软件测试与质量保证 Testing (4)学习课件

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SoftwareTestingTechniques(4)INSTRUCTOR:SHULIUHITSCHOOLOFSOFTWARE2017Allrightsreserved1SQAandTestingSoftwareTestingTechniquesBlack-BoxTestingWhite-BoxTestingDD-PathStatementCoverageTestingDD-PathTestingLoopCoverageTestingBasisPathTestingBottom-upTestingTop-downTestingSandwichTestingExamples:TheTriangleProblemTheNextDateFunctionTheCommissionProblemGray-BoxTestingSoftwareTestingTechniques2SQAandTestingTypicalModule

InterconnectionDiagramSoftwareTestingTechniquesabcdefghijklm3SQAandTestingBottom-UporTop-DownTestingLogicmodulesessentiallyincorporatethedecisionmakingflowofcontrolaspectsoftheproduct.Thelogicmodulesgenerallyarethosesituatedclosetotherootinthemoduleinterconnectiondiagram.Operationalmodules,ontheotherhand,performtheactualoperationsoftheproduct.SoftwareTestingTechniques4SQAandTestingTypicalModule

InterconnectionDiagramSoftwareTestingTechniquesabcdefghijklm5SQAandTestingLogicModule&OperationalModuleSoftwareTestingTechniquesabcdefghijklm6SQAandTestingTop-DownTestingTop-Downtestingisawhite-boxtestingtechnique.Thetop-downtestingisanincrementalapproachinwhichthehigh-levelmodulesorsystemcomponentsareintegratedandtestedfirst.Thenproceedshierarchicallytothebottomlevel.SoftwareTestingTechniques7SQAandTestingTop-DownTestingTop-Downtestingrequiresthecreationofstubs.Astub,anemptymodule,isapieceofthrow-awaycodethatemulateacalledunit.Amoreeffectivestubprintsamessagesuchas“moduledisplayColorPatterncalled”.Bestofall,astubshouldreturnvaluescorrespondingtopreplannedtestcases.SoftwareTestingTechniques8SQAandTestingTop-DownTestingWhenamoduleorsystemcomponentistested,themodulesorcomponentsitinvokesarerepresentedbystubs,whichreturncontrolbacktothecallingmoduleorsystemcomponentwithasimulatedresult.Astestingprogressesdowntheprogramstructure,eachstubisreplacedbytheactualcodeitrepresentsSoftwareTestingTechniques9SQAandTestingTop-DownTestingSoftwareTestingTechniquesabcdefghijklm10SQAandTestingTop-DownTestingSoftwareTestingTechniquesabcdefghijklm11SQAandTestingTop-DownTestingSoftwareTestingTechniquesabcdefghijklm12SQAandTestingTop-DownTestingSoftwareTestingTechniquesabcdefghijklm13SQAandTestingBottom-UpTestingBottom-uptestingisawhite-boxtestingtechnique.Thebottom-uptestingtechniqueisanincrementaltestingapproachwherethelowest-levelmodulesorsystemcomponentsareintegratedandtestedfirst.Testingthenproceedshierarchicallytothetoplevel.Adriver,ortemporarytestprogramthatinvokesthetestmoduleorsystemcomponent,isoftenrequired.SoftwareTestingTechniques14SQAandTestingBottom-UpTestingAdriver,amodulethatcallsthecurrenttestedmoduleoneormoretimes,ifpossiblecheckingthevaluesreturnedbythemoduleundertest.Bottom-uptestingstartswiththelowest-levelmodules(operationalmodule)withthedriverstoinvokethem,thennextlogicallevelintheprogramhierarchyisaddedandtesteddrivingupward.SoftwareTestingTechniques15SQAandTestingSoftwareTestingTechniquesabcdefghijklmBottom-UpTesting16SQAandTestingSoftwareTestingTechniquesabcdefghijklmBottom-UpTesting17SQAandTestingSoftwareTestingTechniquesabcdefghijklmBottom-UpTesting18SQAandTestingBottom-UpTestingBottom-upintegrationisa“mirrorimage”tothetop-downorder,withthedifferencethatstubsarereplacedbydrivermodulesthatemulateunitsatthenextlevelupinthetree.SoftwareTestingTechniques19SQAandTestingTop-Downvs.Bottom-UpAdvantagesforTop-Down:Top-downtestingallowsearlydiscoveryofmajordesignflawsoccurringatthetopoftheprogram.Stubsneedtobecreatedbutaregenerallyeasiertocreatedthandrivers.AdvantageforBottom-Up:Theoperationalmodulesarethoroughlytested,andiscommonusedforlarge,complexsystems.

SoftwareTestingTechniques20SQAandTestingTop-Downvs.Bottom-UpDisadvantagesforTop-Down:Criticallow-levelmodulesorsystemcomponentsarenottestedasfrequentlyastheupper-levelmodules.Potentiallyreusablemodulesmaynotbeadequatelytested.SoftwareTestingTechniques21SQAandTestingTop-Downvs.Bottom-UpDisadvantageforBottom-Up:Ittakesarelativelylongtimetomakethesystemvisibletouser.Majordesignfaultswillbedetectedlate,becausethelogicmodulesaretestedlast.Itrequiresalotofefforttocreatedrivers,whichcanaddadditionalerrors.

SoftwareTestingTechniques22SQAandTestingSandwichTestingSandwichtestingisawhite-boxtestingtechnique.Sandwichtestingusestop-downandbottom-uptechniquessimultaneously.Theapproachteststhesystemfromthetopandbottomatthesametime,meetingsomewhereinthemiddleofthehierarchicalcontrolstructure.SoftwareTestingTechniques23SQAandTestingSandwichTestingThelogicmodulesshouldbeintegratedandtestedtop-down.Theoperationalmodulesshouldbeintegratedandtestedbottom-up.Thentheinterfa