[Debug] fix ClassNotFoundFatalErrorHandler

This PR was squashed before being merged into the 3.4 branch (closes #32800).

Discussion
----------

Improve some URLs

| Q             | A
| ------------- | ---
| Branch?       | 3.4 <!-- see below -->
| Bug fix?      | no
| New feature?  | no <!-- please update src/**/CHANGELOG.md files -->
| BC breaks?    | no     <!-- see https://symfony.com/bc -->
| Deprecations? | no <!-- please update UPGRADE-*.md and src/**/CHANGELOG.md files -->
| Tests pass?   | yes    <!-- please add some, will be required by reviewers -->
| Fixed tickets | N/A   <!-- #-prefixed issue number(s), if any -->
| License       | MIT
| Doc PR        | N/A <!-- required for new features -->

<!--
Replace this notice by a short README for your feature/bugfix. This will help people
understand your PR and can be used as a start for the documentation.

Additionally (see https://symfony.com/roadmap):
 - Bug fixes must be submitted against the lowest maintained branch where they apply
   (lowest branches are regularly merged to upper ones so they get the fixes too).
 - Features and deprecations must be submitted against branch 4.4.
 - Legacy code removals go to the master branch.
-->

Commits
-------

fab17a4487 Improve some URLs

BufferingLogger.php

@@ -0,0 +1,37 @@
+<?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;
+
+use Psr\Log\AbstractLogger;
+
+/**
+ * A buffering logger that stacks logs for later.
+ *
+ * @author Nicolas Grekas <p@tchwork.com>
+ */
+class BufferingLogger extends AbstractLogger
+{
+    private $logs = [];
+
+    public function log($level, $message, array $context = [])
+    {
+        $this->logs[] = [$level, $message, $context];
+    }
+
+    public function cleanLogs()
+    {
+        $logs = $this->logs;
+        $this->logs = [];
+
+        return $logs;
+    }
+}

CHANGELOG.md

@@ -1,6 +1,63 @@
 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
+-----
+
+* removed classes, methods and interfaces deprecated in 2.x
+
+2.8.0
+-----
+
+* added BufferingLogger for errors that happen before a proper logger is configured
+* allow throwing from `__toString()` with `return trigger_error($e, E_USER_ERROR);`
+* deprecate ExceptionHandler::createResponse
+
+2.7.0
+-----
+
+* added deprecations checking for parent interfaces/classes to DebugClassLoader
+* added ZTS support to symfony_debug extension
+* added symfony_debug_backtrace() to symfony_debug extension
+  to track the backtrace of fatal errors
+
+2.6.0
+-----
+
+* generalized ErrorHandler and ExceptionHandler,
+  with some new methods and others deprecated
+* enhanced error messages for uncaught exceptions
+
+2.5.0
+-----
+
+* added ExceptionHandler::setHandler()
+* added UndefinedMethodFatalErrorHandler
+* deprecated DummyException
+
+2.4.0
+-----
+
+ * added a DebugClassLoader able to wrap any autoloader providing a findFile method
+ * improved error messages for not found classes and functions
+
 2.3.0
 -----
 

Debug.php

@@ -11,8 +11,6 @@
 
 namespace Symfony\Component\Debug;
 
-use Symfony\Component\ClassLoader\DebugClassLoader;
-
 /**
  * Registers all the debug tools.
  *
@@ -25,15 +23,12 @@ 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 $displayErrors       Whether to display errors (for development) or just log them (for production)
      */
-    public static function enable($errorReportingLevel = null, $displayErrors = true)
+    public static function enable($errorReportingLevel = E_ALL, $displayErrors = true)
     {
         if (static::$enabled) {
             return;
@@ -41,18 +36,25 @@ class Debug
 
         static::$enabled = true;
 
-        error_reporting(-1);
+        if (null !== $errorReportingLevel) {
+            error_reporting($errorReportingLevel);
+        } else {
+            error_reporting(E_ALL);
+        }
 
-        ErrorHandler::register($errorReportingLevel, $displayErrors);
-        if ('cli' !== php_sapi_name()) {
+        if (!\in_array(\PHP_SAPI, ['cli', 'phpdbg'], true)) {
+            ini_set('display_errors', 0);
             ExceptionHandler::register();
-        // CLI - display errors only if they're not already logged to STDERR
-        } elseif ($displayErrors && (!ini_get('log_errors') || ini_get('error_log'))) {
+        } elseif ($displayErrors && (!filter_var(ini_get('log_errors'), FILTER_VALIDATE_BOOLEAN) || ini_get('error_log'))) {
+            // CLI - display errors only if they're not already logged to STDERR
             ini_set('display_errors', 1);
         }
-
-        if (class_exists('Symfony\Component\ClassLoader\DebugClassLoader')) {
-            DebugClassLoader::enable();
+        if ($displayErrors) {
+            ErrorHandler::register(new ErrorHandler(new BufferingLogger()));
+        } else {
+            ErrorHandler::register()->throwAt(0, true);
         }
+
+        DebugClassLoader::enable();
     }
 }

DebugClassLoader.php

@@ -0,0 +1,455 @@
+<?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;
+
+/**
+ * Autoloader checking if the class is really defined in the file found.
+ *
+ * The ClassLoader will wrap all registered autoloaders
+ * and will throw an exception if a file is found but does
+ * not declare the class.
+ *
+ * @author Fabien Potencier <fabien@symfony.com>
+ * @author Christophe Coevoet <stof@notk.org>
+ * @author Nicolas Grekas <p@tchwork.com>
+ */
+class DebugClassLoader
+{
+    private $classLoader;
+    private $isFinder;
+    private $loaded = [];
+    private static $caseCheck;
+    private static $checkedClasses = [];
+    private static $final = [];
+    private static $finalMethods = [];
+    private static $deprecated = [];
+    private static $internal = [];
+    private static $internalMethods = [];
+    private static $php7Reserved = ['int' => 1, 'float' => 1, 'bool' => 1, 'string' => 1, 'true' => 1, 'false' => 1, 'null' => 1];
+    private static $darwinCache = ['/' => ['/', []]];
+
+    public function __construct(callable $classLoader)
+    {
+        $this->classLoader = $classLoader;
+        $this->isFinder = \is_array($classLoader) && method_exists($classLoader[0], 'findFile');
+
+        if (!isset(self::$caseCheck)) {
+            $file = file_exists(__FILE__) ? __FILE__ : rtrim(realpath('.'), \DIRECTORY_SEPARATOR);
+            $i = strrpos($file, \DIRECTORY_SEPARATOR);
+            $dir = substr($file, 0, 1 + $i);
+            $file = substr($file, 1 + $i);
+            $test = strtoupper($file) === $file ? strtolower($file) : strtoupper($file);
+            $test = realpath($dir.$test);
+
+            if (false === $test || false === $i) {
+                // filesystem is case sensitive
+                self::$caseCheck = 0;
+            } elseif (substr($test, -\strlen($file)) === $file) {
+                // filesystem is case insensitive and realpath() normalizes the case of characters
+                self::$caseCheck = 1;
+            } elseif (false !== stripos(PHP_OS, 'darwin')) {
+                // on MacOSX, HFS+ is case insensitive but realpath() doesn't normalize the case of characters
+                self::$caseCheck = 2;
+            } else {
+                // filesystem case checks failed, fallback to disabling them
+                self::$caseCheck = 0;
+            }
+        }
+    }
+
+    /**
+     * Gets the wrapped class loader.
+     *
+     * @return callable The wrapped class loader
+     */
+    public function getClassLoader()
+    {
+        return $this->classLoader;
+    }
+
+    /**
+     * Wraps all autoloaders.
+     */
+    public static function enable()
+    {
+        // Ensures we don't hit https://bugs.php.net/42098
+        class_exists('Symfony\Component\Debug\ErrorHandler');
+        class_exists('Psr\Log\LogLevel');
+
+        if (!\is_array($functions = spl_autoload_functions())) {
+            return;
+        }
+
+        foreach ($functions as $function) {
+            spl_autoload_unregister($function);
+        }
+
+        foreach ($functions as $function) {
+            if (!\is_array($function) || !$function[0] instanceof self) {
+                $function = [new static($function), 'loadClass'];
+            }
+
+            spl_autoload_register($function);
+        }
+    }
+
+    /**
+     * Disables the wrapping.
+     */
+    public static function disable()
+    {
+        if (!\is_array($functions = spl_autoload_functions())) {
+            return;
+        }
+
+        foreach ($functions as $function) {
+            spl_autoload_unregister($function);
+        }
+
+        foreach ($functions as $function) {
+            if (\is_array($function) && $function[0] instanceof self) {
+                $function = $function[0]->getClassLoader();
+            }
+
+            spl_autoload_register($function);
+        }
+    }
+
+    /**
+     * @return string|null
+     */
+    public function findFile($class)
+    {
+        return $this->isFinder ? $this->classLoader[0]->findFile($class) ?: null : null;
+    }
+
+    /**
+     * Loads the given class or interface.
+     *
+     * @param string $class The name of the class
+     *
+     * @throws \RuntimeException
+     */
+    public function loadClass($class)
+    {
+        $e = error_reporting(error_reporting() | E_PARSE | E_ERROR | E_CORE_ERROR | E_COMPILE_ERROR);
+
+        try {
+            if ($this->isFinder && !isset($this->loaded[$class])) {
+                $this->loaded[$class] = true;
+                if (!$file = $this->classLoader[0]->findFile($class) ?: false) {
+                    // no-op
+                } elseif (\function_exists('opcache_is_script_cached') && @opcache_is_script_cached($file)) {
+                    include $file;
+
+                    return;
+                } elseif (false === include $file) {
+                    return;
+                }
+            } else {
+                \call_user_func($this->classLoader, $class);
+                $file = false;
+            }
+        } finally {
+            error_reporting($e);
+        }
+
+        $this->checkClass($class, $file);
+    }
+
+    private function checkClass($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));
+            }
+
+            $deprecations = $this->checkAnnotations($refl, $name);
+
+            if (isset(self::$php7Reserved[strtolower($refl->getShortName())])) {
+                $deprecations[] = sprintf('The "%s" class uses the reserved name "%s", it will break on PHP 7 and higher', $name, $refl->getShortName());
+            }
+
+            foreach ($deprecations as $message) {
+                @trigger_error($message, E_USER_DEPRECATED);
+            }
+        }
+
+        if (!$file) {
+            return;
+        }
+
+        if (!$exists) {
+            if (false !== strpos($class, '/')) {
+                throw new \RuntimeException(sprintf('Trying to autoload a class with an invalid name "%s". Be careful that the namespace separator is "\" in PHP, not "/".', $class));
+            }
+
+            throw new \RuntimeException(sprintf('The autoloader expected class "%s" to be defined in file "%s". The file was found but the class was not in it, the class name or namespace probably has a typo.', $class, $file));
+        }
+
+        if (self::$caseCheck && $message = $this->checkCase($refl, $file, $class)) {
+            throw new \RuntimeException(sprintf('Case mismatch between class and real file names: "%s" vs "%s" in "%s".', $message[0], $message[1], $message[2]));
+        }
+    }
+
+    public function checkAnnotations(\ReflectionClass $refl, $class)
+    {
+        $deprecations = [];
+
+        // Don't trigger deprecations for classes in the same vendor
+        if (2 > $len = 1 + (strpos($class, '\\') ?: strpos($class, '_'))) {
+            $len = 0;
+            $ns = '';
+        } else {
+            $ns = str_replace('_', '\\', substr($class, 0, $len));
+        }
+
+        // Detect annotations on the class
+        if (false !== $doc = $refl->getDocComment()) {
+            foreach (['final', 'deprecated', 'internal'] as $annotation) {
+                if (false !== strpos($doc, $annotation) && preg_match('#\n\s+\* @'.$annotation.'(?:( .+?)\.?)?\r?\n\s+\*(?: @|/$|\r?\n)#s', $doc, $notice)) {
+                    self::${$annotation}[$class] = isset($notice[1]) ? preg_replace('#\.?\r?\n( \*)? *(?= |\r?\n|$)#', '', $notice[1]) : '';
+                }
+            }
+        }
+
+        $parent = get_parent_class($class);
+        $parentAndOwnInterfaces = $this->getOwnInterfaces($class, $parent);
+        if ($parent) {
+            $parentAndOwnInterfaces[$parent] = $parent;
+
+            if (!isset(self::$checkedClasses[$parent])) {
+                $this->checkClass($parent);
+            }
+
+            if (isset(self::$final[$parent])) {
+                $deprecations[] = 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], $class);
+            }
+        }
+
+        // Detect if the parent is annotated
+        foreach ($parentAndOwnInterfaces + class_uses($class, false) as $use) {
+            if (!isset(self::$checkedClasses[$use])) {
+                $this->checkClass($use);
+            }
+            if (isset(self::$deprecated[$use]) && strncmp($ns, str_replace('_', '\\', $use), $len) && !isset(self::$deprecated[$class])) {
+                $type = class_exists($class, false) ? 'class' : (interface_exists($class, false) ? 'interface' : 'trait');
+                $verb = class_exists($use, false) || interface_exists($class, false) ? 'extends' : (interface_exists($use, false) ? 'implements' : 'uses');
+
+                $deprecations[] = sprintf('The "%s" %s %s "%s" that is deprecated%s.', $class, $type, $verb, $use, self::$deprecated[$use]);
+            }
+            if (isset(self::$internal[$use]) && strncmp($ns, str_replace('_', '\\', $use), $len)) {
+                $deprecations[] = 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], $class);
+            }
+        }
+
+        if (trait_exists($class)) {
+            return $deprecations;
+        }
+
+        // Inherit @final and @internal annotations for methods
+        self::$finalMethods[$class] = [];
+        self::$internalMethods[$class] = [];
+        foreach ($parentAndOwnInterfaces as $use) {
+            foreach (['finalMethods', 'internalMethods'] as $property) {
+                if (isset(self::${$property}[$use])) {
+                    self::${$property}[$class] = self::${$property}[$class] ? self::${$property}[$use] + self::${$property}[$class] : self::${$property}[$use];
+                }
+            }
+        }
+
+        foreach ($refl->getMethods(\ReflectionMethod::IS_PUBLIC | \ReflectionMethod::IS_PROTECTED) as $method) {
+            if ($method->class !== $class) {
+                continue;
+            }
+
+            if ($parent && isset(self::$finalMethods[$parent][$method->name])) {
+                list($declaringClass, $message) = self::$finalMethods[$parent][$method->name];
+                $deprecations[] = 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, $class);
+            }
+
+            if (isset(self::$internalMethods[$class][$method->name])) {
+                list($declaringClass, $message) = self::$internalMethods[$class][$method->name];
+                if (strncmp($ns, $declaringClass, $len)) {
+                    $deprecations[] = 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, $class);
+                }
+            }
+
+            // Detect method annotations
+            if (false === $doc = $method->getDocComment()) {
+                continue;
+            }
+
+            foreach (['final', 'internal'] as $annotation) {
+                if (false !== strpos($doc, $annotation) && preg_match('#\n\s+\* @'.$annotation.'(?:( .+?)\.?)?\r?\n\s+\*(?: @|/$|\r?\n)#s', $doc, $notice)) {
+                    $message = isset($notice[1]) ? preg_replace('#\.?\r?\n( \*)? *(?= |\r?\n|$)#', '', $notice[1]) : '';
+                    self::${$annotation.'Methods'}[$class][$method->name] = [$class, $message];
+                }
+            }
+        }
+
+        return $deprecations;
+    }
+
+    /**
+     * @param string $file
+     * @param string $class
+     *
+     * @return array|null
+     */
+    public function checkCase(\ReflectionClass $refl, $file, $class)
+    {
+        $real = explode('\\', $class.strrchr($file, '.'));
+        $tail = explode(\DIRECTORY_SEPARATOR, str_replace('/', \DIRECTORY_SEPARATOR, $file));
+
+        $i = \count($tail) - 1;
+        $j = \count($real) - 1;
+
+        while (isset($tail[$i], $real[$j]) && $tail[$i] === $real[$j]) {
+            --$i;
+            --$j;
+        }
+
+        array_splice($tail, 0, $i + 1);
+
+        if (!$tail) {
+            return null;
+        }
+
+        $tail = \DIRECTORY_SEPARATOR.implode(\DIRECTORY_SEPARATOR, $tail);
+        $tailLen = \strlen($tail);
+        $real = $refl->getFileName();
+
+        if (2 === self::$caseCheck) {
+            $real = $this->darwinRealpath($real);
+        }
+
+        if (0 === substr_compare($real, $tail, -$tailLen, $tailLen, true)
+            && 0 !== substr_compare($real, $tail, -$tailLen, $tailLen, false)
+        ) {
+            return [substr($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)
+    {
+        $i = 1 + strrpos($real, '/');
+        $file = substr($real, $i);
+        $real = substr($real, 0, $i);
+
+        if (isset(self::$darwinCache[$real])) {
+            $kDir = $real;
+        } else {
+            $kDir = strtolower($real);
+
+            if (isset(self::$darwinCache[$kDir])) {
+                $real = self::$darwinCache[$kDir][0];
+            } else {
+                $dir = getcwd();
+                chdir($real);
+                $real = getcwd().'/';
+                chdir($dir);
+
+                $dir = $real;
+                $k = $kDir;
+                $i = \strlen($dir) - 1;
+                while (!isset(self::$darwinCache[$k])) {
+                    self::$darwinCache[$k] = [$dir, []];
+                    self::$darwinCache[$dir] = &self::$darwinCache[$k];
+
+                    while ('/' !== $dir[--$i]) {
+                    }
+                    $k = substr($k, 0, ++$i);
+                    $dir = substr($dir, 0, $i--);
+                }
+            }
+        }
+
+        $dirFiles = self::$darwinCache[$kDir][1];
+
+        if (!isset($dirFiles[$file]) && ') : eval()\'d code' === substr($file, -17)) {
+            // Get the file name from "file_name.php(123) : eval()'d code"
+            $file = substr($file, 0, strrpos($file, '(', -17));
+        }
+
+        if (isset($dirFiles[$file])) {
+            return $real.$dirFiles[$file];
+        }
+
+        $kFile = strtolower($file);
+
+        if (!isset($dirFiles[$kFile])) {
+            foreach (scandir($real, 2) as $f) {
+                if ('.' !== $f[0]) {
+                    $dirFiles[$f] = $f;
+                    if ($f === $file) {
+                        $kFile = $k = $file;
+                    } elseif ($f !== $k = strtolower($f)) {
+                        $dirFiles[$k] = $f;
+                    }
+                }
+            }
+            self::$darwinCache[$kDir][1] = $dirFiles;
+        }
+
+        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)
+    {
+        $ownInterfaces = class_implements($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;
+    }
+}

