The Software Development Life Cycle - Testing

What is the testing phase? (Phase)

The testing phase is concerned with ensuring that the current software version conforms to the requirements defined in the software planning and/or design document by (how) rectifying defects and validating fixes 1.

The following activities are carried out in the testing phase [1, 2 c4]

• Planning
• Test environment development
• Test readiness review
• Test-case generation
• Execution
• Test logging and/or test results reporting
• Test results evaluation
• Program refinement
• Software handover to support staff

Why do I have to test software? (High-quality software)

[2 c4]

• Detect as many faults, and failures prior to software usage
• Improve software reliability by pre-emptively identifying and resolving faults, and failures
• Prove that a software project’s functionality, efficiency, and quality objectives have been met

Where do I test software? (Controlled environment)

• Locations: In person, remote, hybrid meetings, events, collaborations, interviews
• Persons: Quality assurance team, software testers, users
• Testing environment

When do I test software? (Design and development session)

• After development phase i.e. when an individual, business, or government having created a working software version/prototype want to prove the software satisfies the defined requirements
• During any phase in the SDLC project i.e. when a want or need is identified to alter any activity, result, report created in the testing phase

How do I test software? (Methodology)

[2 c4]

• Software testing principles
  • Dynamic: Test execution on select input (state)
  • Finite: Test execution on a subset of all possible tests
  • Selected: Select test input according to desired test result
  • Expected: Test must have a definite outcome
• Software testing methodologies:
  • Attitudes / Egoless Programming
  • Test guides
  • Test process management
  • Test documentation and work products
  • Test-Driven development
  • Internal vs. Independent test team
  • Cost/Effort estimation and test process measures
  • Termination
  • Test reuse and test patterns
• Software testing categories:
  • The target/object of the test
    • Unit testing: testing a single module
    • Integration testing: testing a group of related modules
    • System testing: testing an entire software system
  • The objective/purpose of the test
    • Acceptance/Qualification testing
    • Installation testing
    • Alpha and Beta testing
    • Operational (or Statistical) testing
    • Regression testing
    • Performance testing
    • Security testing
    • Stress testing
    • Back-to-Back testing
    • Recovery testing
    • Configuration testing
    • Interface testing
    • Usability testing
    • Human Computer Interface testing
  • Defect testing failed scenarios
    • Path testing
    • Data set testing
    • Black-box testing
    • White-box testing
    • Automation testing
• Software testing technologies:
  • Evaluation of the Program Under Test
  • Evaluation of the Tests Performed
• Software testing tools:
  • Test harnesses (drivers, stubs)
  • Test generators
  • Capture/replay tools
  • Oracle/file comparators/assertion checking tools
  • Coverage analyzers and instrumenters
  • Tracers
  • Regression testing tools
  • Reliability evaluation tools
• Software testing techniques:
  • Based on the Software engineer’s intuition and experience
  • Input Domain-Based techniques
  • Code-Based techniques
  • Fault-Based techniques
  • Usage-Based techniques
  • Model-Based testing techniques
  • Techniques based on the nature of the application
  • Selecting and combining techniques
• Software testing process:
  • Planning
  • Test environment development
  • Test readiness review
  • Test-case generation
  • Execution
  • Test logging and/or test results reporting
  • Test results evaluation
  • Program refinement
  • Software handover to support staff
• Project management process:
  • In a sequential methodology such as Waterfall, testing phase is a one-off activity
  • In an iterative methodology such as Agile, Prototype, development phase is a testing process
  • In an hybrid methodology, development phase is both a sequential and a concurrent phase
• Persons: Stakeholders, software engineers/developers who are directly involved with the project

On giant’s shoulders (References):

• 1. Systems development life cycle
• 2. Guide to the Software Engineering Body of Knowledge (SWEBOK) V3.0, IEEE Computer Society