Mocking pass by reference do not work in protected methods, while in public it does

[psychob]

<?php

use PHPUnit\Framework\TestCase;

require_once './vendor/autoload.php';

class Bug
{
    public function doWork(&$test)
    {
        return true;
    }

    protected function doNotWork(&$test)
    {
        return true;
    }
}

class BugTest extends TestCase
{
    public function testWorking()
    {
        $mock = \Mockery::mock(Bug::class);
        $mock->makePartial()->shouldAllowMockingProtectedMethods();

        $test = [];

        $this->assertTrue($mock->doWork($test));
    }

    public function testNotWorking()
    {
        $mock = \Mockery::mock(Bug::class);
        $mock->makePartial()->shouldAllowMockingProtectedMethods();

        $test = [];

        $this->assertTrue($mock->doNotWork($test));
    }
}

PHPUnit 8.0.4 by Sebastian Bergmann and contributors.

.E                                                                  2 / 2 (100%)

Time: 42 ms, Memory: 4.00 MB

There was 1 error:

1) BugTest::testNotWorking
Parameter 1 to Bug::doNotWork() expected to be a reference, value given

/var/workspace/tests/Test.php:40

ERRORS!
Tests: 2, Assertions: 1, Errors: 1.

[slepic]

The error is rather strange, but shouldn't you get an error for calling protected method from outer scope instead anyway?