ErrorHandler.php

@@ -11,196 +11,777 @@
 
 namespace Symfony\Component\Debug;
 
-use Symfony\Component\Debug\Exception\FatalErrorException;
-use Symfony\Component\Debug\Exception\ContextErrorException;
-use Symfony\Component\Debug\Exception\DummyException;
 use Psr\Log\LoggerInterface;
+use Psr\Log\LogLevel;
+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\ClassNotFoundFatalErrorHandler;
+use Symfony\Component\Debug\FatalErrorHandler\FatalErrorHandlerInterface;
+use Symfony\Component\Debug\FatalErrorHandler\UndefinedFunctionFatalErrorHandler;
+use Symfony\Component\Debug\FatalErrorHandler\UndefinedMethodFatalErrorHandler;
 
 /**
- * ErrorHandler.
+ * A generic ErrorHandler for the PHP engine.
  *
- * @author Fabien Potencier <fabien@symfony.com>
- * @author Konstantin Myakshin <koc-dp@yandex.ru>
+ * Provides five bit fields that control how errors are handled:
+ * - 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
+ * - screamedErrors: never @-silenced errors
+ *
+ * Each error level can be logged by a dedicated PSR-3 logger object.
+ * Screaming only applies to logging.
+ * Throwing takes precedence over logging.
+ * Uncaught exceptions are logged as E_ERROR.
+ * E_DEPRECATED and E_USER_DEPRECATED levels never throw.
+ * E_RECOVERABLE_ERROR and E_USER_ERROR levels always throw.
+ * Non catchable errors that can be detected at shutdown time are logged when the scream bit field allows so.
+ * As errors have a performance cost, repeated errors are all logged, so that the developer
+ * 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
 {
-    const TYPE_DEPRECATION = -100;
-
-    private $levels = array(
-        E_WARNING => 'Warning',
-        E_NOTICE => 'Notice',
-        E_USER_ERROR => 'User Error',
-        E_USER_WARNING => 'User Warning',
-        E_USER_NOTICE => 'User Notice',
-        E_STRICT => 'Runtime Notice',
-        E_RECOVERABLE_ERROR => 'Catchable Fatal Error',
+    private $levels = [
         E_DEPRECATED => 'Deprecated',
         E_USER_DEPRECATED => 'User Deprecated',
+        E_NOTICE => 'Notice',
+        E_USER_NOTICE => 'User Notice',
+        E_STRICT => 'Runtime Notice',
+        E_WARNING => 'Warning',
+        E_USER_WARNING => 'User Warning',
+        E_COMPILE_WARNING => 'Compile Warning',
+        E_CORE_WARNING => 'Core Warning',
+        E_USER_ERROR => 'User Error',
+        E_RECOVERABLE_ERROR => 'Catchable Fatal Error',
+        E_COMPILE_ERROR => 'Compile Error',
+        E_PARSE => 'Parse Error',
         E_ERROR => 'Error',
         E_CORE_ERROR => 'Core Error',
-        E_COMPILE_ERROR => 'Compile Error',
-        E_PARSE => 'Parse',
-    );
+    ];
 
-    private $level;
+    private $loggers = [
+        E_DEPRECATED => [null, LogLevel::INFO],
+        E_USER_DEPRECATED => [null, LogLevel::INFO],
+        E_NOTICE => [null, LogLevel::WARNING],
+        E_USER_NOTICE => [null, LogLevel::WARNING],
+        E_STRICT => [null, LogLevel::WARNING],
+        E_WARNING => [null, LogLevel::WARNING],
+        E_USER_WARNING => [null, LogLevel::WARNING],
+        E_COMPILE_WARNING => [null, LogLevel::WARNING],
+        E_CORE_WARNING => [null, LogLevel::WARNING],
+        E_USER_ERROR => [null, LogLevel::CRITICAL],
+        E_RECOVERABLE_ERROR => [null, LogLevel::CRITICAL],
+        E_COMPILE_ERROR => [null, LogLevel::CRITICAL],
+        E_PARSE => [null, LogLevel::CRITICAL],
+        E_ERROR => [null, LogLevel::CRITICAL],
+        E_CORE_ERROR => [null, LogLevel::CRITICAL],
+    ];
 
-    private $reservedMemory;
+    private $thrownErrors = 0x1FFF; // E_ALL - E_DEPRECATED - E_USER_DEPRECATED
+    private $scopedErrors = 0x1FFF; // E_ALL - E_DEPRECATED - E_USER_DEPRECATED
+    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 $displayErrors;
+    private $isRecursive = 0;
+    private $isRoot = false;
+    private $exceptionHandler;
+    private $bootstrappingLogger;
 
-    /**
-     * @var LoggerInterface[] Loggers for channels
-     */
-    private static $loggers = array();
+    private static $reservedMemory;
+    private static $stackedErrors = [];
+    private static $stackedErrorLevels = [];
+    private static $toStringException = null;
+    private static $silencedErrorCache = [];
+    private static $silencedErrorCount = 0;
+    private static $exitCode = 0;
 
     /**
      * Registers the error handler.
      *
-     * @param int  $level         The level at which the conversion to Exception is done (null to use the error_reporting() value and 0 to disable)
-     * @param bool $displayErrors Display errors (for dev environment) or just log they (production usage)
+     * @param self|null $handler The handler to register
+     * @param bool      $replace Whether to replace or not any existing handler
      *
-     * @return ErrorHandler The registered error handler
+     * @return self The registered error handler
      */
-    public static function register($level = null, $displayErrors = true)
+    public static function register(self $handler = null, $replace = true)
     {
-        $handler = new static();
-        $handler->setLevel($level);
-        $handler->setDisplayErrors($displayErrors);
+        if (null === self::$reservedMemory) {
+            self::$reservedMemory = str_repeat('x', 10240);
+            register_shutdown_function(__CLASS__.'::handleFatalError');
+        }
 
-        ini_set('display_errors', 0);
-        set_error_handler(array($handler, 'handle'));
-        register_shutdown_function(array($handler, 'handleFatal'));
-        $handler->reservedMemory = str_repeat('x', 10240);
+        if ($handlerIsNew = null === $handler) {
+            $handler = new static();
+        }
+
+        if (null === $prev = set_error_handler([$handler, 'handleError'])) {
+            restore_error_handler();
+            // Specifying the error types earlier would expose us to https://bugs.php.net/63206
+            set_error_handler([$handler, 'handleError'], $handler->thrownErrors | $handler->loggedErrors);
+            $handler->isRoot = true;
+        }
+
+        if ($handlerIsNew && \is_array($prev) && $prev[0] instanceof self) {
+            $handler = $prev[0];
+            $replace = false;
+        }
+        if (!$replace && $prev) {
+            restore_error_handler();
+            $handlerIsRegistered = \is_array($prev) && $handler === $prev[0];
+        } else {
+            $handlerIsRegistered = true;
+        }
+        if (\is_array($prev = set_exception_handler([$handler, 'handleException'])) && $prev[0] instanceof self) {
+            restore_exception_handler();
+            if (!$handlerIsRegistered) {
+                $handler = $prev[0];
+            } elseif ($handler !== $prev[0] && $replace) {
+                set_exception_handler([$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);
 
         return $handler;
     }
 
-    public function setLevel($level)
+    public function __construct(BufferingLogger $bootstrappingLogger = null)
     {
-        $this->level = null === $level ? error_reporting() : $level;
-    }
-
-    public function setDisplayErrors($displayErrors)
-    {
-        $this->displayErrors = $displayErrors;
-    }
-
-    public static function setLogger(LoggerInterface $logger, $channel = 'deprecation')
-    {
-        self::$loggers[$channel] = $logger;
+        if ($bootstrappingLogger) {
+            $this->bootstrappingLogger = $bootstrappingLogger;
+            $this->setDefaultLogger($bootstrappingLogger);
+        }
+        $this->traceReflector = new \ReflectionProperty('Exception', 'trace');
+        $this->traceReflector->setAccessible(true);
     }
 
     /**
-     * @throws ContextErrorException When error_reporting returns error
+     * 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            $replace Whether to replace or not any existing logger
      */
-    public function handle($level, $message, $file = 'unknown', $line = 0, $context = array())
+    public function setDefaultLogger(LoggerInterface $logger, $levels = E_ALL, $replace = false)
     {
-        if (0 === $this->level) {
-            return false;
+        $loggers = [];
+
+        if (\is_array($levels)) {
+            foreach ($levels as $type => $logLevel) {
+                if (empty($this->loggers[$type][0]) || $replace || $this->loggers[$type][0] === $this->bootstrappingLogger) {
+                    $loggers[$type] = [$logger, $logLevel];
+                }
+            }
+        } else {
+            if (null === $levels) {
+                $levels = E_ALL;
+            }
+            foreach ($this->loggers as $type => $log) {
+                if (($type & $levels) && (empty($log[0]) || $replace || $log[0] === $this->bootstrappingLogger)) {
+                    $log[0] = $logger;
+                    $loggers[$type] = $log;
+                }
+            }
         }
 
-        if ($level & (E_USER_DEPRECATED | E_DEPRECATED)) {
-            if (isset(self::$loggers['deprecation'])) {
-                if (PHP_VERSION_ID < 50400) {
-                    $stack = array_map(
-                        function ($row) {
-                            unset($row['args']);
+        $this->setLoggers($loggers);
+    }
 
-                            return $row;
-                        },
-                        array_slice(debug_backtrace(false), 0, 10)
-                    );
-                } else {
-                    $stack = debug_backtrace(DEBUG_BACKTRACE_IGNORE_ARGS, 10);
-                }
+    /**
+     * Sets a logger for each error level.
+     *
+     * @param array $loggers Error levels to [LoggerInterface|null, LogLevel::*] map
+     *
+     * @return array The previous map
+     *
+     * @throws \InvalidArgumentException
+     */
+    public function setLoggers(array $loggers)
+    {
+        $prevLogged = $this->loggedErrors;
+        $prev = $this->loggers;
+        $flush = [];
 
-                self::$loggers['deprecation']->warning($message, array('type' => self::TYPE_DEPRECATION, 'stack' => $stack));
+        foreach ($loggers as $type => $log) {
+            if (!isset($prev[$type])) {
+                throw new \InvalidArgumentException('Unknown error type: '.$type);
             }
+            if (!\is_array($log)) {
+                $log = [$log];
+            } elseif (!\array_key_exists(0, $log)) {
+                throw new \InvalidArgumentException('No logger provided');
+            }
+            if (null === $log[0]) {
+                $this->loggedErrors &= ~$type;
+            } elseif ($log[0] instanceof LoggerInterface) {
+                $this->loggedErrors |= $type;
+            } else {
+                throw new \InvalidArgumentException('Invalid logger provided');
+            }
+            $this->loggers[$type] = $log + $prev[$type];
+
+            if ($this->bootstrappingLogger && $prev[$type][0] === $this->bootstrappingLogger) {
+                $flush[$type] = $type;
+            }
+        }
+        $this->reRegister($prevLogged | $this->thrownErrors);
+
+        if ($flush) {
+            foreach ($this->bootstrappingLogger->cleanLogs() as $log) {
+                $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]) {
+                    $this->loggers[$type][0]->log($this->loggers[$type][1], $log[1], $log[2]);
+                }
+            }
+        }
+
+        return $prev;
+    }
+
+    /**
+     * Sets a user exception handler.
+     *
+     * @param callable $handler A handler that will be called on Exception
+     *
+     * @return callable|null The previous exception handler
+     */
+    public function setExceptionHandler(callable $handler = null)
+    {
+        $prev = $this->exceptionHandler;
+        $this->exceptionHandler = $handler;
+
+        return $prev;
+    }
+
+    /**
+     * Sets the PHP error levels that throw an exception when a PHP error occurs.
+     *
+     * @param int  $levels  A bit field of E_* constants for thrown errors
+     * @param bool $replace Replace or amend the previous value
+     *
+     * @return int The previous value
+     */
+    public function throwAt($levels, $replace = false)
+    {
+        $prev = $this->thrownErrors;
+        $this->thrownErrors = ($levels | E_RECOVERABLE_ERROR | E_USER_ERROR) & ~E_USER_DEPRECATED & ~E_DEPRECATED;
+        if (!$replace) {
+            $this->thrownErrors |= $prev;
+        }
+        $this->reRegister($prev | $this->loggedErrors);
+
+        return $prev;
+    }
+
+    /**
+     * Sets the PHP error levels for which local variables are preserved.
+     *
+     * @param int  $levels  A bit field of E_* constants for scoped errors
+     * @param bool $replace Replace or amend the previous value
+     *
+     * @return int The previous value
+     */
+    public function scopeAt($levels, $replace = false)
+    {
+        $prev = $this->scopedErrors;
+        $this->scopedErrors = (int) $levels;
+        if (!$replace) {
+            $this->scopedErrors |= $prev;
+        }
+
+        return $prev;
+    }
+
+    /**
+     * Sets the PHP error levels for which the stack trace is preserved.
+     *
+     * @param int  $levels  A bit field of E_* constants for traced errors
+     * @param bool $replace Replace or amend the previous value
+     *
+     * @return int The previous value
+     */
+    public function traceAt($levels, $replace = false)
+    {
+        $prev = $this->tracedErrors;
+        $this->tracedErrors = (int) $levels;
+        if (!$replace) {
+            $this->tracedErrors |= $prev;
+        }
+
+        return $prev;
+    }
+
+    /**
+     * Sets the error levels where the @-operator is ignored.
+     *
+     * @param int  $levels  A bit field of E_* constants for screamed errors
+     * @param bool $replace Replace or amend the previous value
+     *
+     * @return int The previous value
+     */
+    public function screamAt($levels, $replace = false)
+    {
+        $prev = $this->screamedErrors;
+        $this->screamedErrors = (int) $levels;
+        if (!$replace) {
+            $this->screamedErrors |= $prev;
+        }
+
+        return $prev;
+    }
+
+    /**
+     * Re-registers as a PHP error handler if levels changed.
+     */
+    private function reRegister($prev)
+    {
+        if ($prev !== $this->thrownErrors | $this->loggedErrors) {
+            $handler = set_error_handler('var_dump');
+            $handler = \is_array($handler) ? $handler[0] : null;
+            restore_error_handler();
+            if ($handler === $this) {
+                restore_error_handler();
+                if ($this->isRoot) {
+                    set_error_handler([$this, 'handleError'], $this->thrownErrors | $this->loggedErrors);
+                } else {
+                    set_error_handler([$this, 'handleError']);
+                }
+            }
+        }
+    }
+
+    /**
+     * Handles errors by filtering then logging them according to the configured bit fields.
+     *
+     * @param int    $type    One of the E_* constants
+     * @param string $message
+     * @param string $file
+     * @param int    $line
+     *
+     * @return bool Returns false when no handling happens so that the PHP engine can handle the error itself
+     *
+     * @throws \ErrorException When $this->thrownErrors requests so
+     *
+     * @internal
+     */
+    public function handleError($type, $message, $file, $line)
+    {
+        if (\PHP_VERSION_ID >= 70300 && E_WARNING === $type && '"' === $message[0] && false !== strpos($message, '" targeting switch is equivalent to "break')) {
+            $type = E_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 !$silenced && $type && $log;
+        }
+        $scope = $this->scopedErrors & $type;
+
+        if (4 < $numArgs = \func_num_args()) {
+            $context = $scope ? (func_get_arg(4) ?: []) : [];
+            $backtrace = 5 < $numArgs ? func_get_arg(5) : null; // defined on HHVM
+        } else {
+            $context = [];
+            $backtrace = null;
+        }
+
+        if (isset($context['GLOBALS']) && $scope) {
+            $e = $context;                  // Whatever the signature of the method,
+            unset($e['GLOBALS'], $context); // $context is always a reference in 5.3
+            $context = $e;
+        }
+
+        if (null !== $backtrace && $type & E_ERROR) {
+            // E_ERROR fatal errors are triggered on HHVM when
+            // hhvm.error_handling.call_user_handler_on_fatals=1
+            // which is the way to get their backtrace.
+            $this->handleFatalError(compact('type', 'message', 'file', 'line', 'backtrace'));
 
             return true;
         }
 
-        if ($this->displayErrors && error_reporting() & $level && $this->level & $level) {
-            // make sure the ContextErrorException class is loaded (https://bugs.php.net/bug.php?id=65322)
-            if (!class_exists('Symfony\Component\Debug\Exception\ContextErrorException')) {
-                require __DIR__.'/Exception/ContextErrorException.php';
-            }
-            if (!class_exists('Symfony\Component\Debug\Exception\FlattenException')) {
-                require __DIR__.'/Exception/FlattenException.php';
+        $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) : [];
+                $errorAsException = new SilencedErrorContext($type, $file, $line, $lightTrace);
+            } elseif (isset(self::$silencedErrorCache[$id][$message])) {
+                $lightTrace = null;
+                $errorAsException = self::$silencedErrorCache[$id][$message];
+                ++$errorAsException->count;
+            } else {
+                $lightTrace = [];
+                $errorAsException = null;
             }
 
-            if (PHP_VERSION_ID < 50400 && isset($context['GLOBALS']) && is_array($context)) {
-                unset($context['GLOBALS']);
+            if (100 < ++self::$silencedErrorCount) {
+                self::$silencedErrorCache = $lightTrace = [];
+                self::$silencedErrorCount = 1;
+            }
+            if ($errorAsException) {
+                self::$silencedErrorCache[$id][$message] = $errorAsException;
+            }
+            if (null === $lightTrace) {
+                return true;
+            }
+        } else {
+            if ($scope) {
+                $errorAsException = new ContextErrorException($logMessage, 0, $type, $file, $line, $context);
+            } else {
+                $errorAsException = new \ErrorException($logMessage, 0, $type, $file, $line);
             }
 
