Merge branch '2.8' into 3.4

* 2.8: Add note about changed form processing when using PUT requests The debug class loader is always loaded by Debug::enable(). [Intl] Update ICU data to 62.1
The debug class loader is always loaded by Debug::enable().
2026-03-25 09:42:20 +01:00 · 2018-06-25 13:10:40 +02:00 · 2018-06-22 17:01:26 +02:00 · 2018-06-08 11:38:38 +02:00 · 2018-06-06 10:34:52 +02:00 · 2018-05-16 16:03:39 +02:00
42 changed files with 1175 additions and 382 deletions
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,6 +1,23 @@
 CHANGELOG
 =========

+3.4.0
+-----
+
+* deprecated `ErrorHandler::stackErrors()` and `ErrorHandler::unstackErrors()`
+
+3.3.0
+-----
+
+* deprecated the `ContextErrorException` class: use \ErrorException directly now
+
+3.2.0
+-----
+
+* `FlattenException::getTrace()` now returns additional type descriptions
+  `integer` and `float`.
+
+
 3.0.0
 -----

--- a/Debug.php
+++ b/Debug.php
@@ -23,10 +23,7 @@ class Debug
    /**
     * Enables the debug tools.
     *
-     * This method registers an error handler and an exception handler.
-     *
-     * If the Symfony ClassLoader component is available, a special
-     * class loader is also registered.
+     * This method registers an error handler, an exception handler and a special class loader.
     *
     * @param int  $errorReportingLevel The level of error reporting you want
     * @param bool $displayErrors       Whether to display errors (for development) or just log them (for production)
@@ -45,7 +42,7 @@ class Debug
            error_reporting(E_ALL);
        }

-        if ('cli' !== PHP_SAPI) {
+        if (!\in_array(PHP_SAPI, array('cli', 'phpdbg'), true)) {
            ini_set('display_errors', 0);
            ExceptionHandler::register();
        } elseif ($displayErrors && (!ini_get('log_errors') || ini_get('error_log'))) {
--- a/DebugClassLoader.php
+++ b/DebugClassLoader.php
@@ -26,16 +26,17 @@ class DebugClassLoader
 {
    private $classLoader;
    private $isFinder;
+    private $loaded = array();
    private static $caseCheck;
+    private static $checkedClasses = array();
+    private static $final = array();
+    private static $finalMethods = array();
    private static $deprecated = array();
-    private static $php7Reserved = array('int', 'float', 'bool', 'string', 'true', 'false', 'null');
+    private static $internal = array();
+    private static $internalMethods = array();
+    private static $php7Reserved = array('int' => 1, 'float' => 1, 'bool' => 1, 'string' => 1, 'true' => 1, 'false' => 1, 'null' => 1);
    private static $darwinCache = array('/' => array('/', array()));

-    /**
-     * Constructor.
-     *
-     * @param callable $classLoader A class loader
-     */
    public function __construct(callable $classLoader)
    {
        $this->classLoader = $classLoader;
@@ -134,83 +135,152 @@ class DebugClassLoader
     */
    public function loadClass($class)
    {
-        ErrorHandler::stackErrors();
+        $e = error_reporting(error_reporting() | E_PARSE | E_ERROR | E_CORE_ERROR | E_COMPILE_ERROR);

        try {
-            if ($this->isFinder) {
-                if ($file = $this->classLoader[0]->findFile($class)) {
-                    require_once $file;
+            if ($this->isFinder && !isset($this->loaded[$class])) {
+                $this->loaded[$class] = true;
+                if ($file = $this->classLoader[0]->findFile($class) ?: false) {
+                    $wasCached = \function_exists('opcache_is_script_cached') && @opcache_is_script_cached($file);
+
+                    require $file;
+
+                    if ($wasCached) {
+                        return;
+                    }
                }
            } else {
                call_user_func($this->classLoader, $class);
                $file = false;
            }
        } finally {
-            ErrorHandler::unstackErrors();
+            error_reporting($e);
        }

-        $exists = class_exists($class, false) || interface_exists($class, false) || trait_exists($class, false);
+        $this->checkClass($class, $file);
+    }

-        if ('\\' === $class[0]) {
+    private function checkClass($class, $file = null)
+    {
+        $exists = null === $file || \class_exists($class, false) || \interface_exists($class, false) || \trait_exists($class, false);
+
+        if (null !== $file && $class && '\\' === $class[0]) {
            $class = substr($class, 1);
        }

        if ($exists) {
+            if (isset(self::$checkedClasses[$class])) {
+                return;
+            }
+            self::$checkedClasses[$class] = true;
+
            $refl = new \ReflectionClass($class);
+            if (null === $file && $refl->isInternal()) {
+                return;
+            }
            $name = $refl->getName();

-            if ($name !== $class && 0 === strcasecmp($name, $class)) {
-                throw new \RuntimeException(sprintf('Case mismatch between loaded and declared class names: %s vs %s', $class, $name));
+            if ($name !== $class && 0 === \strcasecmp($name, $class)) {
+                throw new \RuntimeException(sprintf('Case mismatch between loaded and declared class names: "%s" vs "%s".', $class, $name));
            }

-            if (in_array(strtolower($refl->getShortName()), self::$php7Reserved)) {
-                @trigger_error(sprintf('%s uses a reserved class name (%s) that will break on PHP 7 and higher', $name, $refl->getShortName()), E_USER_DEPRECATED);
-            } elseif (preg_match('#\n \* @deprecated (.*?)\r?\n \*(?: @|/$)#s', $refl->getDocComment(), $notice)) {
-                self::$deprecated[$name] = preg_replace('#\s*\r?\n \* +#', ' ', $notice[1]);
+            // Don't trigger deprecations for classes in the same vendor
+            if (2 > $len = 1 + (\strpos($name, '\\') ?: \strpos($name, '_'))) {
+                $len = 0;
+                $ns = '';
            } else {
-                if (2 > $len = 1 + (strpos($name, '\\', 1 + strpos($name, '\\')) ?: strpos($name, '_'))) {
-                    $len = 0;
-                    $ns = '';
-                } else {
-                    switch ($ns = substr($name, 0, $len)) {
-                        case 'Symfony\Bridge\\':
-                        case 'Symfony\Bundle\\':
-                        case 'Symfony\Component\\':
-                            $ns = 'Symfony\\';
-                            $len = strlen($ns);
-                            break;
+                $ns = \substr($name, 0, $len);
+            }
+
+            // Detect annotations on the class
+            if (false !== $doc = $refl->getDocComment()) {
+                foreach (array('final', 'deprecated', 'internal') as $annotation) {
+                    if (false !== \strpos($doc, $annotation) && preg_match('#\n \* @'.$annotation.'(?:( .+?)\.?)?\r?\n \*(?: @|/$)#s', $doc, $notice)) {
+                        self::${$annotation}[$name] = isset($notice[1]) ? preg_replace('#\s*\r?\n \* +#', ' ', $notice[1]) : '';
                    }
                }
-                $parent = get_parent_class($class);
+            }

-                if (!$parent || strncmp($ns, $parent, $len)) {
-                    if ($parent && isset(self::$deprecated[$parent]) && strncmp($ns, $parent, $len)) {
-                        @trigger_error(sprintf('The %s class extends %s that is deprecated %s', $name, $parent, self::$deprecated[$parent]), E_USER_DEPRECATED);
+            $parentAndTraits = \class_uses($name, false);
+            if ($parent = \get_parent_class($class)) {
+                $parentAndTraits[] = $parent;
+
+                if (!isset(self::$checkedClasses[$parent])) {
+                    $this->checkClass($parent);
+                }
+
+                if (isset(self::$final[$parent])) {
+                    @trigger_error(sprintf('The "%s" class is considered final%s. It may change without further notice as of its next major version. You should not extend it from "%s".', $parent, self::$final[$parent], $name), E_USER_DEPRECATED);
+                }
+            }
+
+            // Detect if the parent is annotated
+            foreach ($parentAndTraits + $this->getOwnInterfaces($name, $parent) as $use) {
+                if (!isset(self::$checkedClasses[$use])) {
+                    $this->checkClass($use);
+                }
+                if (isset(self::$deprecated[$use]) && \strncmp($ns, $use, $len)) {
+                    $type = class_exists($name, false) ? 'class' : (interface_exists($name, false) ? 'interface' : 'trait');
+                    $verb = class_exists($use, false) || interface_exists($name, false) ? 'extends' : (interface_exists($use, false) ? 'implements' : 'uses');
+
+                    @trigger_error(sprintf('The "%s" %s %s "%s" that is deprecated%s.', $name, $type, $verb, $use, self::$deprecated[$use]), E_USER_DEPRECATED);
+                }
+                if (isset(self::$internal[$use]) && \strncmp($ns, $use, $len)) {
+                    @trigger_error(sprintf('The "%s" %s is considered internal%s. It may change without further notice. You should not use it from "%s".', $use, class_exists($use, false) ? 'class' : (interface_exists($use, false) ? 'interface' : 'trait'), self::$internal[$use], $name), E_USER_DEPRECATED);
+                }
+            }
+
+            // Inherit @final and @internal annotations for methods
+            self::$finalMethods[$name] = array();
+            self::$internalMethods[$name] = array();
+            foreach ($parentAndTraits as $use) {
+                foreach (array('finalMethods', 'internalMethods') as $property) {
+                    if (isset(self::${$property}[$use])) {
+                        self::${$property}[$name] = self::${$property}[$name] ? self::${$property}[$use] + self::${$property}[$name] : self::${$property}[$use];
                    }
+                }
+            }

-                    $parentInterfaces = array();
-                    $deprecatedInterfaces = array();
-                    if ($parent) {
-                        foreach (class_implements($parent) as $interface) {
-                            $parentInterfaces[$interface] = 1;
-                        }
-                    }
+            $isClass = \class_exists($name, false);
+            foreach ($refl->getMethods(\ReflectionMethod::IS_PUBLIC | \ReflectionMethod::IS_PROTECTED) as $method) {
+                if ($method->class !== $name) {
+                    continue;
+                }

-                    foreach ($refl->getInterfaceNames() as $interface) {
-                        if (isset(self::$deprecated[$interface]) && strncmp($ns, $interface, $len)) {
-                            $deprecatedInterfaces[] = $interface;
-                        }
-                        foreach (class_implements($interface) as $interface) {
-                            $parentInterfaces[$interface] = 1;
-                        }
-                    }
+                // Method from a trait
+                if ($method->getFilename() !== $refl->getFileName()) {
+                    continue;
+                }

