Unit Testing is a part of software testing where testing is performed on small isolated parts of the code. The objective of Unit Testing is to isolate small portions of application code that could be individually tested and verified, provided the isolated code units are developed correctly.
- It is performed by the development Team in the SDLC process.
- There are a set of valid inputs that would be provided to a unit of code to verify whether the expected values are returned or not.
- At the same time, invalid inputs are also provided to check how the system would handle errors.
Unit Testing tools are used for this reason i.e. they would help in reducing the number of bugs and as well as improve the security aspect of our software design. These tools test the source code.
Criteria For Choosing Unit Testing Tools
Some of the most important criteria for choosing Unit Testing Tools are as follows:
- Learning Curve of the tool: When Picking a tool one should be wary of the learning curve of the tool. From the tool's learning curve one should know whether the time one is willing to invest would be worth it or not.
- Stability as well as the customer support of the tool: A good unit testing tool should have great customer support as well as online resources and documentation to help the users if they get stuck.
- Simple Graphical User Interface (GUI): The tools should have an excellent reporting Interface so that clear reports once generated would help the users to conclude the test results in fewer time intervals.
- Ability to test data input data for load testing or difficult test scenarios: The unit testing tool should be such that it supports test data input from various types of data files such as Excel, and XML. This would help the automation Testers in a great way.
- Ability to maintain the test scripts: In automation testing, the Record and playback feature is extremely important and the ability of a tool to maintain and record scripts would be a great solution for the Automation testers.
- Types of Testing supported: The unit testing tool should be such that it could support maximum testing types namely Unit, regression, etc. The tool should be good enough for automating our complex test case requirements.
- Allocated Budget: Above all, the budget should be carefully considered before coming to a decision.
Why Choosing Correct Unit Testing Tool Important?
Choosing the correct unit testing tool is important for the following reasons:
- Ensures that every system component is benefitted from achieving better product quality.
- The debugging process is simplified.
- Code Refactoring and debugging of the code becomes simpler.
- If bugs are present, they would be defined earlier in the SDLC process.
- Bug fixing costs would be reduced significantly
Some Common unit testing tools
Let's discuss each of these tools in detail.
1. JUnit
JUnit is a Java-based open-source unit testing framework used to test small/large units of code. For running JUnit tests, we don't require creating class objects or defining the main method. Junit provides an assertion library that is used to evaluate test results. Annotations of JUnit are used to run the test method. JUnit is extensively used to run the Automation suite having multiple test cases.
Key Features:
- It provides a test-driven development.
- It has support for Maven and Gradle integration.
- It has support for the execution of Tests in groups.
- Can be integrated with popular IDEs like Netbeans, Eclipse, IntelliJ, etc.
- It has Fixtures that provide an environment for running repeated tests.
- Using the @RunWith and @Suite annotation Test suite annotations we can run unit test cases.
- It provides Test runners for executing the test cases.
2. NUnit
NUnit is a .NET-based open source unit testing framework that has directly inherited most of its features from JUnit. NUnit has extensive support for Test-Driven development like JUnit and has most of its features similar to JUnit. NUnit provides a console runner that helps in the batch execution of automated tests.
Key Features:
- It has support for multiple assemblies.
- Extensive support for Assertions
- It provides various attributes for running tests with different parameters.
- It has support for data-driven testing.
- It has support for Microsoft family languages-.NETcore, Xamarin forms.
- We can run parallel tests too using NUnit.
- For running batch tests, a console runner is present that is provided by NUnit.
3. TestNG
TestNG stands for Test Next Generation. TestNG is a robust framework as we can have full control over the testing and execution of Test cases. It has features from both JUnit and NUnit. TestNG supports a variety of test categories which includes unit, functional, integration, etc, with easier-to-use functionalities and hence considered one of the most powerful unit testing tools.
Key Features:
- It has support for testing integrated classes.
- It provides HTML reports and generates logs.
- It has support for the parallel execution of test cases.
- It can read keywords/data from logs.