-            $exception = new ContextErrorException(sprintf('%s: %s in %s line %d', isset($this->levels[$level]) ? $this->levels[$level] : $level, $message, $file, $line), 0, $level, $file, $line, $context);
+            // Clean the trace by removing function arguments and the first frames added by the error handler itself.
+            if ($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, []);
+            }
+        }
 
-            // Exceptions thrown from error handlers are sometimes not caught by the exception
-            // handler, so we invoke it directly (https://bugs.php.net/bug.php?id=54275)
-            $exceptionHandler = set_exception_handler(function () {});
+        if ($throw) {
+            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']
+                        && '->' === $backtrace[$i]['type']
+                        && !isset($backtrace[$i - 1]['class'])
+                        && ('trigger_error' === $backtrace[$i - 1]['function'] || 'user_error' === $backtrace[$i - 1]['function'])
+                    ) {
+                        // Here, we know trigger_error() has been called from __toString().
+                        // HHVM is fine with throwing from __toString() but PHP triggers a fatal error instead.
+                        // A small convention allows working around the limitation:
+                        // given a caught $e exception in __toString(), quitting the method with
+                        // `return trigger_error($e, E_USER_ERROR);` allows this error handler
+                        // to make $e get through the __toString() barrier.
+
+                        foreach ($context as $e) {
+                            if (($e instanceof \Exception || $e instanceof \Throwable) && $e->__toString() === $message) {
+                                if (1 === $i) {
+                                    // On HHVM
+                                    $errorAsException = $e;
+                                    break;
+                                }
+                                self::$toStringException = $e;
+
+                                return true;
+                            }
+                        }
+
+                        if (1 < $i) {
+                            // On PHP (not on HHVM), display the original error message instead of the default one.
+                            $this->handleException($errorAsException);
+
+                            // Stop the process by giving back the error to the native handler.
+                            return false;
+                        }
+                    }
+                }
+            }
+
+            throw $errorAsException;
+        }
+
+        if ($this->isRecursive) {
+            $log = 0;
+        } elseif (self::$stackedErrorLevels) {
+            self::$stackedErrors[] = [
+                $this->loggers[$type][0],
+                ($type & $level) ? $this->loggers[$type][1] : LogLevel::DEBUG,
+                $logMessage,
+                $errorAsException ? ['exception' => $errorAsException] : [],
+            ];
+        } else {
+            if (!\defined('HHVM_VERSION')) {
+                $currentErrorHandler = set_error_handler('var_dump');
+                restore_error_handler();
+            }
+
+            try {
+                $this->isRecursive = true;
+                $level = ($type & $level) ? $this->loggers[$type][1] : LogLevel::DEBUG;
+                $this->loggers[$type][0]->log($level, $logMessage, $errorAsException ? ['exception' => $errorAsException] : []);
+            } finally {
+                $this->isRecursive = false;
+
+                if (!\defined('HHVM_VERSION')) {
+                    set_error_handler($currentErrorHandler);
+                }
+            }
+        }
+
+        return !$silenced && $type && $log;
+    }
+
+    /**
+     * Handles an exception by logging then forwarding it to another handler.
+     *
+     * @param \Exception|\Throwable $exception An exception to handle
+     * @param array                 $error     An array as returned by error_get_last()
+     *
+     * @internal
+     */
+    public function handleException($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) || $exception instanceof FatalThrowableError) {
+            if ($exception instanceof FatalErrorException) {
+                if ($exception instanceof FatalThrowableError) {
+                    $error = [
+                        'type' => $type,
+                        'message' => $message = $exception->getMessage(),
+                        'file' => $exception->getFile(),
+                        'line' => $exception->getLine(),
+                    ];
+                } else {
+                    $message = 'Fatal '.$exception->getMessage();
+                }
+            } elseif ($exception instanceof \ErrorException) {
+                $message = 'Uncaught '.$exception->getMessage();
+            } else {
+                $message = 'Uncaught Exception: '.$exception->getMessage();
+            }
+        }
+        if ($this->loggedErrors & $type) {
+            try {
+                $this->loggers[$type][0]->log($this->loggers[$type][1], $message, ['exception' => $exception]);
+            } catch (\Exception $handlerException) {
+            } catch (\Throwable $handlerException) {
+            }
+        }
+        if ($exception instanceof FatalErrorException && !$exception instanceof OutOfMemoryException && $error) {
+            foreach ($this->getFatalErrorHandlers() as $handler) {
+                if ($e = $handler->handleError($error, $exception)) {
+                    $exception = $e;
+                    break;
+                }
+            }
+        }
+        $exceptionHandler = $this->exceptionHandler;
+        $this->exceptionHandler = null;
+        try {
+            if (null !== $exceptionHandler) {
+                $exceptionHandler($exception);
+
+                return;
+            }
+            $handlerException = $handlerException ?: $exception;
+        } catch (\Exception $handlerException) {
+        } catch (\Throwable $handlerException) {
+        }
+        if ($exception === $handlerException) {
+            self::$reservedMemory = null; // Disable the fatal error handler
+            throw $exception; // Give back $exception to the native handler
+        }
+        $this->handleException($handlerException);
+    }
+
+    /**
+     * Shutdown registered function for handling PHP fatal errors.
+     *
+     * @param array $error An array as returned by error_get_last()
+     *
+     * @internal
+     */
+    public static function handleFatalError(array $error = null)
+    {
+        if (null === self::$reservedMemory) {
+            return;
+        }
+
+        $handler = self::$reservedMemory = null;
+        $handlers = [];
+        $previousHandler = null;
+        $sameHandlerLimit = 10;
+
+        while (!\is_array($handler) || !$handler[0] instanceof self) {
+            $handler = set_exception_handler('var_dump');
             restore_exception_handler();
 
-            if (is_array($exceptionHandler) && $exceptionHandler[0] instanceof ExceptionHandler) {
-                $exceptionHandler[0]->handle($exception);
+            if (!$handler) {
+                break;
+            }
+            restore_exception_handler();
 
-                if (!class_exists('Symfony\Component\Debug\Exception\DummyException')) {
-                    require __DIR__.'/Exception/DummyException.php';
-                }
+            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 = [];
 
-                // we must stop the PHP script execution, as the exception has
-                // already been dealt with, so, let's throw an exception that
-                // will be caught by a dummy exception handler
-                set_exception_handler(function (\Exception $e) use ($exceptionHandler) {
-                    if (!$e instanceof DummyException) {
-                        // happens if our dummy exception is caught by a
-                        // catch-all from user code, in which case, let's the
-                        // current handler handle this "new" exception
-                        call_user_func($exceptionHandler, $e);
-                    }
-                });
+        if ($exit = null === $error) {
+            $error = error_get_last();
+        }
 
-                throw new DummyException();
+        try {
+            while (self::$stackedErrorLevels) {
+                static::unstackErrors();
+            }
+        } catch (\Exception $exception) {
+            // Handled below
+        } catch (\Throwable $exception) {
+            // Handled below
+        }
+
+        if ($error && $error['type'] &= E_PARSE | E_ERROR | E_CORE_ERROR | E_COMPILE_ERROR) {
+            // Let's not throw anymore but keep logging
+            $handler->throwAt(0, true);
+            $trace = isset($error['backtrace']) ? $error['backtrace'] : null;
+
+            if (0 === strpos($error['message'], 'Allowed memory') || 0 === strpos($error['message'], 'Out of memory')) {
+                $exception = new OutOfMemoryException($handler->levels[$error['type']].': '.$error['message'], 0, $error['type'], $error['file'], $error['line'], 2, false, $trace);
+            } else {
+                $exception = new FatalErrorException($handler->levels[$error['type']].': '.$error['message'], 0, $error['type'], $error['file'], $error['line'], 2, true, $trace);
             }
         }
 
-        return false;
+        try {
+            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); });
+        }
     }
 
-    public function handleFatal()
+    /**
+     * Configures the error handler for delayed handling.
+     * Ensures also that non-catchable fatal errors are never silenced.
+     *
+     * As shown by http://bugs.php.net/42098 and http://bugs.php.net/60724
+     * PHP has a compile stage where it behaves unusually. To workaround it,
+     * we plug an error handler that only stacks errors for later.
+     *
+     * 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()
     {
-        if (null === $error = error_get_last()) {
-            return;
+        @trigger_error('Support for stacking errors is deprecated since Symfony 3.4 and will be removed in 4.0.', E_USER_DEPRECATED);
+
+        self::$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) {
+            $errorReportingLevel = error_reporting($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($errorReportingLevel);
+            }
         }
 
-        $this->reservedMemory = '';
-        $type = $error['type'];
-        if (0 === $this->level || !in_array($type, array(E_ERROR, E_CORE_ERROR, E_COMPILE_ERROR, E_PARSE))) {
-            return;
+        if (empty(self::$stackedErrorLevels)) {
+            $errors = self::$stackedErrors;
+            self::$stackedErrors = [];
+
+            foreach ($errors as $error) {
+                $error[0]->log($error[1], $error[2], $error[3]);
+            }
+        }
+    }
+
+    /**
+     * Gets the fatal error handlers.
+     *
+     * Override this method if you want to define more fatal error handlers.
+     *
+     * @return FatalErrorHandlerInterface[] An array of FatalErrorHandlerInterface
+     */
+    protected function getFatalErrorHandlers()
+    {
+        return [
+            new UndefinedFunctionFatalErrorHandler(),
+            new UndefinedMethodFatalErrorHandler(),
+            new ClassNotFoundFatalErrorHandler(),
+        ];
+    }
+
+    private function cleanTrace($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']);
+            }
         }
 
-        if (isset(self::$loggers['emergency'])) {
-            $fatal = array(
-                'type' => $type,
-                'file' => $error['file'],
-                'line' => $error['line'],
-            );
-
-            self::$loggers['emergency']->emerg($error['message'], $fatal);
-        }
-
-        if (!$this->displayErrors) {
-            return;
-        }
-
-        // get current exception handler
-        $exceptionHandler = set_exception_handler(function () {});
-        restore_exception_handler();
-
-        if (is_array($exceptionHandler) && $exceptionHandler[0] instanceof ExceptionHandler) {
-            $level = isset($this->levels[$type]) ? $this->levels[$type] : $type;
-            $message = sprintf('%s: %s in %s line %d', $level, $error['message'], $error['file'], $error['line']);
-            $exception = new FatalErrorException($message, 0, $type, $error['file'], $error['line']);
-            $exceptionHandler[0]->handle($exception);
-        }
+        return $lightTrace;
     }
 }

Exception/ClassNotFoundException.php

@@ -0,0 +1,36 @@
+<?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;
+
+/**
+ * Class (or Trait or Interface) Not Found Exception.
+ *
+ * @author Konstanton Myakshin <koc-dp@yandex.ru>
+ */
+class ClassNotFoundException extends FatalErrorException
+{
+    public function __construct($message, \ErrorException $previous)
+    {
+        parent::__construct(
+            $message,
+            $previous->getCode(),
+            $previous->getSeverity(),
+            $previous->getFile(),
+            $previous->getLine(),
+            null,
+            true,
+            null,
+            $previous->getPrevious()
+        );
+        $this->setTrace($previous->getTrace());
+    }
+}

Exception/ContextErrorException.php

@@ -15,12 +15,14 @@ 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
 {
-    private $context = array();
+    private $context = [];
 
-    public function __construct($message, $code, $severity, $filename, $lineno, $context = array())
+    public function __construct($message, $code, $severity, $filename, $lineno, $context = [])
     {
         parent::__construct($message, $code, $severity, $filename, $lineno);
         $this->context = $context;
@@ -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;
     }
 }

Exception/FatalErrorException.php

@@ -9,28 +9,74 @@
  * file that was distributed with this source code.
  */
 
-namespace Symfony\Component\HttpKernel\Exception;
+namespace Symfony\Component\Debug\Exception;
 
 /**
  * Fatal Error Exception.
  *
  * @author Konstanton Myakshin <koc-dp@yandex.ru>
- *
- * @deprecated Deprecated in 2.3, to be removed in 3.0. Use the same class from the Debug component instead.
  */
 class FatalErrorException extends \ErrorException
 {
-}
-
-namespace Symfony\Component\Debug\Exception;
-
-use Symfony\Component\HttpKernel\Exception\FatalErrorException as LegacyFatalErrorException;
-
-/**
- * Fatal Error Exception.
- *
- * @author Konstanton Myakshin <koc-dp@yandex.ru>
- */
-class FatalErrorException extends LegacyFatalErrorException
-{
+    public function __construct($message, $code, $severity, $filename, $lineno, $traceOffset = null, $traceArgs = true, array $trace = null, $previous = null)
+    {
+        parent::__construct($message, $code, $severity, $filename, $lineno, $previous);
+
+        if (null !== $trace) {
+            if (!$traceArgs) {
+                foreach ($trace as &$frame) {
+                    unset($frame['args'], $frame['this'], $frame);
+                }
+            }
+
+            $this->setTrace($trace);
+        } elseif (null !== $traceOffset) {
+            if (\function_exists('xdebug_get_function_stack')) {
+                $trace = xdebug_get_function_stack();
+                if (0 < $traceOffset) {
+                    array_splice($trace, -$traceOffset);
+                }
+
+                foreach ($trace as &$frame) {
+                    if (!isset($frame['type'])) {
+                        // XDebug pre 2.1.1 doesn't currently set the call type key http://bugs.xdebug.org/view.php?id=695
+                        if (isset($frame['class'])) {
+                            $frame['type'] = '::';
+                        }
+                    } elseif ('dynamic' === $frame['type']) {
+                        $frame['type'] = '->';
+                    } elseif ('static' === $frame['type']) {
+                        $frame['type'] = '::';
+                    }
+
+                    // XDebug also has a different name for the parameters array
+                    if (!$traceArgs) {
+                        unset($frame['params'], $frame['args']);
+                    } elseif (isset($frame['params']) && !isset($frame['args'])) {
+                        $frame['args'] = $frame['params'];
+                        unset($frame['params']);
+                    }
+                }
+
+                unset($frame);
+                $trace = array_reverse($trace);
+            } elseif (\function_exists('symfony_debug_backtrace')) {
+                $trace = symfony_debug_backtrace();
+                if (0 < $traceOffset) {
+                    array_splice($trace, 0, $traceOffset);
+                }
+            } else {
+                $trace = [];
+            }
+
+            $this->setTrace($trace);
+        }
+    }
+
+    protected function setTrace($trace)
+    {
+        $traceReflector = new \ReflectionProperty('Exception', 'trace');
+        $traceReflector->setAccessible(true);
+        $traceReflector->setValue($this, $trace);
+    }
 }

Exception/FatalThrowableError.php

@@ -0,0 +1,45 @@
+<?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;
+
+/**
+ * Fatal Throwable Error.
+ *
+ * @author Nicolas Grekas <p@tchwork.com>
+ */
+class FatalThrowableError extends FatalErrorException
+{
+    public function __construct(\Throwable $e)
+    {
+        if ($e instanceof \ParseError) {
+            $message = 'Parse error: '.$e->getMessage();
+            $severity = E_PARSE;
+        } elseif ($e instanceof \TypeError) {
+            $message = 'Type error: '.$e->getMessage();
+            $severity = E_RECOVERABLE_ERROR;
+        } else {
+            $message = $e->getMessage();
+            $severity = E_ERROR;
+        }
+
+        \ErrorException::__construct(
+            $message,
+            $e->getCode(),
+            $severity,
+            $e->getFile(),
+            $e->getLine(),
+            $e->getPrevious()
+        );
+
+        $this->setTrace($e->getTrace());
+    }
+}

Exception/FlattenException.php

@@ -9,49 +9,9 @@
  * file that was distributed with this source code.
  */
 
-namespace Symfony\Component\HttpKernel\Exception;
-
-use Symfony\Component\Debug\Exception\FlattenException as DebugFlattenException;
-
-/**
- * FlattenException wraps a PHP Exception to be able to serialize it.
- *
- * Basically, this class removes all objects from the trace.
- *
- * @author Fabien Potencier <fabien@symfony.com>
- *
- * @deprecated Deprecated in 2.3, to be removed in 3.0. Use the same class from the Debug component instead.
- */
-class FlattenException
-{
-    private $handler;
-
-    public static function __callStatic($method, $args)
-    {
-        if (!method_exists('Symfony\Component\Debug\Exception\FlattenException', $method)) {
-            throw new \BadMethodCallException(sprintf('Call to undefined method %s::%s()', get_called_class(), $method));
-        }
-
-        return call_user_func_array(array('Symfony\Component\Debug\Exception\FlattenException', $method), $args);
-    }
-
-    public function __call($method, $args)
-    {
-        if (!isset($this->handler)) {
-            $this->handler = new DebugFlattenException();
-        }
-
-        if (!method_exists($this->handler, $method)) {
-            throw new \BadMethodCallException(sprintf('Call to undefined method %s::%s()', get_class($this), $method));
-        }
-
-        return call_user_func_array(array($this->handler, $method), $args);
-    }
-}
-
 namespace Symfony\Component\Debug\Exception;
 
-use Symfony\Component\HttpKernel\Exception\FlattenException as LegacyFlattenException;
+use Symfony\Component\HttpFoundation\Exception\RequestExceptionInterface;
 use Symfony\Component\HttpKernel\Exception\HttpExceptionInterface;
 
 /**
@@ -61,7 +21,7 @@ use Symfony\Component\HttpKernel\Exception\HttpExceptionInterface;
  *
  * @author Fabien Potencier <fabien@symfony.com>
  */
-class FlattenException extends LegacyFlattenException
+class FlattenException
 {
     private $message;
     private $code;
@@ -73,7 +33,7 @@ class FlattenException extends LegacyFlattenException
     private $file;
     private $line;
 
