Merge branch '4.3' into 4.4

* 4.3:
  Fix displaying anonymous classes on PHP 7.4

.gitattributes

@@ -0,0 +1,3 @@
+/Tests export-ignore
+/phpunit.xml.dist export-ignore
+/.gitignore export-ignore

BufferingLogger.php

@@ -13,15 +13,22 @@ namespace Symfony\Component\Debug;
 
 use Psr\Log\AbstractLogger;
 
+@trigger_error(sprintf('The "%s" class is deprecated since Symfony 4.4, use "%s" instead.', BufferingLogger::class, \Symfony\Component\ErrorHandler\BufferingLogger::class), E_USER_DEPRECATED);
+
 /**
  * A buffering logger that stacks logs for later.
  *
  * @author Nicolas Grekas <p@tchwork.com>
+ *
+ * @deprecated since Symfony 4.4, use Symfony\Component\ErrorHandler\BufferingLogger instead.
  */
 class BufferingLogger extends AbstractLogger
 {
     private $logs = [];
 
+    /**
+     * @return void
+     */
     public function log($level, $message, array $context = [])
     {
         $this->logs[] = [$level, $message, $context];

CHANGELOG.md

@@ -1,6 +1,12 @@
 CHANGELOG
 =========
 
+4.4.0
+-----
+
+ * deprecated `FlattenException`, use the `FlattenException` of the `ErrorHandler` component
+ * deprecated the whole component in favor of the `ErrorHandler` component
+
 4.3.0
 -----
 

Debug.php

@@ -11,10 +11,14 @@
 
 namespace Symfony\Component\Debug;
 
+@trigger_error(sprintf('The "%s" class is deprecated since Symfony 4.4, use "%s" instead.', Debug::class, \Symfony\Component\ErrorHandler\Debug::class), E_USER_DEPRECATED);
+
 /**
  * Registers all the debug tools.
  *
  * @author Fabien Potencier <fabien@symfony.com>
+ *
+ * @deprecated since Symfony 4.4, use Symfony\Component\ErrorHandler\Debug instead.
  */
 class Debug
 {

DebugClassLoader.php

@@ -13,6 +13,8 @@ namespace Symfony\Component\Debug;
 
 use PHPUnit\Framework\MockObject\Matcher\StatelessInvocation;
 
+@trigger_error(sprintf('The "%s" class is deprecated since Symfony 4.4, use "%s" instead.', DebugClassLoader::class, \Symfony\Component\ErrorHandler\DebugClassLoader::class), E_USER_DEPRECATED);
+
 /**
  * Autoloader checking if the class is really defined in the file found.
  *
@@ -24,6 +26,8 @@ use PHPUnit\Framework\MockObject\Matcher\StatelessInvocation;
  * @author Christophe Coevoet <stof@notk.org>
  * @author Nicolas Grekas <p@tchwork.com>
  * @author Guilhem Niot <guilhem.niot@gmail.com>
+ *
+ * @deprecated since Symfony 4.4, use Symfony\Component\ErrorHandler\DebugClassLoader instead.
  */
 class DebugClassLoader
 {
@@ -153,11 +157,11 @@ class DebugClassLoader
                 if (!$file = $this->classLoader[0]->findFile($class) ?: false) {
                     // no-op
                 } elseif (\function_exists('opcache_is_script_cached') && @opcache_is_script_cached($file)) {
-                    require $file;
+                    include $file;
 
                     return;
-                } else {
-                    require $file;
+                } elseif (false === include $file) {
+                    return;
                 }
             } else {
                 ($this->classLoader)($class);
@@ -170,7 +174,7 @@ class DebugClassLoader
         $this->checkClass($class, $file);
     }
 
-    private function checkClass($class, $file = null)
+    private function checkClass(string $class, string $file = null)
     {
         $exists = null === $file || class_exists($class, false) || interface_exists($class, false) || trait_exists($class, false);
 
@@ -258,7 +262,7 @@ class DebugClassLoader
         }
 
         $parent = get_parent_class($class);
-        $parentAndOwnInterfaces = $this->getOwnInterfaces($class, $parent);
+        $parentAndOwnInterfaces = $this->getOwnInterfaces($class, $parent ?: null);
         if ($parent) {
             $parentAndOwnInterfaces[$parent] = $parent;
 
@@ -395,6 +399,12 @@ class DebugClassLoader
         return $deprecations;
     }
 
+    /**
+     * @param string $file
+     * @param string $class
+     *
+     * @return array|null
+     */
     public function checkCase(\ReflectionClass $refl, $file, $class)
     {
         $real = explode('\\', $class.strrchr($file, '.'));
@@ -411,7 +421,7 @@ class DebugClassLoader
         array_splice($tail, 0, $i + 1);
 
         if (!$tail) {
-            return;
+            return null;
         }
 
         $tail = \DIRECTORY_SEPARATOR.implode(\DIRECTORY_SEPARATOR, $tail);
@@ -427,12 +437,14 @@ class DebugClassLoader
         ) {
             return [substr($tail, -$tailLen + 1), substr($real, -$tailLen + 1), substr($real, 0, -$tailLen + 1)];
         }
+
+        return null;
     }
 
     /**
      * `realpath` on MacOSX doesn't normalize the case of characters.
      */
-    private function darwinRealpath($real)
+    private function darwinRealpath(string $real): string
     {
         $i = 1 + strrpos($real, '/');
         $file = substr($real, $i);
@@ -447,7 +459,11 @@ class DebugClassLoader
                 $real = self::$darwinCache[$kDir][0];
             } else {
                 $dir = getcwd();
-                chdir($real);
+
+                if (!@chdir($real)) {
+                    return $real.$file;
+                }
+
                 $real = getcwd().'/';
                 chdir($dir);
 
@@ -474,7 +490,7 @@ class DebugClassLoader
         }
 
         if (isset($dirFiles[$file])) {
-            return $real .= $dirFiles[$file];
+            return $real.$dirFiles[$file];
         }
 
         $kFile = strtolower($file);
@@ -493,18 +509,15 @@ class DebugClassLoader
             self::$darwinCache[$kDir][1] = $dirFiles;
         }
 
-        return $real .= $dirFiles[$kFile];
+        return $real.$dirFiles[$kFile];
     }
 
     /**
      * `class_implements` includes interfaces from the parents so we have to manually exclude them.
      *
-     * @param string       $class
-     * @param string|false $parent
-     *
      * @return string[]
      */
-    private function getOwnInterfaces($class, $parent)
+    private function getOwnInterfaces(string $class, ?string $parent): array
     {
         $ownInterfaces = class_implements($class, false);
 

ErrorHandler.php

@@ -23,6 +23,8 @@ use Symfony\Component\Debug\FatalErrorHandler\FatalErrorHandlerInterface;
 use Symfony\Component\Debug\FatalErrorHandler\UndefinedFunctionFatalErrorHandler;
 use Symfony\Component\Debug\FatalErrorHandler\UndefinedMethodFatalErrorHandler;
 
