Test design techniques ( CHOOSING A TEST TECHNIQUE (Type of system,…
Test design techniques
IDENTIFYING TEST CONDITIONS AND DESIGNING TEST CASES
Formality of test documentation
Test analysis: identifying test conditions
the process of looking at something that can be used to derive test information
Test design: specifying test cases
Test implementation: specifying test procedures or scripts
CATEGORIES OF TEST DESIGN TECHNIQUES
Static testing techniques
Specification-based (black-box) testing techniques
Structure-based (white-box) testing techniques
Experience-based testing techniques
SPECIFICATION-BASED OR BLACK-BOX TECHNIQUES
Equivalence partitioning and boundary value analysis
Equivalence partitioning (EP) is a good all-round specification-based blackbox technique.
Boundary value analysis (BVA) is based on testing at the boundaries between partitions
Decision table testing
A decision table is a good way to deal with combinations of things
State transition testing
State transition testing is used where some aspect of the system can be described in what is called a 'finite state machine'.
Use case testing
Use case testing is a technique that helps us identify test cases that exercise the whole system on a transaction by transaction basis from start to finish
STRUCTURE-BASED OR WHITE-BOX TECHNIQUES
Using structure-based techniques to measure coverage and design tests
Structure-based test design techniques are a good way of generating additional test cases that are different from existing tests
Test coverage measures in some specific way the amount of testing performed by a set of tests
Types of coverage
EP: percentage of equivalence partitions exercised
BVA: percentage of boundaries exercised
Decision tables: percentage of business rules or decision table columns tested;
State transition testing
How to measure coverage
Decide on the structural element to be used, i.e. the coverage items to be counted
Count the structural elements or items.
Instrument the code.
Run the tests for which coverage measurement is required.
Using the output from the instrumentation, determine the percentage of elements or items exercised.
Statement coverage and statement testing
Decision coverage and decision testing
Other structure-based techniques
Linear code sequence and jump (LCSAJ) coverage
multiple condition coverage
Error guessing is a technique that should always be used as a complement to other more formal techniques
Exploratory testing is a hands-on approach in which testers are involved in minimum planning and maximum test execution.
CHOOSING A TEST TECHNIQUE
Tester knowledge I experience
Life cycle model
Customer I contractual requirements
Type of system
Time and budget