-    public static function create(\Exception $exception, $statusCode = null, array $headers = array())
+    public static function create(\Exception $exception, $statusCode = null, array $headers = [])
     {
         $e = new static();
         $e->setMessage($exception->getMessage());
@@ -82,6 +42,8 @@ class FlattenException extends LegacyFlattenException
         if ($exception instanceof HttpExceptionInterface) {
             $statusCode = $exception->getStatusCode();
             $headers = array_merge($headers, $exception->getHeaders());
+        } elseif ($exception instanceof RequestExceptionInterface) {
+            $statusCode = 400;
         }
 
         if (null === $statusCode) {
@@ -91,11 +53,16 @@ class FlattenException extends LegacyFlattenException
         $e->setStatusCode($statusCode);
         $e->setHeaders($headers);
         $e->setTraceFromException($exception);
-        $e->setClass(get_class($exception));
+        $e->setClass(\get_class($exception));
         $e->setFile($exception->getFile());
         $e->setLine($exception->getLine());
-        if ($exception->getPrevious()) {
-            $e->setPrevious(static::create($exception->getPrevious()));
+
+        $previous = $exception->getPrevious();
+
+        if ($previous instanceof \Exception) {
+            $e->setPrevious(static::create($previous));
+        } elseif ($previous instanceof \Throwable) {
+            $e->setPrevious(static::create(new FatalThrowableError($previous)));
         }
 
         return $e;
@@ -103,13 +70,13 @@ class FlattenException extends LegacyFlattenException
 
     public function toArray()
     {
-        $exceptions = array();
-        foreach (array_merge(array($this), $this->getAllPrevious()) as $exception) {
-            $exceptions[] = array(
+        $exceptions = [];
+        foreach (array_merge([$this], $this->getAllPrevious()) as $exception) {
+            $exceptions[] = [
                 'message' => $exception->getMessage(),
                 'class' => $exception->getClass(),
                 'trace' => $exception->getTrace(),
-            );
+            ];
         }
 
         return $exceptions;
@@ -190,14 +157,14 @@ class FlattenException extends LegacyFlattenException
         return $this->previous;
     }
 
-    public function setPrevious(FlattenException $previous)
+    public function setPrevious(self $previous)
     {
         $this->previous = $previous;
     }
 
     public function getAllPrevious()
     {
-        $exceptions = array();
+        $exceptions = [];
         $e = $this;
         while ($e = $e->getPrevious()) {
             $exceptions[] = $e;
@@ -213,42 +180,13 @@ class FlattenException extends LegacyFlattenException
 
     public function setTraceFromException(\Exception $exception)
     {
-        $trace = $exception->getTrace();
-
-        if ($exception instanceof FatalErrorException) {
-            if (function_exists('xdebug_get_function_stack')) {
-                $trace = array_slice(array_reverse(xdebug_get_function_stack()), 4);
-
-                foreach ($trace as $i => $frame) {
-                    //  XDebug pre 2.1.1 doesn't currently set the call type key http://bugs.xdebug.org/view.php?id=695
-                    if (!isset($frame['type'])) {
-                        $trace[$i]['type'] = '??';
-                    }
-
-                    if ('dynamic' === $trace[$i]['type']) {
-                        $trace[$i]['type'] = '->';
-                    } elseif ('static' === $trace[$i]['type']) {
-                        $trace[$i]['type'] = '::';
-                    }
-
-                    // XDebug also has a different name for the parameters array
-                    if (isset($frame['params']) && !isset($frame['args'])) {
-                        $trace[$i]['args'] = $frame['params'];
-                        unset($trace[$i]['params']);
-                    }
-                }
-            } else {
-                $trace = array_slice(array_reverse($trace), 1);
-            }
-        }
-
-        $this->setTrace($trace, $exception->getFile(), $exception->getLine());
+        $this->setTrace($exception->getTrace(), $exception->getFile(), $exception->getLine());
     }
 
     public function setTrace($trace, $file, $line)
     {
-        $this->trace = array();
-        $this->trace[] = array(
+        $this->trace = [];
+        $this->trace[] = [
             'namespace' => '',
             'short_class' => '',
             'class' => '',
@@ -256,8 +194,8 @@ class FlattenException extends LegacyFlattenException
             'function' => '',
             'file' => $file,
             'line' => $line,
-            'args' => array(),
-        );
+            'args' => [],
+        ];
         foreach ($trace as $entry) {
             $class = '';
             $namespace = '';
@@ -267,7 +205,7 @@ class FlattenException extends LegacyFlattenException
                 $namespace = implode('\\', $parts);
             }
 
-            $this->trace[] = array(
+            $this->trace[] = [
                 'namespace' => $namespace,
                 'short_class' => $class,
                 'class' => isset($entry['class']) ? $entry['class'] : '',
@@ -275,37 +213,41 @@ class FlattenException extends LegacyFlattenException
                 'function' => isset($entry['function']) ? $entry['function'] : null,
                 'file' => isset($entry['file']) ? $entry['file'] : null,
                 'line' => isset($entry['line']) ? $entry['line'] : null,
-                'args' => isset($entry['args']) ? $this->flattenArgs($entry['args']) : array(),
-            );
+                'args' => isset($entry['args']) ? $this->flattenArgs($entry['args']) : [],
+            ];
         }
     }
 
     private function flattenArgs($args, $level = 0, &$count = 0)
     {
-        $result = array();
+        $result = [];
         foreach ($args as $key => $value) {
             if (++$count > 1e4) {
-                return array('array', '*SKIPPED over 10000 entries*');
+                return ['array', '*SKIPPED over 10000 entries*'];
             }
-            if (is_object($value)) {
-                $result[$key] = array('object', get_class($value));
-            } elseif (is_array($value)) {
+            if ($value instanceof \__PHP_Incomplete_Class) {
+                // is_object() returns false on PHP<=7.1
+                $result[$key] = ['incomplete-object', $this->getClassNameFromIncomplete($value)];
+            } elseif (\is_object($value)) {
+                $result[$key] = ['object', \get_class($value)];
+            } elseif (\is_array($value)) {
                 if ($level > 10) {
-                    $result[$key] = array('array', '*DEEP NESTED ARRAY*');
+                    $result[$key] = ['array', '*DEEP NESTED ARRAY*'];
                 } else {
-                    $result[$key] = array('array', $this->flattenArgs($value, $level + 1, $count));
+                    $result[$key] = ['array', $this->flattenArgs($value, $level + 1, $count)];
                 }
             } elseif (null === $value) {
-                $result[$key] = array('null', null);
-            } elseif (is_bool($value)) {
-                $result[$key] = array('boolean', $value);
-            } elseif (is_resource($value)) {
-                $result[$key] = array('resource', get_resource_type($value));
-            } elseif ($value instanceof \__PHP_Incomplete_Class) {
-                // Special case of object, is_object will return false
-                $result[$key] = array('incomplete-object', $this->getClassNameFromIncomplete($value));
+                $result[$key] = ['null', null];
+            } elseif (\is_bool($value)) {
+                $result[$key] = ['boolean', $value];
+            } elseif (\is_int($value)) {
+                $result[$key] = ['integer', $value];
+            } elseif (\is_float($value)) {
+                $result[$key] = ['float', $value];
+            } elseif (\is_resource($value)) {
+                $result[$key] = ['resource', get_resource_type($value)];
             } else {
-                $result[$key] = array('string', (string) $value);
+                $result[$key] = ['string', (string) $value];
             }
         }
 

Exception/OutOfMemoryException.php

@@ -12,10 +12,10 @@
 namespace Symfony\Component\Debug\Exception;
 
 /**
- * Used to stop execution of a PHP script after handling a fatal error.
+ * Out of memory exception.
  *
- * @author Fabien Potencier <fabien@symfony.com>
+ * @author Nicolas Grekas <p@tchwork.com>
  */
-class DummyException extends \ErrorException
+class OutOfMemoryException extends FatalErrorException
 {
 }

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 = [], $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 [
+            'severity' => $this->severity,
+            'file' => $this->file,
+            'line' => $this->line,
+            'trace' => $this->trace,
+            'count' => $this->count,
+        ];
+    }
+}

Exception/UndefinedFunctionException.php

@@ -0,0 +1,36 @@
+<?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;
+
+/**
+ * Undefined Function Exception.
+ *
+ * @author Konstanton Myakshin <koc-dp@yandex.ru>
+ */
+class UndefinedFunctionException extends FatalErrorException
+{
+    public function __construct($message, \ErrorException $previous)
+    {
+        parent::__construct(
+            $message,
+            $previous->getCode(),
+            $previous->getSeverity(),
+            $previous->getFile(),
+            $previous->getLine(),
+            null,
+            true,
+            null,
+            $previous->getPrevious()
+        );
+        $this->setTrace($previous->getTrace());
+    }
+}

Exception/UndefinedMethodException.php

@@ -0,0 +1,36 @@
+<?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;
+
+/**
+ * Undefined Method Exception.
+ *
+ * @author Grégoire Pineau <lyrixx@lyrixx.info>
+ */
+class UndefinedMethodException extends FatalErrorException
+{
+    public function __construct($message, \ErrorException $previous)
+    {
+        parent::__construct(
+            $message,
+            $previous->getCode(),
+            $previous->getSeverity(),
+            $previous->getFile(),
+            $previous->getLine(),
+            null,
+            true,
+            null,
+            $previous->getPrevious()
+        );
+        $this->setTrace($previous->getTrace());
+    }
+}

FatalErrorHandler/ClassNotFoundFatalErrorHandler.php

@@ -0,0 +1,214 @@
+<?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\FatalErrorHandler;
+
+use Composer\Autoload\ClassLoader as ComposerClassLoader;
+use Symfony\Component\ClassLoader\ClassLoader as SymfonyClassLoader;
+use Symfony\Component\Debug\DebugClassLoader;
+use Symfony\Component\Debug\Exception\ClassNotFoundException;
+use Symfony\Component\Debug\Exception\FatalErrorException;
+
+/**
+ * ErrorHandler for classes that do not exist.
+ *
+ * @author Fabien Potencier <fabien@symfony.com>
+ */
+class ClassNotFoundFatalErrorHandler implements FatalErrorHandlerInterface
+{
+    /**
+     * {@inheritdoc}
+     */
+    public function handleError(array $error, FatalErrorException $exception)
+    {
+        $messageLen = \strlen($error['message']);
+        $notFoundSuffix = '\' not found';
+        $notFoundSuffixLen = \strlen($notFoundSuffix);
+        if ($notFoundSuffixLen > $messageLen) {
+            return null;
+        }
+
+        if (0 !== substr_compare($error['message'], $notFoundSuffix, -$notFoundSuffixLen)) {
+            return null;
+        }
+
+        foreach (['class', 'interface', 'trait'] as $typeName) {
+            $prefix = ucfirst($typeName).' \'';
+            $prefixLen = \strlen($prefix);
+            if (0 !== strpos($error['message'], $prefix)) {
+                continue;
+            }
+
+            $fullyQualifiedClassName = substr($error['message'], $prefixLen, -$notFoundSuffixLen);
+            if (false !== $namespaceSeparatorIndex = strrpos($fullyQualifiedClassName, '\\')) {
+                $className = substr($fullyQualifiedClassName, $namespaceSeparatorIndex + 1);
+                $namespacePrefix = substr($fullyQualifiedClassName, 0, $namespaceSeparatorIndex);
+                $message = sprintf('Attempted to load %s "%s" from namespace "%s".', $typeName, $className, $namespacePrefix);
+                $tail = ' for another namespace?';
+            } else {
+                $className = $fullyQualifiedClassName;
+                $message = sprintf('Attempted to load %s "%s" from the global namespace.', $typeName, $className);
+                $tail = '?';
+            }
+
+            if ($candidates = $this->getClassCandidates($className)) {
+                $tail = array_pop($candidates).'"?';
+                if ($candidates) {
+                    $tail = ' for e.g. "'.implode('", "', $candidates).'" or "'.$tail;
+                } else {
+                    $tail = ' for "'.$tail;
+                }
+            }
+            $message .= "\nDid you forget a \"use\" statement".$tail;
+
+            return new ClassNotFoundException($message, $exception);
+        }
+
+        return null;
+    }
+
+    /**
+     * Tries to guess the full namespace for a given class name.
+     *
+     * By default, it looks for PSR-0 and PSR-4 classes registered via a Symfony or a Composer
+     * autoloader (that should cover all common cases).
+     *
+     * @param string $class A class name (without its namespace)
+     *
+     * @return array An array of possible fully qualified class names
+     */
+    private function getClassCandidates($class)
+    {
+        if (!\is_array($functions = spl_autoload_functions())) {
+            return [];
+        }
+
+        // find Symfony and Composer autoloaders
+        $classes = [];
+
+        foreach ($functions as $function) {
+            if (!\is_array($function)) {
+                continue;
+            }
+            // get class loaders wrapped by DebugClassLoader
+            if ($function[0] instanceof DebugClassLoader) {
+                $function = $function[0]->getClassLoader();
+
+                if (!\is_array($function)) {
+                    continue;
+                }
+            }
+
+            if ($function[0] instanceof ComposerClassLoader || $function[0] instanceof SymfonyClassLoader) {
+                foreach ($function[0]->getPrefixes() as $prefix => $paths) {
+                    foreach ($paths as $path) {
+                        $classes = array_merge($classes, $this->findClassInPath($path, $class, $prefix));
+                    }
+                }
+            }
+            if ($function[0] instanceof ComposerClassLoader) {
+                foreach ($function[0]->getPrefixesPsr4() as $prefix => $paths) {
+                    foreach ($paths as $path) {
+                        $classes = array_merge($classes, $this->findClassInPath($path, $class, $prefix));
+                    }
+                }
+            }
+        }
+
+        return array_unique($classes);
+    }
+
+    /**
+     * @param string $path
+     * @param string $class
+     * @param string $prefix
+     *
+     * @return array
+     */
+    private function findClassInPath($path, $class, $prefix)
+    {
+        if (!$path = realpath($path.'/'.strtr($prefix, '\\_', '//')) ?: realpath($path.'/'.\dirname(strtr($prefix, '\\_', '//'))) ?: realpath($path)) {
+            return [];
+        }
+
+        $classes = [];
+        $filename = $class.'.php';
+        foreach (new \RecursiveIteratorIterator(new \RecursiveDirectoryIterator($path, \RecursiveDirectoryIterator::SKIP_DOTS), \RecursiveIteratorIterator::LEAVES_ONLY) as $file) {
+            if ($filename == $file->getFileName() && $class = $this->convertFileToClass($path, $file->getPathName(), $prefix)) {
+                $classes[] = $class;
+            }
+        }
+
+        return $classes;
+    }
+
+    /**
+     * @param string $path
+     * @param string $file
+     * @param string $prefix
+     *
+     * @return string|null
+     */
+    private function convertFileToClass($path, $file, $prefix)
+    {
+        $candidates = [
+            // namespaced class
+            $namespacedClass = str_replace([$path.\DIRECTORY_SEPARATOR, '.php', '/'], ['', '', '\\'], $file),
+            // namespaced class (with target dir)
+            $prefix.$namespacedClass,
+            // namespaced class (with target dir and separator)
+            $prefix.'\\'.$namespacedClass,
+            // PEAR class
+            str_replace('\\', '_', $namespacedClass),
+            // PEAR class (with target dir)
+            str_replace('\\', '_', $prefix.$namespacedClass),
+            // PEAR class (with target dir and separator)
+            str_replace('\\', '_', $prefix.'\\'.$namespacedClass),
+        ];
+
+        if ($prefix) {
+            $candidates = array_filter($candidates, function ($candidate) use ($prefix) { return 0 === strpos($candidate, $prefix); });
+        }
+
+        // We cannot use the autoloader here as most of them use require; but if the class
+        // is not found, the new autoloader call will require the file again leading to a
+        // "cannot redeclare class" error.
+        foreach ($candidates as $candidate) {
+            if ($this->classExists($candidate)) {
+                return $candidate;
+            }
+        }
+
+        try {
+            require_once $file;
+        } catch (\Throwable $e) {
+            return null;
+        }
+
+        foreach ($candidates as $candidate) {
+            if ($this->classExists($candidate)) {
+                return $candidate;
+            }
+        }
+
+        return null;
+    }
+
+    /**
+     * @param string $class
+     *
+     * @return bool
+     */
+    private function classExists($class)
+    {
+        return class_exists($class, false) || interface_exists($class, false) || trait_exists($class, false);
+    }
+}

FatalErrorHandler/FatalErrorHandlerInterface.php

@@ -0,0 +1,32 @@
+<?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\FatalErrorHandler;
+
+use Symfony\Component\Debug\Exception\FatalErrorException;
+
+/**
+ * Attempts to convert fatal errors to exceptions.
+ *
+ * @author Fabien Potencier <fabien@symfony.com>
+ */
+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
+     *
+     * @return FatalErrorException|null A FatalErrorException instance if the class is able to convert the error, null otherwise
+     */
+    public function handleError(array $error, FatalErrorException $exception);
+}

