A different model

Let’s step back for a second. What is our job?

There are times when some person or group of people hands some code to other peopleand says, “Hope you like it.” That happens when the whole project puts bits on a CD andgives them to customers. It also happens within a project:·

• One development team says to other teams, “We’ve finished the XML enhancementsto the COMM library. The source is now in the master repository; the executablelibrary is now in the build environment. The XARG team should now be unblocked –go for it!”·
• One programmer checks in a bug fix and sends out email saying, “I fixed the bug inallocAttList. Sorry about that.” The other programmers who earlier stumbled overthat code can now proceed.

In all cases, we have people handing code to other people, possibly causing themdamage. Testers intervene in this process. Before the handoff, testers execute the code,find bugs (the damage), and ask the question, “Do you really want to hand this off?” Inresponse, the handoff may be deferred until bugs are fixed.

This act is fundamental to testing, regardless of the other things you may do. If you don’texecute the code to uncover possible damage, you’re not a tester.Our test models should be built around the essential fact of our lives: code handoffs.Therefore, a test model should force a testing reaction to every code handoff in theproject. I’ll use the XML-enhanced COMM library as an example. That’s a handoff from oneteam to the rest of the project. Who could be damaged?

• It might immediately damage the XARG team, who will be using those XMLenhancements in their code.
• It might later damage the marketing people, who will be giving a demonstration ofthe “partner release” version of the product at a trade show. XML support is animportant part of their sales pitch.
• Still later, it might damage a partner who adopts our product.

We immediately have some interesting test planning questions. The simple thing to do would be to test the XML enhancements completely at the time of handoff. (By “completely,” I mean “design as many tests for them as you ever will.”) But maybe some XML features aren’t required by the XARG team, so it makes sense to test them through
the integrated partner release system. That means moving some of the XML-inspired testing to a later handoff. Or we might move it later for less satisfying reasons, such as that other testing tasks must take precedence in the near term. The XARG team will have to resign itself to stumbling over XML bugs for a while.

Our testing plan might be represented by a testing schedule that annotates the
development timeline.