-                    foreach ($deprecatedInterfaces as $interface) {
-                        if (!isset($parentInterfaces[$interface])) {
-                            @trigger_error(sprintf('The %s %s %s that is deprecated %s', $name, $refl->isInterface() ? 'interface extends' : 'class implements', $interface, self::$deprecated[$interface]), E_USER_DEPRECATED);
+                if ($isClass && $parent && isset(self::$finalMethods[$parent][$method->name])) {
+                    list($declaringClass, $message) = self::$finalMethods[$parent][$method->name];
+                    @trigger_error(sprintf('The "%s::%s()" method is considered final%s. It may change without further notice as of its next major version. You should not extend it from "%s".', $declaringClass, $method->name, $message, $name), E_USER_DEPRECATED);
+                }
+
+                foreach ($parentAndTraits as $use) {
+                    if (isset(self::$internalMethods[$use][$method->name])) {
+                        list($declaringClass, $message) = self::$internalMethods[$use][$method->name];
+                        if (\strncmp($ns, $declaringClass, $len)) {
+                            @trigger_error(sprintf('The "%s::%s()" method is considered internal%s. It may change without further notice. You should not extend it from "%s".', $declaringClass, $method->name, $message, $name), E_USER_DEPRECATED);
                        }
                    }
                }
+
+                // Detect method annotations
+                if (false === $doc = $method->getDocComment()) {
+                    continue;
+                }
+
+                foreach (array('final', 'internal') as $annotation) {
+                    if (false !== \strpos($doc, $annotation) && preg_match('#\n\s+\* @'.$annotation.'(?:( .+?)\.?)?\r?\n\s+\*(?: @|/$)#s', $doc, $notice)) {
+                        $message = isset($notice[1]) ? preg_replace('#\s*\r?\n \* +#', ' ', $notice[1]) : '';
+                        self::${$annotation.'Methods'}[$name][$method->name] = array($name, $message);
+                    }
+                }
+            }
+
+            if (isset(self::$php7Reserved[\strtolower($refl->getShortName())])) {
+                @trigger_error(sprintf('The "%s" class uses the reserved name "%s", it will break on PHP 7 and higher', $name, $refl->getShortName()), E_USER_DEPRECATED);
            }
        }

@@ -304,11 +374,36 @@ class DebugClassLoader
                if (0 === substr_compare($real, $tail, -$tailLen, $tailLen, true)
                  && 0 !== substr_compare($real, $tail, -$tailLen, $tailLen, false)
                ) {
-                    throw new \RuntimeException(sprintf('Case mismatch between class and real file names: %s vs %s in %s', substr($tail, -$tailLen + 1), substr($real, -$tailLen + 1), substr($real, 0, -$tailLen + 1)));
+                    throw new \RuntimeException(sprintf('Case mismatch between class and real file names: "%s" vs "%s" in "%s".', substr($tail, -$tailLen + 1), substr($real, -$tailLen + 1), substr($real, 0, -$tailLen + 1)));
                }
            }
-
-            return true;
        }
    }
+
+    /**
+     * `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)
+    {
+        $ownInterfaces = class_implements($class, false);
+
+        if ($parent) {
+            foreach (class_implements($parent, false) as $interface) {
+                unset($ownInterfaces[$interface]);
+            }
+        }
+
+        foreach ($ownInterfaces as $interface) {
+            foreach (class_implements($interface) as $interface) {
+                unset($ownInterfaces[$interface]);
+            }
+        }
+
+        return $ownInterfaces;
+    }
 }
--- a/ErrorHandler.php
+++ b/ErrorHandler.php
@@ -17,6 +17,7 @@ use Symfony\Component\Debug\Exception\ContextErrorException;
 use Symfony\Component\Debug\Exception\FatalErrorException;
 use Symfony\Component\Debug\Exception\FatalThrowableError;
 use Symfony\Component\Debug\Exception\OutOfMemoryException;
+use Symfony\Component\Debug\Exception\SilencedErrorContext;
 use Symfony\Component\Debug\FatalErrorHandler\UndefinedFunctionFatalErrorHandler;
 use Symfony\Component\Debug\FatalErrorHandler\UndefinedMethodFatalErrorHandler;
 use Symfony\Component\Debug\FatalErrorHandler\ClassNotFoundFatalErrorHandler;
@@ -29,7 +30,7 @@ use Symfony\Component\Debug\FatalErrorHandler\FatalErrorHandlerInterface;
 * - thrownErrors: errors thrown as \ErrorException
 * - loggedErrors: logged errors, when not @-silenced
 * - scopedErrors: errors thrown or logged with their local context
- * - tracedErrors: errors logged with their stack trace, only once for repeated errors
+ * - tracedErrors: errors logged with their stack trace
 * - screamedErrors: never @-silenced errors
 *
 * Each error level can be logged by a dedicated PSR-3 logger object.
@@ -43,6 +44,7 @@ use Symfony\Component\Debug\FatalErrorHandler\FatalErrorHandlerInterface;
 * can see them and weight them as more important to fix than others of the same level.
 *
 * @author Nicolas Grekas <p@tchwork.com>
+ * @author Grégoire Pineau <lyrixx@lyrixx.info>
 */
 class ErrorHandler
 {
@@ -87,8 +89,8 @@ class ErrorHandler
    private $tracedErrors = 0x77FB; // E_ALL - E_STRICT - E_PARSE
    private $screamedErrors = 0x55; // E_ERROR + E_CORE_ERROR + E_COMPILE_ERROR + E_PARSE
    private $loggedErrors = 0;
+    private $traceReflector;

-    private $loggedTraces = array();
    private $isRecursive = 0;
    private $isRoot = false;
    private $exceptionHandler;
@@ -98,6 +100,9 @@ class ErrorHandler
    private static $stackedErrors = array();
    private static $stackedErrorLevels = array();
    private static $toStringException = null;
+    private static $silencedErrorCache = array();
+    private static $silencedErrorCount = 0;
+    private static $exitCode = 0;

    /**
     * Registers the error handler.
@@ -129,10 +134,24 @@ class ErrorHandler
            $handler = $prev[0];
            $replace = false;
        }
-        if ($replace || !$prev) {
-            $handler->setExceptionHandler(set_exception_handler(array($handler, 'handleException')));
-        } else {
+        if (!$replace && $prev) {
            restore_error_handler();
+            $handlerIsRegistered = is_array($prev) && $handler === $prev[0];
+        } else {
+            $handlerIsRegistered = true;
+        }
+        if (is_array($prev = set_exception_handler(array($handler, 'handleException'))) && $prev[0] instanceof self) {
+            restore_exception_handler();
+            if (!$handlerIsRegistered) {
+                $handler = $prev[0];
+            } elseif ($handler !== $prev[0] && $replace) {
+                set_exception_handler(array($handler, 'handleException'));
+                $p = $prev[0]->setExceptionHandler(null);
+                $handler->setExceptionHandler($p);
+                $prev[0]->setExceptionHandler($p);
+            }
+        } else {
+            $handler->setExceptionHandler($prev);
        }

        $handler->throwAt(E_ALL & $handler->thrownErrors, true);
@@ -146,6 +165,8 @@ class ErrorHandler
            $this->bootstrappingLogger = $bootstrappingLogger;
            $this->setDefaultLogger($bootstrappingLogger);
        }
+        $this->traceReflector = new \ReflectionProperty('Exception', 'trace');
+        $this->traceReflector->setAccessible(true);
    }

    /**
@@ -221,7 +242,7 @@ class ErrorHandler

        if ($flush) {
            foreach ($this->bootstrappingLogger->cleanLogs() as $log) {
-                $type = $log[2]['type'];
+                $type = $log[2]['exception'] instanceof \ErrorException ? $log[2]['exception']->getSeverity() : E_ERROR;
                if (!isset($flush[$type])) {
                    $this->bootstrappingLogger->log($log[0], $log[1], $log[2]);
                } elseif ($this->loggers[$type][0]) {
@@ -361,13 +382,17 @@ class ErrorHandler
     */
    public function handleError($type, $message, $file, $line)
    {
-        $level = error_reporting() | E_RECOVERABLE_ERROR | E_USER_ERROR | E_DEPRECATED | E_USER_DEPRECATED;
+        // Level is the current error reporting level to manage silent error.
+        $level = error_reporting();
+        $silenced = 0 === ($level & $type);
+        // Strong errors are not authorized to be silenced.
+        $level |= E_RECOVERABLE_ERROR | E_USER_ERROR | E_DEPRECATED | E_USER_DEPRECATED;
        $log = $this->loggedErrors & $type;
        $throw = $this->thrownErrors & $type & $level;
        $type &= $level | $this->screamedErrors;

        if (!$type || (!$log && !$throw)) {
-            return $type && $log;
+            return !$silenced && $type && $log;
        }
        $scope = $this->scopedErrors & $type;

@@ -394,20 +419,53 @@ class ErrorHandler
            return true;
        }

-        if ($throw) {
-            if (null !== self::$toStringException) {
-                $throw = self::$toStringException;
-                self::$toStringException = null;
-            } elseif ($scope && class_exists(ContextErrorException::class)) {
-                // Checking for class existence is a work around for https://bugs.php.net/42098
-                $throw = new ContextErrorException($this->levels[$type].': '.$message, 0, $type, $file, $line, $context);
+        $logMessage = $this->levels[$type].': '.$message;
+
+        if (null !== self::$toStringException) {
+            $errorAsException = self::$toStringException;
+            self::$toStringException = null;
+        } elseif (!$throw && !($type & $level)) {
+            if (!isset(self::$silencedErrorCache[$id = $file.':'.$line])) {
+                $lightTrace = $this->tracedErrors & $type ? $this->cleanTrace(debug_backtrace(DEBUG_BACKTRACE_IGNORE_ARGS, 3), $type, $file, $line, false) : array();
+                $errorAsException = new SilencedErrorContext($type, $file, $line, $lightTrace);
+            } elseif (isset(self::$silencedErrorCache[$id][$message])) {
+                $lightTrace = null;
+                $errorAsException = self::$silencedErrorCache[$id][$message];
+                ++$errorAsException->count;
            } else {
-                $throw = new \ErrorException($this->levels[$type].': '.$message, 0, $type, $file, $line);
+                $lightTrace = array();
+                $errorAsException = null;
            }

-            if (E_USER_ERROR & $type) {
-                $backtrace = $backtrace ?: $throw->getTrace();
+            if (100 < ++self::$silencedErrorCount) {
+                self::$silencedErrorCache = $lightTrace = array();
+                self::$silencedErrorCount = 1;
+            }
+            if ($errorAsException) {
+                self::$silencedErrorCache[$id][$message] = $errorAsException;
+            }
+            if (null === $lightTrace) {
+                return;
+            }
+        } else {
+            if ($scope) {
+                $errorAsException = new ContextErrorException($logMessage, 0, $type, $file, $line, $context);
+            } else {
+                $errorAsException = new \ErrorException($logMessage, 0, $type, $file, $line);
+            }

+            // Clean the trace by removing function arguments and the first frames added by the error handler itself.
+            if ($throw || $this->tracedErrors & $type) {
+                $backtrace = $backtrace ?: $errorAsException->getTrace();
+                $lightTrace = $this->cleanTrace($backtrace, $type, $file, $line, $throw);
+                $this->traceReflector->setValue($errorAsException, $lightTrace);
+            } else {
+                $this->traceReflector->setValue($errorAsException, array());
+            }
+        }
+
+        if ($throw) {
+            if (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']
@@ -426,7 +484,7 @@ class ErrorHandler
                            if (($e instanceof \Exception || $e instanceof \Throwable) && $e->__toString() === $message) {
                                if (1 === $i) {
                                    // On HHVM
-                                    $throw = $e;
+                                    $errorAsException = $e;
                                    break;
                                }
                                self::$toStringException = $e;
@@ -437,7 +495,7 @@ class ErrorHandler