+@trigger_error(sprintf('The "%s" class is deprecated since Symfony 4.4, use "%s" instead.', ErrorHandler::class, \Symfony\Component\ErrorHandler\ErrorHandler::class), E_USER_DEPRECATED);
+
 /**
  * A generic ErrorHandler for the PHP engine.
  *
@@ -47,6 +49,8 @@ use Symfony\Component\Debug\FatalErrorHandler\UndefinedMethodFatalErrorHandler;
  * @author Grégoire Pineau <lyrixx@lyrixx.info>
  *
  * @final since Symfony 4.3
+ *
+ * @deprecated since Symfony 4.4, use Symfony\Component\ErrorHandler\ErrorHandler instead.
  */
 class ErrorHandler
 {
@@ -172,9 +176,8 @@ class ErrorHandler
     /**
      * Sets a logger to non assigned errors levels.
      *
-     * @param LoggerInterface $logger  A PSR-3 logger to put as default for the given levels
-     * @param array|int       $levels  An array map of E_* to LogLevel::* or an integer bit field of E_* constants
-     * @param bool            $replace Whether to replace or not any existing logger
+     * @param array|int $levels  An array map of E_* to LogLevel::* or an integer bit field of E_* constants
+     * @param bool      $replace Whether to replace or not any existing logger
      */
     public function setDefaultLogger(LoggerInterface $logger, $levels = E_ALL, $replace = false)
     {
@@ -349,7 +352,7 @@ class ErrorHandler
     /**
      * Re-registers as a PHP error handler if levels changed.
      */
-    private function reRegister($prev)
+    private function reRegister(int $prev)
     {
         if ($prev !== $this->thrownErrors | $this->loggedErrors) {
             $handler = set_error_handler('var_dump');
@@ -382,8 +385,7 @@ class ErrorHandler
      */
     public function handleError($type, $message, $file, $line)
     {
-        // @deprecated to be removed in Symfony 5.0
-        if (\PHP_VERSION_ID >= 70300 && $message && '"' === $message[0] && 0 === strpos($message, '"continue') && preg_match('/^"continue(?: \d++)?" targeting switch is equivalent to "break(?: \d++)?"\. Did you mean to use "continue(?: \d++)?"\?$/', $message)) {
+        if (\PHP_VERSION_ID >= 70300 && E_WARNING === $type && '"' === $message[0] && false !== strpos($message, '" targeting switch is equivalent to "break')) {
             $type = E_DEPRECATED;
         }
 
@@ -443,7 +445,7 @@ class ErrorHandler
                 self::$silencedErrorCache[$id][$message] = $errorAsException;
             }
             if (null === $lightTrace) {
-                return;
+                return true;
             }
         } else {
             $errorAsException = new \ErrorException($logMessage, 0, $type, $file, $line);
@@ -459,7 +461,7 @@ class ErrorHandler
         }
 
         if ($throw) {
-            if (E_USER_ERROR & $type) {
+            if (\PHP_VERSION_ID < 70400 && E_USER_ERROR & $type) {
                 for ($i = 1; isset($backtrace[$i]); ++$i) {
                     if (isset($backtrace[$i]['function'], $backtrace[$i]['type'], $backtrace[$i - 1]['function'])
                         && '__toString' === $backtrace[$i]['function']
@@ -576,7 +578,9 @@ class ErrorHandler
         $this->exceptionHandler = null;
         try {
             if (null !== $exceptionHandler) {
-                return $exceptionHandler($exception);
+                $exceptionHandler($exception);
+
+                return;
             }
             $handlerException = $handlerException ?: $exception;
         } catch (\Throwable $handlerException) {
@@ -687,7 +691,7 @@ class ErrorHandler
     /**
      * Cleans the trace by removing function arguments and the frames added by the error handler and DebugClassLoader.
      */
-    private function cleanTrace($backtrace, $type, $file, $line, $throw)
+    private function cleanTrace(array $backtrace, int $type, string $file, int $line, bool $throw): array
     {
         $lightTrace = $backtrace;
 

Exception/ClassNotFoundException.php

@@ -11,10 +11,14 @@
 
 namespace Symfony\Component\Debug\Exception;
 
+@trigger_error(sprintf('The "%s" class is deprecated since Symfony 4.4, use "%s" instead.', ClassNotFoundException::class, \Symfony\Component\ErrorHandler\Error\ClassNotFoundError::class), E_USER_DEPRECATED);
+
 /**
  * Class (or Trait or Interface) Not Found Exception.
  *
  * @author Konstanton Myakshin <koc-dp@yandex.ru>
+ *
+ * @deprecated since Symfony 4.4, use Symfony\Component\ErrorHandler\Error\ClassNotFoundError instead.
  */
 class ClassNotFoundException extends FatalErrorException
 {

Exception/FatalErrorException.php

@@ -11,10 +11,14 @@
 
 namespace Symfony\Component\Debug\Exception;
 
+@trigger_error(sprintf('The "%s" class is deprecated since Symfony 4.4, use "%s" instead.', FatalErrorException::class, \Symfony\Component\ErrorHandler\Error\FatalError::class), E_USER_DEPRECATED);
+
 /**
  * Fatal Error Exception.
  *
  * @author Konstanton Myakshin <koc-dp@yandex.ru>
+ *
+ * @deprecated since Symfony 4.4, use Symfony\Component\ErrorHandler\Error\FatalError instead.
  */
 class FatalErrorException extends \ErrorException
 {

Exception/FatalThrowableError.php

@@ -11,10 +11,14 @@
 
 namespace Symfony\Component\Debug\Exception;
 
+@trigger_error(sprintf('The "%s" class is deprecated since Symfony 4.4.', FatalThrowableError::class), E_USER_DEPRECATED);
+
 /**
  * Fatal Throwable Error.
  *
  * @author Nicolas Grekas <p@tchwork.com>
+ *
+ * @deprecated since Symfony 4.4
  */
 class FatalThrowableError extends FatalErrorException
 {

Exception/FlattenException.php

@@ -20,6 +20,8 @@ use Symfony\Component\HttpKernel\Exception\HttpExceptionInterface;
  * Basically, this class removes all objects from the trace.
  *
  * @author Fabien Potencier <fabien@symfony.com>
+ *
+ * @deprecated since Symfony 4.4, use Symfony\Component\ErrorHandler\Exception\FlattenException instead.
  */
 class FlattenException
 {
@@ -34,12 +36,18 @@ class FlattenException
     private $file;
     private $line;
 
+    /**
+     * @return static
+     */
     public static function create(\Exception $exception, $statusCode = null, array $headers = [])
     {
         return static::createFromThrowable($exception, $statusCode, $headers);
     }
 
-    public static function createFromThrowable(\Throwable $exception, ?int $statusCode = null, array $headers = []): self
+    /**
+     * @return static
+     */
+    public static function createFromThrowable(\Throwable $exception, int $statusCode = null, array $headers = [])
     {
         $e = new static();
         $e->setMessage($exception->getMessage());
@@ -172,7 +180,7 @@ class FlattenException
     public function setMessage($message)
     {
         if (false !== strpos($message, "class@anonymous\0")) {
-            $message = preg_replace_callback('/class@anonymous\x00.*?\.php0x?[0-9a-fA-F]++/', function ($m) {
+            $message = preg_replace_callback('/class@anonymous\x00.*?\.php(?:0x?|:)[0-9a-fA-F]++/', function ($m) {
                 return class_exists($m[0], false) ? get_parent_class($m[0]).'@anonymous' : $m[0];
             }, $message);
         }
@@ -285,7 +293,7 @@ class FlattenException
         return $this;
     }
 
-    private function flattenArgs($args, $level = 0, &$count = 0)
+    private function flattenArgs(array $args, int $level = 0, int &$count = 0): array
     {
         $result = [];
         foreach ($args as $key => $value) {
@@ -321,7 +329,7 @@ class FlattenException
         return $result;
     }
 
-    private function getClassNameFromIncomplete(\__PHP_Incomplete_Class $value)
+    private function getClassNameFromIncomplete(\__PHP_Incomplete_Class $value): string
     {
         $array = new \ArrayObject($value);
 

Exception/OutOfMemoryException.php

@@ -11,10 +11,14 @@
 
 namespace Symfony\Component\Debug\Exception;
 
+@trigger_error(sprintf('The "%s" class is deprecated since Symfony 4.4, use "%s" instead.', OutOfMemoryException::class, \Symfony\Component\ErrorHandler\Error\OutOfMemoryError::class), E_USER_DEPRECATED);
+
 /**
  * Out of memory exception.
  *
  * @author Nicolas Grekas <p@tchwork.com>
+ *
+ * @deprecated since Symfony 4.4, use Symfony\Component\ErrorHandler\Error\OutOfMemoryError instead.
  */
 class OutOfMemoryException extends FatalErrorException
 {

