Modernizing Legacy Applications in PHP

Common Questions

What if we find a global in a static method?

Sometimes we will find that a static class method uses a global variable like so:

1 <?php
2 class Foo
3 {
4 static public function doSomething($baz)
5 {
6 global $bar;
7 // ... do something with $bar ...
8 }
9 }
10 ?>

This is a problem because there is no constructor to which we can move the global variable as a property. There are two options here.

The first option is to pass all the needed globals as parameters on the static method itself, thereby changing the signature of the method:

1 <?php
2 class Foo
3 {
4 static public function doSomething($bar, $baz)
5 {
6 // ... do something with $bar ...
7 }
8 }
9 ?>

We would then search the codebase for all uses of Foo::doSomething( and pass the ...