With static property backup, errors thrown during unserialization are not reported to the user and cause tests not to run

[Daimona]

Q	A
PHPUnit version	12.4.1
PHP version	8.4.12
Installation Method	Composer

$ composer info | sort
myclabs/deep-copy            1.13.4 Create deep copies (clones) of your objects
nikic/php-parser             5.6.1  A PHP parser written in PHP
phar-io/manifest             2.0.4  Component for reading phar.io manifest information from a PHP Archive (PHAR)
phar-io/version              3.2.1  Library for handling version information and constraints
phpunit/php-code-coverage    12.4.0 Library that provides collection, processing, and rendering functionality for PHP code coverage information.
phpunit/php-file-iterator    6.0.0  FilterIterator implementation that filters files based on a list of suffixes.
phpunit/php-invoker          6.0.0  Invoke callables with a timeout
phpunit/php-text-template    5.0.0  Simple template engine.
phpunit/php-timer            8.0.0  Utility class for timing
phpunit/phpunit              12.4.1 The PHP Unit Testing framework.
sebastian/cli-parser         4.2.0  Library for parsing CLI options
sebastian/comparator         7.1.3  Provides the functionality to compare PHP values for equality
sebastian/complexity         5.0.0  Library for calculating the complexity of PHP code units
sebastian/diff               7.0.0  Diff implementation
sebastian/environment        8.0.3  Provides functionality to handle HHVM/PHP environments
sebastian/exporter           7.0.2  Provides the functionality to export PHP variables for visualization
sebastian/global-state       8.0.2  Snapshotting of global state
sebastian/lines-of-code      4.0.0  Library for counting the lines of code in PHP source code
sebastian/object-enumerator  7.0.0  Traverses array structures and object graphs to enumerate all referenced objects
sebastian/object-reflector   5.0.0  Allows reflection of object attributes, including inherited and non-public ones
sebastian/recursion-context  7.0.1  Provides functionality to recursively process PHP variables
sebastian/type               6.0.3  Collection of value objects that represent the types of the PHP type system
sebastian/version            6.0.0  Library that helps with managing the version number of Git-hosted PHP projects
staabm/side-effects-detector 1.0.5  A static analysis tool to detect side effects in PHP code
theseer/tokenizer            1.2.3  A small library for converting tokenized PHP source code into XML and potentially other formats

$ vendor/bin/phpunit --check-php-configuration
PHPUnit 12.4.1 by Sebastian Bergmann and contributors.

Checking whether PHP is configured according to https://docs.phpunit.de/en/12.4/installation.html#configuring-php-for-development

display_errors = On         ... not ok ()
display_startup_errors = On ... not ok ()
error_reporting = -1        ... not ok (22527)
zend.assertions = 1         ... ok
assert.exception = 1        ... ok
memory_limit = -1           ... ok

(I have normal dev settings, not sure why it says "not ok")

Summary

Preconditions:

• Static property backup is enabled
• A value class V forbids serialization by throwing an error in __unserialize
• There exists somewhere a static property holding an instance of V
• This static property is initialized before tests run
• PHPUnit tries to backup that static property

The thrown error will be swallowed silently and not reported to the user.

Current behavior

There is no trace that an error occurred. Other tests in the same test class will not run. The only way to find out that something is wrong is by noticing that the number of executed tests is "lower than usual", or by individually running a test and noticing that it doesn't execute. For a codebase with many tests, errors could remain unnoticed for a long time.

How to reproduce

Minimal test case:

ValueClass.php

<?php

class ValueClass {
	public static $instance;

	public function __unserialize( array $data ): void {
		throw new Error("Cannot unserialize '$this'");
	}
}

MyTest.php

<?php

require 'ValueClass.php';

use PHPUnit\Framework\TestCase;

class MyTest extends TestCase {
	public static function setUpBeforeClass(): void {
		ValueClass::$instance = new ValueClass;
	}

	public function testFoo() {
		$this->assertTrue( true );
	}
}

And then run:

composer require --dev "phpunit/phpunit"
vendor/bin/phpunit --static-backup MyTest.php

Expected behavior

I'm not sure because I didn't check why exactly the error is swallowed. However, I think PHPUnit should either ignore the error and continue executing the test, or report the error to the user, together with the fact that the test was not executed (similar to when there is an error in a data provider).

[sebastianbergmann]

I have normal dev settings, not sure why it says "not ok"

According to the output of phpunit --check-php-configuration, your PHP environment is not configured correctly for development.