Exception/SilencedErrorContext.php

@@ -11,10 +11,14 @@
 
 namespace Symfony\Component\Debug\Exception;
 
+@trigger_error(sprintf('The "%s" class is deprecated since Symfony 4.4, use "%s" instead.', SilencedErrorContext::class, \Symfony\Component\ErrorHandler\Exception\SilencedErrorContext::class), E_USER_DEPRECATED);
+
 /**
  * Data Object that represents a Silenced Error.
  *
  * @author Grégoire Pineau <lyrixx@lyrixx.info>
+ *
+ * @deprecated since Symfony 4.4, use Symfony\Component\ErrorHandler\Exception\SilencedErrorContext instead.
  */
 class SilencedErrorContext implements \JsonSerializable
 {
@@ -54,7 +58,7 @@ class SilencedErrorContext implements \JsonSerializable
         return $this->trace;
     }
 
-    public function JsonSerialize()
+    public function jsonSerialize()
     {
         return [
             'severity' => $this->severity,

Exception/UndefinedFunctionException.php

@@ -11,10 +11,14 @@
 
 namespace Symfony\Component\Debug\Exception;
 
+@trigger_error(sprintf('The "%s" class is deprecated since Symfony 4.4, use "%s" instead.', UndefinedFunctionException::class, \Symfony\Component\ErrorHandler\Error\UndefinedFunctionError::class), E_USER_DEPRECATED);
+
 /**
  * Undefined Function Exception.
  *
  * @author Konstanton Myakshin <koc-dp@yandex.ru>
+ *
+ * @deprecated since Symfony 4.4, use Symfony\Component\ErrorHandler\Error\UndefinedFunctionError instead.
  */
 class UndefinedFunctionException extends FatalErrorException
 {

Exception/UndefinedMethodException.php

@@ -11,10 +11,14 @@
 
 namespace Symfony\Component\Debug\Exception;
 
+@trigger_error(sprintf('The "%s" class is deprecated since Symfony 4.4, use "%s" instead.', UndefinedMethodException::class, \Symfony\Component\ErrorHandler\Error\UndefinedMethodError::class), E_USER_DEPRECATED);
+
 /**
  * Undefined Method Exception.
  *
  * @author Grégoire Pineau <lyrixx@lyrixx.info>
+ *
+ * @deprecated since Symfony 4.4, use Symfony\Component\ErrorHandler\Error\UndefinedMethodError instead.
  */
 class UndefinedMethodException extends FatalErrorException
 {

FatalErrorHandler/ClassNotFoundFatalErrorHandler.php

@@ -17,10 +17,14 @@ use Symfony\Component\Debug\DebugClassLoader;
 use Symfony\Component\Debug\Exception\ClassNotFoundException;
 use Symfony\Component\Debug\Exception\FatalErrorException;
 
+@trigger_error(sprintf('The "%s" class is deprecated since Symfony 4.4, use "%s" instead.', ClassNotFoundFatalErrorHandler::class, \Symfony\Component\ErrorHandler\FatalErrorHandler\ClassNotFoundFatalErrorHandler::class), E_USER_DEPRECATED);
+
 /**
  * ErrorHandler for classes that do not exist.
  *
  * @author Fabien Potencier <fabien@symfony.com>
+ *
+ * @deprecated since Symfony 4.4, use Symfony\Component\ErrorHandler\FatalErrorHandler\ClassNotFoundFatalErrorHandler instead.
  */
 class ClassNotFoundFatalErrorHandler implements FatalErrorHandlerInterface
 {
@@ -33,11 +37,11 @@ class ClassNotFoundFatalErrorHandler implements FatalErrorHandlerInterface
         $notFoundSuffix = '\' not found';
         $notFoundSuffixLen = \strlen($notFoundSuffix);
         if ($notFoundSuffixLen > $messageLen) {
-            return;
+            return null;
         }
 
         if (0 !== substr_compare($error['message'], $notFoundSuffix, -$notFoundSuffixLen)) {
-            return;
+            return null;
         }
 
         foreach (['class', 'interface', 'trait'] as $typeName) {
@@ -71,6 +75,8 @@ class ClassNotFoundFatalErrorHandler implements FatalErrorHandlerInterface
 
             return new ClassNotFoundException($message, $exception);
         }
+
+        return null;
     }
 
     /**

FatalErrorHandler/FatalErrorHandlerInterface.php

@@ -13,18 +13,21 @@ namespace Symfony\Component\Debug\FatalErrorHandler;
 
 use Symfony\Component\Debug\Exception\FatalErrorException;
 
+@trigger_error(sprintf('The "%s" class is deprecated since Symfony 4.4, use "%s" instead.', FatalErrorHandlerInterface::class, \Symfony\Component\ErrorHandler\FatalErrorHandler\FatalErrorHandlerInterface::class), E_USER_DEPRECATED);
+
 /**
  * Attempts to convert fatal errors to exceptions.
  *
  * @author Fabien Potencier <fabien@symfony.com>
+ *
+ * @deprecated since Symfony 4.4, use Symfony\Component\ErrorHandler\FatalErrorHandler\FatalErrorHandlerInterface instead.
  */
 interface FatalErrorHandlerInterface
 {
     /**
      * Attempts to convert an error into an exception.
      *
-     * @param array               $error     An array as returned by error_get_last()
-     * @param FatalErrorException $exception A FatalErrorException instance
+     * @param array $error An array as returned by error_get_last()
      *
      * @return FatalErrorException|null A FatalErrorException instance if the class is able to convert the error, null otherwise
      */

FatalErrorHandler/UndefinedFunctionFatalErrorHandler.php

@@ -14,10 +14,14 @@ namespace Symfony\Component\Debug\FatalErrorHandler;
 use Symfony\Component\Debug\Exception\FatalErrorException;
 use Symfony\Component\Debug\Exception\UndefinedFunctionException;
 
+@trigger_error(sprintf('The "%s" class is deprecated since Symfony 4.4, use "%s" instead.', UndefinedFunctionFatalErrorHandler::class, \Symfony\Component\ErrorHandler\ErrorEnhancer\UndefinedFunctionErrorEnhancer::class), E_USER_DEPRECATED);
+
 /**
  * ErrorHandler for undefined functions.
  *
  * @author Fabien Potencier <fabien@symfony.com>
+ *
+ * @deprecated since Symfony 4.4, use Symfony\Component\ErrorHandler\ErrorEnhancer\UndefinedFunctionErrorEnhancer instead.
  */
 class UndefinedFunctionFatalErrorHandler implements FatalErrorHandlerInterface
 {
@@ -30,17 +34,17 @@ class UndefinedFunctionFatalErrorHandler implements FatalErrorHandlerInterface
         $notFoundSuffix = '()';
         $notFoundSuffixLen = \strlen($notFoundSuffix);
         if ($notFoundSuffixLen > $messageLen) {
-            return;
+            return null;
         }
 
         if (0 !== substr_compare($error['message'], $notFoundSuffix, -$notFoundSuffixLen)) {
-            return;
+            return null;
         }
 
         $prefix = 'Call to undefined function ';
         $prefixLen = \strlen($prefix);
         if (0 !== strpos($error['message'], $prefix)) {
-            return;
+            return null;
         }
 
         $fullyQualifiedFunctionName = substr($error['message'], $prefixLen, -$notFoundSuffixLen);

FatalErrorHandler/UndefinedMethodFatalErrorHandler.php

@@ -14,10 +14,14 @@ namespace Symfony\Component\Debug\FatalErrorHandler;
 use Symfony\Component\Debug\Exception\FatalErrorException;
 use Symfony\Component\Debug\Exception\UndefinedMethodException;
 