                        if (1 < $i) {
                            // On PHP (not on HHVM), display the original error message instead of the default one.
-                            $this->handleException($throw);
+                            $this->handleException($errorAsException);

                            // Stop the process by giving back the error to the native handler.
                            return false;
@@ -446,53 +504,29 @@ class ErrorHandler
                }
            }

-            throw $throw;
-        }
-
-        // For duplicated errors, log the trace only once
-        $e = md5("{$type}/{$line}/{$file}\x00{$message}", true);
-        $trace = true;
-
-        if (!($this->tracedErrors & $type) || isset($this->loggedTraces[$e])) {
-            $trace = false;
-        } else {
-            $this->loggedTraces[$e] = 1;
-        }
-
-        $e = compact('type', 'file', 'line', 'level');
-
-        if ($type & $level) {
-            if ($scope) {
-                $e['scope_vars'] = $context;
-                if ($trace) {
-                    $e['stack'] = $backtrace ?: debug_backtrace(DEBUG_BACKTRACE_PROVIDE_OBJECT);
-                }
-            } elseif ($trace) {
-                if (null === $backtrace) {
-                    $e['stack'] = debug_backtrace(DEBUG_BACKTRACE_IGNORE_ARGS);
-                } else {
-                    foreach ($backtrace as &$frame) {
-                        unset($frame['args'], $frame);
-                    }
-                    $e['stack'] = $backtrace;
-                }
-            }
+            throw $errorAsException;
        }

        if ($this->isRecursive) {
            $log = 0;
        } elseif (self::$stackedErrorLevels) {
-            self::$stackedErrors[] = array($this->loggers[$type][0], ($type & $level) ? $this->loggers[$type][1] : LogLevel::DEBUG, $message, $e);
+            self::$stackedErrors[] = array(
+                $this->loggers[$type][0],
+                ($type & $level) ? $this->loggers[$type][1] : LogLevel::DEBUG,
+                $logMessage,
+                $errorAsException ? array('exception' => $errorAsException) : array(),
+            );
        } else {
            try {
                $this->isRecursive = true;
-                $this->loggers[$type][0]->log(($type & $level) ? $this->loggers[$type][1] : LogLevel::DEBUG, $message, $e);
+                $level = ($type & $level) ? $this->loggers[$type][1] : LogLevel::DEBUG;
+                $this->loggers[$type][0]->log($level, $logMessage, $errorAsException ? array('exception' => $errorAsException) : array());
            } finally {
                $this->isRecursive = false;
            }
        }

-        return $type && $log;
+        return !$silenced && $type && $log;
    }

    /**
@@ -505,42 +539,36 @@ class ErrorHandler
     */
    public function handleException($exception, array $error = null)
    {
+        if (null === $error) {
+            self::$exitCode = 255;
+        }
        if (!$exception instanceof \Exception) {
            $exception = new FatalThrowableError($exception);
        }
        $type = $exception instanceof FatalErrorException ? $exception->getSeverity() : E_ERROR;
+        $handlerException = null;

        if (($this->loggedErrors & $type) || $exception instanceof FatalThrowableError) {
-            $e = array(
-                'type' => $type,
-                'file' => $exception->getFile(),
-                'line' => $exception->getLine(),
-                'level' => error_reporting(),
-                'stack' => $exception->getTrace(),
-            );
            if ($exception instanceof FatalErrorException) {
                if ($exception instanceof FatalThrowableError) {
                    $error = array(
                        'type' => $type,
                        'message' => $message = $exception->getMessage(),
-                        'file' => $e['file'],
-                        'line' => $e['line'],
+                        'file' => $exception->getFile(),
+                        'line' => $exception->getLine(),
                    );
                } else {
                    $message = 'Fatal '.$exception->getMessage();
                }
            } elseif ($exception instanceof \ErrorException) {
                $message = 'Uncaught '.$exception->getMessage();
-                if ($exception instanceof ContextErrorException) {
-                    $e['context'] = $exception->getContext();
-                }
            } else {
                $message = 'Uncaught Exception: '.$exception->getMessage();
            }
        }
        if ($this->loggedErrors & $type) {
            try {
-                $this->loggers[$type][0]->log($this->loggers[$type][1], $message, $e);
+                $this->loggers[$type][0]->log($this->loggers[$type][1], $message, array('exception' => $exception));
            } catch (\Exception $handlerException) {
            } catch (\Throwable $handlerException) {
            }
@@ -553,18 +581,21 @@ class ErrorHandler
                }
            }
        }
-        if (empty($this->exceptionHandler)) {
-            throw $exception; // Give back $exception to the native handler
-        }
+        $exceptionHandler = $this->exceptionHandler;
+        $this->exceptionHandler = null;
        try {
-            call_user_func($this->exceptionHandler, $exception);
+            if (null !== $exceptionHandler) {
+                return \call_user_func($exceptionHandler, $exception);
+            }
+            $handlerException = $handlerException ?: $exception;
        } catch (\Exception $handlerException) {
        } catch (\Throwable $handlerException) {
        }
-        if (isset($handlerException)) {
-            $this->exceptionHandler = null;
-            $this->handleException($handlerException);
+        if ($exception === $handlerException) {
+            self::$reservedMemory = null; // Disable the fatal error handler
+            throw $exception; // Give back $exception to the native handler
        }
+        $this->handleException($handlerException);
    }

    /**
@@ -580,17 +611,41 @@ class ErrorHandler
            return;
        }

-        self::$reservedMemory = null;
+        $handler = self::$reservedMemory = null;
+        $handlers = array();
+        $previousHandler = null;
+        $sameHandlerLimit = 10;

-        $handler = set_error_handler('var_dump');
-        $handler = is_array($handler) ? $handler[0] : null;
-        restore_error_handler();
+        while (!is_array($handler) || !$handler[0] instanceof self) {
+            $handler = set_exception_handler('var_dump');
+            restore_exception_handler();

-        if (!$handler instanceof self) {
+            if (!$handler) {
+                break;
+            }
+            restore_exception_handler();
+
+            if ($handler !== $previousHandler) {
+                array_unshift($handlers, $handler);
+                $previousHandler = $handler;
+            } elseif (0 === --$sameHandlerLimit) {
+                $handler = null;
+                break;
+            }
+        }
+        foreach ($handlers as $h) {
+            set_exception_handler($h);
+        }
+        if (!$handler) {
            return;
        }
+        if ($handler !== $h) {
+            $handler[0]->setExceptionHandler($h);
+        }
+        $handler = $handler[0];
+        $handlers = array();

-        if (null === $error) {
+        if ($exit = null === $error) {
            $error = error_get_last();
        }

@@ -614,15 +669,21 @@ class ErrorHandler
            } else {
                $exception = new FatalErrorException($handler->levels[$error['type']].': '.$error['message'], 0, $error['type'], $error['file'], $error['line'], 2, true, $trace);
            }
-        } elseif (!isset($exception)) {
-            return;
        }

        try {
-            $handler->handleException($exception, $error);
+            if (isset($exception)) {
+                self::$exitCode = 255;
+                $handler->handleException($exception, $error);
+            }
        } catch (FatalErrorException $e) {
            // Ignore this re-throw
        }
+
+        if ($exit && self::$exitCode) {
+            $exitCode = self::$exitCode;
+            register_shutdown_function('register_shutdown_function', function () use ($exitCode) { exit($exitCode); });
+        }
    }

    /**
@@ -635,24 +696,32 @@ class ErrorHandler
     *
     * The most important feature of this is to prevent
     * autoloading until unstackErrors() is called.
+     *
+     * @deprecated since version 3.4, to be removed in 4.0.
     */
    public static function stackErrors()
    {
+        @trigger_error('Support for stacking errors is deprecated since Symfony 3.4 and will be removed in 4.0.', E_USER_DEPRECATED);
+
        self::$stackedErrorLevels[] = error_reporting(error_reporting() | E_PARSE | E_ERROR | E_CORE_ERROR | E_COMPILE_ERROR);
    }

    /**
     * Unstacks stacked errors and forwards to the logger.
+     *
+     * @deprecated since version 3.4, to be removed in 4.0.
     */
    public static function unstackErrors()
    {
+        @trigger_error('Support for unstacking errors is deprecated since Symfony 3.4 and will be removed in 4.0.', E_USER_DEPRECATED);
+
        $level = array_pop(self::$stackedErrorLevels);

        if (null !== $level) {
-            $e = error_reporting($level);
-            if ($e !== ($level | E_PARSE | E_ERROR | E_CORE_ERROR | E_COMPILE_ERROR)) {
+            $errorReportingLevel = error_reporting($level);
+            if ($errorReportingLevel !== ($level | E_PARSE | E_ERROR | E_CORE_ERROR | E_COMPILE_ERROR)) {
                // If the user changed the error level, do not overwrite it
-                error_reporting($e);
+                error_reporting($errorReportingLevel);
            }
        }

@@ -660,8 +729,8 @@ class ErrorHandler
            $errors = self::$stackedErrors;
            self::$stackedErrors = array();

-            foreach ($errors as $e) {
-                $e[0]->log($e[1], $e[2], $e[3]);
+            foreach ($errors as $error) {
+                $error[0]->log($error[1], $error[2], $error[3]);
            }
        }
    }
@@ -681,4 +750,23 @@ class ErrorHandler
            new ClassNotFoundFatalErrorHandler(),
        );
    }
+
+    private function cleanTrace($backtrace, $type, $file, $line, $throw)
+    {
+        $lightTrace = $backtrace;
+
+        for ($i = 0; isset($backtrace[$i]); ++$i) {
+            if (isset($backtrace[$i]['file'], $backtrace[$i]['line']) && $backtrace[$i]['line'] === $line && $backtrace[$i]['file'] === $file) {
+                $lightTrace = array_slice($lightTrace, 1 + $i);
+                break;
+            }
+        }
+        if (!($throw || $this->scopedErrors & $type)) {
+            for ($i = 0; isset($lightTrace[$i]); ++$i) {
+                unset($lightTrace[$i]['args'], $lightTrace[$i]['object']);
+            }
+        }
+
+        return $lightTrace;
+    }
 }
--- a/Exception/ClassNotFoundException.php
+++ b/Exception/ClassNotFoundException.php
@@ -26,6 +26,9 @@ class ClassNotFoundException extends FatalErrorException
            $previous->getSeverity(),
            $previous->getFile(),
            $previous->getLine(),
+            null,
+            true,
+            null,
            $previous->getPrevious()
        );
        $this->setTrace($previous->getTrace());
--- a/Exception/ContextErrorException.php
+++ b/Exception/ContextErrorException.php
@@ -15,6 +15,8 @@ namespace Symfony\Component\Debug\Exception;
 * Error Exception with Variable Context.
 *
 * @author Christian Sciberras <uuf6429@gmail.com>
+ *
+ * @deprecated since version 3.3. Instead, \ErrorException will be used directly in 4.0.
 */
 class ContextErrorException extends \ErrorException
 {
@@ -31,6 +33,8 @@ class ContextErrorException extends \ErrorException
     */
    public function getContext()
    {
+        @trigger_error(sprintf('The %s class is deprecated since Symfony 3.3 and will be removed in 4.0.', __CLASS__), E_USER_DEPRECATED);
+
        return $this->context;
    }
 }
--- a/Exception/FatalErrorException.php
+++ b/Exception/FatalErrorException.php
@@ -18,9 +18,9 @@ namespace Symfony\Component\Debug\Exception;
 */
 class FatalErrorException extends \ErrorException
 {
-    public function __construct($message, $code, $severity, $filename, $lineno, $traceOffset = null, $traceArgs = true, array $trace = null)
+    public function __construct($message, $code, $severity, $filename, $lineno, $traceOffset = null, $traceArgs = true, array $trace = null, $previous = null)
    {
-        parent::__construct($message, $code, $severity, $filename, $lineno);
+        parent::__construct($message, $code, $severity, $filename, $lineno, $previous);

        if (null !== $trace) {
            if (!$traceArgs) {
--- a/Exception/FatalThrowableError.php
+++ b/Exception/FatalThrowableError.php
@@ -36,7 +36,8 @@ class FatalThrowableError extends FatalErrorException
            $e->getCode(),
            $severity,
            $e->getFile(),
-            $e->getLine()
+            $e->getLine(),
+            $e->getPrevious()
        );

