Testing in Agile Projects: Where Things Stand Today Brian Marick [email protected] Copyright © 02004 by Brian Marick. Permission granted to reproduce verbatim. Some images copyright www.arttoday.com. What Are Agile Projects? • An attitude toward change • An attitude toward software • Some attitudes toward people The Manifesto for Agile Software Development, www.agilemanifesto.org Changing Requirements Are Swell Oh! Let’s add this! Now that I see my feature, I don’t like it. Sure! How should we change it? Software Can Be Soft • Programs can become better, cleaner, and more capable • They become changeable by being successfully changed – not mainly by planning for change • Frequent new requirements “train” the code and the coders “Agile methods, the Emersonian worldview, and the dance of agency” www.visibleworkings.com/papers/agile-methods-and-emerson.html People • Written documentation is a poor substitute for continuous conversation • Generalists trump specialists • Teams can self-organize • Trust – “… if you ask for help, someone has to help you” - Lisa Crispin Agile Methodologies • • • • Extreme Programming Scrum DSDM Evolutionary delivery and staged delivery share many characteristics See “Reading” slides at the end The Import These attitudes toward change, software, and people are the context for testing in Agile projects Kaner, Bach, and Pettichord, Lessons Learned in Software Testing www.context-driven-testing.com/wiki/scribble.cgi Four Types of Testing Geoffrey Moore, Crossing the Chasm, p. 19 Programmer Testing I need an object that records each time segment Test-driven design Unit testing Programmer Testing The test comes first Programmer Testing Code is written to pass the test Programmer Testing Not done? Write another test… Programmer Testing And the code to pass it. All earlier tests continue to pass Programmer Testing Code awkward? Fix it now. Tests continue to pass (Refactoring) Martin Fowler, Refactoring Programmer Testing Eventually, the jelly is cooked, nailed down, and ready for further change Status I need an object that records each time segment Why was this decision made? Because of a Customer Representative …I want to scribble notes about what I’m doing… FIT Tests Reminder, not requirement Makes sense to the customer representative Easy to run fit.c2.com Test Results BrowserFriendly Tests First Tests Make Change Smooth Has anything broken? Has anything broken? Has anything broken? small change small change small change Tests Inform Programmers • There are no explicit requirements or specifications – so tests cannot check code against them • Tests serve same goal as requirements or specifications – they provoke programmers to write the right program No way! Requirements for Test Notation • Provoking the right code • Improving product conversation – tests are something to talk about – ground conversation in the concrete – forging a common vocabulary • Making possibilities more noticeable – explaining to someone else supplements trying out working software – concreteness sparks ideas The Tester As Participant How can we best be concrete? What “goes without saying”? What should the product not do? Who’s being overlooked? What bugs seem likely? “Tester” As Job Title How can we best be concrete? What “goes without saying”? What should the product not do? Who’s being overlooked? What bugs seem likely? Status acceptance tests, customer tests, whole-product tests, business-facing tests… Mid-Course Observation Business Facing These tests primarily support programming (as well as the whole team’s understanding) Technology Facing Is This Really Testing? • Checked examples – for discussion – for confident implementation – where are the bugs? • Change detectors – for confident implementation – where are the bugs? What About When the Examples Are Bad Examples? (incomplete, misleading) Extending the Model Support Programming Business Facing Examples that use business terminology Examples that use interior terminology Technology Facing Extending the Model Examples that use business terminology ? Examples that use interior terminology ? Technology Facing Critique Product Support Programming Business Facing Critiquing the Product • What resource do we newly have? – the working product, including new code • Exploratory testing – “simultaneous learning, test design, and test execution” - James Bach • Doing what? – diverse users and their scenarios – imaginative end-to-end testing – some opportunistic feature testing www.satisfice.com/articles.shtml Exploratory Bug Finding Business Facing Examples that use business terminology User-centered bug reports Examples that use interior terminology ? Technology Facing Critique Product Support Programming A Quadrant Entry Status Still Not Addressed • What about security bugs, configuration bugs, performance problems, bugs revealed under load, usability problems (like suitability for color-blind people), etc. etc. etc.? – difficult to specify by example – whole-product, but not central to domain These Are Technology Issues Business Facing Examples that use business terminology User-centered bug reports Examples that use interior terminology ? Technology Facing Critique Product Support Programming • Understanding of implementation more important than understanding of a particular domain The Good News Business Facing Examples that use business terminology User-centered bug reports Examples that use interior terminology “ility” bug reports Technology Facing Critique Product Support Programming My Take on the State of the Practice Summary: Testing in Agile Projects Reading (1) • Agile development in general – www.agilealliance.org – Agile Software Development, Alistair Cockburn – “Agile methods, the Emersonian worldview, and the dance of agency”, Brian Marick, www.visibleworkings.com/papers/agile-methods-and-emerson.html • Extreme Programming – Extreme Programming Explained, Kent Beck – www.xprogramming.com/xpmag/whatisxp.htm • Scrum – Agile Software Development with Scrum, Schwaber and Beedle – www.mountaingoatsoftware.com/scrum • DSDM – DSDM: Business Focused Development, DSDM Consortium – www.dsdm.org Reading (2) • Agile from a tester’s point of view – – – – www.testing.com/agile Testing eXtreme Programming, Lisa Crispin and Tip House [email protected] www.testing.com/cgi-bin/blog • Programmer testing – – – – Test-Driven Design by Example, Kent Beck Test-Driven Development: A Practical Guide, Dave Astels Pragmatic Unit Testing, Hunt and Thomas [email protected] Reading (3) • Exploratory testing – www.satisfice.com/articles.shtml – www.testingcraft.com/exploratory.html • Context-driven testing – Lessons Learned in Software Testing, Kaner, Bach, and Pettichord – www.context-driven-testing.com/wiki/scribble.cgi • Miscellaneous – FIT: fit.c2.com (see also fitnesse.org) – Crossing the Chasm, Geoffrey Moore – Refactoring, Martin Fowler (et. al.)