Testing Fundamentals

Testing

• Testing is the process of evaluating a system or its component(s) to find whether it satisfies the specified requirements or not.
• It involves the execution of a system or application to identify any gaps, errors, or missing requirements in the software.

Levels of Testing

• No specific information provided

Unit Testing

• Unit Testing is a software testing technique where individual units or components of a software application are tested in isolation from the rest of the application.
• It provides benefits such as automated testing, early detection of bugs, documentation, code refactoring, collaboration, and regression testing.

JUnit5

• JUnit5 is an API to write tests, mainly for use by developers.
• It provides a mechanism for discovering and running tests, and an API to allow easy interaction with IDEs and tools.
• JUnit5 consists of JUnit Platform, JUnit Jupiter, and JUnit Vintage.
• It offers benefits such as annotations and extensions, parameterized tests, backward compatibility, improved assertions API, and improved IDE support.

Test Discovery

• Test classes should follow the JUnit 5 naming conventions, ending with "Tests" or "TestCase".
• Test methods should be annotated with @Test or @ParameterizedTest.
• Test classes and methods are not required to be public, but they must not be private.

JUnit Annotations

• @BeforeEach: before each test
• @AfterEach: after each test
• @BeforeAll: before all tests
• @AfterAll: after all tests
• @Test: denotes a test method
• @Tag: used to filter tests
• @DisplayName: sets a custom display name for a test
• @Disabled: disables a test
• @Enabled: enables a test
• @TestFactory: defines a test factory
• @ParameterizedTest: runs a test with different parameters
• @RepeatedTest: runs a test repeatedly

Code Coverage using Jacoco

• Code coverage is a software metric used to measure how many lines of our code are executed during automated tests.
• Add the jacoco plugin in your pom.xml file to use JaCoCo.
• JaCoCo offers a simple way of declaring minimum requirements that should be met, otherwise the build will fail.
• Run $ mvn clean test jacoco:report to see the coverage report.

Mocking using Mockito

• Mocking is a technique used in testing to create objects that simulate the behavior of real objects.
• It helps isolate the code being tested by replacing real dependencies with objects that can be controlled.
• Stubs: objects that provide predefined responses to method calls.
• Spies: objects that record the interactions with the real objects they are spying on.
• Double: a general term for any object used as a substitute for a real object during testing.

Test Driven Development

• Test-Driven Development (TDD) is a software development approach where tests are written before the actual code.
• The development process in TDD follows these basic steps:
  • Write a failing test that describes a piece of desired functionality.
  • Write the minimum amount of code needed to make the test pass.
  • Refactor the code to make it clean, improving its design without changing its behavior.
  • Repeat the process.

CI/CD (Continuous Integration/Continuous Deployment)

• CI/CD is a set of best practices and a software development approach that aims to enhance the efficiency, quality, and speed of software development.
• It involves the automated integration of code changes, testing, and the continuous deployment of applications.
• Benefits of CI/CD include:
  • Faster Delivery
  • Higher Quality
  • Consistency
  • Collaboration
  • Feedback Loop
• Tools for CI/CD include GitHub Actions, Jenkins, TeamCity, CircleCI, and GitLab CI/CD.