Authors
Louise Pryor
Abstract
Testing is a vital part of software development, and spreadsheets are like any other software in this respect.
This paper discusses the testing of spreadsheets in the light of one practitioner's experience. It considers the concept of software testing and how it differs from reviewing, and describes when it might take place.
Different types of testing are described, and some techniques for performing them presented. Some of the commonly encountered problems are discussed.
Sample
A widely used form of unit testing is to test for invariants; conditions that should always be true.
For example:
- Cross checking of column and row totals.
- Checking that a column of percentages add to 100%.
- Ensuring that specific values are always positive (or negative).
The tests are run every time the spreadsheet is calculated, so the results are always up to date.
It is also easy to summarise the results of these tests in one area of the spreadsheet, so that they can all be checked at once.
Publication
2004, EuSpRIG
