Prevent PHP require_once from ever running

Debugging someone else's PHP code, I'd like to selectively override one of their classes. The class is included via:

require_once('classname.php');

But, that appears in various places in the application. I'd rather 'simulate' the require_once, so that it never gets run at all. I.e. just define class classname as I want it. Then, the next time the file was require_once'ed, it'd be flagged as already-loaded and thus not reloaded.

I can create a classname.php file of my own, but I'd rather keep the testing I'm doing contained to a single file, as I'm doing this possibly for many classes, and I'd like easier control over the overriding.

In Perl, what I'd want to do would be:

$INC{'classname.pm'} = 1;

Is there a way to access PHP's equivalent of Perl's %INC?

Update: Consistently surprised by what PHP doesn't let you do...

My workaround was to use runkit's run开发者_C百科kit_method_redefine. I load the classes I was trying to prevent loading, and then redefine all the methods I was trying to 'mock', e.g.:

require_once('classname.php');
runkit_method_redefine('classname','method','$params','return "testdata";');

---

Place:

<?php return; ?>

at the very top of classname.php file.

---

Then, the next time the file was require_once'ed, it'd be flagged as already-loaded and thus not reloaded.

require_once does this for you..

Additionally you could use something hacky like

if(!class_exists("my_class")) {
  class my_class {}  // define your class here
}

---

I'm thinking what you mean is that it's entirely possible that there is another "required_once" somewhere else in the code that would cause yours to be overwritten.

There are two things you can do:

1) Hunt down the first "required" and then comment it out.

2) Go into the class file and include your class and return before the other class is defined.