investigating software

Last week I was performing another of my 5 minute testing exercises. As posted before, if I get a spare few minutes I pick something and investigate. This time, I'd picked Google Calendar. One thing people use calendars for is logging what they have done. That is, they function as both schedulers and record keepers. You add what you planned to do, and they also serve as a record of what you did - useful for invoicing clients or just reviewing how you used your time. Calendars and software based on them are inherently difficult to program and as such are often a rich source of bugs. People make a lot of assumptions about time and dates. For example that something ends after it starts. That may sound like something that 'just is true', but there are a number of reasons why that might not be the case. Some examples are: You type in the dates the wrong way round (or mix up your ISO and US dates etc) You're working with times around a DST switch, when 30min after 0...

I once had an interesting conversation with a colleague who worked in a company selling hotel room bookings. The problem was interesting. Their profits depended on many factors. Firstly, fluctuating demand e.g.: Holidays, Weekends, Local events etc. Secondly, varying types of demand e.g. Business customers, Tourists, Single night bookings or e.g.: 11 day holidays. They also had multiple types of contracts on the rooms. For some, they might have had the exclusive right to sell [as they had pre-paid], for others they had an option to sell [at a lower profit] etc. My naive view had been they priced the room bookings at a suitable mark up, upping that markup for known busy times etc. For example a tourist hotel hotel near the Olympics would be a high mark up, the tourist hotel room in winter would have incurred less of a markup. Better to get some money than none at all). He smiled and said some places do that, but he didn't. He had realised his team had a bias towards making a hea...

In my last post I discussed how test automation could be used to do things that I couldn't easily do unaided. In that example, execute thousands of news 'content searches' and help me sort through them. With the help of some simple test automation I found some potential issues with the results returned by the REST API. In that case, I started out with the aim of implementing a tool. But your testing might not lead you that way, often your own hands-on investigation can find an issue. But you don't know how widespread it is, is it a one-off curiosity? or a sign of something more widespread.? Again, this is where test automation can help, and if done well, without being an implementation or maintenance burden. Many test automation efforts are blind to the very Agile idea of YAGNI or You Ain't Gonna Need it . They often presume to know all that needs to be tested in advance, deciding to invest most of their time writing 'tests' blindly against a specific...

Consistency, is one thing I test for in software. For example, if software refers to something by a particular name, then [usually] it should always refer to it by that name. Furthermore, when it uses that name e.g. 'London Tube Map' I would expect to see such a map, when I click to view it, and not another kind of map e.g.: a street map. Conventions, These are also an important part of software. People will [usually] expect your software to use conventions that are appropriate for the field. For example, The traditional London Tube map is a schematic diagram, designed to show the relative positions of the stations rather than their geographic location. Though, sometimes it's actually useful to have geographic information, e.g.: is Queensway (Central line) station very close to Bayswater (Circle line)? So if a map isn't using the schematic form, then the geographic form also has it uses. I would be surprised if I received a London Tube map that was neither schemati...