        $this->setTrace($e->getTrace());
--- a/Exception/FlattenException.php
+++ b/Exception/FlattenException.php
@@ -11,6 +11,7 @@

 namespace Symfony\Component\Debug\Exception;

+use Symfony\Component\HttpFoundation\Exception\RequestExceptionInterface;
 use Symfony\Component\HttpKernel\Exception\HttpExceptionInterface;

 /**
@@ -41,6 +42,8 @@ class FlattenException
        if ($exception instanceof HttpExceptionInterface) {
            $statusCode = $exception->getStatusCode();
            $headers = array_merge($headers, $exception->getHeaders());
+        } elseif ($exception instanceof RequestExceptionInterface) {
+            $statusCode = 400;
        }

        if (null === $statusCode) {
@@ -154,7 +157,7 @@ class FlattenException
        return $this->previous;
    }

-    public function setPrevious(FlattenException $previous)
+    public function setPrevious(self $previous)
    {
        $this->previous = $previous;
    }
@@ -237,6 +240,10 @@ class FlattenException
                $result[$key] = array('null', null);
            } elseif (is_bool($value)) {
                $result[$key] = array('boolean', $value);
+            } elseif (is_int($value)) {
+                $result[$key] = array('integer', $value);
+            } elseif (is_float($value)) {
+                $result[$key] = array('float', $value);
            } elseif (is_resource($value)) {
                $result[$key] = array('resource', get_resource_type($value));
            } else {
--- a/Exception/SilencedErrorContext.php
+++ b/Exception/SilencedErrorContext.php
@@ -0,0 +1,67 @@
+<?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\Exception;
+
+/**
+ * Data Object that represents a Silenced Error.
+ *
+ * @author Grégoire Pineau <lyrixx@lyrixx.info>
+ */
+class SilencedErrorContext implements \JsonSerializable
+{
+    public $count = 1;
+
+    private $severity;
+    private $file;
+    private $line;
+    private $trace;
+
+    public function __construct($severity, $file, $line, array $trace = array(), $count = 1)
+    {
+        $this->severity = $severity;
+        $this->file = $file;
+        $this->line = $line;
+        $this->trace = $trace;
+        $this->count = $count;
+    }
+
+    public function getSeverity()
+    {
+        return $this->severity;
+    }
+
+    public function getFile()
+    {
+        return $this->file;
+    }
+
+    public function getLine()
+    {
+        return $this->line;
+    }
+
+    public function getTrace()
+    {
+        return $this->trace;
+    }
+
+    public function JsonSerialize()
+    {
+        return array(
+            'severity' => $this->severity,
+            'file' => $this->file,
+            'line' => $this->line,
+            'trace' => $this->trace,
+            'count' => $this->count,
+        );
+    }
+}
--- a/Exception/UndefinedFunctionException.php
+++ b/Exception/UndefinedFunctionException.php
@@ -26,6 +26,9 @@ class UndefinedFunctionException extends FatalErrorException
            $previous->getSeverity(),
            $previous->getFile(),
            $previous->getLine(),
+            null,
+            true,
+            null,
            $previous->getPrevious()
        );
        $this->setTrace($previous->getTrace());
--- a/Exception/UndefinedMethodException.php
+++ b/Exception/UndefinedMethodException.php
@@ -26,6 +26,9 @@ class UndefinedMethodException extends FatalErrorException
            $previous->getSeverity(),
            $previous->getFile(),
            $previous->getLine(),
+            null,
+            true,
+            null,
            $previous->getPrevious()
        );
        $this->setTrace($previous->getTrace());
--- a/ExceptionHandler.php
+++ b/ExceptionHandler.php
--- a/2
+++ b/2
@@ -1,4 +1,4 @@
-Copyright (c) 2004-2017 Fabien Potencier
+Copyright (c) 2004-2018 Fabien Potencier

 Permission is hereby granted, free of charge, to any person obtaining a copy
 of this software and associated documentation files (the "Software"), to deal
--- a/Resources/ext/tests/001.phpt
+++ b/Resources/ext/tests/001.phpt
@@ -1,7 +1,9 @@
 --TEST--
 Test symfony_zval_info API
 --SKIPIF--
-<?php if (!extension_loaded('symfony_debug')) print 'skip'; ?>
+<?php if (!extension_loaded('symfony_debug')) {
+    echo 'skip';
+} ?>
 --FILE--
 <?php

--- a/Resources/ext/tests/002.phpt
+++ b/Resources/ext/tests/002.phpt
@@ -1,7 +1,9 @@
 --TEST--
 Test symfony_debug_backtrace in case of fatal error
 --SKIPIF--
-<?php if (!extension_loaded('symfony_debug')) print 'skip'; ?>
+<?php if (!extension_loaded('symfony_debug')) {
+    echo 'skip';
+} ?>
 --FILE--
 <?php

--- a/Resources/ext/tests/002_1.phpt
+++ b/Resources/ext/tests/002_1.phpt
@@ -1,7 +1,9 @@
 --TEST--
 Test symfony_debug_backtrace in case of non fatal error
 --SKIPIF--
-<?php if (!extension_loaded('symfony_debug')) print 'skip'; ?>
+<?php if (!extension_loaded('symfony_debug')) {
+    echo 'skip';
+} ?>
 --FILE--
 <?php

--- a/Resources/ext/tests/003.phpt
+++ b/Resources/ext/tests/003.phpt
@@ -1,7 +1,9 @@
 --TEST--
 Test ErrorHandler in case of fatal error
 --SKIPIF--
-<?php if (!extension_loaded('symfony_debug')) print 'skip'; ?>
+<?php if (!extension_loaded('symfony_debug')) {
+    echo 'skip';
+} ?>
 --FILE--
 <?php

--- a/Tests/DebugClassLoaderTest.php
+++ b/Tests/DebugClassLoaderTest.php
@@ -11,10 +11,11 @@

 namespace Symfony\Component\Debug\Tests;

+use PHPUnit\Framework\TestCase;
 use Symfony\Component\Debug\DebugClassLoader;
 use Symfony\Component\Debug\ErrorHandler;

-class DebugClassLoaderTest extends \PHPUnit_Framework_TestCase
+class DebugClassLoaderTest extends TestCase
 {
    /**
     * @var int Error reporting level before running tests
@@ -58,9 +59,26 @@ class DebugClassLoaderTest extends \PHPUnit_Framework_TestCase
        $this->fail('DebugClassLoader did not register');
    }

+    /**
+     * @expectedException \Exception
+     * @expectedExceptionMessage boo
+     */
+    public function testThrowingClass()
+    {
+        try {
+            class_exists(__NAMESPACE__.'\Fixtures\Throwing');
+            $this->fail('Exception expected');
+        } catch (\Exception $e) {
+            $this->assertSame('boo', $e->getMessage());
+        }
+
+        // the second call also should throw
+        class_exists(__NAMESPACE__.'\Fixtures\Throwing');
+    }
+
    public function testUnsilencing()
    {
-        if (PHP_VERSION_ID >= 70000) {
+        if (\PHP_VERSION_ID >= 70000) {
            $this->markTestSkipped('PHP7 throws exceptions, unsilencing is not required anymore.');
        }
        if (defined('HHVM_VERSION')) {
@@ -108,7 +126,7 @@ class DebugClassLoaderTest extends \PHPUnit_Framework_TestCase
        } catch (\ErrorException $exception) {
            // if an exception is thrown, the test passed
            $this->assertStringStartsWith(__FILE__, $exception->getFile());
-            if (PHP_VERSION_ID < 70000) {
+            if (\PHP_VERSION_ID < 70000) {
                $this->assertRegExp('/^Runtime Notice: Declaration/', $exception->getMessage());
                $this->assertEquals(E_STRICT, $exception->getSeverity());
            } else {
@@ -123,6 +141,7 @@ class DebugClassLoaderTest extends \PHPUnit_Framework_TestCase

    /**
     * @expectedException \RuntimeException
+     * @expectedExceptionMessage Case mismatch between loaded and declared class names
     */
    public function testNameCaseMismatch()
    {
@@ -144,6 +163,7 @@ class DebugClassLoaderTest extends \PHPUnit_Framework_TestCase

    /**
     * @expectedException \RuntimeException
+     * @expectedExceptionMessage Case mismatch between loaded and declared class names
     */
    public function testPsr4CaseMismatch()
    {
@@ -184,7 +204,7 @@ class DebugClassLoaderTest extends \PHPUnit_Framework_TestCase

        $xError = array(
            'type' => E_USER_DEPRECATED,
-            'message' => 'The Test\Symfony\Component\Debug\Tests\\'.$class.' class '.$type.' Symfony\Component\Debug\Tests\Fixtures\\'.$super.' that is deprecated but this is a test deprecation notice.',
+            'message' => 'The "Test\Symfony\Component\Debug\Tests\\'.$class.'" class '.$type.' "Symfony\Component\Debug\Tests\Fixtures\\'.$super.'" that is deprecated but this is a test deprecation notice.',
        );

        $this->assertSame($xError, $lastError);
@@ -244,7 +264,7 @@ class DebugClassLoaderTest extends \PHPUnit_Framework_TestCase

    public function testReservedForPhp7()
    {
-        if (PHP_VERSION_ID >= 70000) {
+        if (\PHP_VERSION_ID >= 70000) {
            $this->markTestSkipped('PHP7 already prevents using reserved names.');
        }

@@ -262,11 +282,91 @@ class DebugClassLoaderTest extends \PHPUnit_Framework_TestCase

        $xError = array(
            'type' => E_USER_DEPRECATED,
-            'message' => 'Test\Symfony\Component\Debug\Tests\Float uses a reserved class name (Float) that will break on PHP 7 and higher',
+            'message' => 'The "Test\Symfony\Component\Debug\Tests\Float" class uses the reserved name "Float", it will break on PHP 7 and higher',
        );

