Appendix K - Equivalence Partition Example

Summary

Introduction

This appendix contains an example illustrating the testing technique of equivalence partitioning described in Chapter 3, which the test analyst can use to select specimen data for use in testing the application under test (AUT).

The Testing Problem

The specification for a software system for validating expenses claims for hotel accommodation includes the following requirements:

• There is an upper limit of £90 for accommodation expense claims

• Any claims above £90 should be rejected and cause an error message to be displayed

• All expense amounts should be greater than £0 and an error message should be displayed if this is not the case.

Analyzing the Testing Requirements

To support the process of analyzing the previous requirement, it is useful to graphically show the partitions and their boundaries and to state the ranges of the partitions with respect to the boundary values (see Figure K1).

Designing the Test Cases

The next step is to design the test cases by drawing up a table showing the test case ID, a typical value drawn from the partition to be input in the test case, the partition it tests, and the expected output or result of the test case (see Table K1).