Preparations

1. install Composer dependencies using php "which composer" install command (replace double quotes with backticks)

Testing part 1 (locator)

2. create /locator_test.php file with this content:

<?php

use ConsoleHelpers\PHPUnitCompat\AbstractTestCase as AbstractTestCaseAlias;
use Yoast\PHPUnitPolyfills\Polyfills\AssertFileDirectory;

$locate_class = require __DIR__ . '/tools/class_locator.php';

echo $locate_class(AssertFileDirectory::class) . '<br/>';
echo $locate_class(AbstractTestCaseAlias::class) . '<br/>';
echo $locate_class(NParserCompiler::class) . '<br/>';

3. open the created file in the browser
4. confirm, that output looks similar to this (you'll see full path to the In-Portal instead of ...):

.../vendor/yoast/phpunit-polyfills/src/Polyfills/AssertFileDirectory_Empty.php
.../vendor/console-helpers/phpunit-compat/src/PHPUnitCompat/AbstractTestCase5.php
.../core/kernel/nparser/compiler.php

Test part 2 (PHP version)

1. confirm, that on PHP < 5.6
   • you can't install In-Portal from the Web Browser (the /core/install.php URL)
   • you can't install In-Portal dependencies using Composer (the php "which composer" install command, but replace double quotes with backticks)
2. confirm, that on PHP >= 5.6
   • you can install In-Portal from the Web Browser (the /core/install.php URL)
   • you can install In-Portal dependencies using Composer (the php "which composer" install command, but replace double quotes with backticks)
3. confirm, that the In-Portal installation wizard shows a minimal supported PHP version in 2 places (requirement list on the left + requirement explanation on the right)