        $this->assertSame($xError, $lastError);
    }
+
+    public function testExtendedFinalClass()
+    {
+        set_error_handler(function () { return false; });
+        $e = error_reporting(0);
+        trigger_error('', E_USER_NOTICE);
+
+        class_exists('Test\\'.__NAMESPACE__.'\\ExtendsFinalClass', true);
+
+        error_reporting($e);
+        restore_error_handler();
+
+        $lastError = error_get_last();
+        unset($lastError['file'], $lastError['line']);
+
+        $xError = array(
+            'type' => E_USER_DEPRECATED,
+            'message' => 'The "Symfony\Component\Debug\Tests\Fixtures\FinalClass" class is considered final since version 3.3. It may change without further notice as of its next major version. You should not extend it from "Test\Symfony\Component\Debug\Tests\ExtendsFinalClass".',
+        );
+
+        $this->assertSame($xError, $lastError);
+    }
+
+    public function testExtendedFinalMethod()
+    {
+        set_error_handler(function () { return false; });
+        $e = error_reporting(0);
+        trigger_error('', E_USER_NOTICE);
+
+        class_exists(__NAMESPACE__.'\\Fixtures\\ExtendedFinalMethod', true);
+
+        error_reporting($e);
+        restore_error_handler();
+
+        $lastError = error_get_last();
+        unset($lastError['file'], $lastError['line']);
+
+        $xError = array(
+            'type' => E_USER_DEPRECATED,
+            'message' => 'The "Symfony\Component\Debug\Tests\Fixtures\FinalMethod::finalMethod()" method is considered final since version 3.3. It may change without further notice as of its next major version. You should not extend it from "Symfony\Component\Debug\Tests\Fixtures\ExtendedFinalMethod".',
+        );
+
+        $this->assertSame($xError, $lastError);
+    }
+
+    public function testExtendedDeprecatedMethodDoesntTriggerAnyNotice()
+    {
+        set_error_handler(function () { return false; });
+        $e = error_reporting(0);
+        trigger_error('', E_USER_NOTICE);
+
+        class_exists('Test\\'.__NAMESPACE__.'\\ExtendsAnnotatedClass', true);
+
+        error_reporting($e);
+        restore_error_handler();
+
+        $lastError = error_get_last();
+        unset($lastError['file'], $lastError['line']);
+
+        $this->assertSame(array('type' => E_USER_NOTICE, 'message' => ''), $lastError);
+    }
+
+    public function testInternalsUse()
+    {
+        $deprecations = array();
+        set_error_handler(function ($type, $msg) use (&$deprecations) { $deprecations[] = $msg; });
+        $e = error_reporting(E_USER_DEPRECATED);
+
+        class_exists('Test\\'.__NAMESPACE__.'\\ExtendsInternals', true);
+
+        error_reporting($e);
+        restore_error_handler();
+
+        $this->assertSame($deprecations, array(
+            'The "Symfony\Component\Debug\Tests\Fixtures\InternalClass" class is considered internal since version 3.4. It may change without further notice. You should not use it from "Test\Symfony\Component\Debug\Tests\ExtendsInternalsParent".',
+            'The "Symfony\Component\Debug\Tests\Fixtures\InternalInterface" interface is considered internal. It may change without further notice. You should not use it from "Test\Symfony\Component\Debug\Tests\ExtendsInternalsParent".',
+            'The "Symfony\Component\Debug\Tests\Fixtures\InternalTrait" trait is considered internal. It may change without further notice. You should not use it from "Test\Symfony\Component\Debug\Tests\ExtendsInternals".',
+            'The "Symfony\Component\Debug\Tests\Fixtures\InternalTrait2::internalMethod()" method is considered internal since version 3.4. It may change without further notice. You should not extend it from "Test\Symfony\Component\Debug\Tests\ExtendsInternals".',
+        ));
+    }
 }

 class ClassLoader
@@ -290,16 +390,12 @@ class ClassLoader
            eval('namespace '.__NAMESPACE__.'; class TestingStacking { function foo() {} }');
        } elseif (__NAMESPACE__.'\TestingCaseMismatch' === $class) {
            eval('namespace '.__NAMESPACE__.'; class TestingCaseMisMatch {}');
-        } elseif (__NAMESPACE__.'\Fixtures\CaseMismatch' === $class) {
-            return $fixtureDir.'CaseMismatch.php';
        } elseif (__NAMESPACE__.'\Fixtures\Psr4CaseMismatch' === $class) {
            return $fixtureDir.'psr4'.DIRECTORY_SEPARATOR.'Psr4CaseMismatch.php';
        } elseif (__NAMESPACE__.'\Fixtures\NotPSR0' === $class) {
            return $fixtureDir.'reallyNotPsr0.php';
        } elseif (__NAMESPACE__.'\Fixtures\NotPSR0bis' === $class) {
            return $fixtureDir.'notPsr0Bis.php';
-        } elseif (__NAMESPACE__.'\Fixtures\DeprecatedInterface' === $class) {
-            return $fixtureDir.'DeprecatedInterface.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) {
@@ -310,6 +406,20 @@ class ClassLoader
            eval('namespace Test\\'.__NAMESPACE__.'; class NonDeprecatedInterfaceClass implements \\'.__NAMESPACE__.'\Fixtures\NonDeprecatedInterface {}');
        } elseif ('Test\\'.__NAMESPACE__.'\Float' === $class) {
            eval('namespace Test\\'.__NAMESPACE__.'; class Float {}');
+        } elseif ('Test\\'.__NAMESPACE__.'\ExtendsFinalClass' === $class) {
+            eval('namespace Test\\'.__NAMESPACE__.'; class ExtendsFinalClass extends \\'.__NAMESPACE__.'\Fixtures\FinalClass {}');
+        } elseif ('Test\\'.__NAMESPACE__.'\ExtendsAnnotatedClass' === $class) {
+            eval('namespace Test\\'.__NAMESPACE__.'; class ExtendsAnnotatedClass extends \\'.__NAMESPACE__.'\Fixtures\AnnotatedClass {
+                public function deprecatedMethod() { }
+            }');
+        } elseif ('Test\\'.__NAMESPACE__.'\ExtendsInternals' === $class) {
+            eval('namespace Test\\'.__NAMESPACE__.'; class ExtendsInternals extends ExtendsInternalsParent {
+                use \\'.__NAMESPACE__.'\Fixtures\InternalTrait;
+
+                public function internalMethod() { }
+            }');
+        } elseif ('Test\\'.__NAMESPACE__.'\ExtendsInternalsParent' === $class) {
+            eval('namespace Test\\'.__NAMESPACE__.'; class ExtendsInternalsParent extends \\'.__NAMESPACE__.'\Fixtures\InternalClass implements \\'.__NAMESPACE__.'\Fixtures\InternalInterface { }');
        }
    }
 }
--- a/Tests/ErrorHandlerTest.php
+++ b/Tests/ErrorHandlerTest.php
@@ -11,10 +11,11 @@

 namespace Symfony\Component\Debug\Tests;

+use PHPUnit\Framework\TestCase;
 use Psr\Log\LogLevel;
-use Symfony\Component\Debug\ErrorHandler;
 use Symfony\Component\Debug\BufferingLogger;
-use Symfony\Component\Debug\Exception\ContextErrorException;
+use Symfony\Component\Debug\ErrorHandler;
+use Symfony\Component\Debug\Exception\SilencedErrorContext;

 /**
 * ErrorHandlerTest.
@@ -22,7 +23,7 @@ use Symfony\Component\Debug\Exception\ContextErrorException;
 * @author Robert Schönthal <seroscho@googlemail.com>
 * @author Nicolas Grekas <p@tchwork.com>
 */
-class ErrorHandlerTest extends \PHPUnit_Framework_TestCase
+class ErrorHandlerTest extends TestCase
 {
    public function testRegister()
    {
@@ -34,7 +35,7 @@ class ErrorHandlerTest extends \PHPUnit_Framework_TestCase

            $newHandler = new ErrorHandler();

-            $this->assertSame($newHandler, ErrorHandler::register($newHandler, false));
+            $this->assertSame($handler, ErrorHandler::register($newHandler, false));
            $h = set_error_handler('var_dump');
            restore_error_handler();
            $this->assertSame(array($handler, 'handleError'), $h);
@@ -64,35 +65,54 @@ class ErrorHandlerTest extends \PHPUnit_Framework_TestCase
        }
    }

+    public function testErrorGetLast()
+    {
+        $handler = ErrorHandler::register();
+        $logger = $this->getMockBuilder('Psr\Log\LoggerInterface')->getMock();
+        $handler->setDefaultLogger($logger);
+        $handler->screamAt(E_ALL);
+
+        try {
+            @trigger_error('Hello', E_USER_WARNING);
+            $expected = array(
+                'type' => E_USER_WARNING,
+                'message' => 'Hello',
+                'file' => __FILE__,
+                'line' => __LINE__ - 5,
+            );
+            $this->assertSame($expected, error_get_last());
+        } catch (\Exception $e) {
+            restore_error_handler();
+            restore_exception_handler();
+
+            throw $e;
+        }
+    }
+
    public function testNotice()
    {
        ErrorHandler::register();

        try {
            self::triggerNotice($this);
-            $this->fail('ContextErrorException expected');
-        } catch (ContextErrorException $exception) {
+            $this->fail('ErrorException expected');
+        } catch (\ErrorException $exception) {
            // if an exception is thrown, the test passed
            $this->assertEquals(E_NOTICE, $exception->getSeverity());
            $this->assertEquals(__FILE__, $exception->getFile());
            $this->assertRegExp('/^Notice: Undefined variable: (foo|bar)/', $exception->getMessage());
-            $this->assertArrayHasKey('foobar', $exception->getContext());

            $trace = $exception->getTrace();
+
            $this->assertEquals(__FILE__, $trace[0]['file']);
-            $this->assertEquals('Symfony\Component\Debug\ErrorHandler', $trace[0]['class']);
-            $this->assertEquals('handleError', $trace[0]['function']);
-            $this->assertEquals('->', $trace[0]['type']);
+            $this->assertEquals(__CLASS__, $trace[0]['class']);
+            $this->assertEquals('triggerNotice', $trace[0]['function']);
+            $this->assertEquals('::', $trace[0]['type']);

-            $this->assertEquals(__FILE__, $trace[1]['file']);
+            $this->assertEquals(__FILE__, $trace[0]['file']);
            $this->assertEquals(__CLASS__, $trace[1]['class']);
-            $this->assertEquals('triggerNotice', $trace[1]['function']);
-            $this->assertEquals('::', $trace[1]['type']);
-
-            $this->assertEquals(__FILE__, $trace[1]['file']);
-            $this->assertEquals(__CLASS__, $trace[2]['class']);
-            $this->assertEquals(__FUNCTION__, $trace[2]['function']);
-            $this->assertEquals('->', $trace[2]['type']);
+            $this->assertEquals(__FUNCTION__, $trace[1]['function']);
+            $this->assertEquals('->', $trace[1]['type']);
        } finally {
            restore_error_handler();
            restore_exception_handler();
@@ -102,8 +122,6 @@ class ErrorHandlerTest extends \PHPUnit_Framework_TestCase
    // dummy function to test trace in error handler.
    private static function triggerNotice($that)
    {
-        // dummy variable to check for in error handler.
-        $foobar = 123;
        $that->assertSame('', $foo.$foo.$bar);
    }

