Reverse engineering on a php function - php

Question

I know it isn't actually the reverse engineering
I have this function:
<?=$this->get('translator')->trans('dashboard.actions', array(), 'front');?>
I want to understand how to insert a function (using include maybe) that gets called when using that code.
I know the function name needs to be trans, and it has 3 arguments, but how to define it? Let me put this in a more easy way: In a php script how do I print Hello world when using $this->get('translator')->trans('dashboard.actions', array(), 'front');

Answer 1

It's just a regular class method:
class Traslator{
public function trans($a, $b, $c){
return 'Hello world';
}
}
Now, you only need another class method called get() that returns an instance of the previous class:
class Foo{
public function get(){
return new Traslator;
}
}
Full code:
<?php
class Traslator{
public function trans($a, $b, $c){
return 'Hello world';
}
}
class Foo{
public function get(){
return new Traslator;
}
public function test(){
?>
<?=$this->get('translator')->trans('dashboard.actions', array(), 'front');?>
<?php
}
}
$f = new Foo;
$f->test();

Answer 2

$this references the current object instance, and that variable may not be re-assigned. Meaning, to trick PHP into doing what you want requires to add code before and after the line you mention.
By creating a single class, the result can be obtained.
Before the <?=... line
<?php
class C {
function get($s) {
return $this;
}
function trans($s, $a, $f) {
return 'Hello world';
}
function hw() {
?>
Then the line
<?=$this->get('translator')->trans('dashboard.actions', array(), 'front');?>
Then need, to end the class, and call the method that does what you want
<?php
}}
$i = new C();
$i->hw();
Put the 3 blocks of code into a file and call PHP on it, the <?=... line should show "Hello world".

Answer 3

$this->get('translator') return instance of class lets call it "Translator" - on that instance you call trans() method
so you would like to change instance of "Translator" to your extended version
class ExtTranslator extends Translator{
public function trans($params){
echo 'fdsfds'; // here you could add what you like
return parent::trans($params);
}
}
and yes - it's hard to help you cause I don't really know what are you trying to do - to work with that code you must first understand it...