Types of Functional Testing
- Unit Testing
- Integration Testing
- System Testing
- End-to-end Testing
- Acceptance testing
- What is Unit Testing?
Unit Testing is a type of software testing where individual components or units of a program are tested in isolation to verify their correctness. The purpose is to ensure that each unit of the software functions as expected.
Key Points:
Focus: Test individual functions, methods, or classes within the application.
Purpose:
- Identify bugs or errors at an early stage in development.
- Ensure that each unit operates as intended in isolation..
Performed By: Typically done by developers, often using automated testing frameworks (e.g., JUnit, NUnit).
Types of Tests: Includes testing methods, functions, or individual pieces of code
Unit testing helps to catch issues early, making the software more maintainable and reliable.
- What is Integration Testing?
Integration Testing is a type of software testing where individual modules or components are combined and tested as a group to ensure they work together correctly.
Key Points:
Focus: Test data flow and interaction between modules.
Purpose: Identify defects in the integration points or interfaces between components.
Approach:
Big Bang Testing: All modules are integrated at once and tested as a whole.
Incremental Testing: Modules are tested incrementally using:
- Top-Down Approach: Testing starts from the top (higher-level modules) and progresses downward.
- Bottom-Up Approach: Testing starts from the lower-level modules and progresses upward.
- Hybrid/Sandwich Approach: Combines top-down and bottom-up approaches.
Integration testing ensures that the combined modules function as expected and work seamlessly together.
- What is System Testing?
System Testing is a type of software testing that evaluates the complete and integrated application as a whole to ensure it meets the specified requirements. It is conducted after integration testing and verifies the system’s overall behavior and functionality.
Key Points:
Focus: Test the entire system, including all modules and components, as a single entity.
Purpose: Ensure the system works end-to-end and meets business and technical requirements.
Types of Testing Included:
- Functional Testing
- Non-Functional Testing (e.g., performance, security, usability, and compatibility testing)
- Recovery Testing
- Installability Testing
System testing is typically performed in an environment that closely resembles the production environment to mimic real-world usage scenarios. It serves as the final validation before User Acceptance Testing (UAT).
- What is End-to-end Testing?
End-to-End (E2E) Testing is a type of software testing that involves testing an application as a whole, from start to finish, to ensure that all components and systems work together as expected. It simulates real-world user scenarios to validate the entire flow of the application, including integration with external systems and dependencies.
Key Points:
Focus: Validate the application’s complete functionality, including interactions between various components, databases, external services, and user interfaces.
Purpose:
- Ensure the entire system functions as intended in a real-world environment.
- Test all components together to check for integration issues.
- Verify that the software meets business requirements.
Performed By: Testers or QA teams, often using automated testing tools (e.g., Selenium, Cypress).
What Is Tested:
- User interactions and workflow.
- Integration with databases, APIs, and third-party services.
- Data flow between front-end and back-end systems.
E2E testing helps identify potential issues in the entire workflow, ensuring that the application functions seamlessly in a production-like environment.
- What is Acceptance testing(UAT)?
User Acceptance Testing (UAT) is the final phase of software testing where the end-users or clients validate whether the software meets their requirements and is ready for deployment. It focuses on verifying the software’s functionality, usability, and performance in real-world scenarios.
Key Points:
Focus: Ensure the system aligns with business needs and user expectations.
Performed By: End-users, clients, or stakeholders.
Purpose:
- Validate real-world usage.
- Ensure the system is ready for production.
- Identify any gaps between requirements and implementation.
Types of UAT:
- Alpha Testing: Conducted in a controlled environment by internal staff or selected users.
- Beta Testing: Performed by actual users in a real-world environment.
Successful UAT ensures the software is fit for use and meets all specified