@@ -202,11 +220,12 @@ class ErrorHandlerTest extends \PHPUnit_Framework_TestCase

            $warnArgCheck = function ($logLevel, $message, $context) {
                $this->assertEquals('info', $logLevel);
-                $this->assertEquals('foo', $message);
-                $this->assertArrayHasKey('type', $context);
-                $this->assertEquals($context['type'], E_USER_DEPRECATED);
-                $this->assertArrayHasKey('stack', $context);
-                $this->assertInternalType('array', $context['stack']);
+                $this->assertEquals('User Deprecated: foo', $message);
+                $this->assertArrayHasKey('exception', $context);
+                $exception = $context['exception'];
+                $this->assertInstanceOf(\ErrorException::class, $exception);
+                $this->assertSame('User Deprecated: foo', $exception->getMessage());
+                $this->assertSame(E_USER_DEPRECATED, $exception->getSeverity());
            };

            $logger
@@ -224,10 +243,17 @@ class ErrorHandlerTest extends \PHPUnit_Framework_TestCase

            $logger = $this->getMockBuilder('Psr\Log\LoggerInterface')->getMock();

-            $logArgCheck = function ($level, $message, $context) {
-                $this->assertEquals('Undefined variable: undefVar', $message);
-                $this->assertArrayHasKey('type', $context);
-                $this->assertEquals($context['type'], E_NOTICE);
+            $line = null;
+            $logArgCheck = function ($level, $message, $context) use (&$line) {
+                $this->assertEquals('Notice: Undefined variable: undefVar', $message);
+                $this->assertArrayHasKey('exception', $context);
+                $exception = $context['exception'];
+                $this->assertInstanceOf(SilencedErrorContext::class, $exception);
+                $this->assertSame(E_NOTICE, $exception->getSeverity());
+                $this->assertSame(__FILE__, $exception->getFile());
+                $this->assertSame($line, $exception->getLine());
+                $this->assertNotEmpty($exception->getTrace());
+                $this->assertSame(1, $exception->count);
            };

            $logger
@@ -240,6 +266,7 @@ class ErrorHandlerTest extends \PHPUnit_Framework_TestCase
            $handler->setDefaultLogger($logger, E_NOTICE);
            $handler->screamAt(E_NOTICE);
            unset($undefVar);
+            $line = __LINE__ + 1;
            @$undefVar++;

            restore_error_handler();
@@ -278,9 +305,10 @@ class ErrorHandlerTest extends \PHPUnit_Framework_TestCase
    {
        $logArgCheck = function ($level, $message, $context) {
            $this->assertEquals(LogLevel::INFO, $level);
-            $this->assertArrayHasKey('level', $context);
-            $this->assertEquals(E_RECOVERABLE_ERROR | E_USER_ERROR | E_DEPRECATED | E_USER_DEPRECATED, $context['level']);
-            $this->assertArrayHasKey('stack', $context);
+            $this->assertArrayHasKey('exception', $context);
+            $exception = $context['exception'];
+            $this->assertInstanceOf(\ErrorException::class, $exception);
+            $this->assertSame('User Deprecated: Foo deprecation', $exception->getMessage());
        };

        $logger = $this->getMockBuilder('Psr\Log\LoggerInterface')->getMock();
@@ -295,6 +323,9 @@ class ErrorHandlerTest extends \PHPUnit_Framework_TestCase
        @$handler->handleError(E_USER_DEPRECATED, 'Foo deprecation', __FILE__, __LINE__, array());
    }

+    /**
+     * @group no-hhvm
+     */
    public function testHandleException()
    {
        try {
@@ -305,9 +336,9 @@ class ErrorHandlerTest extends \PHPUnit_Framework_TestCase
            $logger = $this->getMockBuilder('Psr\Log\LoggerInterface')->getMock();

            $logArgCheck = function ($level, $message, $context) {
-                $this->assertEquals('Uncaught Exception: foo', $message);
-                $this->assertArrayHasKey('type', $context);
-                $this->assertEquals($context['type'], E_ERROR);
+                $this->assertSame('Uncaught Exception: foo', $message);
+                $this->assertArrayHasKey('exception', $context);
+                $this->assertInstanceOf(\Exception::class, $context['exception']);
            };

            $logger
@@ -336,6 +367,9 @@ class ErrorHandlerTest extends \PHPUnit_Framework_TestCase
        }
    }

+    /**
+     * @group legacy
+     */
    public function testErrorStacking()
    {
        try {
@@ -349,7 +383,7 @@ class ErrorHandlerTest extends \PHPUnit_Framework_TestCase
                ->method('log')
                ->withConsecutive(
                    array($this->equalTo(LogLevel::WARNING), $this->equalTo('Dummy log')),
-                    array($this->equalTo(LogLevel::DEBUG), $this->equalTo('Silenced warning'))
+                    array($this->equalTo(LogLevel::DEBUG), $this->equalTo('User Warning: Silenced warning'))
                )
            ;

@@ -391,23 +425,56 @@ class ErrorHandlerTest extends \PHPUnit_Framework_TestCase
        $this->assertSame($loggers, $handler->setLoggers(array()));

        $handler->handleError(E_DEPRECATED, 'Foo message', __FILE__, 123, array());
-        $expectedLog = array(LogLevel::INFO, 'Foo message', array('type' => E_DEPRECATED, 'file' => __FILE__, 'line' => 123, 'level' => error_reporting()));

        $logs = $bootLogger->cleanLogs();
-        unset($logs[0][2]['stack']);

-        $this->assertSame(array($expectedLog), $logs);
+        $this->assertCount(1, $logs);
+        $log = $logs[0];
+        $this->assertSame('info', $log[0]);
+        $this->assertSame('Deprecated: Foo message', $log[1]);
+        $this->assertArrayHasKey('exception', $log[2]);
+        $exception = $log[2]['exception'];
+        $this->assertInstanceOf(\ErrorException::class, $exception);
+        $this->assertSame('Deprecated: Foo message', $exception->getMessage());
+        $this->assertSame(__FILE__, $exception->getFile());
+        $this->assertSame(123, $exception->getLine());
+        $this->assertSame(E_DEPRECATED, $exception->getSeverity());

-        $bootLogger->log($expectedLog[0], $expectedLog[1], $expectedLog[2]);
+        $bootLogger->log(LogLevel::WARNING, 'Foo message', array('exception' => $exception));

        $mockLogger = $this->getMockBuilder('Psr\Log\LoggerInterface')->getMock();
        $mockLogger->expects($this->once())
            ->method('log')
-            ->with(LogLevel::WARNING, 'Foo message', $expectedLog[2]);
+            ->with(LogLevel::WARNING, 'Foo message', array('exception' => $exception));

        $handler->setLoggers(array(E_DEPRECATED => array($mockLogger, LogLevel::WARNING)));
    }

+    /**
+     * @group no-hhvm
+     */
+    public function testSettingLoggerWhenExceptionIsBuffered()
+    {
+        $bootLogger = new BufferingLogger();
+        $handler = new ErrorHandler($bootLogger);
+
+        $exception = new \Exception('Foo message');
+
+        $mockLogger = $this->getMockBuilder('Psr\Log\LoggerInterface')->getMock();
+        $mockLogger->expects($this->once())
+            ->method('log')
+            ->with(LogLevel::CRITICAL, 'Uncaught Exception: Foo message', array('exception' => $exception));
+
+        $handler->setExceptionHandler(function () use ($handler, $mockLogger) {
+            $handler->setDefaultLogger($mockLogger);
+        });
+
+        $handler->handleException($exception);
+    }
+
+    /**
+     * @group no-hhvm
+     */
    public function testHandleFatalError()
    {
        try {
@@ -424,8 +491,8 @@ class ErrorHandlerTest extends \PHPUnit_Framework_TestCase

            $logArgCheck = function ($level, $message, $context) {
                $this->assertEquals('Fatal Parse Error: foo', $message);
-                $this->assertArrayHasKey('type', $context);
-                $this->assertEquals($context['type'], E_PARSE);
+                $this->assertArrayHasKey('exception', $context);
+                $this->assertInstanceOf(\Exception::class, $context['exception']);
            };

            $logger
@@ -466,6 +533,9 @@ class ErrorHandlerTest extends \PHPUnit_Framework_TestCase
        $this->assertStringStartsWith("Attempted to load class \"Foo\" from the global namespace.\nDid you forget a \"use\" statement", $args[0]->getMessage());
    }

+    /**
+     * @group no-hhvm
+     */
    public function testHandleFatalErrorOnHHVM()
    {
        try {
@@ -477,14 +547,7 @@ class ErrorHandlerTest extends \PHPUnit_Framework_TestCase
                ->method('log')
                ->with(
                    $this->equalTo(LogLevel::CRITICAL),
-                    $this->equalTo('Fatal Error: foo'),
-                    $this->equalTo(array(
-                        'type' => 1,
-                        'file' => 'bar',
-                        'line' => 123,
-                        'level' => -1,
-                        'stack' => array(456),
-                    ))
+                    $this->equalTo('Fatal Error: foo')
                )
            ;

@@ -506,4 +569,18 @@ class ErrorHandlerTest extends \PHPUnit_Framework_TestCase
            restore_exception_handler();
        }
    }
+
+    /**
+     * @expectedException \Exception
+     * @group no-hhvm
+     */
+    public function testCustomExceptionHandler()
+    {
+        $handler = new ErrorHandler();
+        $handler->setExceptionHandler(function ($e) use ($handler) {
+            $handler->handleException($e);
+        });
+
+        $handler->handleException(new \Exception());
+    }
 }
--- a/Tests/Exception/FlattenExceptionTest.php
+++ b/Tests/Exception/FlattenExceptionTest.php
@@ -11,7 +11,9 @@

 namespace Symfony\Component\Debug\Tests\Exception;

+use PHPUnit\Framework\TestCase;
 use Symfony\Component\Debug\Exception\FlattenException;
+use Symfony\Component\HttpFoundation\Exception\SuspiciousOperationException;
 use Symfony\Component\HttpKernel\Exception\NotFoundHttpException;
 use Symfony\Component\HttpKernel\Exception\MethodNotAllowedHttpException;
 use Symfony\Component\HttpKernel\Exception\UnauthorizedHttpException;
@@ -27,7 +29,7 @@ use Symfony\Component\HttpKernel\Exception\ServiceUnavailableHttpException;
 use Symfony\Component\HttpKernel\Exception\TooManyRequestsHttpException;
 use Symfony\Component\HttpKernel\Exception\UnsupportedMediaTypeHttpException;

-class FlattenExceptionTest extends \PHPUnit_Framework_TestCase
+class FlattenExceptionTest extends TestCase
 {
    public function testStatusCode()
    {
@@ -78,6 +80,11 @@ class FlattenExceptionTest extends \PHPUnit_Framework_TestCase

