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Showing posts from 2012

Simple test automation, with no moving parts.

This is an Ishihara Color Test. Its used to help diagnose colour blindness, people with certain forms of colour blindness would not be able to read the text contained in the image. The full set of 38 plates would allow a doctor to accurately diagnose the colour-perception deficiencies affecting a patient.

The test is ingenious in its concept, yet remarkably simple in its execution. No complicated lenses, lighting, tools or measuring devices are required. The doctor or nurse can quickly administer the test with a simple and portable pack of cards.

The Ishihara test is an end to end test. Anything, from lighting in the room, to the brain of the patient can influence the result. The examiner will endeavour minimise many of the controllable factors, such as switching off the disco lights, asking the patient to remove their blue tinted sun-glasses and maybe checking they can read normal cards (e.g. your patient might be a child.).

End to end tests like this are messy, many factors can be in-…

Cincinnati Test Store

Monday 3rd September 1827, A man steps off the road at the corner of Fifth and Elm, and walks into a store. He's frequented the store a few times since it opened, and he's starting to get to know the owner and his range of merchandise. In fact, like many of people in town he's becoming a regular customer.

He steps up to the counter, both he and the store owner glance at the large clock hanging on the wall and nod in unison. The shop-keeper makes a note of the time, the two then begin a rapid discussion of requirements and how the shop keeper might be able to help. When they've agreed what's needed, the shop keeper prepares the various items, bringing them to the counter, weighed, measured and packaged ready for transport to the customers nearby holding.

The store keeper then presents the bill to the customer, who glances at the clock again, and the prices listed on each of the items arranged around the store's shelves and then pays. The customer smiles as he loa…

Using test automation to help me test, a Google Elevation API example

Someone once asked me if "Testing a login-process was a good thing to 'automate'?". We discussed the actual testing and checking they were concerned with. Their real concern was that their product's 'login' feature was a fundamental requirement, if that was 'broken' they wanted the team to know quick and to get it fixed quicker. A failure to login was probably going to be a show-stopping defect in the product. Another hope was that they could 'liberate' the testers from testing this functionality laboriously in every build/release etc.

At this point the context becomes relevant, the answers can change depending the team, company and application involved. We have an idea of what the team are thinking - we need to think about why they have those ideas. For example, do we host or own the login/authentication service? if not, how much value is their in testing the actual login-process? Would a mock of that service suffice for our automated ch…

A simple test of time.

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 0130h might …

How to avoid testing in circles.

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 health…

Manual means using your hands (and your head)

I recently purchased a Samsung Galaxy Tab and an iPad2. Unlike many of my previous gadget purchases, these new gadgets have become very much part of the way I now work and play. One thing I like about them, is their tactile nature. You have a real sense that their is less barrier between you and what you want to do. If you want to do something - you touch it - and it 'just' does it. I don't have to look at a different device, click a couple of keys or move a box on a string to get access to what I can see right in front of me.

Features such as the haptic feedback provide a greater feeling that you are actually working with a tool, rather than herding unresponsive 'icons' or typing magic incantations into a typing device, originally conceived 300 years ago.

The underlying software systems used in these devices is a UNIX variant, just like the computer systems that underpin the majority of real world systems from the internet to a developer's shiny Apple Mac or L…

Nobody expects the...

In a previous post I discussed one method I use to improve my testing skills, spending spare minutes testing a machine or website that is readily at hand. The example I used was Google's search, in particular its currency conversion feature. This is useful for getting practice, and trying to speed up my testing, that is - finding information more quickly.

Another activity I perform is watching someone else test something. As testers, we are often asked to be a second pair of eyes, as its assumed that a programmer might not notice some issues in their own code. The idea being that you will not be blinded by the same assumptions, and will hopefully find new issues with the software. Using the same logic, by watching someone else test, I can examine their successes and failures more easily.

I've asked many people to test a variety of objects, usually things to hand, like a wristwatch or something I've recently bought. One recurring pattern I have noticed is how programmers an…