Access protected properties via public method - php

Question

I'm testing a logic flow by mocking a class and testing for the function call.
function() setUp()
{
$this->shipping_method = $this->getMockBuilder(Wc_Trincargo_Shipping_Method::class)
->getMock();
$this->shipping_method->set_post_data([
'woocommerce_wc-trinicargo-shipping_waybill_password' => 'xxx',
'woocommerce_wc-trinicargo-shipping_waybill_username' => 'xxxx',
'woocommerce_wc-trinicargo-shipping_waybill_customer_id' => uniqid(),
'woocommerce_wc-trinicargo-shipping_waybill_pickupdays' => 2
]);
}
set_post_data is a public method that sets a protected property.
Later down I test to call a another method that needs to check the said protected property. I know they say you can't mock protected and private properties but if the properties are being set by public methods....shouldn't it work?

Answer 1

If you really need to access a protected property within a test and you don't have a getter (nor should you create one purely for a test), you could use reflection.
<?php
class MyClass
{
protected $myProperty;
public function setMyProperty($value)
{
$this->myProperty = $value;
}
}
$a = new MyClass();
$a->setMyProperty('TestValue');
// echo $a->myProperty; Can't do this because it's protected.
$r = new ReflectionProperty('MyClass', 'myProperty');
$r->setAccessible(true);
$value = $r->getValue($a);
echo $value; // 'TestValue'

Answer 2

It is irrelevant that the protected property was sat from a public method. The visibility belongs to the property regardless. If you need to check the value of the property afterwards, create a public getter for that property.
Note that it is useless to test simple getters and setters. You should test what the class does with the values of the properties instead.
Example of a useless test:
class MyClass {
private $prop;
public function setProp($value) {
$this->prop = $value;
}
public function getProp() {
return $this->prop;
}
}
Test
$myClass = new MyClass();
$myClass->setProp('foo');
assertTrue($myClass->getProp() === 'foo');
Example of a class that uses a prop in a meaningful way, which determines the behavior/output of another method:
class MyClass2 {
private $prop;
public function setProp($value) {
$this->prop = $value;
}
public function getPropUpperCase() {
return strtoupper($this->prop);
}
}
Test
$myClass2 = new MyClass();
$myClass2->setProp('foo');
assertTrue($myClass->getPropUpperCase() === 'FOO');