Stefan Priebsch has posted an overview of some of his experiences with test-driven development in PHP. Specifically, he talks about it in the context of a small CMS he's been working up.

The CMS I am using is a small engine that puts together (potentially multi-lingual) page content, templates, and a site structure, and creates semi-static pages. It does not have a sleek GUI frontend, because by nature I am not afraid of a text editor, and most of the time get quicker results by just writing HTML than fighting with one of these what-you-see-is-what-you-might-get HTML editors.

He talks about the configuration files containing the app's settings (inspired by the YAML Symfony uses) and his work towards the "best matching pattern" algorithm. This is where the TDD came in - he cheated a little with some base classes (tests first!) and then came up with the tests for checking template names and more complex template interactions.

The post includes drops of code here and there as well - examples of the unit tests and of the configuration files.