        $flattened = FlattenException::create(new UnsupportedMediaTypeHttpException());
        $this->assertEquals('415', $flattened->getStatusCode());
+
+        if (class_exists(SuspiciousOperationException::class)) {
+            $flattened = FlattenException::create(new SuspiciousOperationException());
+            $this->assertEquals('400', $flattened->getStatusCode());
+        }
    }

    public function testHeadersForHttpException()
@@ -104,7 +111,7 @@ class FlattenExceptionTest extends \PHPUnit_Framework_TestCase
    /**
     * @dataProvider flattenDataProvider
     */
-    public function testFlattenHttpException(\Exception $exception, $statusCode)
+    public function testFlattenHttpException(\Exception $exception)
    {
        $flattened = FlattenException::create($exception);
        $flattened2 = FlattenException::create($exception);
@@ -119,7 +126,7 @@ class FlattenExceptionTest extends \PHPUnit_Framework_TestCase
    /**
     * @dataProvider flattenDataProvider
     */
-    public function testPrevious(\Exception $exception, $statusCode)
+    public function testPrevious(\Exception $exception)
    {
        $flattened = FlattenException::create($exception);
        $flattened2 = FlattenException::create($exception);
@@ -166,7 +173,7 @@ class FlattenExceptionTest extends \PHPUnit_Framework_TestCase
    /**
     * @dataProvider flattenDataProvider
     */
-    public function testToArray(\Exception $exception, $statusCode)
+    public function testToArray(\Exception $exception)
    {
        $flattened = FlattenException::create($exception);
        $flattened->setTrace(array(), 'foo.php', 123);
@@ -186,12 +193,75 @@ class FlattenExceptionTest extends \PHPUnit_Framework_TestCase
    public function flattenDataProvider()
    {
        return array(
-            array(new \Exception('test', 123), 500),
+            array(new \Exception('test', 123)),
        );
    }

+    public function testArguments()
+    {
+        $dh = opendir(__DIR__);
+        $fh = tmpfile();
+
+        $incomplete = unserialize('O:14:"BogusTestClass":0:{}');
+
+        $exception = $this->createException(array(
+            (object) array('foo' => 1),
+            new NotFoundHttpException(),
+            $incomplete,
+            $dh,
+            $fh,
+            function () {},
+            array(1, 2),
+            array('foo' => 123),
+            null,
+            true,
+            false,
+            0,
+            0.0,
+            '0',
+            '',
+            INF,
+            NAN,
+        ));
+
+        $flattened = FlattenException::create($exception);
+        $trace = $flattened->getTrace();
+        $args = $trace[1]['args'];
+        $array = $args[0][1];
+
+        closedir($dh);
+        fclose($fh);
+
+        $i = 0;
+        $this->assertSame(array('object', 'stdClass'), $array[$i++]);
+        $this->assertSame(array('object', 'Symfony\Component\HttpKernel\Exception\NotFoundHttpException'), $array[$i++]);
+        $this->assertSame(array('incomplete-object', 'BogusTestClass'), $array[$i++]);
+        $this->assertSame(array('resource', defined('HHVM_VERSION') ? 'Directory' : 'stream'), $array[$i++]);
+        $this->assertSame(array('resource', 'stream'), $array[$i++]);
+
+        $args = $array[$i++];
+        $this->assertSame($args[0], 'object');
+        $this->assertTrue('Closure' === $args[1] || is_subclass_of($args[1], '\Closure'), 'Expect object class name to be Closure or a subclass of Closure.');
+
+        $this->assertSame(array('array', array(array('integer', 1), array('integer', 2))), $array[$i++]);
+        $this->assertSame(array('array', array('foo' => array('integer', 123))), $array[$i++]);
+        $this->assertSame(array('null', null), $array[$i++]);
+        $this->assertSame(array('boolean', true), $array[$i++]);
+        $this->assertSame(array('boolean', false), $array[$i++]);
+        $this->assertSame(array('integer', 0), $array[$i++]);
+        $this->assertSame(array('float', 0.0), $array[$i++]);
+        $this->assertSame(array('string', '0'), $array[$i++]);
+        $this->assertSame(array('string', ''), $array[$i++]);
+        $this->assertSame(array('float', INF), $array[$i++]);
+
+        // assertEquals() does not like NAN values.
+        $this->assertEquals($array[$i][0], 'float');
+        $this->assertTrue(is_nan($array[$i++][1]));
+    }
+
    public function testRecursionInArguments()
    {
+        $a = null;
        $a = array('foo', array(2, &$a));
        $exception = $this->createException($a);

@@ -216,6 +286,9 @@ class FlattenExceptionTest extends \PHPUnit_Framework_TestCase

        $flattened = FlattenException::create($exception);
        $trace = $flattened->getTrace();
+
+        $this->assertSame($trace[1]['args'][0], array('array', array('array', '*SKIPPED over 10000 entries*')));
+
        $serializeTrace = serialize($trace);

        $this->assertContains('*SKIPPED over 10000 entries*', $serializeTrace);
@@ -226,45 +299,4 @@ class FlattenExceptionTest extends \PHPUnit_Framework_TestCase
    {
        return new \Exception();
    }
-
-    public function testSetTraceIncompleteClass()
-    {
-        $flattened = FlattenException::create(new \Exception('test', 123));
-        $flattened->setTrace(
-            array(
-                array(
-                    'file' => __FILE__,
-                    'line' => 123,
-                    'function' => 'test',
-                    'args' => array(
-                        unserialize('O:14:"BogusTestClass":0:{}'),
-                    ),
-                ),
-            ),
-            'foo.php', 123
-        );
-
-        $this->assertEquals(array(
-            array(
-                'message' => 'test',
-                'class' => 'Exception',
-                'trace' => array(
-                    array(
-                        'namespace' => '', 'short_class' => '', 'class' => '', 'type' => '', 'function' => '',
-                        'file' => 'foo.php', 'line' => 123,
-                        'args' => array(),
-                    ),
-                    array(
-                        'namespace' => '', 'short_class' => '', 'class' => '', 'type' => '', 'function' => 'test',
-                        'file' => __FILE__, 'line' => 123,
-                        'args' => array(
-                            array(
-                                'incomplete-object', 'BogusTestClass',
-                            ),
-                        ),
-                    ),
-                ),
-            ),
-        ), $flattened->toArray());
-    }
 }
--- a/Tests/ExceptionHandlerTest.php
+++ b/Tests/ExceptionHandlerTest.php
@@ -11,6 +11,7 @@

 namespace Symfony\Component\Debug\Tests;

+use PHPUnit\Framework\TestCase;
 use Symfony\Component\Debug\ExceptionHandler;
 use Symfony\Component\Debug\Exception\OutOfMemoryException;
 use Symfony\Component\HttpKernel\Exception\NotFoundHttpException;
@@ -18,7 +19,7 @@ use Symfony\Component\HttpKernel\Exception\MethodNotAllowedHttpException;

 require_once __DIR__.'/HeaderMock.php';

-class ExceptionHandlerTest extends \PHPUnit_Framework_TestCase
+class ExceptionHandlerTest extends TestCase
 {
    protected function setUp()
    {
@@ -38,8 +39,8 @@ class ExceptionHandlerTest extends \PHPUnit_Framework_TestCase
        $handler->sendPhpResponse(new \RuntimeException('Foo'));
        $response = ob_get_clean();

-        $this->assertContains('<h1>Whoops, looks like something went wrong.</h1>', $response);
-        $this->assertNotContains('<h2 class="block_exception clear_fix">', $response);
+        $this->assertContains('Whoops, looks like something went wrong.', $response);
+        $this->assertNotContains('<div class="trace trace-as-html">', $response);

        $handler = new ExceptionHandler(true);

@@ -47,8 +48,8 @@ class ExceptionHandlerTest extends \PHPUnit_Framework_TestCase
        $handler->sendPhpResponse(new \RuntimeException('Foo'));
        $response = ob_get_clean();

-        $this->assertContains('<h1>Whoops, looks like something went wrong.</h1>', $response);
-        $this->assertContains('<h2 class="block_exception clear_fix">', $response);
+        $this->assertContains('Whoops, looks like something went wrong.', $response);
+        $this->assertContains('<div class="trace trace-as-html">', $response);
    }

    public function testStatusCode()
@@ -93,7 +94,7 @@ class ExceptionHandlerTest extends \PHPUnit_Framework_TestCase
        $handler->sendPhpResponse(new \RuntimeException('Foo', 0, new \RuntimeException('Bar')));
        $response = ob_get_clean();

-        $this->assertStringMatchesFormat('%A<span class="exception_message">Foo</span>%A<span class="exception_message">Bar</span>%A', $response);
+        $this->assertStringMatchesFormat('%A<p class="break-long-words trace-message">Foo</p>%A<p class="break-long-words trace-message">Bar</p>%A', $response);
    }

    public function testHandle()
--- a/Tests/FatalErrorHandler/ClassNotFoundFatalErrorHandlerTest.php
+++ b/Tests/FatalErrorHandler/ClassNotFoundFatalErrorHandlerTest.php
@@ -11,13 +11,13 @@

 namespace Symfony\Component\Debug\Tests\FatalErrorHandler;

+use PHPUnit\Framework\TestCase;
 use Symfony\Component\Debug\Exception\FatalErrorException;
-use Symfony\Component\ClassLoader\ClassLoader as SymfonyClassLoader;
 use Symfony\Component\Debug\FatalErrorHandler\ClassNotFoundFatalErrorHandler;
 use Symfony\Component\Debug\DebugClassLoader;
 use Composer\Autoload\ClassLoader as ComposerClassLoader;

-class ClassNotFoundFatalErrorHandlerTest extends \PHPUnit_Framework_TestCase
+class ClassNotFoundFatalErrorHandlerTest extends TestCase
 {
    public static function setUpBeforeClass()
    {
@@ -69,12 +69,10 @@ class ClassNotFoundFatalErrorHandlerTest extends \PHPUnit_Framework_TestCase

    public function provideClassNotFoundData()
    {
-        $prefixes = array('Symfony\Component\Debug\Exception\\' => realpath(__DIR__.'/../../Exception'));
+        $autoloader = new ComposerClassLoader();
+        $autoloader->add('Symfony\Component\Debug\Exception\\', realpath(__DIR__.'/../../Exception'));

-        $symfonyAutoloader = new SymfonyClassLoader();
-        $symfonyAutoloader->addPrefixes($prefixes);
-
-        $debugClassLoader = new DebugClassLoader(array($symfonyAutoloader, 'loadClass'));
+        $debugClassLoader = new DebugClassLoader(array($autoloader, 'loadClass'));

        return array(
            array(
@@ -130,7 +128,7 @@ class ClassNotFoundFatalErrorHandlerTest extends \PHPUnit_Framework_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\"?",
-                array($symfonyAutoloader, 'loadClass'),
+                array($autoloader, 'loadClass'),
            ),
            array(
                array(
--- a/Tests/FatalErrorHandler/UndefinedFunctionFatalErrorHandlerTest.php
+++ b/Tests/FatalErrorHandler/UndefinedFunctionFatalErrorHandlerTest.php
@@ -11,10 +11,11 @@

 namespace Symfony\Component\Debug\Tests\FatalErrorHandler;

+use PHPUnit\Framework\TestCase;
 use Symfony\Component\Debug\Exception\FatalErrorException;
 use Symfony\Component\Debug\FatalErrorHandler\UndefinedFunctionFatalErrorHandler;

-class UndefinedFunctionFatalErrorHandlerTest extends \PHPUnit_Framework_TestCase
+class UndefinedFunctionFatalErrorHandlerTest extends TestCase
 {
    /**
     * @dataProvider provideUndefinedFunctionData
--- a/Tests/FatalErrorHandler/UndefinedMethodFatalErrorHandlerTest.php
+++ b/Tests/FatalErrorHandler/UndefinedMethodFatalErrorHandlerTest.php
@@ -11,10 +11,11 @@

 namespace Symfony\Component\Debug\Tests\FatalErrorHandler;