+@trigger_error(sprintf('The "%s" class is deprecated since Symfony 4.4, use "%s" instead.', UndefinedMethodFatalErrorHandler::class, \Symfony\Component\ErrorHandler\ErrorEnhancer\UndefinedMethodErrorEnhancer::class), E_USER_DEPRECATED);
+
 /**
  * ErrorHandler for undefined methods.
  *
  * @author Grégoire Pineau <lyrixx@lyrixx.info>
+ *
+ * @deprecated since Symfony 4.4, use Symfony\Component\ErrorHandler\ErrorEnhancer\UndefinedMethodErrorEnhancer instead.
  */
 class UndefinedMethodFatalErrorHandler implements FatalErrorHandlerInterface
 {
@@ -28,7 +32,7 @@ class UndefinedMethodFatalErrorHandler implements FatalErrorHandlerInterface
     {
         preg_match('/^Call to undefined method (.*)::(.*)\(\)$/', $error['message'], $matches);
         if (!$matches) {
-            return;
+            return null;
         }
 
         $className = $matches[1];

README.md

@@ -1,12 +1,16 @@
 Debug Component
 ===============
 
+**CAUTION**: this component is deprecated since Symfony 4.4. Instead, use the
+[ErrorHandler component](https://github.com/symfony/symfony/tree/master/src/Symfony/Component/ErrorHandler).
+
+-----
+
 The Debug component provides tools to ease debugging PHP code.
 
 Resources
 ---------
 
-  * [Documentation](https://symfony.com/doc/current/components/debug/index.html)
   * [Contributing](https://symfony.com/doc/current/contributing/index.html)
   * [Report issues](https://github.com/symfony/symfony/issues) and
     [send Pull Requests](https://github.com/symfony/symfony/pulls)

Tests/DebugClassLoaderTest.php

@@ -14,6 +14,9 @@ namespace Symfony\Component\Debug\Tests;
 use PHPUnit\Framework\TestCase;
 use Symfony\Component\Debug\DebugClassLoader;
 
+/**
+ * @group legacy
+ */
 class DebugClassLoaderTest extends TestCase
 {
     /**
@@ -23,24 +26,26 @@ class DebugClassLoaderTest extends TestCase
 
     private $loader;
 
-    protected function setUp()
+    protected function setUp(): void
     {
         $this->errorReporting = error_reporting(E_ALL);
-        $this->loader = new ClassLoader();
-        spl_autoload_register([$this->loader, 'loadClass'], true, true);
-        DebugClassLoader::enable();
+        $this->loader = [new DebugClassLoader([new ClassLoader(), 'loadClass']), 'loadClass'];
+        spl_autoload_register($this->loader, true, true);
     }
 
-    protected function tearDown()
+    protected function tearDown(): void
     {
-        DebugClassLoader::disable();
-        spl_autoload_unregister([$this->loader, 'loadClass']);
+        spl_autoload_unregister($this->loader);
         error_reporting($this->errorReporting);
     }
 
+    /**
+     * @runInSeparateProcess
+     */
     public function testIdempotence()
     {
         DebugClassLoader::enable();
+        DebugClassLoader::enable();
 
         $functions = spl_autoload_functions();
         foreach ($functions as $function) {
@@ -58,49 +63,43 @@ class DebugClassLoaderTest extends TestCase
         $this->fail('DebugClassLoader did not register');
     }
 
-    /**
-     * @expectedException \Exception
-     * @expectedExceptionMessage boo
-     */
     public function testThrowingClass()
     {
+        $this->expectException('Exception');
+        $this->expectExceptionMessage('boo');
         try {
-            class_exists(__NAMESPACE__.'\Fixtures\Throwing');
+            class_exists(Fixtures\Throwing::class);
             $this->fail('Exception expected');
         } catch (\Exception $e) {
             $this->assertSame('boo', $e->getMessage());
         }
 
         // the second call also should throw
-        class_exists(__NAMESPACE__.'\Fixtures\Throwing');
+        class_exists(Fixtures\Throwing::class);
     }
 
-    /**
-     * @expectedException \RuntimeException
-     */
     public function testNameCaseMismatch()
     {
-        class_exists(__NAMESPACE__.'\TestingCaseMismatch', true);
+        $this->expectException('RuntimeException');
+        $this->expectExceptionMessage('Case mismatch between loaded and declared class names');
+        class_exists(TestingCaseMismatch::class, true);
     }
 
-    /**
-     * @expectedException \RuntimeException
-     * @expectedExceptionMessage Case mismatch between class and real file names
-     */
     public function testFileCaseMismatch()
     {
+        $this->expectException('RuntimeException');
+        $this->expectExceptionMessage('Case mismatch between class and real file names');
         if (!file_exists(__DIR__.'/Fixtures/CaseMismatch.php')) {
             $this->markTestSkipped('Can only be run on case insensitive filesystems');
         }
 
-        class_exists(__NAMESPACE__.'\Fixtures\CaseMismatch', true);
+        class_exists(Fixtures\CaseMismatch::class, true);
     }
 
-    /**
-     * @expectedException \RuntimeException
-     */
     public function testPsr4CaseMismatch()
     {
+        $this->expectException('RuntimeException');
+        $this->expectExceptionMessage('Case mismatch between loaded and declared class names');
         class_exists(__NAMESPACE__.'\Fixtures\Psr4CaseMismatch', true);
     }
 
@@ -116,7 +115,7 @@ class DebugClassLoaderTest extends TestCase
 
     public function testClassAlias()
     {
-        $this->assertTrue(class_exists(__NAMESPACE__.'\Fixtures\ClassAlias', true));
+        $this->assertTrue(class_exists(Fixtures\ClassAlias::class, true));
     }
 
     /**
@@ -158,7 +157,7 @@ class DebugClassLoaderTest extends TestCase
         $e = error_reporting(0);
         trigger_error('', E_USER_NOTICE);
 
-        class_exists('Test\\'.__NAMESPACE__.'\\NonDeprecatedInterfaceClass', true);
+        class_exists('Test\\'.NonDeprecatedInterfaceClass::class, true);
 
         error_reporting($e);
         restore_error_handler();
@@ -205,7 +204,7 @@ class DebugClassLoaderTest extends TestCase
         require __DIR__.'/Fixtures/FinalClasses.php';
 
         $i = 1;
-        while (class_exists($finalClass = __NAMESPACE__.'\\Fixtures\\FinalClass'.$i++, false)) {
+        while (class_exists($finalClass = Fixtures\FinalClass::class.$i++, false)) {
             spl_autoload_call($finalClass);
             class_exists('Test\\'.__NAMESPACE__.'\\Extends'.substr($finalClass, strrpos($finalClass, '\\') + 1), true);
         }
@@ -231,7 +230,7 @@ class DebugClassLoaderTest extends TestCase
         set_error_handler(function ($type, $msg) use (&$deprecations) { $deprecations[] = $msg; });
         $e = error_reporting(E_USER_DEPRECATED);
 
-        class_exists(__NAMESPACE__.'\\Fixtures\\ExtendedFinalMethod', true);
+        class_exists(Fixtures\ExtendedFinalMethod::class, true);
 
         error_reporting($e);
         restore_error_handler();
@@ -250,7 +249,7 @@ class DebugClassLoaderTest extends TestCase
         $e = error_reporting(0);
         trigger_error('', E_USER_NOTICE);
 
-        class_exists('Test\\'.__NAMESPACE__.'\\ExtendsAnnotatedClass', true);
+        class_exists('Test\\'.ExtendsAnnotatedClass::class, true);
 
         error_reporting($e);
         restore_error_handler();
@@ -267,7 +266,7 @@ class DebugClassLoaderTest extends TestCase
         set_error_handler(function ($type, $msg) use (&$deprecations) { $deprecations[] = $msg; });
         $e = error_reporting(E_USER_DEPRECATED);
 
