Thursday 6 November 2014

Visual Test Ideas

There are some circumstances in which a mind map is not the best format to visualise your testing. In particular, where there are complex relationships between data in the application under test.

Visual test ideas can be useful when it feels clumsy to explain what you plan to test in words. If you need the assistance of a whiteboard to outline your thinking to others, this might indicate that you should record your test ideas pictorially instead of in writing.

As with other visual approaches, visual test ideas are a great way to engage people in the activities of testing and encourage collaboration that improves test coverage.

Here are three examples of different ways to record your test ideas visually.

Timelines

Imagine the Transaction History for a bank account. When you load the page, you see the last 30 days of transactions by default. You can change the date range for transactions returned by updating the start and end dates:



Transactions are only returned for the first 90 days of the specified range. If the specified date range is greater than 90 days then the oldest transactions are discarded. Data is only available up to 180 days ago, no transaction information will return prior to that date. And of course, there are no transactions available in the future.

Given these requirements, a number of different test ideas spring to mind. As these ideas are discussed with other people, they might be captured in a timeline format:


Using a timeline to explain these test ideas clearly shows how they relate to one another within the time relationship, where a mind map format would not.

Buckets

Imagine that you have taken out a loan where your repayment obligations are tied to your income. When your earn beyond specific thresholds, then your repayment amount will change. These thresholds are dependent on the type of earning you receive, whether salary, wages or adjusted income.

The example below is from Aaron Hodder. Using a buckets marked with different thresholds, Aaron clearly shows how his test ideas relate to one another:



Venn Diagrams

Imagine a school grading system. Within a given subject, you can receive credits across one or many topics. For example, in Mathematics you can gain credits that apply to Calculus, Algebra, or Calculus & Algebra combined. The number of credits you have in each topic, and in total, will determine whether you are awarded a given qualification for a subject.

Nigel Charman has written about a team operating in this domain:

"In this case, the team are visualising examples of these complex business rules using Venn diagrams. The richness of the visualisation helps us wrap our brains around the complexity, acting as a shorthand form for discussion." [1]

An accompanying picture shows a team working around a whiteboard that is filled with various Venn diagrams:

Source: Visual Specification by Example
Instead of then attempting to reflect these scenarios in words, these same diagrams become the documented test ideas:

Source: Visual Specification by Example

Using Venn diagrams to capture these test ideas clearly shows the relationships between topics within subjects that a mind map format would not.

*****

There are many options for representing test ideas and the relationships between them by making use of engaging illustrations. Think laterally. Though a mind map is an obvious option to present visual information, it isn't always the best way for a tester to share their thoughts with their team.

1 comment:

  1. We use timelines a lot. I have also found flow charts to be quite useful. Firstly it makes sure everyone understands the requirement (often it does not occur to BA or Dev to draw one), secondly you can highlight each flow line to ensure decision coverage. Am now thinking several uses for the bucket and Venn diagrams thanks!

    ReplyDelete