Mutation testing is a testing technique that, due to advances in computing power, is only recently being realized as an effective testing procedure. Mutation testing is the application of the ideas presented in the field of Mutation analysis to the software development process. The basic idea is that by repeatedly modifying (mutating) the source code in a well-defined manner and testing that code to see if the mutation is handled properly the testing suite is able to model tests that no other form of testing is able to.

I propose to give PHPUnit the ability to perform mutation testing on PHP source code. I will base my design on previous mutation testing suites (particularly GCT as it is written in C) and on Jeff Offutt's work (http://ise.gmu.edu/~ofut/rsrch/mut.html).