[sebastianbergmann]

I can reproduce the issue with PHPUnit 10.5, PHPUnit 11.5, and PHPUnit 12.4:

❯ ./phpunit --no-configuration --static-backup MyTest.php
PHPUnit 11.5.42-19-g278323010d by Sebastian Bergmann and contributors.

Runtime:       PHP 8.4.13
Configuration: /usr/local/src/phpunit/phpunit.xml

No tests executed!

❯ ./phpunit --no-configuration --static-backup --debug MyTest.php
PHPUnit Started (PHPUnit 11.5.42-19-g278323010d using PHP 8.4.13 (cli) on Linux)
Test Runner Configured
Event Facade Sealed
Test Suite Loaded (1 test)
Test Runner Started
Test Suite Sorted
Test Runner Execution Started (1 test)
Test Suite Started (MyTest, 1 test)
Before First Test Method Called (MyTest::setUpBeforeClass)
Before First Test Method Finished:
- MyTest::setUpBeforeClass
Test Preparation Started (MyTest::testFoo)
Test Suite Finished (MyTest, 1 test)
Test Runner Execution Finished
Test Runner Finished
PHPUnit Finished (Shell Exit Code: 0)

❯ ./phpunit --no-configuration MyTest.php
PHPUnit 11.5.42-19-g278323010d by Sebastian Bergmann and contributors.

Runtime:       PHP 8.4.13
Configuration: /usr/local/src/phpunit/phpunit.xml

.                                                                   1 / 1 (100%)

Time: 00:00.006, Memory: 4.00 MB

OK (1 test, 1 assertion)

It seems that your PHP configuration is unrelated to the issue. However, I would strongly advise you to configure your PHP environment in line with the PHPUnit documentation.

[sebastianbergmann]

This is odd: I turned your test case into a regression test case for PHPUnit but then it works for me:

tests/end-to-end/regression/6391.phpt

--TEST--
https://github.com/sebastianbergmann/phpunit/issues/6391
--FILE--
<?php declare(strict_types=1);
$_SERVER['argv'][] = '--no-configuration';
$_SERVER['argv'][] = '--do-not-cache-result';
$_SERVER['argv'][] = '--debug';
$_SERVER['argv'][] = '--static-backup';
$_SERVER['argv'][] = __DIR__ . '/6391/tests/Issue6391Test.php';

require_once __DIR__ . '/../../bootstrap.php';

(new PHPUnit\TextUI\Application)->run($_SERVER['argv']);
--EXPECTF--
PHPUnit Started (PHPUnit %s using %s)
Test Runner Configured
Event Facade Sealed
Test Suite Loaded (1 test)
Test Runner Started
Test Suite Sorted
Test Runner Execution Started (1 test)
Test Suite Started (PHPUnit\TestFixture\Issue6391\Issue6391Test, 1 test)
Before First Test Method Called (PHPUnit\TestFixture\Issue6391\Issue6391Test::setUpBeforeClass)
Before First Test Method Finished:
- PHPUnit\TestFixture\Issue6391\Issue6391Test::setUpBeforeClass
Test Preparation Started (PHPUnit\TestFixture\Issue6391\Issue6391Test::testOne)
Test Prepared (PHPUnit\TestFixture\Issue6391\Issue6391Test::testOne)
Test Passed (PHPUnit\TestFixture\Issue6391\Issue6391Test::testOne)
Test Finished (PHPUnit\TestFixture\Issue6391\Issue6391Test::testOne)
Test Suite Finished (PHPUnit\TestFixture\Issue6391\Issue6391Test, 1 test)
Test Runner Execution Finished
Test Runner Finished
PHPUnit Finished (Shell Exit Code: 0)

tests/end-to-end/regression/6391/tests/Issue6391Test.php

<?php declare(strict_types=1);
namespace PHPUnit\TestFixture\Issue6391;

use PHPUnit\Framework\TestCase;

require __DIR__ . '/../src/Issue6391.php';

final class Issue6391Test extends TestCase
{
    public static function setUpBeforeClass(): void
    {
        Issue6391::$instance = new Issue6391;
    }

    public function testOne(): void
    {
        $this->assertTrue(true);
    }
}

tests/end-to-end/regression/6391/src/Issue6391.php

<?php declare(strict_types=1);
namespace PHPUnit\TestFixture\Issue6391;

use Error;

class Issue6391
{
    public static $instance;

    public function __unserialize(array $data): void
    {
        throw new Error("Cannot unserialize '{$this}'");
    }
}