F6

Question 1

• Structural testing (white-box, glass-box)

Answer 1

– Usescode/detaileddesignto develop test cases
– Typicallyusedinunittesting
– Approaches:
• Coverage-based testing • Symbolic execution
• Data flow analysis
• …

Question 2

• Functional testing (black-box)

Answer 2

– Usesfunctionspecificationsto develop test cases
– Typicallyusedinsystemtesting
– Approaches:
• Equivalence partitioning • Border case analysis
• …

Question 3

BLACK-BOX TESTING

Answer 3

Testgenerationwithoutknowledgeof software structure
• Alsocalledspecification-basedor functional testing
Equivalence partitioning Boundary-value analysis Error Guessing

Question 4

EQUIVALENCE PARTITIONING

Answer 4

Input- and output data can be grouped into classes where all members in the class behave in a comparable way.

Question 5

WHITE-BOX TESTING

Answer 5

Methods based on internal structure of code
Approaches:
– Coverage-based testing
• Statement coverage • Branch coverage
• Path coverage
• Data-flow coverage
– Symbolic execution – Data flow analysis

Question 6

COVERAGE-BASED TESTING adtavtages

Answer 6

– Systematic way to develop test cases – Measurable results (the coverage)
– Extensive tool support • Flow graph generators • Test data generators
• Bookkeeping
• Documentation support

Question 7

COVERAGE-BASED TESTING adtavtages dis

Answer 7

Disadvantages
– Code must be available
– Does not (yet) work well for data-driven programs

Question 8

PRE-IMPLEMENTATION TESTING

Answer 8

• Inspections
21
– evaluation of documents and code prior to technical review or testing
• Walkthrough – In teams
– Examine source code/detailed design
• Reviews
– More informal
– Often done by document owners

Question 9

PRE-IMPLEMENTATION TESTING advantages

Answer 9

Effective
– High learning effect
– Distributing system knowledge

Question 10

PRE-IMPLEMENTATION TESTING Disadvantages

Answer 10

o Expensive

Question 11

UNIT TESTING

Answer 11

Tests the smallest individually executable code units.
Objective: Find faults in the units. Assure correct functional behavior of units.
By: Usually programmers. Tools:
• Testdriver/harness
• Coverageevaluator
• Automatictestgenerat

Question 12

INTEGRATION TESTING

Answer 12

• Testing two or more units or components
• Objectives
– Interfaceerrors
– Functionality of combined units;look for problems with functional threads
• By: Developers or Testing group
• Tools:Interface analysis;callpairs
• Issues:Strategy for combining units

Question 13

INTEGRATION TESTING

How to integrate & test the system

Answer 13

• Top-down
• Bottom-up
• Criticalunitsfirst  
• Functionality-oriented(threads)
Implications of build order
• Top-down=>stubs;morethoroughtop-level
• Bottom-up=>drivers;morethoroughbottom-
level
• Critical=>stubs&drivers.

Question 14

SYSTEM TESTING

Answer 14

Testthefunctionality,performance, reliability, security of the entire system.
• By:Separatetestgroup.
• Objective:Finderrorsintheoverall system behavior. Establish confidence in system functionality. Validate that system achieves its desired non- functional attributes.
• Tools:Usersimulator.Loadsimulator

Question 15

ACCEPTANCE TESTING

Answer 15

• Operatesysteminuserenvironment, with standard user input scenarios.
• By:Enduser
• Objective:Evaluatewhethersystem meets customer criteria. Determine if customer will accept system.
• Tools:Usersimulator.Customertest scripts/logs from operation of previous system.

Question 16

REGRESSION TESTING

Answer 16

• Defn:Testofmodifiedversionsof previously validated system.
• By:Systemorregressiontestgroup.
• Objective:Assurethatchangesto system have not introduced new errors.
• Tools:Regressiontestbase, capture/replay
• Issues:Minimalregressionsuite,test prioritization

Question 17

THE KEY PROBLEMS OF SOFTWARE TESTING

Answer 17

Selecting or generating the right test cases. Knowing when a system has been tested enough.
Knowing what has been discovered/ demonstrated by execution of a test suite.

Question 18

REALITIES OF SYSTEM TESTING

Answer 18

• Availabletimefortestingisshort
– Compressing development risks introducing problems – Compressing testing risks missing critical problems
• Testerswanttostarttestingearly
• Systemtestingrequiresanavailablesystem
• Developersresisttestinguntilsystemis“ready”
To optimize use of the existing resources, use risk analysis.