How do I use PHPUnit to test __construct with arguments? - php

Question

I'm new to PHPUnit, and unit testing in general. I can't seem to find a clear tutorial or resource on how best to test:
Passing no argument fails.
How to pass an argument for a constructor test.
Passing an empty argument results in the expected exception.
How would I approach testing this constructor?
<?php
class SiteManagement {
public function __construct (array $config) {
// Make sure we actually passed a config
if (empty($config)) {
throw new \Exception('Configuration not valid', 100);
}
// Sanity check the site list
if (empty($config['siteList'])) {
throw new \Exception('Site list not set', 101);
}
}
}

Answer 1

The example 2.11 of the PHPUnit documentation shows how to test exceptions.
For your specific class, it would be something like this:
$this->expectException(Exception::class);
$object = new SiteManagement([]);
You shouldn't test if the method fails without arguments unless those arguments are optional. This would be out of the scope for a unit test.

Answer 2

A good test battery for your class would be:
/** #test */
public function shouldFailWithEmptyConfig(): void
{
$config = [];
$this->expectException(\Exception::class);
$this->expectExceptionMessage('Configuration not valid');
$this->expectExceptionCode(100);
new SiteManagement($config);
}
/** #test */
public function shouldFailWithoutSiteListConfig(): void
{
$config = ['a config'];
$this->expectException(\Exception::class);
$this->expectExceptionMessage('Site list not set');
$this->expectExceptionCode(101);
new SiteManagement($config);
}
/** #test */
public function shouldMakeAFuncionality(): void
{
$config = [
'siteList' => '',
];
$siteManagement = new SiteManagement($config);
self::assertSame('expected', $siteManagement->functionality());
}