- It has an inbuilt exception handling feature.
- It has support for multi-threaded execution.
- It is completely object-oriented and therefore has easier annotations
- All the test configurations are XML based.
4. LambdaTest
LambdaTest is an AI-powered test orchestration and execution platform that allows developers and testers to perform automated testing at scale across 3000+ real browsers, devices, and operating system combinations.
Features:
- Supports automated testing with popular frameworks across real desktop and mobile environments.
- Speeds up release cycles using the HyperExecute platform.
- Enables visual testing using the AI-powered SmartUI platform.
- Provides geolocation testing from 53+ countries and cities.
- Offers 120+ integrations with CI/CD, project management, and automation tools.
- Delivers detailed test insights using AI-powered Test Analytics.
5. PHPUnit
PHPUnit is a programmer-oriented unit testing framework for PHP. It is based on the xUnit architecture, similar to frameworks like JUnit and NUnit. PHPUnit is executed through the command line and cannot be run directly in a browser.
Features:
- Supports code coverage analysis and mock objects.
- Provides support for test-driven development (TDD).
- Supports logging and reporting using xUnit architecture.
- Includes strong support for mocking objects.
- Offers a wide range of assertions for validating outputs (including XML assertions in older/legacy use cases).
- Provides error handling support in modern versions.
- Test cases can be extended based on project requirements.
- Supports generation of multiple test reports.
6. Mockito
It is a unit testing framework in Java. Mockito is mainly used to mock interfaces so that dummy functionalities can be added to mock interfaces for unit testing. Mockito helps in creating mock objects easily. To obtain this, Mockito uses Java Reflection API for creating mock objects for a given interface.
Key Features:
- Methods like verify() and mock() have extensive use in testing Java applications
- Has support for annotation feature for testing mocks.
- Mockito is a powerful mocking framework as it allows us to not write mock objects of our own.
- Better readability for error messages.
- It supports safe refactoring, exception support, returns value support, etc.
- We do not need to write mock objects on our own.
7. Cantata
It is a unit testing tool in C/C++. It helps developers to verify standard-compliant or business-critical code on specific hosted platforms. As C/C++ is closer to hardware, therefore Cantata finds extensive application in embedded systems. For this reason, It can be easily integrated with desktop compilers and embedded target platforms. It also checks the testing requirements compliance by automating text executions.
Key Features:
- It can automate Regression testing or Continuous Integration
- It generates and edits test reports written in C/C++.
- Particularly helpful for large data sets.
- It has support for test-driven development
- Many types of testing like Object-oriented testing, isolation testing, and structural testing can be performed.
8. Karma
Karma is a JavaScript testing tool that runs tests in real browsers using the Node.js environment. It includes an in-built test runner that starts a web server and executes JavaScript test files in the browser.
Key Features:
- Mainly used for testing front-end applications, especially Angular applications.
- Provides a test runner to execute tests directly in the browser.
- Supports easy debugging and integration with CI/CD tools like Jenkins.
- Supports test-driven development (TDD).
- Helps run tests across multiple real browsers for better compatibility.
9. Mocha
Mocha is a JavaScript testing framework that runs on Node.js and simplifies testing of asynchronous JavaScript code. It provides powerful features for mapping exceptions to correct test cases and supports organized execution of tests.
Key Features:
- Supports test coverage reports and test duration reporting.
- Provides a JavaScript API for running tests.
- Supports running Node.js tests in parallel.
- Supports asynchronous test timeouts.
- Compatible with any assertion library.
- Provides support for Node.js debuggers.
10. TypeMock
TypeMock is a unit testing tool for .NET and C++ legacy applications. TypeMock Isolator++ allows developers to test legacy code without modifying production code and provides a powerful mocking framework with extensive code coverage support.
Key Features:
- Provides simple entry methods that do not require changes to legacy code.
- Offers excellent readability and extensive code coverage.
- Supports mocking code without modifying the original implementation.
- Allows faking of static methods, private methods, and members.