-        class_exists('Test\\'.__NAMESPACE__.'\\ExtendsInternals', true);
+        class_exists('Test\\'.ExtendsInternals::class, true);
 
         error_reporting($e);
         restore_error_handler();
@@ -286,7 +285,7 @@ class DebugClassLoaderTest extends TestCase
         set_error_handler(function ($type, $msg) use (&$deprecations) { $deprecations[] = $msg; });
         $e = error_reporting(E_USER_DEPRECATED);
 
-        class_exists(__NAMESPACE__.'\\Fixtures\SubClassWithAnnotatedParameters', true);
+        class_exists(Fixtures\SubClassWithAnnotatedParameters::class, true);
 
         error_reporting($e);
         restore_error_handler();
@@ -309,7 +308,7 @@ class DebugClassLoaderTest extends TestCase
         set_error_handler(function ($type, $msg) use (&$deprecations) { $deprecations[] = $msg; });
         $e = error_reporting(E_USER_DEPRECATED);
 
-        class_exists('Test\\'.__NAMESPACE__.'\\UseTraitWithInternalMethod', true);
+        class_exists('Test\\'.UseTraitWithInternalMethod::class, true);
 
         error_reporting($e);
         restore_error_handler();
@@ -323,7 +322,7 @@ class DebugClassLoaderTest extends TestCase
         set_error_handler(function ($type, $msg) use (&$deprecations) { $deprecations[] = $msg; });
         $e = error_reporting(E_USER_DEPRECATED);
 
-        class_exists('Test\\'.__NAMESPACE__.'\\ExtendsVirtual', true);
+        class_exists('Test\\'.ExtendsVirtual::class, true);
 
         error_reporting($e);
         restore_error_handler();
@@ -349,7 +348,7 @@ class DebugClassLoaderTest extends TestCase
         set_error_handler(function ($type, $msg) use (&$deprecations) { $deprecations[] = $msg; });
         $e = error_reporting(E_USER_DEPRECATED);
 
-        class_exists('Test\\'.__NAMESPACE__.'\\ExtendsVirtualMagicCall', true);
+        class_exists('Test\\'.ExtendsVirtualMagicCall::class, true);
 
         error_reporting($e);
         restore_error_handler();
@@ -359,7 +358,7 @@ class DebugClassLoaderTest extends TestCase
 
     public function testEvaluatedCode()
     {
-        $this->assertTrue(class_exists(__NAMESPACE__.'\Fixtures\DefinitionInEvaluatedCode', true));
+        $this->assertTrue(class_exists(Fixtures\DefinitionInEvaluatedCode::class, true));
     }
 }
 
@@ -378,11 +377,11 @@ class ClassLoader
     {
         $fixtureDir = __DIR__.\DIRECTORY_SEPARATOR.'Fixtures'.\DIRECTORY_SEPARATOR;
 
-        if (__NAMESPACE__.'\TestingUnsilencing' === $class) {
+        if (TestingUnsilencing::class === $class) {
             eval('-- parse error --');
-        } elseif (__NAMESPACE__.'\TestingStacking' === $class) {
+        } elseif (TestingStacking::class === $class) {
             eval('namespace '.__NAMESPACE__.'; class TestingStacking { function foo() {} }');
-        } elseif (__NAMESPACE__.'\TestingCaseMismatch' === $class) {
+        } elseif (TestingCaseMismatch::class === $class) {
             eval('namespace '.__NAMESPACE__.'; class TestingCaseMisMatch {}');
         } elseif (__NAMESPACE__.'\Fixtures\Psr4CaseMismatch' === $class) {
             return $fixtureDir.'psr4'.\DIRECTORY_SEPARATOR.'Psr4CaseMismatch.php';
@@ -392,55 +391,55 @@ class ClassLoader
             return $fixtureDir.'notPsr0Bis.php';
         } elseif ('Symfony\Bridge\Debug\Tests\Fixtures\ExtendsDeprecatedParent' === $class) {
             eval('namespace Symfony\Bridge\Debug\Tests\Fixtures; class ExtendsDeprecatedParent extends \\'.__NAMESPACE__.'\Fixtures\DeprecatedClass {}');
-        } elseif ('Test\\'.__NAMESPACE__.'\DeprecatedParentClass' === $class) {
+        } elseif ('Test\\'.DeprecatedParentClass::class === $class) {
             eval('namespace Test\\'.__NAMESPACE__.'; class DeprecatedParentClass extends \\'.__NAMESPACE__.'\Fixtures\DeprecatedClass {}');
-        } elseif ('Test\\'.__NAMESPACE__.'\DeprecatedInterfaceClass' === $class) {
+        } elseif ('Test\\'.DeprecatedInterfaceClass::class === $class) {
             eval('namespace Test\\'.__NAMESPACE__.'; class DeprecatedInterfaceClass implements \\'.__NAMESPACE__.'\Fixtures\DeprecatedInterface {}');
-        } elseif ('Test\\'.__NAMESPACE__.'\NonDeprecatedInterfaceClass' === $class) {
+        } elseif ('Test\\'.NonDeprecatedInterfaceClass::class === $class) {
             eval('namespace Test\\'.__NAMESPACE__.'; class NonDeprecatedInterfaceClass implements \\'.__NAMESPACE__.'\Fixtures\NonDeprecatedInterface {}');
-        } elseif ('Test\\'.__NAMESPACE__.'\Float' === $class) {
+        } elseif ('Test\\'.Float::class === $class) {
             eval('namespace Test\\'.__NAMESPACE__.'; class Float {}');
-        } elseif (0 === strpos($class, 'Test\\'.__NAMESPACE__.'\ExtendsFinalClass')) {
+        } elseif (0 === strpos($class, 'Test\\'.ExtendsFinalClass::class)) {
             $classShortName = substr($class, strrpos($class, '\\') + 1);
             eval('namespace Test\\'.__NAMESPACE__.'; class '.$classShortName.' extends \\'.__NAMESPACE__.'\Fixtures\\'.substr($classShortName, 7).' {}');
-        } elseif ('Test\\'.__NAMESPACE__.'\ExtendsAnnotatedClass' === $class) {
+        } elseif ('Test\\'.ExtendsAnnotatedClass::class === $class) {
             eval('namespace Test\\'.__NAMESPACE__.'; class ExtendsAnnotatedClass extends \\'.__NAMESPACE__.'\Fixtures\AnnotatedClass {
                 public function deprecatedMethod() { }
             }');
-        } elseif ('Test\\'.__NAMESPACE__.'\ExtendsInternals' === $class) {
+        } elseif ('Test\\'.ExtendsInternals::class === $class) {
             eval('namespace Test\\'.__NAMESPACE__.'; class ExtendsInternals extends ExtendsInternalsParent {
                 use \\'.__NAMESPACE__.'\Fixtures\InternalTrait;
 
