Description
Hi, still me 😄 ,
I have a question about the LCOM4 value used and even after reseach I wasn't able to find any document or explaination.
Basically, the LCOM4 is used to calculate how many responsabilities a class have.
Now, I have a class that looks like a singleton (but it's NOT a singleton) in its structure and it should have only 1 responsability.
Here is my class:
<?php
class Foo
{
protected $a;
protected $b;
public static function build($a, $b)
{
return new self($a, $b);
}
protected function __construct($a, $b)
{
$this->a = $a;
$this->b = $b;
}
// Only accessors below, it does not matter.
//...
}
Using both PhpMetrics 1.10.0 and PhpMetrics 2.0, I can see an LCOM4 = 2 for this kind of class.
My question is: "Is LCOM4 = 2 the expected result?".
This is obvious that this class only have 1 responsability, which is build an object with it's properties. But the counter says "2" because Foo::build is related to nothing (nbWorkflow = 1) and the constructor (with all its accessors) is related to all properties (nbWorkflow = 2).
So, what is the position of the "creators" of the LCOM4 method about this? Does static methods must be ignored? In this case, a class with 6 static methods doing 6 unrelated stuffs (understand the class owns 6 responsabilities) should have an LCOM4 = 0, which is also incorrect?
Maybe because of the presence of new self in the Foo::build method, we can add the link between Foo::build and Foo::__construct, but how can we manage inheritance in this case?
I hope you understood what I wanted to explain with this issue, and if you want, I can make the same thread in French for a better understanding between us about this.
Thank you for your great tool.
Regards,