In the latest post to his MaltBlue.com site Matthew Setter takes a look at magic methods. He tries to answer a few basic questions about them - are they worth using and can you truly test effectively when they're in use.
As a freelance Zend Framework developer, I’m always looking to improve the quality of the applications I produce. So over the last 6 – 12 months, I’ve been learning as much as possible about testing. During this time, I’ve found the way I code’s dramatically changing (and improving). [...] In a recent development session, I attempted to test some of my ZendDb based classes, specifically the code which used the magic methods for dynamically building where clauses. [...] I can’t speak for what it’s like using PHPUnit’s mock objects, as I always use Mockery instead. But after attempting to do so in Mockery, I hit a stumbling block when trying to test the chained call.
His example is a call to "lessThanOrEqualTo" to create his where clause that makes use of the "__get" magic method to get and return "Where" object. After some research (and conversations on IRC) he started wondering if the magic methods were worth the trouble they may cause during testing. He references this post and lists several of the comments made about their use, most of them not in favor.