TEST CASE DESIGN

1
TEST CASE DESIGN

• Prepared by Fatih Kizkun

2
OUTLINE

• Introduction
• Importance of Test
• Essential Test Case Development
• A Variety of Test Methods
• Risk Based Testing
• Use Case/UML
• Finite State Model Based Technique
• Conclusion

3
INTRODUCTION(1)

• Failure A program behaves differently as
  required by the specification.
• Error The internal state of a program is invalid
  (e.g. a precondition, post condition, undefined
  pointers etc).
• Fault A static cause which allows errors to
  occur (e.g. bugs, design faults, hardware or
  system faults).

4
INTRODUCTION(2)

• Faults are
• static and can lead to error states.
• observed by Black Box Test
• Tests
• try to detect failures.
• observe error states that are tracked down to
  faults

5
INTRODUCTION(3)Types of Tests

• Tests of units (classes, individual methods,
  modules and procedures)
• Test units concurrently
• Locating faults easier
• Higher-Order Testing (test of the whole program)
• Detect errors because of inconsistency

6
INTRODUCTION(4)Performing a Good Test

• Know the Characteristics of a Good Test
• Know what an Equivalence Class is
• Finding Equivalence Class
• Select Test Cases from Each Equivalence Class
• Test State Transitions
• Test Time Dependencies
• Test Load Limitations
• Guess
• Test Function Equivalence
• Automate Function Equivalence Testing
• General Equivalence Testing
• Regression Testing
• Executing the Tests

7
A Variety of Test Methods
8
TEST METHODS

• Risk-based testing
• Requirements-based Testing
• Use Case/UML
• Keyword or Action Based Test (ABT) methodology
• State Transition/ State Model Based Testing
• Exploratory and Effective Ad Hoc Testing
• Equivalence Class Partitioning and Boundary Value
  Analysis
• Regression testing
• Fault Injection/ Forced Error/ Negative Testing
• DAST- Diagnostic Approach to Software Testing
• Data Driven Testing

9

• RISK BASED TESTING

10
RISK BASED TESTING(1)

• Make a prioritized list of risks
• Perform testing that explores each risk
• As risks evaporate and new ones emerge, adjust
  your test effort to stay focused on the current
  crop

11
RISK BASED TESTING(2)INSIDE-OUT

• Begin with details
• identify risks associated with them.
• 3 questions to be asked
• Vulnerabilities What weaknesses or possible
  failures are there in this component?
• Threats What inputs or situations could there be
  that might exploit a vulnerability and trigger a
  failure in this component?
• Victims Who or what would be impacted by
  potential failures and how bad would that be?

12
RISK BASED TESTING(3)OUTSIDE-IN

• Begin with a set of potential risks
• Match potential risks to the details of the
  situation
• A more general approach than inside-out
• It