TechnicalPig🐷: How should you test your application?

Smoke Testing

Smoke testing is a high-level, quick check to ensure the basic functionality of the software, acting as a gatekeeper.

• Purpose: Smoke testing is a preliminary test to ensure that the most fundamental functionalities of a software application are working. It's like a quick health check-up to confirm that the application can proceed.

• Scope: Smoke tests are broad but shallow, covering the critical paths of an application without going into deep functionality. They verify that major features are operational but do not test them in detail.

• Frequency: Smoke tests are performed on new builds to ensure that the build is stable. They can be conducted as often as new builds are created.

• Execution: Smoke tests are generally automated to quickly assess the stability of a build. They are designed to be simple and fast to execute.

• Outcome: The main goal is to verify that there are no "showstopper" defects. If a build fails a smoke test, it is usually rejected and sent back for revision.

Integration Testing

Integration testing focuses on the interaction between software components to ensure they work together correctly.

• Purpose: Integration testing focuses on verifying the interfaces and interaction between modules or components of a software application. It aims to detect any discrepancies or faults in the way individual parts work together.

• Scope: Integration tests have a more focused scope compared to smoke tests, targeting specific interactions between components rather than the application as a whole. They delve into the details of how components communicate and function together.

• Frequency: Integration testing is performed after unit testing (where individual modules are tested in isolation) and before system testing (where the entire system is tested as a whole). It's conducted whenever new modules or changes that might affect interactions are introduced.

• Execution: These tests can be automated or manual, depending on the complexity of the interactions and the testing environment. They are more detailed and take longer to execute than smoke tests.

• Outcome: The aim is to identify and fix integration issues so that different parts of the application work seamlessly together. Successful integration testing ensures that software components operate correctly as a unit.

Unit Testing

Unit testing focuses on the smallest part of the code - checking the logic of individual functions.

• Purpose: The main goal of unit testing is to validate that each individual component or unit of the software works correctly on its own. It helps developers to identify bugs at an early stage in the development process.

• Scope: Unit tests are fine-grained and focused strictly on the functionality of specific units of code, such as functions, methods, or classes. They do not test interactions between components or the behavior of the application as a whole.

• Frequency: Unit tests are typically written and executed by developers as they write code, often following a Test-Driven Development (TDD) approach. They are run frequently during the development process to ensure that new changes do not break existing functionality.

• Execution: These tests are almost always automated, allowing them to be run quickly and frequently. Automation also facilitates regression testing, ensuring that previously tested units continue to operate correctly after code changes.

• Outcome: Successful unit tests confirm that individual units of code meet their design and behave as intended. When a unit test fails, it indicates a specific problem within the tested code unit, allowing developers to address issues early.

Comparison

• Level of Detail: Unit testing is the most granular form of testing, focusing on the smallest parts of an application. In contrast, smoke testing is a high-level check of basic functionality, and integration testing focuses on the interactions between software components.

• Purpose and Scope: Smoke tests are designed to quickly assess whether a software build is stable enough for further testing, covering critical functionalities without going into details. Integration tests examine how well different parts of the system work together, whereas unit tests ensure that individual components function correctly in isolation.

• Execution and Frequency: Unit tests are run very frequently during the development process, often automatically as part of a continuous integration pipeline. Smoke tests are also automated and performed on new builds, but their purpose is to serve as a preliminary check. Integration testing is done after unit testing but before system testing, targeting the connections and interactions between components.