PHPUnit Mocking class constant - php

Question

I am testing a class that has a dependency injected. In my infinite cleverness, I scattered references to the dependency's class constant throughout my code.
(Sorry for the stupid example, wanted to deviate from foobar.)
<?php
class Book_PhoneBook extends Book {
private $author;
public function __construct(Author $author) {
$this->author = $author;
}
public function getCover() {
return $this->author->getTitle(Author::NAME_UNKNOWN) . ' - YELLOW PAGES';
}
}
class Author {
const NAME_UNKNOWN = 'anonymous';
public function getTitle($nameStyle) {
//do complicated calculation of author name
if ($nameStyle == $this::NAME_UNKNOWN) {
$name = "Anonymous";
}
//do further complicated calculations, modifying $name
return $name;
}
}
My problem is with unit tests! I'm getting "Fatal error: Undefined class constant 'NAME_UNKNOWN'" when I mock Author. The whole purpose of mocking is to avoid including the Author class file, so what is the correct way to handle that constant?
I could split Author into several objects or split the method that relies on the constant, but that would incur much repetition.

Answer 1

The fact that you are using the class constant from Author means that you are dependent on having that class available in your code and thus also in your test. So in order to test Book_PhoneBook you need to have an Author class with the constant. If the class constant is going to be a series of flags that you will need to pass to your class, you will need to have the class available and in your test make sure that the original class is loaded. You are dependent on that class for Book_PhoneBook::getCover().
You can also just use the string value of the class constant in your Book_PhoneBook though that sort of defeats the purpose of making it a constant so that you are able to change the value in one place.
With your example, it is a little tricky to get an idea of what you are trying to achieve but since you want to remove the dependency on Author in Book_PhoneBook, I would change it to something like this:
<?php
class Book_PhoneBook extends Book {
private $author;
public function __construct(Author $author) {
$this->author = $author;
}
public function getCover() {
return $this->author->getTitle() . ' - YELLOW PAGES';
}
}
class Author {
const NAME_UNKNOWN = 'anonymous';
public function __construct($nameStyle) {
$this->nameStyle = $nameStyle;
}
public function getTitle() {
//do complicated calculation of author name
if ($this->nameStyle == $this::NAME_UNKNOWN) {
$name = "Anonymous";
}
//do further complicated calculations, modifying $name
return $name;
}
}
This solution does have the problem that adding other options is difficult for getTitle. And without having a better idea of what you are trying to achieve with getTitle, I am not able to offer a better solution.

Answer 2

For anybody having a problem like this in the future, I ended up with this based on #Schleis' answer:
class Author {
const NAME_UNKNOWN = 'anonymous';
private function getTitle($nameStyle) {
//do stuff, taking $nameStyle into account
return $name;
}
public function getAnonymousTitle() {
return $this->getTitle($this::NAME_UNKNOWN);
}
}