How to gradually upgrade toward PHPUnit 6 with namespaced classes
In the latest months I wrote multiple times, in different projects, code migrating PHPUnit toward major version 6. This upgrade is harder than the previous one, since in this version it was introduced a big breaking change: all classes got (finally!) namespaced. This means that any usage of those classes in your project needs to be updated. It may seem a simple find & replace job, but since you need to introduce at least one use PHPUnit\Framework\TestCase line at the top of each one of your test classes, it’s a boring and a little more than trivial task; also, upgrading it in a single big jump may not be feasible or prudent, especially in the case of open source or distributed libraries, where backward compatibility and support for old PHP versions must be ensured.