Unit Test Frameworks

Chapter 10. XMLUnit

Overview

XMLUnit provides useful support for unit testing of XML content. It is an extension to JUnit and NUnit, rather than a standalone framework.

Development and testing of software that generates XML content are common activities. Writing such tests is difficult with generic unit test frameworks. XML tests often compare expected XML content to actual XML content generated by the software that is being tested. Such tests can be written by doing a string comparison between the expected and actual XML content strings. However, what if the actual XML content contains a return character for readability, or puts XML attributes in opposite order than they appear in the expected XML string? Taken as XML documents, the two XML strings have the same contents, but an exact string comparison will fail.

To further illustrate the problem, the following pieces of XML represent an element named book containing the child elements title and author. Since the child elements are not in the same order, these XML elements have equivalent content, but different syntax:

<book> <title>Dune</title> <author>Frank Herbert</author> </book>
<book> <author>Frank Herbert</author> <title>Dune</title> </book>

The following representations of an empty XML element named library also have equal content but different syntax:

<library> </library>
<library/>

It is clearly useful to be able to test that two pieces of XML have the same content despite differences in format.

Other common test cases include ...