                 public function internalMethod() { }
             }');
-        } elseif ('Test\\'.__NAMESPACE__.'\ExtendsInternalsParent' === $class) {
+        } elseif ('Test\\'.ExtendsInternalsParent::class === $class) {
             eval('namespace Test\\'.__NAMESPACE__.'; class ExtendsInternalsParent extends \\'.__NAMESPACE__.'\Fixtures\InternalClass implements \\'.__NAMESPACE__.'\Fixtures\InternalInterface { }');
-        } elseif ('Test\\'.__NAMESPACE__.'\UseTraitWithInternalMethod' === $class) {
+        } elseif ('Test\\'.UseTraitWithInternalMethod::class === $class) {
             eval('namespace Test\\'.__NAMESPACE__.'; class UseTraitWithInternalMethod { use \\'.__NAMESPACE__.'\Fixtures\TraitWithInternalMethod; }');
-        } elseif ('Test\\'.__NAMESPACE__.'\ExtendsVirtual' === $class) {
+        } elseif ('Test\\'.ExtendsVirtual::class === $class) {
             eval('namespace Test\\'.__NAMESPACE__.'; class ExtendsVirtual extends ExtendsVirtualParent implements \\'.__NAMESPACE__.'\Fixtures\VirtualSubInterface {
                 public function ownClassMethod() { }
                 public function classMethod() { }
                 public function sameLineInterfaceMethodNoBraces() { }
             }');
-        } elseif ('Test\\'.__NAMESPACE__.'\ExtendsVirtualParent' === $class) {
+        } elseif ('Test\\'.ExtendsVirtualParent::class === $class) {
             eval('namespace Test\\'.__NAMESPACE__.'; class ExtendsVirtualParent extends ExtendsVirtualAbstract {
                 public function ownParentMethod() { }
                 public function traitMethod() { }
                 public function sameLineInterfaceMethod() { }
                 public function staticMethodNoBraces() { } // should be static
             }');
-        } elseif ('Test\\'.__NAMESPACE__.'\ExtendsVirtualAbstract' === $class) {
+        } elseif ('Test\\'.ExtendsVirtualAbstract::class === $class) {
             eval('namespace Test\\'.__NAMESPACE__.'; abstract class ExtendsVirtualAbstract extends ExtendsVirtualAbstractBase {
                 public static function staticMethod() { }
                 public function ownAbstractMethod() { }
                 public function interfaceMethod() { }
             }');
-        } elseif ('Test\\'.__NAMESPACE__.'\ExtendsVirtualAbstractBase' === $class) {
+        } elseif ('Test\\'.ExtendsVirtualAbstractBase::class === $class) {
             eval('namespace Test\\'.__NAMESPACE__.'; abstract class ExtendsVirtualAbstractBase extends \\'.__NAMESPACE__.'\Fixtures\VirtualClass implements \\'.__NAMESPACE__.'\Fixtures\VirtualInterface {
                 public function ownAbstractBaseMethod() { }
             }');
-        } elseif ('Test\\'.__NAMESPACE__.'\ExtendsVirtualMagicCall' === $class) {
+        } elseif ('Test\\'.ExtendsVirtualMagicCall::class === $class) {
             eval('namespace Test\\'.__NAMESPACE__.'; class ExtendsVirtualMagicCall extends \\'.__NAMESPACE__.'\Fixtures\VirtualClassMagicCall implements \\'.__NAMESPACE__.'\Fixtures\VirtualInterface {
             }');
         }

Tests/ErrorHandlerTest.php

@@ -25,6 +25,8 @@ use Symfony\Component\Debug\Tests\Fixtures\LoggerThatSetAnErrorHandler;
  *
  * @author Robert Schönthal <seroscho@googlemail.com>
  * @author Nicolas Grekas <p@tchwork.com>
+ *
+ * @group legacy
  */
 class ErrorHandlerTest extends TestCase
 {
@@ -70,8 +72,8 @@ class ErrorHandlerTest extends TestCase
 
     public function testErrorGetLast()
     {
-        $handler = ErrorHandler::register();
         $logger = $this->getMockBuilder('Psr\Log\LoggerInterface')->getMock();
+        $handler = ErrorHandler::register();
         $handler->setDefaultLogger($logger);
         $handler->screamAt(E_ALL);
 
@@ -143,9 +145,8 @@ class ErrorHandlerTest extends TestCase
     public function testDefaultLogger()
     {
         try {
-            $handler = ErrorHandler::register();
-
             $logger = $this->getMockBuilder('Psr\Log\LoggerInterface')->getMock();
+            $handler = ErrorHandler::register();
 
             $handler->setDefaultLogger($logger, E_NOTICE);
             $handler->setDefaultLogger($logger, [E_USER_NOTICE => LogLevel::CRITICAL]);
@@ -284,6 +285,10 @@ class ErrorHandlerTest extends TestCase
 
     public function testHandleUserError()
     {
+        if (\PHP_VERSION_ID >= 70400) {
+            $this->markTestSkipped('PHP 7.4 allows __toString to throw exceptions');
+        }
+
         try {
             $handler = ErrorHandler::register();
             $handler->throwAt(0, true);
@@ -331,12 +336,11 @@ class ErrorHandlerTest extends TestCase
     public function testHandleException()
     {
         try {
+            $logger = $this->getMockBuilder('Psr\Log\LoggerInterface')->getMock();
             $handler = ErrorHandler::register();
 
             $exception = new \Exception('foo');
 
-            $logger = $this->getMockBuilder('Psr\Log\LoggerInterface')->getMock();
-
             $logArgCheck = function ($level, $message, $context) {
                 $this->assertSame('Uncaught Exception: foo', $message);
                 $this->assertArrayHasKey('exception', $context);
@@ -442,6 +446,7 @@ class ErrorHandlerTest extends TestCase
     public function testHandleFatalError()
     {
         try {
+            $logger = $this->getMockBuilder('Psr\Log\LoggerInterface')->getMock();
             $handler = ErrorHandler::register();
 
             $error = [
@@ -451,8 +456,6 @@ class ErrorHandlerTest extends TestCase
                 'line' => 123,
             ];
 
-            $logger = $this->getMockBuilder('Psr\Log\LoggerInterface')->getMock();
-
             $logArgCheck = function ($level, $message, $context) {
                 $this->assertEquals('Fatal Parse Error: foo', $message);
                 $this->assertArrayHasKey('exception', $context);
@@ -494,11 +497,9 @@ class ErrorHandlerTest extends TestCase
         $this->assertStringStartsWith("Attempted to load class \"IReallyReallyDoNotExistAnywhereInTheRepositoryISwear\" from the global namespace.\nDid you forget a \"use\" statement", $args[0]->getMessage());
     }
 
-    /**
-     * @expectedException \Exception
-     */
     public function testCustomExceptionHandler()
     {
+        $this->expectException('Exception');
         $handler = new ErrorHandler();
         $handler->setExceptionHandler(function ($e) use ($handler) {
             $handler->handleException($e);

Tests/Exception/FlattenExceptionTest.php

@@ -30,6 +30,9 @@ use Symfony\Component\HttpKernel\Exception\TooManyRequestsHttpException;
 use Symfony\Component\HttpKernel\Exception\UnauthorizedHttpException;
 use Symfony\Component\HttpKernel\Exception\UnsupportedMediaTypeHttpException;
 
+/**
+ * @group legacy
+ */
 class FlattenExceptionTest extends TestCase
 {
     public function testStatusCode()
@@ -237,6 +240,10 @@ class FlattenExceptionTest extends TestCase
 
     public function testArguments()
     {
+        if (\PHP_VERSION_ID >= 70400) {
+            $this->markTestSkipped('PHP 7.4 removes arguments from exception traces.');
+        }
+
         $dh = opendir(__DIR__);
         $fh = tmpfile();
 
@@ -294,22 +301,30 @@ class FlattenExceptionTest extends TestCase
 
         // assertEquals() does not like NAN values.
         $this->assertEquals($array[$i][0], 'float');
-        $this->assertTrue(is_nan($array[$i++][1]));
+        $this->assertNan($array[$i][1]);
     }
 
     public function testRecursionInArguments()
     {
+        if (\PHP_VERSION_ID >= 70400) {
+            $this->markTestSkipped('PHP 7.4 removes arguments from exception traces.');
+        }
+
         $a = null;
         $a = ['foo', [2, &$a]];
         $exception = $this->createException($a);
 