FatalErrorHandler/UndefinedFunctionFatalErrorHandler.php

@@ -0,0 +1,84 @@
+<?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\FatalErrorHandler;
+
+use Symfony\Component\Debug\Exception\FatalErrorException;
+use Symfony\Component\Debug\Exception\UndefinedFunctionException;
+
+/**
+ * ErrorHandler for undefined functions.
+ *
+ * @author Fabien Potencier <fabien@symfony.com>
+ */
+class UndefinedFunctionFatalErrorHandler implements FatalErrorHandlerInterface
+{
+    /**
+     * {@inheritdoc}
+     */
+    public function handleError(array $error, FatalErrorException $exception)
+    {
+        $messageLen = \strlen($error['message']);
+        $notFoundSuffix = '()';
+        $notFoundSuffixLen = \strlen($notFoundSuffix);
+        if ($notFoundSuffixLen > $messageLen) {
+            return null;
+        }
+
+        if (0 !== substr_compare($error['message'], $notFoundSuffix, -$notFoundSuffixLen)) {
+            return null;
+        }
+
+        $prefix = 'Call to undefined function ';
+        $prefixLen = \strlen($prefix);
+        if (0 !== strpos($error['message'], $prefix)) {
+            return null;
+        }
+
+        $fullyQualifiedFunctionName = substr($error['message'], $prefixLen, -$notFoundSuffixLen);
+        if (false !== $namespaceSeparatorIndex = strrpos($fullyQualifiedFunctionName, '\\')) {
+            $functionName = substr($fullyQualifiedFunctionName, $namespaceSeparatorIndex + 1);
+            $namespacePrefix = substr($fullyQualifiedFunctionName, 0, $namespaceSeparatorIndex);
+            $message = sprintf('Attempted to call function "%s" from namespace "%s".', $functionName, $namespacePrefix);
+        } else {
+            $functionName = $fullyQualifiedFunctionName;
+            $message = sprintf('Attempted to call function "%s" from the global namespace.', $functionName);
+        }
+
+        $candidates = [];
+        foreach (get_defined_functions() as $type => $definedFunctionNames) {
+            foreach ($definedFunctionNames as $definedFunctionName) {
+                if (false !== $namespaceSeparatorIndex = strrpos($definedFunctionName, '\\')) {
+                    $definedFunctionNameBasename = substr($definedFunctionName, $namespaceSeparatorIndex + 1);
+                } else {
+                    $definedFunctionNameBasename = $definedFunctionName;
+                }
+
+                if ($definedFunctionNameBasename === $functionName) {
+                    $candidates[] = '\\'.$definedFunctionName;
+                }
+            }
+        }
+
+        if ($candidates) {
+            sort($candidates);
+            $last = array_pop($candidates).'"?';
+            if ($candidates) {
+                $candidates = 'e.g. "'.implode('", "', $candidates).'" or "'.$last;
+            } else {
+                $candidates = '"'.$last;
+            }
+            $message .= "\nDid you mean to call ".$candidates;
+        }
+
+        return new UndefinedFunctionException($message, $exception);
+    }
+}

FatalErrorHandler/UndefinedMethodFatalErrorHandler.php

@@ -0,0 +1,66 @@
+<?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\FatalErrorHandler;
+
+use Symfony\Component\Debug\Exception\FatalErrorException;
+use Symfony\Component\Debug\Exception\UndefinedMethodException;
+
+/**
+ * ErrorHandler for undefined methods.
+ *
+ * @author Grégoire Pineau <lyrixx@lyrixx.info>
+ */
+class UndefinedMethodFatalErrorHandler implements FatalErrorHandlerInterface
+{
+    /**
+     * {@inheritdoc}
+     */
+    public function handleError(array $error, FatalErrorException $exception)
+    {
+        preg_match('/^Call to undefined method (.*)::(.*)\(\)$/', $error['message'], $matches);
+        if (!$matches) {
+            return null;
+        }
+
+        $className = $matches[1];
+        $methodName = $matches[2];
+
+        $message = sprintf('Attempted to call an undefined method named "%s" of class "%s".', $methodName, $className);
+
+        if (!class_exists($className) || null === $methods = get_class_methods($className)) {
+            // failed to get the class or its methods on which an unknown method was called (for example on an anonymous class)
+            return new UndefinedMethodException($message, $exception);
+        }
+
+        $candidates = [];
+        foreach ($methods as $definedMethodName) {
+            $lev = levenshtein($methodName, $definedMethodName);
+            if ($lev <= \strlen($methodName) / 3 || false !== strpos($definedMethodName, $methodName)) {
+                $candidates[] = $definedMethodName;
+            }
+        }
+
+        if ($candidates) {
+            sort($candidates);
+            $last = array_pop($candidates).'"?';
+            if ($candidates) {
+                $candidates = 'e.g. "'.implode('", "', $candidates).'" or "'.$last;
+            } else {
+                $candidates = '"'.$last;
+            }
+
+            $message .= "\nDid you mean to call ".$candidates;
+        }
+
+        return new UndefinedMethodException($message, $exception);
+    }
+}

LICENSE

@@ -1,4 +1,4 @@
-Copyright (c) 2004-2015 Fabien Potencier
+Copyright (c) 2004-2020 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

README.md

@@ -1,44 +1,13 @@
 Debug Component
 ===============
 
-Debug provides tools to make debugging easier.
-
-Enabling all debug tools is as easy as calling the `enable()` method on the
-main `Debug` class:
-
-```php
-use Symfony\Component\Debug\Debug;
-
-Debug::enable();
-```
-
-You can also use the tools individually:
-
-```php
-use Symfony\Component\Debug\ErrorHandler;
-use Symfony\Component\Debug\ExceptionHandler;
-
-error_reporting(-1);
-
-ErrorHandler::register($errorReportingLevel);
-if ('cli' !== php_sapi_name()) {
-    ExceptionHandler::register();
-} elseif (!ini_get('log_errors') || ini_get('error_log')) {
-    ini_set('display_errors', 1);
-}
-```
-
-Note that the `Debug::enable()` call also registers the debug class loader
-from the Symfony ClassLoader component when available.
-
-This component can optionally take advantage of the features of the HttpKernel
-and HttpFoundation components.
+The Debug component provides tools to ease debugging PHP code.
 
 Resources
 ---------
 
-You can run the unit tests with the following command:
-
-    $ cd path/to/Symfony/Component/Debug/
-    $ composer install
-    $ phpunit
+  * [Documentation](https://symfony.com/doc/current/components/debug.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)
+    in the [main Symfony repository](https://github.com/symfony/symfony)

Resources/ext/README.md

@@ -0,0 +1,134 @@
+Symfony Debug Extension for PHP 5
+=================================
+
+This extension publishes several functions to help building powerful debugging tools.
+It is compatible with PHP 5.3, 5.4, 5.5 and 5.6; with ZTS and non-ZTS modes.
+It is not required thus not provided for PHP 7.
+
+symfony_zval_info()
+-------------------
+
+- exposes zval_hash/refcounts, allowing e.g. efficient exploration of arbitrary structures in PHP,
+- does work with references, preventing memory copying.
+
+Its behavior is about the same as:
+
+```php
+<?php
+
+function symfony_zval_info($key, $array, $options = 0)
+{
+
+    // $options is currently not used, but could be in future version.
+
+    if (!array_key_exists($key, $array)) {
+        return null;
+    }
+
+    $info = [
+        'type' => gettype($array[$key]),
+        'zval_hash' => /* hashed memory address of $array[$key] */,
+        'zval_refcount' => /* internal zval refcount of $array[$key] */,
+        'zval_isref' => /* is_ref status of $array[$key] */,
+    ];
+
+    switch ($info['type']) {
+        case 'object':
+            $info += [
+                'object_class' => get_class($array[$key]),
+                'object_refcount' => /* internal object refcount of $array[$key] */,
+                'object_hash' => spl_object_hash($array[$key]),
+                'object_handle' => /* internal object handle $array[$key] */,
+            ];
+            break;
+
+        case 'resource':
+            $info += [
+                'resource_handle' => (int) $array[$key],
+                'resource_type' => get_resource_type($array[$key]),
+                'resource_refcount' => /* internal resource refcount of $array[$key] */,
+            ];
+            break;
+
+        case 'array':
+            $info += [
+                'array_count' => count($array[$key]),
+            ];
+            break;
+
+        case 'string':
+            $info += [
+                'strlen' => strlen($array[$key]),
+            ];
+            break;
+    }
+
+    return $info;
+}
+```
+
+symfony_debug_backtrace()
+-------------------------
+
+This function works like debug_backtrace(), except that it can fetch the full backtrace in case of fatal errors:
+
+```php
+function foo() { fatal(); }
+function bar() { foo(); }
+
+function sd() { var_dump(symfony_debug_backtrace()); }
+
+register_shutdown_function('sd');
+
+bar();
+
+/* Will output
+Fatal error: Call to undefined function fatal() in foo.php on line 42
+array(3) {
+  [0]=>
+  array(2) {
+    ["function"]=>
+    string(2) "sd"
+    ["args"]=>
+    array(0) {
+    }
+  }
+  [1]=>
+  array(4) {
+    ["file"]=>
+    string(7) "foo.php"
+    ["line"]=>
+    int(1)
+    ["function"]=>
+    string(3) "foo"
+    ["args"]=>
+    array(0) {
+    }
+  }
+  [2]=>
+  array(4) {
+    ["file"]=>
+    string(102) "foo.php"
+    ["line"]=>
+    int(2)
+    ["function"]=>
+    string(3) "bar"
+    ["args"]=>
+    array(0) {
+    }
+  }
+}
+*/
+```
+
+Usage
+-----
+
+To enable the extension from source, run:
+
+```
+    phpize
+    ./configure
+    make
+    sudo make install
+```

Resources/ext/config.m4

@@ -0,0 +1,63 @@
+dnl $Id$
+dnl config.m4 for extension symfony_debug
+
+dnl Comments in this file start with the string 'dnl'.
+dnl Remove where necessary. This file will not work
+dnl without editing.
+
+dnl If your extension references something external, use with:
+
+dnl PHP_ARG_WITH(symfony_debug, for symfony_debug support,
+dnl Make sure that the comment is aligned:
+dnl [  --with-symfony_debug             Include symfony_debug support])
+
+dnl Otherwise use enable:
+
+PHP_ARG_ENABLE(symfony_debug, whether to enable symfony_debug support,
+dnl Make sure that the comment is aligned:
+[  --enable-symfony_debug           Enable symfony_debug support])
+
+if test "$PHP_SYMFONY_DEBUG" != "no"; then
+  dnl Write more examples of tests here...
+
+  dnl # --with-symfony_debug -> check with-path
+  dnl SEARCH_PATH="/usr/local /usr"     # you might want to change this
+  dnl SEARCH_FOR="/include/symfony_debug.h"  # you most likely want to change this
+  dnl if test -r $PHP_SYMFONY_DEBUG/$SEARCH_FOR; then # path given as parameter
+  dnl   SYMFONY_DEBUG_DIR=$PHP_SYMFONY_DEBUG
+  dnl else # search default path list
+  dnl   AC_MSG_CHECKING([for symfony_debug files in default path])
+  dnl   for i in $SEARCH_PATH ; do
+  dnl     if test -r $i/$SEARCH_FOR; then
+  dnl       SYMFONY_DEBUG_DIR=$i
+  dnl       AC_MSG_RESULT(found in $i)
+  dnl     fi
+  dnl   done
+  dnl fi
+  dnl
+  dnl if test -z "$SYMFONY_DEBUG_DIR"; then
+  dnl   AC_MSG_RESULT([not found])
+  dnl   AC_MSG_ERROR([Please reinstall the symfony_debug distribution])
+  dnl fi
+
+  dnl # --with-symfony_debug -> add include path
+  dnl PHP_ADD_INCLUDE($SYMFONY_DEBUG_DIR/include)
+
+  dnl # --with-symfony_debug -> check for lib and symbol presence
+  dnl LIBNAME=symfony_debug # you may want to change this
+  dnl LIBSYMBOL=symfony_debug # you most likely want to change this 
+
+  dnl PHP_CHECK_LIBRARY($LIBNAME,$LIBSYMBOL,
+  dnl [
+  dnl   PHP_ADD_LIBRARY_WITH_PATH($LIBNAME, $SYMFONY_DEBUG_DIR/lib, SYMFONY_DEBUG_SHARED_LIBADD)
+  dnl   AC_DEFINE(HAVE_SYMFONY_DEBUGLIB,1,[ ])
+  dnl ],[
+  dnl   AC_MSG_ERROR([wrong symfony_debug lib version or lib not found])
+  dnl ],[
+  dnl   -L$SYMFONY_DEBUG_DIR/lib -lm
+  dnl ])
+  dnl
+  dnl PHP_SUBST(SYMFONY_DEBUG_SHARED_LIBADD)
+
+  PHP_NEW_EXTENSION(symfony_debug, symfony_debug.c, $ext_shared)
+fi

Resources/ext/config.w32

@@ -0,0 +1,13 @@
+// $Id$
+// vim:ft=javascript
+
+// If your extension references something external, use ARG_WITH
+// ARG_WITH("symfony_debug", "for symfony_debug support", "no");
+
+// Otherwise, use ARG_ENABLE
+// ARG_ENABLE("symfony_debug", "enable symfony_debug support", "no");
+
+if (PHP_SYMFONY_DEBUG != "no") {
+	EXTENSION("symfony_debug", "symfony_debug.c");
+}
+

Resources/ext/php_symfony_debug.h

@@ -0,0 +1,60 @@
+/*
+ * 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.
+ */
+
+#ifndef PHP_SYMFONY_DEBUG_H
+#define PHP_SYMFONY_DEBUG_H
+
+extern zend_module_entry symfony_debug_module_entry;
+#define phpext_symfony_debug_ptr &symfony_debug_module_entry
+
+#define PHP_SYMFONY_DEBUG_VERSION "2.7"
+
+#ifdef PHP_WIN32
+#	define PHP_SYMFONY_DEBUG_API __declspec(dllexport)
+#elif defined(__GNUC__) && __GNUC__ >= 4
+#	define PHP_SYMFONY_DEBUG_API __attribute__ ((visibility("default")))
+#else
+#	define PHP_SYMFONY_DEBUG_API
+#endif
+
+#ifdef ZTS
+#include "TSRM.h"
+#endif
+
+ZEND_BEGIN_MODULE_GLOBALS(symfony_debug)
+	intptr_t req_rand_init;
+	void (*old_error_cb)(int type, const char *error_filename, const uint error_lineno, const char *format, va_list args);
+	zval *debug_bt;
+ZEND_END_MODULE_GLOBALS(symfony_debug)
+
+PHP_MINIT_FUNCTION(symfony_debug);
+PHP_MSHUTDOWN_FUNCTION(symfony_debug);
+PHP_RINIT_FUNCTION(symfony_debug);
+PHP_RSHUTDOWN_FUNCTION(symfony_debug);
+PHP_MINFO_FUNCTION(symfony_debug);
+PHP_GINIT_FUNCTION(symfony_debug);
+PHP_GSHUTDOWN_FUNCTION(symfony_debug);
+
+PHP_FUNCTION(symfony_zval_info);
+PHP_FUNCTION(symfony_debug_backtrace);
+
+static char *_symfony_debug_memory_address_hash(void * TSRMLS_DC);
+static const char *_symfony_debug_zval_type(zval *);
+static const char* _symfony_debug_get_resource_type(long TSRMLS_DC);
+static int _symfony_debug_get_resource_refcount(long TSRMLS_DC);
+
+void symfony_debug_error_cb(int type, const char *error_filename, const uint error_lineno, const char *format, va_list args);
+
+#ifdef ZTS
+#define SYMFONY_DEBUG_G(v) TSRMG(symfony_debug_globals_id, zend_symfony_debug_globals *, v)
+#else
+#define SYMFONY_DEBUG_G(v) (symfony_debug_globals.v)
+#endif
+
+#endif	/* PHP_SYMFONY_DEBUG_H */