+use PHPUnit\Framework\TestCase;
 use Symfony\Component\Debug\Exception\FatalErrorException;
 use Symfony\Component\Debug\FatalErrorHandler\UndefinedMethodFatalErrorHandler;

-class UndefinedMethodFatalErrorHandlerTest extends \PHPUnit_Framework_TestCase
+class UndefinedMethodFatalErrorHandlerTest extends TestCase
 {
    /**
     * @dataProvider provideUndefinedMethodData
--- a/Tests/Fixtures/AnnotatedClass.php
+++ b/Tests/Fixtures/AnnotatedClass.php
@@ -0,0 +1,13 @@
+<?php
+
+namespace Symfony\Component\Debug\Tests\Fixtures;
+
+class AnnotatedClass
+{
+    /**
+     * @deprecated since version 3.4.
+     */
+    public function deprecatedMethod()
+    {
+    }
+}
--- a/Tests/Fixtures/DeprecatedClass.php
+++ b/Tests/Fixtures/DeprecatedClass.php
@@ -4,7 +4,7 @@ namespace Symfony\Component\Debug\Tests\Fixtures;

 /**
 * @deprecated but this is a test
- *             deprecation notice.
+ *             deprecation notice
 * @foobar
 */
 class DeprecatedClass
--- a/Tests/Fixtures/DeprecatedInterface.php
+++ b/Tests/Fixtures/DeprecatedInterface.php
@@ -4,7 +4,7 @@ namespace Symfony\Component\Debug\Tests\Fixtures;

 /**
 * @deprecated but this is a test
- *             deprecation notice.
+ *             deprecation notice
 * @foobar
 */
 interface DeprecatedInterface
--- a/Tests/Fixtures/ExtendedFinalMethod.php
+++ b/Tests/Fixtures/ExtendedFinalMethod.php
@@ -0,0 +1,17 @@
+<?php
+
+namespace Symfony\Component\Debug\Tests\Fixtures;
+
+class ExtendedFinalMethod extends FinalMethod
+{
+    /**
+     * {@inheritdoc}
+     */
+    public function finalMethod()
+    {
+    }
+
+    public function anotherMethod()
+    {
+    }
+}
--- a/Tests/Fixtures/FinalClass.php
+++ b/Tests/Fixtures/FinalClass.php
@@ -0,0 +1,10 @@
+<?php
+
+namespace Symfony\Component\Debug\Tests\Fixtures;
+
+/**
+ * @final since version 3.3.
+ */
+class FinalClass
+{
+}
--- a/Tests/Fixtures/FinalMethod.php
+++ b/Tests/Fixtures/FinalMethod.php
@@ -0,0 +1,17 @@
+<?php
+
+namespace Symfony\Component\Debug\Tests\Fixtures;
+
+class FinalMethod
+{
+    /**
+     * @final since version 3.3.
+     */
+    public function finalMethod()
+    {
+    }
+
+    public function anotherMethod()
+    {
+    }
+}
--- a/Tests/Fixtures/InternalClass.php
+++ b/Tests/Fixtures/InternalClass.php
@@ -0,0 +1,15 @@
+<?php
+
+namespace Symfony\Component\Debug\Tests\Fixtures;
+
+/**
+ * @internal since version 3.4.
+ */
+class InternalClass
+{
+    use InternalTrait2;
+
+    public function usedInInternalClass()
+    {
+    }
+}
--- a/Tests/Fixtures/InternalInterface.php
+++ b/Tests/Fixtures/InternalInterface.php
@@ -0,0 +1,10 @@
+<?php
+
+namespace Symfony\Component\Debug\Tests\Fixtures;
+
+/**
+ * @internal
+ */
+interface InternalInterface
+{
+}
--- a/Tests/Fixtures/InternalTrait.php
+++ b/Tests/Fixtures/InternalTrait.php
@@ -0,0 +1,10 @@
+<?php
+
+namespace Symfony\Component\Debug\Tests\Fixtures;
+
+/**
+ * @internal
+ */
+trait InternalTrait
+{
+}
--- a/Tests/Fixtures/InternalTrait2.php
+++ b/Tests/Fixtures/InternalTrait2.php
@@ -0,0 +1,23 @@
+<?php
+
+namespace Symfony\Component\Debug\Tests\Fixtures;
+
+/**
+ * @internal
+ */
+trait InternalTrait2
+{
+    /**
+     * @internal since version 3.4
+     */
+    public function internalMethod()
+    {
+    }
+
+    /**
+     * @internal but should not trigger a deprecation
+     */
+    public function usedInInternalClass()
+    {
+    }
+}
--- a/Tests/Fixtures/Throwing.php
+++ b/Tests/Fixtures/Throwing.php
@@ -0,0 +1,3 @@
+<?php
+
+throw new \Exception('boo');
--- a/Tests/phpt/debug_class_loader.phpt
+++ b/Tests/phpt/debug_class_loader.phpt
@@ -0,0 +1,26 @@
+--TEST--
+Test DebugClassLoader with previously loaded parents
+--FILE--
+<?php
+
+namespace Symfony\Component\Debug\Tests\Fixtures;
+
+use Symfony\Component\Debug\DebugClassLoader;
+
+$vendor = __DIR__;
+while (!file_exists($vendor.'/vendor')) {
+    $vendor = dirname($vendor);
+}
+require $vendor.'/vendor/autoload.php';
+
+class_exists(FinalMethod::class);
+
+set_error_handler(function ($type, $msg) { echo $msg, "\n"; });
+
+DebugClassLoader::enable();
+
+class_exists(ExtendedFinalMethod::class);
+
+?>
+--EXPECTF--
+The "Symfony\Component\Debug\Tests\Fixtures\FinalMethod::finalMethod()" method is considered final since version 3.3. It may change without further notice as of its next major version. You should not extend it from "Symfony\Component\Debug\Tests\Fixtures\ExtendedFinalMethod".
--- a/Tests/phpt/decorate_exception_hander.phpt
+++ b/Tests/phpt/decorate_exception_hander.phpt
@@ -0,0 +1,47 @@
+--TEST--
+Test catching fatal errors when handlers are nested
+--FILE--
+<?php
+
+namespace Symfony\Component\Debug;
+
+$vendor = __DIR__;
+while (!file_exists($vendor.'/vendor')) {
+    $vendor = dirname($vendor);
+}
+require $vendor.'/vendor/autoload.php';
+
+set_error_handler('var_dump');
+set_exception_handler('var_dump');
+
+ErrorHandler::register(null, false);
+
+if (true) {
+    class foo extends missing
+    {
+    }
+}
+
+?>
+--EXPECTF--
+Fatal error: Class 'Symfony\Component\Debug\missing' not found in %s on line %d
+object(Symfony\Component\Debug\Exception\ClassNotFoundException)#%d (8) {
+  ["message":protected]=>
+  string(131) "Attempted to load class "missing" from namespace "Symfony\Component\Debug".
+Did you forget a "use" statement for another namespace?"
+  ["string":"Exception":private]=>
+  string(0) ""
+  ["code":protected]=>
+  int(0)
+  ["file":protected]=>
+  string(%d) "%s"
+  ["line":protected]=>
+  int(%d)
+  ["trace":"Exception":private]=>
+  array(0) {
+  }
+  ["previous":"Exception":private]=>
+  NULL
+  ["severity":protected]=>
+  int(1)
+}
--- a/Tests/phpt/exception_rethrown.phpt
+++ b/Tests/phpt/exception_rethrown.phpt
@@ -0,0 +1,35 @@
+--TEST--
+Test rethrowing in custom exception handler
+--FILE--
+<?php
+
+namespace Symfony\Component\Debug;
+
+$vendor = __DIR__;
+while (!file_exists($vendor.'/vendor')) {
+    $vendor = dirname($vendor);
+}
+require $vendor.'/vendor/autoload.php';
+
+if (true) {
+    class TestLogger extends \Psr\Log\AbstractLogger
+    {
+        public function log($level, $message, array $context = array())
+        {
+            echo $message, "\n";
+        }
+    }
+}
+
+set_exception_handler(function ($e) { echo 123; throw $e; });
+ErrorHandler::register()->setDefaultLogger(new TestLogger());
+ini_set('display_errors', 1);
+
+throw new \Exception('foo');
+?>
+--EXPECTF--
+Uncaught Exception: foo
+123
+Fatal error: Uncaught %s:25
+Stack trace:
+%a
--- a/Tests/phpt/fatal_with_nested_handlers.phpt
+++ b/Tests/phpt/fatal_with_nested_handlers.phpt
@@ -0,0 +1,42 @@
+--TEST--
+Test catching fatal errors when handlers are nested
+--FILE--
+<?php
+
+namespace Symfony\Component\Debug;
+
+$vendor = __DIR__;
+while (!file_exists($vendor.'/vendor')) {
+    $vendor = dirname($vendor);
+}
+require $vendor.'/vendor/autoload.php';
+
+Debug::enable();
+ini_set('display_errors', 0);
+
+$eHandler = set_error_handler('var_dump');
+$xHandler = set_exception_handler('var_dump');
+
+var_dump(array(
+    $eHandler[0] === $xHandler[0] ? 'Error and exception handlers do match' : 'Error and exception handlers are different',
+));
+
+$eHandler[0]->setExceptionHandler('print_r');
+
+if (true) {
+    class Broken implements \Serializable
+    {
+    }
+}
+
+?>
+--EXPECTF--
+array(1) {
+  [0]=>
+  string(37) "Error and exception handlers do match"
+}
+object(Symfony\Component\Debug\Exception\FatalErrorException)#%d (%d) {
+  ["message":protected]=>
+  string(199) "Error: Class Symfony\Component\Debug\Broken contains 2 abstract methods and must therefore be declared abstract or implement the remaining methods (Serializable::serialize, Serializable::unserialize)"
+%a
+}
--- a/composer.json
+++ b/composer.json
@@ -16,15 +16,14 @@
        }
    ],
    "require": {
-        "php": ">=5.5.9",
+        "php": "^5.5.9|>=7.0.8",
        "psr/log": "~1.0"
    },
    "conflict": {
        "symfony/http-kernel": ">=2.3,<2.3.24|~2.4.0|>=2.5,<2.5.9|>=2.6,<2.6.2"
    },
    "require-dev": {
-        "symfony/class-loader": "~2.8|~3.0",
-        "symfony/http-kernel": "~2.8|~3.0"
+        "symfony/http-kernel": "~2.8|~3.0|~4.0"
    },
    "autoload": {
        "psr-4": { "Symfony\\Component\\Debug\\": "" },
@@ -35,7 +34,7 @@
    "minimum-stability": "dev",
    "extra": {
        "branch-alias": {
-            "dev-master": "3.1-dev"
+            "dev-master": "3.4-dev"
        }
    }
 }
--- a/phpunit.xml.dist
+++ b/phpunit.xml.dist
@@ -5,6 +5,8 @@
         backupGlobals="false"
         colors="true"
         bootstrap="vendor/autoload.php"
+         failOnRisky="true"
+         failOnWarning="true"
 >
    <php>
        <ini name="error_reporting" value="-1" />