         $flattened = FlattenException::create($exception);
         $trace = $flattened->getTrace();
-        $this->assertContains('*DEEP NESTED ARRAY*', serialize($trace));
+        $this->assertStringContainsString('*DEEP NESTED ARRAY*', serialize($trace));
     }
 
     public function testTooBigArray()
     {
+        if (\PHP_VERSION_ID >= 70400) {
+            $this->markTestSkipped('PHP 7.4 removes arguments from exception traces.');
+        }
+
         $a = [];
         for ($i = 0; $i < 20; ++$i) {
             for ($j = 0; $j < 50; ++$j) {
@@ -329,8 +344,8 @@ class FlattenExceptionTest extends TestCase
 
         $serializeTrace = serialize($trace);
 
-        $this->assertContains('*SKIPPED over 10000 entries*', $serializeTrace);
-        $this->assertNotContains('*value1*', $serializeTrace);
+        $this->assertStringContainsString('*SKIPPED over 10000 entries*', $serializeTrace);
+        $this->assertStringNotContainsString('*value1*', $serializeTrace);
     }
 
     public function testAnonymousClass()

Tests/ExceptionHandlerTest.php

@@ -19,18 +19,24 @@ use Symfony\Component\HttpKernel\Exception\NotFoundHttpException;
 
 require_once __DIR__.'/HeaderMock.php';
 
+/**
+ * @group legacy
+ */
 class ExceptionHandlerTest extends TestCase
 {
-    protected function setUp()
+    protected function setUp(): void
     {
         testHeader();
     }
 
-    protected function tearDown()
+    protected function tearDown(): void
     {
         testHeader();
     }
 
+    /**
+     * @group legacy
+     */
     public function testDebug()
     {
         $handler = new ExceptionHandler(false);
@@ -39,8 +45,8 @@ class ExceptionHandlerTest extends TestCase
         $handler->sendPhpResponse(new \RuntimeException('Foo'));
         $response = ob_get_clean();
 
-        $this->assertContains('Whoops, looks like something went wrong.', $response);
-        $this->assertNotContains('<div class="trace trace-as-html">', $response);
+        $this->assertStringContainsString('Whoops, looks like something went wrong.', $response);
+        $this->assertStringNotContainsString('<div class="trace trace-as-html">', $response);
 
         $handler = new ExceptionHandler(true);
 
@@ -48,8 +54,8 @@ class ExceptionHandlerTest extends TestCase
         $handler->sendPhpResponse(new \RuntimeException('Foo'));
         $response = ob_get_clean();
 
-        $this->assertContains('<h1 class="break-long-words exception-message">Foo</h1>', $response);
-        $this->assertContains('<div class="trace trace-as-html">', $response);
+        $this->assertStringContainsString('<h1 class="break-long-words exception-message">Foo</h1>', $response);
+        $this->assertStringContainsString('<div class="trace trace-as-html">', $response);
 
         // taken from https://www.owasp.org/index.php/Cross-site_Scripting_(XSS)
         $htmlWithXss = '<body onload=alert(\'test1\')> <b onmouseover=alert(\'Wufff!\')>click me!</b> <img src="j&#X41vascript:alert(\'test2\')"> <meta http-equiv="refresh"
@@ -58,7 +64,7 @@ content="0;url=data:text/html;base64,PHNjcmlwdD5hbGVydCgndGVzdDMnKTwvc2NyaXB0Pg"
         $handler->sendPhpResponse(new \RuntimeException($htmlWithXss));
         $response = ob_get_clean();
 
-        $this->assertContains(sprintf('<h1 class="break-long-words exception-message">%s</h1>', htmlspecialchars($htmlWithXss, ENT_COMPAT | ENT_SUBSTITUTE, 'UTF-8')), $response);
+        $this->assertStringContainsString(sprintf('<h1 class="break-long-words exception-message">%s</h1>', htmlspecialchars($htmlWithXss, ENT_COMPAT | ENT_SUBSTITUTE, 'UTF-8')), $response);
     }
 
     public function testStatusCode()
@@ -69,7 +75,7 @@ content="0;url=data:text/html;base64,PHNjcmlwdD5hbGVydCgndGVzdDMnKTwvc2NyaXB0Pg"
         $handler->sendPhpResponse(new NotFoundHttpException('Foo'));
         $response = ob_get_clean();
 
-        $this->assertContains('Sorry, the page you are looking for could not be found.', $response);
+        $this->assertStringContainsString('Sorry, the page you are looking for could not be found.', $response);
 
         $expectedHeaders = [
             ['HTTP/1.0 404', true, null],
@@ -85,7 +91,7 @@ content="0;url=data:text/html;base64,PHNjcmlwdD5hbGVydCgndGVzdDMnKTwvc2NyaXB0Pg"
 
         ob_start();
         $handler->sendPhpResponse(new MethodNotAllowedHttpException(['POST']));
-        $response = ob_get_clean();
+        ob_get_clean();
 
         $expectedHeaders = [
             ['HTTP/1.0 405', true, null],
@@ -108,35 +114,65 @@ content="0;url=data:text/html;base64,PHNjcmlwdD5hbGVydCgndGVzdDMnKTwvc2NyaXB0Pg"
 
     public function testHandle()
     {
-        $exception = new \Exception('foo');
+        $handler = new ExceptionHandler(true);
+        ob_start();
 
-        $handler = $this->getMockBuilder('Symfony\Component\Debug\ExceptionHandler')->setMethods(['sendPhpResponse'])->getMock();
-        $handler
-            ->expects($this->exactly(2))
-            ->method('sendPhpResponse');
+        $handler->handle(new \Exception('foo'));
 
-        $handler->handle($exception);
+        $this->assertThatTheExceptionWasOutput(ob_get_clean(), \Exception::class, 'Exception', 'foo');
+    }
 
-        $handler->setHandler(function ($e) use ($exception) {
-            $this->assertSame($exception, $e);
+    public function testHandleWithACustomHandlerThatOutputsSomething()
+    {
+        $handler = new ExceptionHandler(true);
+        ob_start();
+        $handler->setHandler(function () {
+            echo 'ccc';
         });
 
-        $handler->handle($exception);
+        $handler->handle(new \Exception());
+        ob_end_flush(); // Necessary because of this PHP bug : https://bugs.php.net/76563
+        $this->assertSame('ccc', ob_get_clean());
+    }
+
+    public function testHandleWithACustomHandlerThatOutputsNothing()
+    {
+        $handler = new ExceptionHandler(true);
+        $handler->setHandler(function () {});
+
+        $handler->handle(new \Exception('ccc'));
+
+        $this->assertThatTheExceptionWasOutput(ob_get_clean(), \Exception::class, 'Exception', 'ccc');
+    }
+
+    public function testHandleWithACustomHandlerThatFails()
+    {
+        $handler = new ExceptionHandler(true);
+        $handler->setHandler(function () {
+            throw new \RuntimeException();
+        });
+
+        $handler->handle(new \Exception('ccc'));
+
+        $this->assertThatTheExceptionWasOutput(ob_get_clean(), \Exception::class, 'Exception', 'ccc');
     }
 
     public function testHandleOutOfMemoryException()
     {
-        $exception = new OutOfMemoryException('foo', 0, E_ERROR, __FILE__, __LINE__);
-
-        $handler = $this->getMockBuilder('Symfony\Component\Debug\ExceptionHandler')->setMethods(['sendPhpResponse'])->getMock();
-        $handler
-            ->expects($this->once())
-            ->method('sendPhpResponse');
-
-        $handler->setHandler(function ($e) {
+        $handler = new ExceptionHandler(true);
+        ob_start();
+        $handler->setHandler(function () {
             $this->fail('OutOfMemoryException should bypass the handler');
         });
 
-        $handler->handle($exception);
+        $handler->handle(new OutOfMemoryException('foo', 0, E_ERROR, __FILE__, __LINE__));
+
+        $this->assertThatTheExceptionWasOutput(ob_get_clean(), OutOfMemoryException::class, 'OutOfMemoryException', 'foo');
+    }
+
+    private function assertThatTheExceptionWasOutput($content, $expectedClass, $expectedTitle, $expectedMessage)
+    {
+        $this->assertStringContainsString(sprintf('<span class="exception_title"><abbr title="%s">%s</abbr></span>', $expectedClass, $expectedTitle), $content);
+        $this->assertStringContainsString(sprintf('<p class="break-long-words trace-message">%s</p>', $expectedMessage), $content);
     }
 }