Resources/ext/symfony_debug.c

@@ -0,0 +1,283 @@
+/*
+ * 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.
+ */
+
+#ifdef HAVE_CONFIG_H
+#include "config.h"
+#endif
+
+#include "php.h"
+#ifdef ZTS
+#include "TSRM.h"
+#endif
+#include "php_ini.h"
+#include "ext/standard/info.h"
+#include "php_symfony_debug.h"
+#include "ext/standard/php_rand.h"
+#include "ext/standard/php_lcg.h"
+#include "ext/spl/php_spl.h"
+#include "Zend/zend_gc.h"
+#include "Zend/zend_builtin_functions.h"
+#include "Zend/zend_extensions.h" /* for ZEND_EXTENSION_API_NO */
+#include "ext/standard/php_array.h"
+#include "Zend/zend_interfaces.h"
+#include "SAPI.h"
+
+#define IS_PHP_53 ZEND_EXTENSION_API_NO == 220090626
+
+ZEND_DECLARE_MODULE_GLOBALS(symfony_debug)
+
+ZEND_BEGIN_ARG_INFO_EX(symfony_zval_arginfo, 0, 0, 2)
+	ZEND_ARG_INFO(0, key)
+	ZEND_ARG_ARRAY_INFO(0, array, 0)
+	ZEND_ARG_INFO(0, options)
+ZEND_END_ARG_INFO()
+
+const zend_function_entry symfony_debug_functions[] = {
+	PHP_FE(symfony_zval_info,	symfony_zval_arginfo)
+	PHP_FE(symfony_debug_backtrace, NULL)
+	PHP_FE_END
+};
+
+PHP_FUNCTION(symfony_debug_backtrace)
+{
+	if (zend_parse_parameters_none() == FAILURE) {
+		return;
+	}
+#if IS_PHP_53
+	zend_fetch_debug_backtrace(return_value, 1, 0 TSRMLS_CC);
+#else
+	zend_fetch_debug_backtrace(return_value, 1, 0, 0 TSRMLS_CC);
+#endif
+
+	if (!SYMFONY_DEBUG_G(debug_bt)) {
+		return;
+	}
+
+	php_array_merge(Z_ARRVAL_P(return_value), Z_ARRVAL_P(SYMFONY_DEBUG_G(debug_bt)), 0 TSRMLS_CC);
+}
+
+PHP_FUNCTION(symfony_zval_info)
+{
+	zval *key = NULL, *arg = NULL;
+	zval **data = NULL;
+	HashTable *array = NULL;
+	long options = 0;
+
+	if (zend_parse_parameters(ZEND_NUM_ARGS() TSRMLS_CC, "zh|l", &key, &array, &options) == FAILURE) {
+		return;
+	}
+
+	switch (Z_TYPE_P(key)) {
+		case IS_STRING:
+			if (zend_symtable_find(array, Z_STRVAL_P(key), Z_STRLEN_P(key) + 1, (void **)&data) == FAILURE) {
+				return;
+			}
+		break;
+		case IS_LONG:
+			if (zend_hash_index_find(array, Z_LVAL_P(key), (void **)&data)) {
+				return;
+			}
+		break;
+	}
+
+	arg = *data;
+
+	array_init(return_value);
+
+	add_assoc_string(return_value, "type", (char *)_symfony_debug_zval_type(arg), 1);
+	add_assoc_stringl(return_value, "zval_hash", _symfony_debug_memory_address_hash((void *)arg TSRMLS_CC), 16, 0);
+	add_assoc_long(return_value, "zval_refcount", Z_REFCOUNT_P(arg));
+	add_assoc_bool(return_value, "zval_isref", (zend_bool)Z_ISREF_P(arg));
+
+	if (Z_TYPE_P(arg) == IS_OBJECT) {
+		char hash[33] = {0};
+
+		php_spl_object_hash(arg, (char *)hash TSRMLS_CC);
+		add_assoc_stringl(return_value, "object_class", (char *)Z_OBJCE_P(arg)->name, Z_OBJCE_P(arg)->name_length, 1);
+		add_assoc_long(return_value, "object_refcount", EG(objects_store).object_buckets[Z_OBJ_HANDLE_P(arg)].bucket.obj.refcount);
+		add_assoc_string(return_value, "object_hash", hash, 1);
+		add_assoc_long(return_value, "object_handle", Z_OBJ_HANDLE_P(arg));
+	} else if (Z_TYPE_P(arg) == IS_ARRAY) {
+		add_assoc_long(return_value, "array_count", zend_hash_num_elements(Z_ARRVAL_P(arg)));
+	} else if(Z_TYPE_P(arg) == IS_RESOURCE) {
+		add_assoc_long(return_value, "resource_handle", Z_LVAL_P(arg));
+		add_assoc_string(return_value, "resource_type", (char *)_symfony_debug_get_resource_type(Z_LVAL_P(arg) TSRMLS_CC), 1);
+		add_assoc_long(return_value, "resource_refcount", _symfony_debug_get_resource_refcount(Z_LVAL_P(arg) TSRMLS_CC));
+	} else if (Z_TYPE_P(arg) == IS_STRING) {
+		add_assoc_long(return_value, "strlen", Z_STRLEN_P(arg));
+	}
+}
+
+void symfony_debug_error_cb(int type, const char *error_filename, const uint error_lineno, const char *format, va_list args)
+{
+	TSRMLS_FETCH();
+	zval *retval;
+
+	switch (type) {
+		case E_ERROR:
+		case E_PARSE:
+		case E_CORE_ERROR:
+		case E_CORE_WARNING:
+		case E_COMPILE_ERROR:
+		case E_COMPILE_WARNING:
+			ALLOC_INIT_ZVAL(retval);
+#if IS_PHP_53
+			zend_fetch_debug_backtrace(retval, 1, 0 TSRMLS_CC);
+#else
+			zend_fetch_debug_backtrace(retval, 1, 0, 0 TSRMLS_CC);
+#endif
+			SYMFONY_DEBUG_G(debug_bt) = retval;
+	}
+
+	SYMFONY_DEBUG_G(old_error_cb)(type, error_filename, error_lineno, format, args);
+}
+
+static const char* _symfony_debug_get_resource_type(long rsid TSRMLS_DC)
+{
+	const char *res_type;
+	res_type = zend_rsrc_list_get_rsrc_type(rsid TSRMLS_CC);
+
+	if (!res_type) {
+		return "Unknown";
+	}
+
+	return res_type;
+}
+
+static int _symfony_debug_get_resource_refcount(long rsid TSRMLS_DC)
+{
+	zend_rsrc_list_entry *le;
+
+	if (zend_hash_index_find(&EG(regular_list), rsid, (void **) &le)==SUCCESS) {
+		return le->refcount;
+	}
+
+	return 0;
+}
+
+static char *_symfony_debug_memory_address_hash(void *address TSRMLS_DC)
+{
+	char *result = NULL;
+	intptr_t address_rand;
+
+	if (!SYMFONY_DEBUG_G(req_rand_init)) {
+		if (!BG(mt_rand_is_seeded)) {
+			php_mt_srand(GENERATE_SEED() TSRMLS_CC);
+		}
+		SYMFONY_DEBUG_G(req_rand_init) = (intptr_t)php_mt_rand(TSRMLS_C);
+	}
+
+	address_rand = (intptr_t)address ^ SYMFONY_DEBUG_G(req_rand_init);
+
+	spprintf(&result, 17, "%016zx", address_rand);
+
+	return result;
+}
+
+static const char *_symfony_debug_zval_type(zval *zv)
+{
+	switch (Z_TYPE_P(zv)) {
+		case IS_NULL:
+			return "NULL";
+			break;
+
+		case IS_BOOL:
+			return "boolean";
+			break;
+
+		case IS_LONG:
+			return "integer";
+			break;
+
+		case IS_DOUBLE:
+			return "double";
+			break;
+
+		case IS_STRING:
+			return "string";
+			break;
+
+		case IS_ARRAY:
+			return "array";
+			break;
+
+		case IS_OBJECT:
+			return "object";
+
+		case IS_RESOURCE:
+			return "resource";
+
+		default:
+			return "unknown type";
+	}
+}
+
+zend_module_entry symfony_debug_module_entry = {
+	STANDARD_MODULE_HEADER,
+	"symfony_debug",
+	symfony_debug_functions,
+	PHP_MINIT(symfony_debug),
+	PHP_MSHUTDOWN(symfony_debug),
+	PHP_RINIT(symfony_debug),
+	PHP_RSHUTDOWN(symfony_debug),
+	PHP_MINFO(symfony_debug),
+	PHP_SYMFONY_DEBUG_VERSION,
+	PHP_MODULE_GLOBALS(symfony_debug),
+	PHP_GINIT(symfony_debug),
+	PHP_GSHUTDOWN(symfony_debug),
+	NULL,
+	STANDARD_MODULE_PROPERTIES_EX
+};
+
+#ifdef COMPILE_DL_SYMFONY_DEBUG
+ZEND_GET_MODULE(symfony_debug)
+#endif
+
+PHP_GINIT_FUNCTION(symfony_debug)
+{
+	memset(symfony_debug_globals, 0 , sizeof(*symfony_debug_globals));
+}
+
+PHP_GSHUTDOWN_FUNCTION(symfony_debug)
+{
+
+}
+
+PHP_MINIT_FUNCTION(symfony_debug)
+{
+	SYMFONY_DEBUG_G(old_error_cb) = zend_error_cb;
+	zend_error_cb                 = symfony_debug_error_cb;
+
+	return SUCCESS;
+}
+
+PHP_MSHUTDOWN_FUNCTION(symfony_debug)
+{
+	zend_error_cb = SYMFONY_DEBUG_G(old_error_cb);
+
+	return SUCCESS;
+}
+
+PHP_RINIT_FUNCTION(symfony_debug)
+{
+	return SUCCESS;
+}
+
+PHP_RSHUTDOWN_FUNCTION(symfony_debug)
+{
+	return SUCCESS;
+}
+
+PHP_MINFO_FUNCTION(symfony_debug)
+{
+	php_info_print_table_start();
+	php_info_print_table_header(2, "Symfony Debug support", "enabled");
+	php_info_print_table_header(2, "Symfony Debug version", PHP_SYMFONY_DEBUG_VERSION);
+	php_info_print_table_end();
+}

Resources/ext/tests/001.phpt

@@ -0,0 +1,155 @@
+--TEST--
+Test symfony_zval_info API
+--SKIPIF--
+<?php if (!extension_loaded('symfony_debug')) {
+    echo 'skip';
+} ?>
+--FILE--
+<?php
+
+$int = 42;
+$float = 42.42;
+$str = 'foobar';
+$object = new StdClass();
+$array = ['foo', 'bar'];
+$resource = tmpfile();
+$null = null;
+$bool = true;
+
+$anotherint = 42;
+$refcount2 = &$anotherint;
+
+$var = [
+    'int' => $int,
+    'float' => $float,
+    'str' => $str,
+    'object' => $object,
+    'array' => $array,
+    'resource' => $resource,
+    'null' => $null,
+    'bool' => $bool,
+    'refcount' => &$refcount2,
+];
+
+var_dump(symfony_zval_info('int', $var));
+var_dump(symfony_zval_info('float', $var));
+var_dump(symfony_zval_info('str', $var));
+var_dump(symfony_zval_info('object', $var));
+var_dump(symfony_zval_info('array', $var));
+var_dump(symfony_zval_info('resource', $var));
+var_dump(symfony_zval_info('null', $var));
+var_dump(symfony_zval_info('bool', $var));
+
+var_dump(symfony_zval_info('refcount', $var));
+var_dump(symfony_zval_info('not-exist', $var));
+?>
+--EXPECTF--
+array(4) {
+  ["type"]=>
+  string(7) "integer"
+  ["zval_hash"]=>
+  string(16) "%s"
+  ["zval_refcount"]=>
+  int(2)
+  ["zval_isref"]=>
+  bool(false)
+}
+array(4) {
+  ["type"]=>
+  string(6) "double"
+  ["zval_hash"]=>
+  string(16) "%s"
+  ["zval_refcount"]=>
+  int(2)
+  ["zval_isref"]=>
+  bool(false)
+}
+array(5) {
+  ["type"]=>
+  string(6) "string"
+  ["zval_hash"]=>
+  string(16) "%s"
+  ["zval_refcount"]=>
+  int(2)
+  ["zval_isref"]=>
+  bool(false)
+  ["strlen"]=>
+  int(6)
+}
+array(8) {
+  ["type"]=>
+  string(6) "object"
+  ["zval_hash"]=>
+  string(16) "%s"
+  ["zval_refcount"]=>
+  int(2)
+  ["zval_isref"]=>
+  bool(false)
+  ["object_class"]=>
+  string(8) "stdClass"
+  ["object_refcount"]=>
+  int(1)
+  ["object_hash"]=>
+  string(32) "%s"
+  ["object_handle"]=>
+  int(%d)
+}
+array(5) {
+  ["type"]=>
+  string(5) "array"
+  ["zval_hash"]=>
+  string(16) "%s"
+  ["zval_refcount"]=>
+  int(2)
+  ["zval_isref"]=>
+  bool(false)
+  ["array_count"]=>
+  int(2)
+}
+array(7) {
+  ["type"]=>
+  string(8) "resource"
+  ["zval_hash"]=>
+  string(16) "%s"
+  ["zval_refcount"]=>
+  int(2)
+  ["zval_isref"]=>
+  bool(false)
+  ["resource_handle"]=>
+  int(%d)
+  ["resource_type"]=>
+  string(6) "stream"
+  ["resource_refcount"]=>
+  int(1)
+}
+array(4) {
+  ["type"]=>
+  string(4) "NULL"
+  ["zval_hash"]=>
+  string(16) "%s"
+  ["zval_refcount"]=>
+  int(2)
+  ["zval_isref"]=>
+  bool(false)
+}
+array(4) {
+  ["type"]=>
+  string(7) "boolean"
+  ["zval_hash"]=>
+  string(16) "%s"
+  ["zval_refcount"]=>
+  int(2)
+  ["zval_isref"]=>
+  bool(false)
+}
+array(4) {
+  ["type"]=>
+  string(7) "integer"
+  ["zval_hash"]=>
+  string(16) "%s"
+  ["zval_refcount"]=>
+  int(3)
+  ["zval_isref"]=>
+  bool(true)
+}
+NULL

Resources/ext/tests/002.phpt

@@ -0,0 +1,65 @@
+--TEST--
+Test symfony_debug_backtrace in case of fatal error
+--SKIPIF--
+<?php if (!extension_loaded('symfony_debug')) {
+    echo 'skip';
+} ?>
+--FILE--
+<?php
+
+function bar()
+{
+    foo();
+}
+
+function foo()
+{
+    notexist();
+}
+
+function bt()
+{
+    print_r(symfony_debug_backtrace());
+}
+
+register_shutdown_function('bt');
+
+bar();
+
+?>
+--EXPECTF--
+Fatal error: Call to undefined function notexist() in %s on line %d
+Array
+(
+    [0] => Array
+        (
+            [function] => bt
+            [args] => Array
+                (
+                )
+
+        )
+
+    [1] => Array
+        (
+            [file] => %s
+            [line] => %d
+            [function] => foo
+            [args] => Array
+                (
+                )
+
+        )
+
+    [2] => Array
+        (
+            [file] => %s
+            [line] => %d
+            [function] => bar
+            [args] => Array
+                (
+                )
+
+        )
+
+)

Resources/ext/tests/002_1.phpt

@@ -0,0 +1,48 @@
+--TEST--
+Test symfony_debug_backtrace in case of non fatal error
+--SKIPIF--
+<?php if (!extension_loaded('symfony_debug')) {
+    echo 'skip';
+} ?>
+--FILE--
+<?php
+
+function bar()
+{
+    bt();
+}
+
+function bt()
+{
+    print_r(symfony_debug_backtrace());
+}
+
+bar();
+
+?>
+--EXPECTF--
+Array
+(
+    [0] => Array
+        (
+            [file] => %s
+            [line] => %d
+            [function] => bt
+            [args] => Array
+                (
+                )
+
+        )
+
+    [1] => Array
+        (
+            [file] => %s
+            [line] => %d
+            [function] => bar
+            [args] => Array
+                (
+                )
+
+        )
+
+)

Resources/ext/tests/003.phpt

@@ -0,0 +1,87 @@
+--TEST--
+Test ErrorHandler in case of fatal error
+--SKIPIF--
+<?php if (!extension_loaded('symfony_debug')) {
+    echo 'skip';
+} ?>
+--FILE--
+<?php
+
+namespace Psr\Log;
+
+class LogLevel
+{
+    const EMERGENCY = 'emergency';
+    const ALERT = 'alert';
+    const CRITICAL = 'critical';
+    const ERROR = 'error';
+    const WARNING = 'warning';
+    const NOTICE = 'notice';
+    const INFO = 'info';
+    const DEBUG = 'debug';
+}
+
+namespace Symfony\Component\Debug;
+
+$dir = __DIR__.'/../../../';
+require $dir.'ErrorHandler.php';
+require $dir.'Exception/FatalErrorException.php';
+require $dir.'Exception/UndefinedFunctionException.php';
+require $dir.'FatalErrorHandler/FatalErrorHandlerInterface.php';
+require $dir.'FatalErrorHandler/ClassNotFoundFatalErrorHandler.php';
+require $dir.'FatalErrorHandler/UndefinedFunctionFatalErrorHandler.php';
+require $dir.'FatalErrorHandler/UndefinedMethodFatalErrorHandler.php';
+
+function bar()
+{
+    foo();
+}
+
+function foo()
+{
+    notexist();
+}
+
+$handler = ErrorHandler::register();
+$handler->setExceptionHandler('print_r');
+
+if (\function_exists('xdebug_disable')) {
+    xdebug_disable();
+}
+
+bar();
+?>
+--EXPECTF--
+Fatal error: Call to undefined function Symfony\Component\Debug\notexist() in %s on line %d
+Symfony\Component\Debug\Exception\UndefinedFunctionException Object
+(
+    [message:protected] => Attempted to call function "notexist" from namespace "Symfony\Component\Debug".
+    [string:Exception:private] => 
+    [code:protected] => 0
+    [file:protected] => %s
+    [line:protected] => %d
+    [trace:Exception:private] => Array
+        (
+            [0] => Array
+                (
+%A                    [function] => Symfony\Component\Debug\foo
+%A                    [args] => Array
+                        (
+                        )
+
+                )
+
+            [1] => Array
+                (
+%A                    [function] => Symfony\Component\Debug\bar
+%A                    [args] => Array
+                        (
+                        )
+
+                )
+%A
+        )
+
+    [previous:Exception:private] => 
+    [severity:protected] => 1
+)

