cs498dm Software Testing Darko Marinov January 27, 2009

Administrative Info Mailing list confirmed last time Wiki permissions should be set –People page: Thank you for signing up –11 students so far Any questions about the course overview? –Schedule (order set but dates are tentative) –Syllabus –Project: testing refactoring engines

Textbook “Introduction to Software Testing” by Paul Ammann and Jeff Offutt Reordered in the bookstore –The order from Fall was somehow missed –To call bookstore, searched for phone number –“Bug” in Google: search for “u of i bookstore” Results depend on location (feature not bug)

Previous Lectures Introduction to “Bugs” –Why look for bugs? What are bugs? –Where they come from? How to detect them? Example ambiguous informal statement: “everybody likes a winner”; meaning? 1.some w: Winner | some p: Person | p.likes(w) 2.some w: Winner | all p: Person | p.likes(w) 3.all p: Person | some w: Winner | p.likes(w) 4.all p: Person | all w: Winner | p.likes(w)

Today’s Lecture: Example Interactive Testing Session Test some small program –TriTyp: Given three integers for the lengths of the sides of a triangle, find the type of triangle –Show some example in Eclipse Several reasons to do this together –We will learn some testing terminology –It should be fun to look for some bugs –We can learn from mistakes as we go

Testing Levels Based on Software Activity Unit testing (Module testing) Integration testing System testing (Acceptance testing) Regression testing Names are not standardized –I don’t insist on names; we will follow the book

Test Cases Test case values (inputs) Expected results (if known) Prefix values Postfix values –Verification values –Exit commands Test set/suite: a set of test cases

Some Other Terminology Black-box testing White-box testing (or glass-box, clear-box) Top-down testing Bottom-up testing Static testing Dynamic testing

Coverage Criteria Did we have any test plan or purpose? Did we specify any test requirements? How good are our tests? Did we generate enough tests? Criterion: rule that imposes test requirements Coverage: satisfaction of test requirements

Automated Testing We want to test (early and often) –Automated testing –Regression testing Can use JUnit (or a similar tool) Alternatives have some cons –Different language for scripting –A lot of printing if no checking of result –Using “main” does not compose well

Next Lecture Thursday, January 29: Refactoring –What is it? Why you need it? How to perform it? –Guest lecture by a student expert on refactoring After that, lab on testing and then start more on coverage criteria “Assignments”: –Sign up at People page on Wiki if you didn’t –Try Java, JUnit, Eclipse ( TA and me if completely unfamiliar)