Report exceptions thrown by third-party event subscribers as test run…

…ner warnings

ChangeLog-10.4.md

@@ -18,6 +18,7 @@ All notable changes of the PHPUnit 10.4 release series are documented in this fi
 * [#5505](https://github.com/sebastianbergmann/phpunit/pull/5505): Improve the failure description of `StringContains`-based assertions when the strings are encoded differently 
 * [#5515](https://github.com/sebastianbergmann/phpunit/issues/5515): The `Test\AssertionSucceeded` and `Test\AssertionFailed` events are always emitted again
 * [#5515](https://github.com/sebastianbergmann/phpunit/issues/5515): `--log-events-verbose-text` enables the export of non-scalar values for the `Test\AssertionSucceeded` and `Test\AssertionFailed` events
+* Exceptions thrown by third-party event subscribers are now reported as test runner warnings
 * The name of the top-level test suite that is created when a directory or file path is passed as an argument to the test runner is now `CLI Arguments`
 * Simplified the failure description for `assertInstanceOf()` and `assertNotInstanceOf()`
 * Simplified the failure description for `assertJson()`

src/Event/Dispatcher/DirectDispatcher.php

@@ -109,9 +109,20 @@ public function dispatch(Event $event): void
      */
     public function handleThrowable(Throwable $t): void
     {
-        if (!$this->isThrowableFromThirdPartySubscriber($t)) {
-            throw $t;
+        if ($this->isThrowableFromThirdPartySubscriber($t)) {
+            Facade::emitter()->testRunnerTriggeredWarning(
+                sprintf(
+                    'Exception in third-party event subscriber: %s%s%s',
+                    $t->getMessage(),
+                    PHP_EOL,
+                    $t->getTraceAsString(),
+                ),
+            );
+
+            return;
         }
+
+        throw $t;
     }
 
     private function isThrowableFromThirdPartySubscriber(Throwable $t): bool

tests/end-to-end/extension/_files/exception-in-extension-subscriber/phpunit.xml

@@ -0,0 +1,16 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<phpunit xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+         xsi:noNamespaceSchemaLocation="../../../../../phpunit.xsd"
+         bootstrap="src/autoload.php">
+    <extensions>
+        <bootstrap class="PHPUnit\TestFixture\Event\MyExtension\MyExtensionBootstrap">
+            <parameter name="message" value="the-message"/>
+        </bootstrap>
+    </extensions>
+
+    <testsuites>
+        <testsuite name="default">
+            <directory>tests</directory>
+        </testsuite>
+    </testsuites>
+</phpunit>

tests/end-to-end/extension/_files/exception-in-extension-subscriber/src/MyExecutionFinishedSubscriber.php

@@ -0,0 +1,22 @@
+<?php declare(strict_types=1);
+/*
+ * This file is part of PHPUnit.
+ *
+ * (c) Sebastian Bergmann <sebastian@phpunit.de>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+namespace PHPUnit\TestFixture\Event\MyExtension;
+
+use PHPUnit\Event\TestRunner\ExecutionFinished;
+use PHPUnit\Event\TestRunner\ExecutionFinishedSubscriber;
+use RuntimeException;
+
+final class MyExecutionFinishedSubscriber implements ExecutionFinishedSubscriber
+{
+    public function notify(ExecutionFinished $event): void
+    {
+        throw new RuntimeException('message');
+    }
+}

tests/end-to-end/extension/_files/exception-in-extension-subscriber/src/MyExtensionBootstrap.php

@@ -0,0 +1,23 @@
+<?php declare(strict_types=1);
+/*
+ * This file is part of PHPUnit.
+ *
+ * (c) Sebastian Bergmann <sebastian@phpunit.de>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+namespace PHPUnit\TestFixture\Event\MyExtension;
+
+use PHPUnit\Runner\Extension\Extension;
+use PHPUnit\Runner\Extension\Facade;
+use PHPUnit\Runner\Extension\ParameterCollection;
+use PHPUnit\TextUI\Configuration\Configuration;
+
+final class MyExtensionBootstrap implements Extension
+{
+    public function bootstrap(Configuration $configuration, Facade $facade, ParameterCollection $parameters): void
+    {
+        $facade->registerSubscriber(new MyExecutionFinishedSubscriber);
+    }
+}

tests/end-to-end/extension/_files/exception-in-extension-subscriber/src/autoload.php

@@ -0,0 +1,13 @@
+<?php declare(strict_types=1);
+
+/*
+ * This file is part of PHPUnit.
+ *
+ * (c) Sebastian Bergmann <sebastian@phpunit.de>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+require __DIR__ . '/MyExtensionBootstrap.php';
+
+require __DIR__ . '/MyExecutionFinishedSubscriber.php';

tests/end-to-end/extension/_files/exception-in-extension-subscriber/tests/Test.php

@@ -0,0 +1,20 @@
+<?php declare(strict_types=1);
+/*
+ * This file is part of PHPUnit.
+ *
+ * (c) Sebastian Bergmann <sebastian@phpunit.de>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+namespace PHPUnit\TestFixture\Event\MyExtension;
+
+use PHPUnit\Framework\TestCase;
+
+final class Test extends TestCase
+{
+    public function testOne(): void
+    {
+        $this->assertTrue(true);
+    }
+}

tests/end-to-end/extension/exception-in-extension-subscriber.phpt

@@ -0,0 +1,28 @@
+--TEST--
+Test runner warning is triggered when an exception is triggered in an extension's event subscriber
+--FILE--
+<?php declare(strict_types=1);
+$_SERVER['argv'][] = '--do-not-cache-result';
+$_SERVER['argv'][] = '--configuration';
+$_SERVER['argv'][] = __DIR__ . '/_files/exception-in-extension-subscriber/phpunit.xml';
+
+require __DIR__ . '/../../bootstrap.php';
+
+(new PHPUnit\TextUI\Application)->run($_SERVER['argv']);
+--EXPECTF--
+PHPUnit %s by Sebastian Bergmann and contributors.
+
+Runtime: %s
+Configuration: %s
+
+.                                                                   1 / 1 (100%)
+
+Time: %s, Memory: %s
+
+There was 1 PHPUnit test runner warning:
+
+1) Exception in third-party event subscriber: message
+%A
+
+WARNINGS!
+Tests: 1, Assertions: 1, Warnings: 1.