Tests/DebugClassLoaderTest.php

@@ -0,0 +1,445 @@
+<?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 PHPUnit\Framework\TestCase;
+use Symfony\Component\Debug\DebugClassLoader;
+use Symfony\Component\Debug\ErrorHandler;
+
+class DebugClassLoaderTest extends TestCase
+{
+    /**
+     * @var int Error reporting level before running tests
+     */
+    private $errorReporting;
+
+    private $loader;
+
+    protected function setUp()
+    {
+        $this->errorReporting = error_reporting(E_ALL);
+        $this->loader = new ClassLoader();
+        spl_autoload_register([$this->loader, 'loadClass'], true, true);
+        DebugClassLoader::enable();
+    }
+
+    protected function tearDown()
+    {
+        DebugClassLoader::disable();
+        spl_autoload_unregister([$this->loader, 'loadClass']);
+        error_reporting($this->errorReporting);
+    }
+
+    public function testIdempotence()
+    {
+        DebugClassLoader::enable();
+
+        $functions = spl_autoload_functions();
+        foreach ($functions as $function) {
+            if (\is_array($function) && $function[0] instanceof DebugClassLoader) {
+                $reflClass = new \ReflectionClass($function[0]);
+                $reflProp = $reflClass->getProperty('classLoader');
+                $reflProp->setAccessible(true);
+
+                $this->assertNotInstanceOf('Symfony\Component\Debug\DebugClassLoader', $reflProp->getValue($function[0]));
+
+                return;
+            }
+        }
+
+        $this->fail('DebugClassLoader did not register');
+    }
+
+    public function testThrowingClass()
+    {
+        $this->expectException('Exception');
+        $this->expectExceptionMessage('boo');
+        try {
+            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(Fixtures\Throwing::class);
+    }
+
+    public function testUnsilencing()
+    {
+        if (\PHP_VERSION_ID >= 70000) {
+            $this->markTestSkipped('PHP7 throws exceptions, unsilencing is not required anymore.');
+        }
+        if (\defined('HHVM_VERSION')) {
+            $this->markTestSkipped('HHVM is not handled in this test case.');
+        }
+
+        ob_start();
+
+        $this->iniSet('log_errors', 0);
+        $this->iniSet('display_errors', 1);
+
+        // See below: this will fail with parse error
+        // but this should not be @-silenced.
+        @class_exists(TestingUnsilencing::class, true);
+
+        $output = ob_get_clean();
+
+        $this->assertStringMatchesFormat('%aParse error%a', $output);
+    }
+
+    public function testStacking()
+    {
+        // the ContextErrorException must not be loaded to test the workaround
+        // for https://bugs.php.net/65322.
+        if (class_exists('Symfony\Component\Debug\Exception\ContextErrorException', false)) {
+            $this->markTestSkipped('The ContextErrorException class is already loaded.');
+        }
+        if (\defined('HHVM_VERSION')) {
+            $this->markTestSkipped('HHVM is not handled in this test case.');
+        }
+
+        ErrorHandler::register();
+
+        try {
+            // Trigger autoloading + E_STRICT at compile time
+            // which in turn triggers $errorHandler->handle()
+            // that again triggers autoloading for ContextErrorException.
+            // Error stacking works around the bug above and everything is fine.
+
+            eval('
+                namespace '.__NAMESPACE__.';
+                class ChildTestingStacking extends TestingStacking { function foo($bar) {} }
+            ');
+            $this->fail('ContextErrorException expected');
+        } catch (\ErrorException $exception) {
+            // if an exception is thrown, the test passed
+            $this->assertStringStartsWith(__FILE__, $exception->getFile());
+            if (\PHP_VERSION_ID < 70000) {
+                $this->assertRegExp('/^Runtime Notice: Declaration/', $exception->getMessage());
+                $this->assertEquals(E_STRICT, $exception->getSeverity());
+            } else {
+                $this->assertRegExp('/^Warning: Declaration/', $exception->getMessage());
+                $this->assertEquals(E_WARNING, $exception->getSeverity());
+            }
+        } finally {
+            restore_error_handler();
+            restore_exception_handler();
+        }
+    }
+
+    public function testNameCaseMismatch()
+    {
+        $this->expectException('RuntimeException');
+        $this->expectExceptionMessage('Case mismatch between loaded and declared class names');
+        class_exists(TestingCaseMismatch::class, true);
+    }
+
+    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(Fixtures\CaseMismatch::class, true);
+    }
+
+    public function testPsr4CaseMismatch()
+    {
+        $this->expectException('RuntimeException');
+        $this->expectExceptionMessage('Case mismatch between loaded and declared class names');
+        class_exists(__NAMESPACE__.'\Fixtures\Psr4CaseMismatch', true);
+    }
+
+    public function testNotPsr0()
+    {
+        $this->assertTrue(class_exists(__NAMESPACE__.'\Fixtures\NotPSR0', true));
+    }
+
+    public function testNotPsr0Bis()
+    {
+        $this->assertTrue(class_exists(__NAMESPACE__.'\Fixtures\NotPSR0bis', true));
+    }
+
+    public function testClassAlias()
+    {
+        $this->assertTrue(class_exists(Fixtures\ClassAlias::class, true));
+    }
+
+    /**
+     * @dataProvider provideDeprecatedSuper
+     */
+    public function testDeprecatedSuper($class, $super, $type)
+    {
+        set_error_handler(function () { return false; });
+        $e = error_reporting(0);
+        @trigger_error('', E_USER_DEPRECATED);
+
+        class_exists('Test\\'.__NAMESPACE__.'\\'.$class, true);
+
+        error_reporting($e);
+        restore_error_handler();
+
+        $lastError = error_get_last();
+        unset($lastError['file'], $lastError['line']);
+
+        $xError = [
+            'type' => E_USER_DEPRECATED,
+            'message' => 'The "Test\Symfony\Component\Debug\Tests\\'.$class.'" class '.$type.' "Symfony\Component\Debug\Tests\Fixtures\\'.$super.'" that is deprecated but this is a test deprecation notice.',
+        ];
+
+        $this->assertSame($xError, $lastError);
+    }
+
+    public function provideDeprecatedSuper()
+    {
+        return [
+            ['DeprecatedInterfaceClass', 'DeprecatedInterface', 'implements'],
+            ['DeprecatedParentClass', 'DeprecatedClass', 'extends'],
+        ];
+    }
+
+    public function testInterfaceExtendsDeprecatedInterface()
+    {
+        set_error_handler(function () { return false; });
+        $e = error_reporting(0);
+        trigger_error('', E_USER_NOTICE);
+
+        class_exists('Test\\'.NonDeprecatedInterfaceClass::class, true);
+
+        error_reporting($e);
+        restore_error_handler();
+
+        $lastError = error_get_last();
+        unset($lastError['file'], $lastError['line']);
+
+        $xError = [
+            'type' => E_USER_NOTICE,
+            'message' => '',
+        ];
+
+        $this->assertSame($xError, $lastError);
+    }
+
+    public function testDeprecatedSuperInSameNamespace()
+    {
+        set_error_handler(function () { return false; });
+        $e = error_reporting(0);
+        trigger_error('', E_USER_NOTICE);
+
+        class_exists('Symfony\Bridge\Debug\Tests\Fixtures\ExtendsDeprecatedParent', true);
+
+        error_reporting($e);
+        restore_error_handler();
+
+        $lastError = error_get_last();
+        unset($lastError['file'], $lastError['line']);
+
+        $xError = [
+            'type' => E_USER_NOTICE,
+            'message' => '',
+        ];
+
+        $this->assertSame($xError, $lastError);
+    }
+
+    public function testReservedForPhp7()
+    {
+        if (\PHP_VERSION_ID >= 70000) {
+            $this->markTestSkipped('PHP7 already prevents using reserved names.');
+        }
+
+        set_error_handler(function () { return false; });
+        $e = error_reporting(0);
+        trigger_error('', E_USER_NOTICE);
+
+        class_exists('Test\\'.Float::class, true);
+
+        error_reporting($e);
+        restore_error_handler();
+
+        $lastError = error_get_last();
+        unset($lastError['file'], $lastError['line']);
+
+        $xError = [
+            'type' => E_USER_DEPRECATED,
+            '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()
+    {
+        $deprecations = [];
+        set_error_handler(function ($type, $msg) use (&$deprecations) { $deprecations[] = $msg; });
+        $e = error_reporting(E_USER_DEPRECATED);
+
+        require __DIR__.'/Fixtures/FinalClasses.php';
+
+        $i = 1;
+        while (class_exists($finalClass = Fixtures\FinalClass::class.$i++, false)) {
+            spl_autoload_call($finalClass);
+            class_exists('Test\\'.__NAMESPACE__.'\\Extends'.substr($finalClass, strrpos($finalClass, '\\') + 1), true);
+        }
+
+        error_reporting($e);
+        restore_error_handler();
+
+        $this->assertSame([
+            'The "Symfony\Component\Debug\Tests\Fixtures\FinalClass1" 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\ExtendsFinalClass1".',
+            'The "Symfony\Component\Debug\Tests\Fixtures\FinalClass2" class is considered final. It may change without further notice as of its next major version. You should not extend it from "Test\Symfony\Component\Debug\Tests\ExtendsFinalClass2".',
+            'The "Symfony\Component\Debug\Tests\Fixtures\FinalClass3" class is considered final comment with @@@ and ***. It may change without further notice as of its next major version. You should not extend it from "Test\Symfony\Component\Debug\Tests\ExtendsFinalClass3".',
+            'The "Symfony\Component\Debug\Tests\Fixtures\FinalClass4" class is considered final. It may change without further notice as of its next major version. You should not extend it from "Test\Symfony\Component\Debug\Tests\ExtendsFinalClass4".',
+            'The "Symfony\Component\Debug\Tests\Fixtures\FinalClass5" class is considered final multiline comment. It may change without further notice as of its next major version. You should not extend it from "Test\Symfony\Component\Debug\Tests\ExtendsFinalClass5".',
+            'The "Symfony\Component\Debug\Tests\Fixtures\FinalClass6" class is considered final. It may change without further notice as of its next major version. You should not extend it from "Test\Symfony\Component\Debug\Tests\ExtendsFinalClass6".',
+            'The "Symfony\Component\Debug\Tests\Fixtures\FinalClass7" class is considered final another multiline comment... It may change without further notice as of its next major version. You should not extend it from "Test\Symfony\Component\Debug\Tests\ExtendsFinalClass7".',
+            'The "Symfony\Component\Debug\Tests\Fixtures\FinalClass8" class is considered final. It may change without further notice as of its next major version. You should not extend it from "Test\Symfony\Component\Debug\Tests\ExtendsFinalClass8".',
+        ], $deprecations);
+    }
+
+    public function testExtendedFinalMethod()
+    {
+        $deprecations = [];
+        set_error_handler(function ($type, $msg) use (&$deprecations) { $deprecations[] = $msg; });
+        $e = error_reporting(E_USER_DEPRECATED);
+
+        class_exists(Fixtures\ExtendedFinalMethod::class, true);
+
+        error_reporting($e);
+        restore_error_handler();
+
+        $xError = [
+            '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".',
+            '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".',
+        ];
+
+        $this->assertSame($xError, $deprecations);
+    }
+
+    public function testExtendedDeprecatedMethodDoesntTriggerAnyNotice()
+    {
+        set_error_handler(function () { return false; });
+        $e = error_reporting(0);
+        trigger_error('', E_USER_NOTICE);
+
+        class_exists('Test\\'.ExtendsAnnotatedClass::class, true);
+
+        error_reporting($e);
+        restore_error_handler();
+
+        $lastError = error_get_last();
+        unset($lastError['file'], $lastError['line']);
+
+        $this->assertSame(['type' => E_USER_NOTICE, 'message' => ''], $lastError);
+    }
+
+    public function testInternalsUse()
+    {
+        $deprecations = [];
+        set_error_handler(function ($type, $msg) use (&$deprecations) { $deprecations[] = $msg; });
+        $e = error_reporting(E_USER_DEPRECATED);
+
+        class_exists('Test\\'.ExtendsInternals::class, true);
+
+        error_reporting($e);
+        restore_error_handler();
+
+        $this->assertSame($deprecations, [
+            '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\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\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\InternalClass::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".',
+        ]);
+    }
+
+    public function testUseTraitWithInternalMethod()
+    {
+        $deprecations = [];
+        set_error_handler(function ($type, $msg) use (&$deprecations) { $deprecations[] = $msg; });
+        $e = error_reporting(E_USER_DEPRECATED);
+
+        class_exists('Test\\'.UseTraitWithInternalMethod::class, true);
+
+        error_reporting($e);
+        restore_error_handler();
+
+        $this->assertSame([], $deprecations);
+    }
+
+    public function testEvaluatedCode()
+    {
+        $this->assertTrue(class_exists(Fixtures\DefinitionInEvaluatedCode::class, true));
+    }
+}
+
+class ClassLoader
+{
+    public function loadClass($class)
+    {
+    }
+
+    public function getClassMap()
+    {
+        return [__NAMESPACE__.'\Fixtures\NotPSR0bis' => __DIR__.'/Fixtures/notPsr0Bis.php'];
+    }
+
+    public function findFile($class)
+    {
+        $fixtureDir = __DIR__.\DIRECTORY_SEPARATOR.'Fixtures'.\DIRECTORY_SEPARATOR;
+
+        if (TestingUnsilencing::class === $class) {
+            eval('-- parse error --');
+        } elseif (TestingStacking::class === $class) {
+            eval('namespace '.__NAMESPACE__.'; class TestingStacking { function foo() {} }');
+        } elseif (TestingCaseMismatch::class === $class) {
+            eval('namespace '.__NAMESPACE__.'; class TestingCaseMisMatch {}');
+        } 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 ('Symfony\Bridge\Debug\Tests\Fixtures\ExtendsDeprecatedParent' === $class) {
+            eval('namespace Symfony\Bridge\Debug\Tests\Fixtures; class ExtendsDeprecatedParent extends \\'.__NAMESPACE__.'\Fixtures\DeprecatedClass {}');
+        } elseif ('Test\\'.DeprecatedParentClass::class === $class) {
+            eval('namespace Test\\'.__NAMESPACE__.'; class DeprecatedParentClass extends \\'.__NAMESPACE__.'\Fixtures\DeprecatedClass {}');
+        } elseif ('Test\\'.DeprecatedInterfaceClass::class === $class) {
+            eval('namespace Test\\'.__NAMESPACE__.'; class DeprecatedInterfaceClass implements \\'.__NAMESPACE__.'\Fixtures\DeprecatedInterface {}');
+        } elseif ('Test\\'.NonDeprecatedInterfaceClass::class === $class) {
+            eval('namespace Test\\'.__NAMESPACE__.'; class NonDeprecatedInterfaceClass implements \\'.__NAMESPACE__.'\Fixtures\NonDeprecatedInterface {}');
+        } elseif ('Test\\'.Float::class === $class) {
+            eval('namespace Test\\'.__NAMESPACE__.'; class Float {}');
+        } elseif (0 === strpos($class, 'Test\\'.ExtendsFinalClass::class)) {
+            $classShortName = substr($class, strrpos($class, '\\') + 1);
+            eval('namespace Test\\'.__NAMESPACE__.'; class '.$classShortName.' extends \\'.__NAMESPACE__.'\Fixtures\\'.substr($classShortName, 7).' {}');
+        } elseif ('Test\\'.ExtendsAnnotatedClass::class === $class) {
+            eval('namespace Test\\'.__NAMESPACE__.'; class ExtendsAnnotatedClass extends \\'.__NAMESPACE__.'\Fixtures\AnnotatedClass {
+                public function deprecatedMethod() { }
+            }');
+        } elseif ('Test\\'.ExtendsInternals::class === $class) {
+            eval('namespace Test\\'.__NAMESPACE__.'; class ExtendsInternals extends ExtendsInternalsParent {
+                use \\'.__NAMESPACE__.'\Fixtures\InternalTrait;
+
+                public function internalMethod() { }
+            }');
+        } elseif ('Test\\'.ExtendsInternalsParent::class === $class) {
+            eval('namespace Test\\'.__NAMESPACE__.'; class ExtendsInternalsParent extends \\'.__NAMESPACE__.'\Fixtures\InternalClass implements \\'.__NAMESPACE__.'\Fixtures\InternalInterface { }');
+        } elseif ('Test\\'.UseTraitWithInternalMethod::class === $class) {
+            eval('namespace Test\\'.__NAMESPACE__.'; class UseTraitWithInternalMethod { use \\'.__NAMESPACE__.'\Fixtures\TraitWithInternalMethod; }');
+        }
+
+        return null;
+    }
+}

Tests/ErrorHandlerTest.php

@@ -11,210 +11,636 @@
 
 namespace Symfony\Component\Debug\Tests;
 
+use PHPUnit\Framework\TestCase;
+use Psr\Log\LogLevel;
+use Psr\Log\NullLogger;
+use Symfony\Component\Debug\BufferingLogger;
 use Symfony\Component\Debug\ErrorHandler;
-use Symfony\Component\Debug\Exception\DummyException;
+use Symfony\Component\Debug\Exception\SilencedErrorContext;
+use Symfony\Component\Debug\Tests\Fixtures\ErrorHandlerThatUsesThePreviousOne;
+use Symfony\Component\Debug\Tests\Fixtures\LoggerThatSetAnErrorHandler;
 
 /**
  * ErrorHandlerTest.
  *
  * @author Robert Schönthal <seroscho@googlemail.com>
+ * @author Nicolas Grekas <p@tchwork.com>
  */
-class ErrorHandlerTest extends \PHPUnit_Framework_TestCase
+class ErrorHandlerTest extends TestCase
 {
-    /**
-     * @var int Error reporting level before running tests.
-     */
-    protected $errorReporting;
-
-    protected function setUp()
+    public function testRegister()
     {
-        $this->errorReporting = error_reporting(E_ALL | E_STRICT);
-        $this->iniSet('display_errors', '1');
-    }
+        $handler = ErrorHandler::register();
 
-    protected function tearDown()
-    {
-        error_reporting($this->errorReporting);
-    }
-
-    public function testCompileTimeError()
-    {
-        // the ContextErrorException must not be loaded to test the workaround
-        // for https://bugs.php.net/bug.php?id=65322.
-        if (class_exists('Symfony\Component\Debug\Exception\ContextErrorException', false)) {
-            $this->markTestSkipped('The ContextErrorException class is already loaded.');
-        }
-
-        $exceptionHandler = $this->getMock('Symfony\Component\Debug\ExceptionHandler', array('handle'));
-
-        // the following code forces some PHPUnit classes to be loaded
-        // so that they will be available in the exception handler
-        // as they won't be autoloaded by PHP
-        class_exists('PHPUnit_Framework_MockObject_Invocation_Object');
-        $this->assertInstanceOf('stdClass', new \stdClass());
-        $this->assertEquals(1, 1);
-        $this->assertStringStartsWith('foo', 'foobar');
-        $this->assertArrayHasKey('bar', array('bar' => 'foo'));
-
-        $that = $this;
-        $exceptionCheck = function ($exception) use ($that) {
-            $that->assertInstanceOf('Symfony\Component\Debug\Exception\ContextErrorException', $exception);
-            $that->assertEquals(2, $exception->getLine());
-            if (PHP_VERSION_ID < 70000) {
-                $that->assertEquals(E_STRICT, $exception->getSeverity());
-                $that->assertStringStartsWith('Runtime Notice: Declaration of _CompileTimeError::foo() should be compatible with', $exception->getMessage());
-            } else {
-                $that->assertEquals(E_WARNING, $exception->getSeverity());
-                $that->assertStringStartsWith('Warning: Declaration of _CompileTimeError::foo() should be compatible with', $exception->getMessage());
-            }
-            $that->assertArrayHasKey('bar', $exception->getContext());
-        };
-
-        $exceptionHandler->expects($this->once())
-            ->method('handle')
-            ->will($this->returnCallback($exceptionCheck))
-        ;
-
-        ErrorHandler::register();
-        set_exception_handler(array($exceptionHandler, 'handle'));
-
-        // dummy variable to check for in error handler.
-        $bar = 123;
-
-        // trigger compile time error
         try {
-            eval(<<<'PHP'
-class _BaseCompileTimeError { function foo() {} }
-class _CompileTimeError extends _BaseCompileTimeError { function foo($invalid) {} }
-PHP
-            );
-        } catch (DummyException $e) {
-            // if an exception is thrown, the test passed
+            $this->assertInstanceOf('Symfony\Component\Debug\ErrorHandler', $handler);
+            $this->assertSame($handler, ErrorHandler::register());
+
+            $newHandler = new ErrorHandler();
+
+            $this->assertSame($handler, ErrorHandler::register($newHandler, false));
+            $h = set_error_handler('var_dump');
+            restore_error_handler();
+            $this->assertSame([$handler, 'handleError'], $h);
+
+            try {
+                $this->assertSame($newHandler, ErrorHandler::register($newHandler, true));
+                $h = set_error_handler('var_dump');
+                restore_error_handler();
+                $this->assertSame([$newHandler, 'handleError'], $h);
+            } catch (\Exception $e) {
+            }
+
+            restore_error_handler();
+            restore_exception_handler();
+
+            if (isset($e)) {
+                throw $e;
+            }
+        } catch (\Exception $e) {
         }
 
