Page 259 - Software and Systems Requirements Engineering in Practice

ç ç 3 O F T W A R E ç ç 3 Y S T E M S ç 2 E Q U I R E M E N T S ç % N G I N E E R I N G ç ) N ç 0 R A C T I C E

2EQUIREMENTS %NGINEERING )NPUTS FOR 4ESTING
)N #HAPTER WE DISCUSSED THAT A hGOODv REQUIREMENT MUST BE VERIFIABLE
SUCH THAT THE FINISHED PRODUCT CAN BE TESTED TO ENSURE THAT IT MEETS THE
REQUIREMENT 4HIS MEANS THAT REQUIREMENTS MUST BE QUANTIFIABLE AND
EASILY TESTED )N ADDITION FOR AUTOMATED TEST GENERATION REQUIREMENTS
MUST BE DESCRIBED IN A FORM THAT CAN BE UNDERSTOOD BY COMPUTERS OR
SPECIALIZED TESTING EQUIPMENT OR THE REQUIREMENTS ENGINEERING ARTIFACTS
MUST BE EASILY TRANSLATED TO SUCH A FORM 4HIS IMPLIES THAT REQUIREMENTS
DESCRIBED AS MODELS WILL MAKE THE TESTER S JOB EASIER
7HEN TESTERS HAVE ACCESS TO REQUIREMENTS SPECIFICATIONS THAT ARE
VERIFIABLE COMPLETE UNAMBIGUOUS AND SO ON SEE 3ECTION THEY
WILL BE ABLE TO UNDERSTAND WHAT THE INTENDED SYSTEM SHOULD DO AND
HOW IT SHOULD PERFORM 7ITH A CLEAR UNDERSTANDING OF THE FUNCTIONALITY
AND PERFORMANCE OF THE INTENDED SYSTEM THEY SHOULD BE ABLE TO
WRITE hGOODv TEST CASES
)N ADDITION TO REQUIREMENTS OR SYSTEM SPECIFICATIONS OTHER
ARTIFACTS THAT ARE USEFUL TO TEST ENGINEERS INCLUDE USER MANUALS AND
PROTOTYPES SEE #HAPTER 3INCE MUCH OF THE SYSTEM TESTING TYPICALLY
IS DONE THROUGH A USER INTERFACE 2% AND DESIGN ARTIFACTS THAT
DESCRIBE THE OPERATION OF THE USER INTERFACE E G THE USER INTERFACE
DESIGN SPECIFICATION WILL BE USEFUL TO THE TESTER ;6IEIRA ET AL =
;3ONG ET AL = &OR AUTOMATICALLY GENERATING TEST CASES AND
EXECUTING THOSE TESTS ARTIFACTS THAT CONTAIN MODELS WILL BE HELPFUL
;(ASLING ET AL = ! SCENARIO WHERE IT IS POSSIBLE TO GENERATE
TEST CASES AUTOMATICALLY FROM A REQUIREMENTS SPECIFICATION IS
I REQUIREMENTS ENGINEERS CREATE MODELS DESCRIBING THE REQUIREMENTS
FOR THE SYSTEM UNDER TEST AND THEN II THE TESTING ENGINEERS USE THOSE
MODELS AS INPUTS TO A MODEL BASED TESTING TOOL WHICH CAN
AUTOMATICALLY PRODUCE A SET OF TESTS 4YPICALLY THOSE TESTS ARE hABSTRACTv
I E NOT READY FOR EXECUTION YET BUT THEY PROVIDE EARLY TEST
DOCUMENTATION AND A TEST PLAN THAT CAN GUIDE FUTURE TEST CREATION

-ODEL "ASED 4ESTING
-ODEL BASED TESTING ATTEMPTS TO DERIVE TEST CASES FROM A GIVEN MODEL
OF THE SYSTEM UNDER TEST 354 USING A VARIETY OF TEST SELECTION CRITERIA
! MODEL IS AN ABSTRACT VIEW OF THE SYSTEM AND SPECIFIES TYPICALLY
PARTS OF THE BEHAVIOR OF THE SYSTEM IN TERMS OF ITS CONTROL FLOW AND
OR DATA FLOW 4HREE DIFFERENT TYPES OF MODELS TYPICALLY CAN BE CREATED
v 2EQUIREMENTS MODELS THAT SPECIFY THE INTENDED BEHAVIOR OF THE
SYSTEM
v 5SAGE MODELS THAT REFLECT THE BEHAVIOR OF A POTENTIAL USER
v -ODELS CONSTRUCTED FROM THE SOURCE CODE DIRECTLY WHERE THE
SYSTEM UNDER TEST IS A SOFTWARE PRODUCT