TestCase::$backupGlobals is declared as boolean but its initial value is NULL

[morozov]

Q	A
PHPUnit version	9.2.3
PHP version	7.4.7
Installation Method	Composer

Summary

In a project that uses PHPUnit and Psalm, Psalm detects the issue in PHPUnit that cannot be fixed in the project and therefore have to be suppressed.

Current behavior

ERROR: PropertyNotSetInConstructor - tests/ExampleTest.php:7:7 - Property 
Test\ExampleTest::$backupGlobals is not defined in constructor of Test\ExampleTest and in any 
methods called in the constructor (see https://psalm.dev/074)
class ExampleTest extends TestCase

The above is caused by a boolean property being non-initialized:

1. phpunit/src/Framework/TestCase.php

   Lines 63 to 66 in 61f7c75

   	/**
   	* @var bool
   	*/
   	protected $backupGlobals;

2. phpunit/src/Framework/TestCase.php

   Lines 389 to 397 in 61f7c75

   	public function __construct(?string $name = null, array $data = [], $dataName = '')
   	{
   	if ($name !== null) {
   	$this->setName($name);
   	}
   	$this->data = $data;
   	$this->dataName = $dataName;
   	}

How to reproduce

<?php declare(strict_types=1);

namespace Test;

use PHPUnit\Framework\TestCase;

class ExampleTest extends TestCase
{
    /**
     * @test
     */
    public function testExample() : void
    {
        $this->assertTrue(true);
    }
}

See the full demo project in the gist:

$ composer install
$ vendor/bin/psalm

Since the project's tests extend and use the PHPUnit test classes, suppressing errors in the vendor/ directory doesn't help.

Expected behavior

The value of $backupGlobals is always within its declared type constraints.

[sebastianbergmann]

Can you please open separate issues? Thanks!

[morozov]

Please see #4309.

[sebastianbergmann]

Please see #4309.

Thanks!