Software Testing Verification and Validation：软件测试验证和确认

1、wednesday, may 05, 2021ch.19 - verification reliability) statistical testing ch.21 automated dynamic analysis (if applicable) wednesday, may 05, 2021ch.19 - verification & validation5 verification and validation goals establish that software is fit for purpose, not “bug-free” “good enough” depends o

2、n: software function (critical nature?) user expectations market competition, price wednesday, may 05, 2021ch.19 - verification & validation6 testing vs. debugging verification and validation looking and categorizing existence of system defects example bug list “what?” debugging locating and correct

3、ing these defects “why?” wednesday, may 05, 2021ch.19 - verification & validation7 canned test runs to verify that new defects were not introduced during “debugging” session. not exhaustive targeted to a particular interface components, sub-systems, integrated system different levels (lengths) of re

4、gression tests targeted regressions regression testing wednesday, may 05, 2021ch.19 - verification & validation8 planning should begin right after requirements specification acceptance tests can be written then system, sub-system tests can be written against designs the test plan wednesday, may 05,

5、2021ch.19 - verification & validation9 the test plan wednesday, may 05, 2021ch.19 - verification & validation10 software inspections (code reviews) 60% of program errors can be detected in code review fagan86 90% if more formal approach used (e.g. “cleanroom” process) mills87 (well talk about cleanr

6、oom later) wednesday, may 05, 2021ch.19 - verification & validation11 software inspections (code reviews) why are reviews more effective for finding defects in systems/subsystems (i.e., before acceptance testing)? bugs are often masked by other bugs leverage domain/programming knowledge inspectors a

7、re skilled programmers common practice: code reviews and then acceptance testing reviews can also help with development of tests wednesday, may 05, 2021ch.19 - verification & validation12 software inspections (code reviews) sample procedure: announce review meeting in advance (a week?) provide desig

8、n document, implementation overview, and pointer to code reviewers read code (and make notes) in advance of meeting during meeting, directives recorded by scribe testers/documenters attend too wednesday, may 05, 2021ch.19 - verification & validation13 automated static analysis case tools that catch program curiosities that are usually indicative of bugs: unreachable code uninitialized variables unreferenced variables programming language dependent e.g., lint (for c) wednesday, may 05, 2021ch.19 - verification & validation14 automated dynamic analysis tools which do bookkeeping w