one of them is the Scala Test library which is used to provide support to test our application.
How to Perform Testing in Scala?
We can perform testing in scala by using the ScalaTest library. This library provides us with large support for the various integration test as well. Also, this library can easily be used with the various editor like IntelliJ, Eclipse and many more to make the development fast and easier. Play framework also provides good support to use this library with it. Whenever we develop any application, we have to test it before delivering it to its owner. So in the programming language, we can perform this by using various tools available, which makes our work sometimes automated and faster to execute.
1. We can use this with the play framework.
ScalaTest can be used with the play framework; also, it provides support for various integration to test the application as we know that we keep our test classes inside the test folder only. In every programming language, we have this like java also. Inside this folder, we can create our test classes and place the code inside them. We can also mock our data whenever we want. For this, it provides us integration support as well. So now we will see how to configure this in the play framework.
2. In order to use this in our application, we have to include one dependency in our project to use this library.
Below find the library name to include it:
This is the dependency that is required to include; after that, we can specify the version as well for this. All this changes will be done in the build.stb file. After including the dependency, we can now create the test classes in Scala to test our application.
So here we are using the ScalaTest tool to test our application, now we will see how to create a test class in scala using the ScalaTest library:
- Create a simple class in scala like we normally create, but this class should extend the PlaySpec class from the ScalaTest library.
- Also, we have to include the package as well, like this ‘import org.scalatestplus.play._’, then only we can test our application, and the program will compile.
If you want to assert something, then we can use ‘MustMatchers’ from the ScalaTest library. MustMatchers is used to compare the test result in java; we use assert, but here we are using MustMatchers from scalatest. So after the test case, we can return something based on the result we obtained. In this way, we can implement this in our application.
Benefits for Using Test in Scala
- To test our application, we make sure that the functionality is working fine; it makes our application test-driven, which means any error or exception can be caught at the time of build only.
- Test cases or test tool makes our application error-free. Also, they are very easy to write and read.
- To implement this in scala, we have a scalatest library, which makes it easier to maintain and implement.
- By writing test cases, we can detect the error at the early stage of the development; this is also beneficial for developers to save their time.
- Test-driven application can be easily scalable also, and different developers can work on them.
- Also, we have a mock data creation library, so we do not need to deal and test with the real-time data; we can easily mock out data.
Testing Tools for Scala
As of now, we have already seen that we have a scala test to test our application. This is the tool which comes up with so much support for testing in scala. We can easily use this with the play framework as well. To use this in our application, we have to include the dependency, and it provide us support for various integration test.
- JUnit: ScalaTest provides us with the support to write the junit test cases.
Above mentioned tools can easily be used with the scala test library. In this way, we can write or create a test in scala.
We can also mock data in test cases see below:
- Mockito: By the use of this, we can mock the data because every time it is not possible and not recommended, you create the instance of the service classes just to test the application so we can mock the data without being using the controller, service classes in the test classes. This can be achieved by using the Mockito api in scala. This is a very common api to use in programming language while dealing with the mock data in test cases. We can also test our controller classes in scala, for this scala test library provide us Unit testing controllers which can easily be used to test them.
Conclusion – ScalaTest
So by testing of our application, we make it less suspect to error, and it will also be easy to detect an error in the application. Nowadays, all applications are built using the test-driven approach because it is reliable and easy for developers to track bugs. Also, we have some tools available which make it even easier to test them.
This is a guide to ScalaTest. Here we discuss the introduction, how to perform testing in scala? Benefits and testing tools, respectively. You may also have a look at the following articles to learn more –