Dynamic Testing Techniques

Dynamic Testing Techniques Software Testing ISEB Foundation Certificate Course 1 Principles 2 Lifecycle 4 Dynamic test techniques 3 Static testing 5 Management 6 Tools 1 Contents What is a testing technique? Black and White box testing Black box test techniques White box test techniques Error Guessing ISEB Foundation Certificate Course Dynamic Testing Techniques 1 2 3 4 5 6 2 Why dynamic test techniques? n Exhaustive testing (use of all possible inputs and conditions) is impractical must use a subset of all possible test casesmust use a subset of all possible test cases must have high probability of detecting faultsmust have high probability of detecting faults n Need thought processes that help us select test cases more intelligently test case design techniques are such thought test case design techniques are such thought processesprocesses 3 What is a testing technique? n a procedure for selecting or designing tests n based on a structural or functional model of the software n successful at finding faults n 'best' practice n a way of deriving good test cases n a way of objectively measuring a test effort Testing should be rigorous, thorough and systematic 4 Using techniques makes testing much more effective Advantages of techniques n Different people: similar probability find faults gain some independence of thoughtgain some independence of thought n Effective testing: find more faults focus attention on specific types of faultfocus attention on specific types of fault know you're testing the right thing know you're testing the right thing n Efficient testing: find faults with less effort avoid duplicationavoid duplication systematic techniques are measurablesystematic techniques are measurable 5 Measurement n Objective assessment of thoroughness of testing (with respect to use of each technique) useful for comparison of one test effort to anotheruseful for comparison of one test effort to another n E.g. Project A 60% Equivalence partitions 50% Boundaries 75% Branches Project B 40% Equivalence partitions 45% Boundaries 60% Branches 6 Contents What is a testing technique? Black and White box testing Black box test techniques White box test techniques Error Guessing ISEB Foundation Certificate Course Dynamic Testing Techniques 1 2 3 4 5 6 7 Three types of systematic technique Static (non-execution) •• examination of documentation,examination of documentation, source code listings, etc.source code listings, etc. Functional (Black Box) •• based on behaviour /based on behaviour / functionality of softwarefunctionality of software Structural (White Box) •• based on structurebased on structure of softwareof software 8 Some test techniques Static Dynamic Structural Behavioural FunctionalNon-functional ReviewsReviews WalkthroughsWalkthroughs Desk-checkingDesk-checking Data Flow Symbolic Execution Symbolic Execution Definition -Use Definition -Use StatementStatement Branch/DecisionBranch/Decision Branch ConditionBranch Condition Branch Condition Combination Branch Condition Combination LCSAJLCSAJ ArcsArcs Equivalence Partitioning Equivalence Partitioning Boundary Value Analysis Boundary Value Analysis Cause-Effect GraphingCause-Effect Graphing RandomRandom UsabilityUsability PerformancePerformance Static AnalysisStatic Analysis InspectionInspection Control Flow etc.etc. etc.etc. etc.etc. etc.etc. etc.etc. State TransitionState Transition 9 Black box versus white box? Integration Component Acceptance System Black box appropriate at all levels but dominates higher levels of testing White box used predominately at lower levels to compliment black box 10 [...]... Foundation Certificate Course Dynamic Testing Techniques Contents What is a testing technique? Black and White box testing Black box test techniques White box test techniques Error Guessing 11 Black Box test design and measurement techniques n n Techniques defined in BS 7925-2 - Equivalence partitioning Also a measurement - Boundary value analysis technique? = Yes - State transition testing = No - Cause-effect... relation to EP and BVA Input value Output value FALSE TRUE 34 State Transition Testing Not covered in this course Info available as supplement 35 1 2 3 4 5 6 ISEB Foundation Certificate Course Dynamic Testing Techniques Contents What is a testing technique? Black and White box testing Black box test techniques White box test techniques Error Guessing 36 ... in BS 7925-2 - Equivalence partitioning Also a measurement - Boundary value analysis technique? = Yes - State transition testing = No - Cause-effect graphing Cause- Syntax testing - Random testing Also defines how to specify other techniques 12 Equivalence partitioning (EP) - divide (partition) the inputs, outputs, etc into areas which are the same (equivalent) - assumption: if one value works, all... as well - technically correct and may be OK if everything works correctly! - if the test fails, is the whole partition wrong, or is a boundary in the wrong place - have to test midmidpartition anyway - testing only extremes may not give confidence for typical use scenarios (especially for users) - boundaries may be harder (more costly) to set up 21 Test objectives? Condition n n Valid Tag Invalid Tag . Dynamic Testing Techniques Software Testing ISEB Foundation Certificate Course 1 Principles 2 Lifecycle 4 Dynamic test techniques 3 Static testing 5 Management 6 Tools 1 Contents What is a testing. and White box testing Black box test techniques White box test techniques Error Guessing ISEB Foundation Certificate Course Dynamic Testing Techniques 1 2 3 4 5 6 2 Why dynamic test techniques? n. Boundaries 60 % Branches 6 Contents What is a testing technique? Black and White box testing Black box test techniques White box test techniques Error Guessing ISEB Foundation Certificate Course Dynamic