It had been a long day, so a few of the fellows from the class agreed to meet a restaurant downtown. The main courses had been cleared off the table, some beer had been delivered, and we were waiting for dessert. Pedro (not his real name) was complaining, again, about how much time he had to spend doing administrivial tasks—meetings, filling out forms, time sheets, requisitions, and the like. “Everything … Read more
Over the last few years, people have become increasingly enthusiastic about the idea of mind mapping to help them describe or illustrate or otherwise consider test coverage. For me, Darren McMillan was the one who really got the ball rolling here, here, and here. More recently there have been other examples to present coverage ideas. Colleague Adam Goucher has weighed in here. But there’s another thing you can do, something … Read more
Several years ago, I wrote an article for Better Software Magazine called Testing Without a Map. The article was about identifying and applying oracles, and it listed several dimensions of consistency by which we might find or describe problems in the product. The original list came from James Bach. Testers often say that they recognize a problem when the product doesn’t “meet expectations”. But that seems empty to me; a … Read more
In the last post in this series, I noted some potentially useful structual similarities between bug reports (whether oral or written) and newspaper reports. This time, I’ll delve into that a little more. To our clients, investigative problem reports are usually the most important part of the product story. The most respected newspapers don’t earn their reputations by reprinting press releases; they earn their reputations through investigative journalism. As testers … Read more
We were in the middle of a testing exercise at the Amplifying Your Effectiveness conference in 2005. I was assisting James Bach in a workshop that he was leading on testing. He presented the group with a mysterious application written by James Lyndsay—an early version of one of the Black Box Test Machines. “How many test cases would you need to test this application?” he asked. Just then Jerry Weinberg … Read more
Calculating a ratio of passing tests to failing tests is a relatively easy task. If it is used as a means of estimating the state of a development project, though, the ratio is invalid, irrelevant, and misleading. At best, if everyone ignores it entirely, it’s simply playing with numbers. Otherwise, producing a pass/fail ratio is irresponsible, unethical, and unprofessional. A passing test is no guarantee that the product is working … Read more
Exploratory testing is not “after-everything-else-is-done” testing. Exploratory testing can (and does) take place at any stage of testing or development. Indeed, TDD (test-driven development) is a form of exploratory development. TDD happens in loops, in which the programmer develops a check, then develops the code to make the check pass (along with all of the previous checks), then fixes any problems that she has discovered, and then loops back to … Read more
In my recent blog post, Testing Problems Are Test Results, I noted a question that we might ask about people’s perceptions of testing itself: Does someone perceive testing to be difficult or time-consuming? Who? What’s the basis for that perception? What assumptions underlie it? The answer to that question may provide important clues to the way people think about testing, which in turn influences the cost and value of testing. … Read more
I often do an exercise in the Rapid Software Testing class in which I ask people to catalog things that, for them, make testing harder or slower. Their lists fit a pattern I hear over and over from testers (you can see an example of the pattern in this recent question on Stack Exchange). Typical points include: I’m a tester working alone with several programmers (or one of a handful … Read more
A while ago, James Bach and I did a transpection session. The object of the conversation was to think critically about the common trope that every test consists of at least an input and an expected result. We wanted to go deeper than that, and in the process we discovered a number of useful ideas. A test can be informed by an expectation, but oracles can also be developed on … Read more