Tests/FatalErrorHandler/ClassNotFoundFatalErrorHandlerTest.php

@@ -17,9 +17,12 @@ use Symfony\Component\Debug\DebugClassLoader;
 use Symfony\Component\Debug\Exception\FatalErrorException;
 use Symfony\Component\Debug\FatalErrorHandler\ClassNotFoundFatalErrorHandler;
 
+/**
+ * @group legacy
+ */
 class ClassNotFoundFatalErrorHandlerTest extends TestCase
 {
-    public static function setUpBeforeClass()
+    public static function setUpBeforeClass(): void
     {
         foreach (spl_autoload_functions() as $function) {
             if (!\is_array($function)) {
@@ -32,7 +35,7 @@ class ClassNotFoundFatalErrorHandlerTest extends TestCase
             }
 
             if ($function[0] instanceof ComposerClassLoader) {
-                $function[0]->add('Symfony_Component_Debug_Tests_Fixtures', \dirname(\dirname(\dirname(\dirname(\dirname(__DIR__))))));
+                $function[0]->add('Symfony_Component_Debug_Tests_Fixtures', \dirname(__DIR__, 5));
                 break;
             }
         }
@@ -71,6 +74,7 @@ class ClassNotFoundFatalErrorHandlerTest extends TestCase
     {
         $autoloader = new ComposerClassLoader();
         $autoloader->add('Symfony\Component\Debug\Exception\\', realpath(__DIR__.'/../../Exception'));
+        $autoloader->add('Symfony_Component_Debug_Tests_Fixtures', realpath(__DIR__.'/../../Tests/Fixtures'));
 
         $debugClassLoader = new DebugClassLoader([$autoloader, 'loadClass']);
 
@@ -101,6 +105,7 @@ class ClassNotFoundFatalErrorHandlerTest extends TestCase
                     'message' => 'Class \'UndefinedFunctionException\' not found',
                 ],
                 "Attempted to load class \"UndefinedFunctionException\" from the global namespace.\nDid you forget a \"use\" statement for \"Symfony\Component\Debug\Exception\UndefinedFunctionException\"?",
+                [$debugClassLoader, 'loadClass'],
             ],
             [
                 [
@@ -110,6 +115,7 @@ class ClassNotFoundFatalErrorHandlerTest extends TestCase
                     'message' => 'Class \'PEARClass\' not found',
                 ],
                 "Attempted to load class \"PEARClass\" from the global namespace.\nDid you forget a \"use\" statement for \"Symfony_Component_Debug_Tests_Fixtures_PEARClass\"?",
+                [$debugClassLoader, 'loadClass'],
             ],
             [
                 [
@@ -119,6 +125,7 @@ class ClassNotFoundFatalErrorHandlerTest extends TestCase
                     'message' => 'Class \'Foo\\Bar\\UndefinedFunctionException\' not found',
                 ],
                 "Attempted to load class \"UndefinedFunctionException\" from namespace \"Foo\Bar\".\nDid you forget a \"use\" statement for \"Symfony\Component\Debug\Exception\UndefinedFunctionException\"?",
+                [$debugClassLoader, 'loadClass'],
             ],
             [
                 [

Tests/FatalErrorHandler/UndefinedFunctionFatalErrorHandlerTest.php

@@ -15,6 +15,9 @@ use PHPUnit\Framework\TestCase;
 use Symfony\Component\Debug\Exception\FatalErrorException;
 use Symfony\Component\Debug\FatalErrorHandler\UndefinedFunctionFatalErrorHandler;
 
+/**
+ * @group legacy
+ */
 class UndefinedFunctionFatalErrorHandlerTest extends TestCase
 {
     /**

Tests/FatalErrorHandler/UndefinedMethodFatalErrorHandlerTest.php

@@ -15,6 +15,9 @@ use PHPUnit\Framework\TestCase;
 use Symfony\Component\Debug\Exception\FatalErrorException;
 use Symfony\Component\Debug\FatalErrorHandler\UndefinedMethodFatalErrorHandler;
 
+/**
+ * @group legacy
+ */
 class UndefinedMethodFatalErrorHandlerTest extends TestCase
 {
     /**

Tests/Fixtures/FinalClasses.php

@@ -41,7 +41,6 @@ class FinalClass4
 /**
  * @author John Doe
  *
- *
  * @final multiline
  * comment
  */

Tests/Fixtures/LoggerThatSetAnErrorHandler.php

@@ -6,7 +6,7 @@ use Symfony\Component\Debug\BufferingLogger;
 
 class LoggerThatSetAnErrorHandler extends BufferingLogger
 {
-    public function log($level, $message, array $context = [])
+    public function log($level, $message, array $context = []): void
     {
         set_error_handler('is_string');
         parent::log($level, $message, $context);

Tests/MockExceptionHandler.php

@@ -1,24 +0,0 @@
-<?php
-
-/*
- * This file is part of the Symfony package.
- *
- * (c) Fabien Potencier <fabien@symfony.com>
- *
- * For the full copyright and license information, please view the LICENSE
- * file that was distributed with this source code.
- */
-
-namespace Symfony\Component\Debug\Tests;
-
-use Symfony\Component\Debug\ExceptionHandler;
-
-class MockExceptionHandler extends ExceptionHandler
-{
-    public $e;
-
-    public function handle(\Exception $e)
-    {
-        $this->e = $e;
-    }
-}

Tests/phpt/debug_class_loader.phpt

@@ -23,5 +23,6 @@ class_exists(ExtendedFinalMethod::class);
 
 ?>
 --EXPECTF--
+%A
 The "Symfony\Component\Debug\Tests\Fixtures\FinalMethod::finalMethod()" method is considered final. It may change without further notice as of its next major version. You should not extend it from "Symfony\Component\Debug\Tests\Fixtures\ExtendedFinalMethod".
 The "Symfony\Component\Debug\Tests\Fixtures\FinalMethod::finalMethod2()" method is considered final. It may change without further notice as of its next major version. You should not extend it from "Symfony\Component\Debug\Tests\Fixtures\ExtendedFinalMethod".

Tests/phpt/decorate_exception_hander.phpt

@@ -26,6 +26,7 @@ if (true) {
 
 ?>
 --EXPECTF--
+%A
 object(Symfony\Component\Debug\Exception\ClassNotFoundException)#%d (8) {
   ["message":protected]=>
   string(131) "Attempted to load class "missing" from namespace "Symfony\Component\Debug".

Tests/phpt/fatal_with_nested_handlers.phpt

@@ -35,6 +35,7 @@ array(1) {
   [0]=>
   string(37) "Error and exception handlers do match"
 }
+%A
 object(Symfony\Component\Debug\Exception\FatalErrorException)#%d (%d) {
   ["message":protected]=>
   string(179) "Error: Class Symfony\Component\Debug\Broken contains 1 abstract method and must therefore be declared abstract or implement the remaining methods (JsonSerializable::jsonSerialize)"

composer.json

@@ -23,7 +23,7 @@
         "symfony/http-kernel": "<3.4"
     },
     "require-dev": {
-        "symfony/http-kernel": "~3.4|~4.0"
+        "symfony/http-kernel": "^3.4|^4.0|^5.0"
     },
     "autoload": {
         "psr-4": { "Symfony\\Component\\Debug\\": "" },
@@ -34,7 +34,7 @@
     "minimum-stability": "dev",
     "extra": {
         "branch-alias": {
-            "dev-master": "4.3-dev"
+            "dev-master": "4.4-dev"
         }
     }
 }