         restore_error_handler();
         restore_exception_handler();
+
+        if (isset($e)) {
+            throw $e;
+        }
+    }
+
+    public function testErrorGetLast()
+    {
+        $logger = $this->getMockBuilder('Psr\Log\LoggerInterface')->getMock();
+        $handler = ErrorHandler::register();
+        $handler->setDefaultLogger($logger);
+        $handler->screamAt(E_ALL);
+
+        try {
+            @trigger_error('Hello', E_USER_WARNING);
+            $expected = [
+                '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()
     {
-        $exceptionHandler = $this->getMock('Symfony\Component\Debug\ExceptionHandler', array('handle'));
-        set_exception_handler(array($exceptionHandler, 'handle'));
-
-        $that = $this;
-        $exceptionCheck = function ($exception) use ($that) {
-            $that->assertInstanceOf('Symfony\Component\Debug\Exception\ContextErrorException', $exception);
-            $that->assertEquals(E_NOTICE, $exception->getSeverity());
-            $that->assertEquals(__LINE__ + 40, $exception->getLine());
-            $that->assertEquals(__FILE__, $exception->getFile());
-            $that->assertRegexp('/^Notice: Undefined variable: (foo|bar)/', $exception->getMessage());
-            $that->assertArrayHasKey('foobar', $exception->getContext());
-
-            $trace = $exception->getTrace();
-            $that->assertEquals(__FILE__, $trace[0]['file']);
-            $that->assertEquals('Symfony\Component\Debug\ErrorHandler', $trace[0]['class']);
-            $that->assertEquals('handle', $trace[0]['function']);
-            $that->assertEquals('->', $trace[0]['type']);
-
-            $that->assertEquals(__FILE__, $trace[1]['file']);
-            $that->assertEquals(__CLASS__, $trace[1]['class']);
-            $that->assertEquals('triggerNotice', $trace[1]['function']);
-            $that->assertEquals('::', $trace[1]['type']);
-
-            $that->assertEquals(__CLASS__, $trace[2]['class']);
-            $that->assertEquals('testNotice', $trace[2]['function']);
-            $that->assertEquals('->', $trace[2]['type']);
-        };
-
-        $exceptionHandler->expects($this->once())
-            ->method('handle')
-            ->will($this->returnCallback($exceptionCheck));
         ErrorHandler::register();
 
         try {
             self::triggerNotice($this);
-        } catch (DummyException $e) {
+            $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());
 
-        restore_error_handler();
+            $trace = $exception->getTrace();
+
+            $this->assertEquals(__FILE__, $trace[0]['file']);
+            $this->assertEquals(__CLASS__, $trace[0]['class']);
+            $this->assertEquals('triggerNotice', $trace[0]['function']);
+            $this->assertEquals('::', $trace[0]['type']);
+
+            $this->assertEquals(__FILE__, $trace[0]['file']);
+            $this->assertEquals(__CLASS__, $trace[1]['class']);
+            $this->assertEquals(__FUNCTION__, $trace[1]['function']);
+            $this->assertEquals('->', $trace[1]['type']);
+        } finally {
+            restore_error_handler();
+            restore_exception_handler();
+        }
     }
 
     // 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);
     }
 
     public function testConstruct()
     {
-        $handler = ErrorHandler::register(3);
-
-        $level = new \ReflectionProperty($handler, 'level');
-        $level->setAccessible(true);
-
-        $this->assertEquals(3, $level->getValue($handler));
-
-        restore_error_handler();
+        try {
+            $handler = ErrorHandler::register();
+            $handler->throwAt(3, true);
+            $this->assertEquals(3 | E_RECOVERABLE_ERROR | E_USER_ERROR, $handler->throwAt(0));
+        } finally {
+            restore_error_handler();
+            restore_exception_handler();
+        }
     }
 
-    public function testHandle()
+    public function testDefaultLogger()
     {
-        $handler = ErrorHandler::register(0);
-        $this->assertFalse($handler->handle(0, 'foo', 'foo.php', 12, array()));
-
-        restore_error_handler();
-
-        $handler = ErrorHandler::register(3);
-        $this->assertFalse($handler->handle(4, 'foo', 'foo.php', 12, array()));
-
-        restore_error_handler();
-
-        $handler = ErrorHandler::register(3);
         try {
-            $handler->handle(111, 'foo', 'foo.php', 12, array());
-        } catch (\ErrorException $e) {
-            $this->assertSame('111: foo in foo.php line 12', $e->getMessage());
-            $this->assertSame(111, $e->getSeverity());
-            $this->assertSame('foo.php', $e->getFile());
-            $this->assertSame(12, $e->getLine());
+            $logger = $this->getMockBuilder('Psr\Log\LoggerInterface')->getMock();
+            $handler = ErrorHandler::register();
+
+            $handler->setDefaultLogger($logger, E_NOTICE);
+            $handler->setDefaultLogger($logger, [E_USER_NOTICE => LogLevel::CRITICAL]);
+
+            $loggers = [
+                E_DEPRECATED => [null, LogLevel::INFO],
+                E_USER_DEPRECATED => [null, LogLevel::INFO],
+                E_NOTICE => [$logger, LogLevel::WARNING],
+                E_USER_NOTICE => [$logger, LogLevel::CRITICAL],
+                E_STRICT => [null, LogLevel::WARNING],
+                E_WARNING => [null, LogLevel::WARNING],
+                E_USER_WARNING => [null, LogLevel::WARNING],
+                E_COMPILE_WARNING => [null, LogLevel::WARNING],
+                E_CORE_WARNING => [null, LogLevel::WARNING],
+                E_USER_ERROR => [null, LogLevel::CRITICAL],
+                E_RECOVERABLE_ERROR => [null, LogLevel::CRITICAL],
+                E_COMPILE_ERROR => [null, LogLevel::CRITICAL],
+                E_PARSE => [null, LogLevel::CRITICAL],
+                E_ERROR => [null, LogLevel::CRITICAL],
+                E_CORE_ERROR => [null, LogLevel::CRITICAL],
+            ];
+            $this->assertSame($loggers, $handler->setLoggers([]));
+        } finally {
+            restore_error_handler();
+            restore_exception_handler();
+        }
+    }
+
+    public function testHandleError()
+    {
+        try {
+            $handler = ErrorHandler::register();
+            $handler->throwAt(0, true);
+            $this->assertFalse($handler->handleError(0, 'foo', 'foo.php', 12, []));
+
+            restore_error_handler();
+            restore_exception_handler();
+
+            $handler = ErrorHandler::register();
+            $handler->throwAt(3, true);
+            $this->assertFalse($handler->handleError(4, 'foo', 'foo.php', 12, []));
+
+            restore_error_handler();
+            restore_exception_handler();
+
+            $handler = ErrorHandler::register();
+            $handler->throwAt(3, true);
+            try {
+                $handler->handleError(4, 'foo', 'foo.php', 12, []);
+            } catch (\ErrorException $e) {
+                $this->assertSame('Parse Error: foo', $e->getMessage());
+                $this->assertSame(4, $e->getSeverity());
+                $this->assertSame('foo.php', $e->getFile());
+                $this->assertSame(12, $e->getLine());
+            }
+
+            restore_error_handler();
+            restore_exception_handler();
+
+            $handler = ErrorHandler::register();
+            $handler->throwAt(E_USER_DEPRECATED, true);
+            $this->assertFalse($handler->handleError(E_USER_DEPRECATED, 'foo', 'foo.php', 12, []));
+
+            restore_error_handler();
+            restore_exception_handler();
+
+            $handler = ErrorHandler::register();
+            $handler->throwAt(E_DEPRECATED, true);
+            $this->assertFalse($handler->handleError(E_DEPRECATED, 'foo', 'foo.php', 12, []));
+
+            restore_error_handler();
+            restore_exception_handler();
+
+            $logger = $this->getMockBuilder('Psr\Log\LoggerInterface')->getMock();
+
+            $warnArgCheck = function ($logLevel, $message, $context) {
+                $this->assertEquals('info', $logLevel);
+                $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());
+            };
+
+            $logger
+                ->expects($this->once())
+                ->method('log')
+                ->willReturnCallback($warnArgCheck)
+            ;
+
+            $handler = ErrorHandler::register();
+            $handler->setDefaultLogger($logger, E_USER_DEPRECATED);
+            $this->assertTrue($handler->handleError(E_USER_DEPRECATED, 'foo', 'foo.php', 12, []));
+
+            restore_error_handler();
+            restore_exception_handler();
+
+            $logger = $this->getMockBuilder('Psr\Log\LoggerInterface')->getMock();
+
+            $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);
+            };
+
+            $logger
+                ->expects($this->once())
+                ->method('log')
+                ->willReturnCallback($logArgCheck)
+            ;
+
+            $handler = ErrorHandler::register();
+            $handler->setDefaultLogger($logger, E_NOTICE);
+            $handler->screamAt(E_NOTICE);
+            unset($undefVar);
+            $line = __LINE__ + 1;
+            @$undefVar++;
+
+            restore_error_handler();
+            restore_exception_handler();
+        } catch (\Exception $e) {
+            restore_error_handler();
+            restore_exception_handler();
+
+            throw $e;
+        }
+    }
+
+    public function testHandleUserError()
+    {
+        if (\PHP_VERSION_ID >= 70400) {
+            $this->markTestSkipped('PHP 7.4 allows __toString to throw exceptions');
         }
 
-        restore_error_handler();
+        try {
+            $handler = ErrorHandler::register();
+            $handler->throwAt(0, true);
 
-        $handler = ErrorHandler::register(E_USER_DEPRECATED);
-        $this->assertTrue($handler->handle(E_USER_DEPRECATED, 'foo', 'foo.php', 12, array()));
+            $e = null;
+            $x = new \Exception('Foo');
 
-        restore_error_handler();
+            try {
+                $f = new Fixtures\ToStringThrower($x);
+                $f .= ''; // Trigger $f->__toString()
+            } catch (\Exception $e) {
+            }
 
-        $handler = ErrorHandler::register(E_DEPRECATED);
-        $this->assertTrue($handler->handle(E_DEPRECATED, 'foo', 'foo.php', 12, array()));
+            $this->assertSame($x, $e);
+        } finally {
+            restore_error_handler();
+            restore_exception_handler();
+        }
+    }
 
-        restore_error_handler();
-
-        $logger = $this->getMock('Psr\Log\LoggerInterface');
-
-        $that = $this;
-        $warnArgCheck = function ($message, $context) use ($that) {
-            $that->assertEquals('foo', $message);
-            $that->assertArrayHasKey('type', $context);
-            $that->assertEquals($context['type'], ErrorHandler::TYPE_DEPRECATION);
-            $that->assertArrayHasKey('stack', $context);
-            $that->assertInternalType('array', $context['stack']);
+    public function testHandleDeprecation()
+    {
+        $logArgCheck = function ($level, $message, $context) {
+            $this->assertEquals(LogLevel::INFO, $level);
+            $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();
         $logger
             ->expects($this->once())
-            ->method('warning')
-            ->will($this->returnCallback($warnArgCheck))
+            ->method('log')
+            ->willReturnCallback($logArgCheck)
         ;
 
-        $handler = ErrorHandler::register(E_USER_DEPRECATED);
-        $handler->setLogger($logger);
-        $handler->handle(E_USER_DEPRECATED, 'foo', 'foo.php', 12, array());
+        $handler = new ErrorHandler();
+        $handler->setDefaultLogger($logger);
+        @$handler->handleError(E_USER_DEPRECATED, 'Foo deprecation', __FILE__, __LINE__, []);
 
         restore_error_handler();
     }
+
+    /**
+     * @group no-hhvm
+     */
+    public function testHandleException()
+    {
+        try {
+            $logger = $this->getMockBuilder('Psr\Log\LoggerInterface')->getMock();
+            $handler = ErrorHandler::register();
+
+            $exception = new \Exception('foo');
+
+            $logArgCheck = function ($level, $message, $context) {
+                $this->assertSame('Uncaught Exception: foo', $message);
+                $this->assertArrayHasKey('exception', $context);
+                $this->assertInstanceOf(\Exception::class, $context['exception']);
+            };
+
+            $logger
+                ->expects($this->exactly(2))
+                ->method('log')
+                ->willReturnCallback($logArgCheck)
+            ;
+
+            $handler->setDefaultLogger($logger, E_ERROR);
+
+            try {
+                $handler->handleException($exception);
+                $this->fail('Exception expected');
+            } catch (\Exception $e) {
+                $this->assertSame($exception, $e);
+            }
+
+            $handler->setExceptionHandler(function ($e) use ($exception) {
+                $this->assertSame($exception, $e);
+            });
+
+            $handler->handleException($exception);
+        } finally {
+            restore_error_handler();
+            restore_exception_handler();
+        }
+    }
+
+    /**
+     * @group legacy
+     */
+    public function testErrorStacking()
+    {
+        try {
+            $handler = ErrorHandler::register();
+            $handler->screamAt(E_USER_WARNING);
+
+            $logger = $this->getMockBuilder('Psr\Log\LoggerInterface')->getMock();
+
+            $logger
+                ->expects($this->exactly(2))
+                ->method('log')
+                ->withConsecutive(
+                    [$this->equalTo(LogLevel::WARNING), $this->equalTo('Dummy log')],
+                    [$this->equalTo(LogLevel::DEBUG), $this->equalTo('User Warning: Silenced warning')]
+                )
+            ;
+
+            $handler->setDefaultLogger($logger, [E_USER_WARNING => LogLevel::WARNING]);
+
+            ErrorHandler::stackErrors();
+            @trigger_error('Silenced warning', E_USER_WARNING);
+            $logger->log(LogLevel::WARNING, 'Dummy log');
+            ErrorHandler::unstackErrors();
+        } finally {
+            restore_error_handler();
+            restore_exception_handler();
+        }
+    }
+
+    public function testBootstrappingLogger()
+    {
+        $bootLogger = new BufferingLogger();
+        $handler = new ErrorHandler($bootLogger);
+
+        $loggers = [
+            E_DEPRECATED => [$bootLogger, LogLevel::INFO],
+            E_USER_DEPRECATED => [$bootLogger, LogLevel::INFO],
+            E_NOTICE => [$bootLogger, LogLevel::WARNING],
+            E_USER_NOTICE => [$bootLogger, LogLevel::WARNING],
+            E_STRICT => [$bootLogger, LogLevel::WARNING],
+            E_WARNING => [$bootLogger, LogLevel::WARNING],
+            E_USER_WARNING => [$bootLogger, LogLevel::WARNING],
+            E_COMPILE_WARNING => [$bootLogger, LogLevel::WARNING],
+            E_CORE_WARNING => [$bootLogger, LogLevel::WARNING],
+            E_USER_ERROR => [$bootLogger, LogLevel::CRITICAL],
+            E_RECOVERABLE_ERROR => [$bootLogger, LogLevel::CRITICAL],
+            E_COMPILE_ERROR => [$bootLogger, LogLevel::CRITICAL],
+            E_PARSE => [$bootLogger, LogLevel::CRITICAL],
+            E_ERROR => [$bootLogger, LogLevel::CRITICAL],
+            E_CORE_ERROR => [$bootLogger, LogLevel::CRITICAL],
+        ];
+
+        $this->assertSame($loggers, $handler->setLoggers([]));
+
+        $handler->handleError(E_DEPRECATED, 'Foo message', __FILE__, 123, []);
+
+        $logs = $bootLogger->cleanLogs();
+
+        $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(LogLevel::WARNING, 'Foo message', ['exception' => $exception]);
+
+        $mockLogger = $this->getMockBuilder('Psr\Log\LoggerInterface')->getMock();
+        $mockLogger->expects($this->once())
+            ->method('log')
+            ->with(LogLevel::WARNING, 'Foo message', ['exception' => $exception]);
+
+        $handler->setLoggers([E_DEPRECATED => [$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', ['exception' => $exception]);
+
+        $handler->setExceptionHandler(function () use ($handler, $mockLogger) {
+            $handler->setDefaultLogger($mockLogger);
+        });
+
+        $handler->handleException($exception);
+    }
+
+    /**
+     * @group no-hhvm
+     */
+    public function testHandleFatalError()
+    {
+        try {
+            $logger = $this->getMockBuilder('Psr\Log\LoggerInterface')->getMock();
+            $handler = ErrorHandler::register();
+
+            $error = [
+                'type' => E_PARSE,
+                'message' => 'foo',
+                'file' => 'bar',
+                'line' => 123,
+            ];
+
+            $logArgCheck = function ($level, $message, $context) {
+                $this->assertEquals('Fatal Parse Error: foo', $message);
+                $this->assertArrayHasKey('exception', $context);
+                $this->assertInstanceOf(\Exception::class, $context['exception']);
+            };
+
+            $logger
+                ->expects($this->once())
+                ->method('log')
+                ->willReturnCallback($logArgCheck)
+            ;
+
+            $handler->setDefaultLogger($logger, E_PARSE);
+
+            $handler->handleFatalError($error);
+
+            restore_error_handler();
+            restore_exception_handler();
+        } catch (\Exception $e) {
+            restore_error_handler();
+            restore_exception_handler();
+
+            throw $e;
+        }
+    }
+
+    /**
+     * @requires PHP 7
+     */
+    public function testHandleErrorException()
+    {
+        $exception = new \Error("Class 'IReallyReallyDoNotExistAnywhereInTheRepositoryISwear' not found");
+
+        $handler = new ErrorHandler();
+        $handler->setExceptionHandler(function () use (&$args) {
+            $args = \func_get_args();
+        });
+
+        $handler->handleException($exception);
+
+        $this->assertInstanceOf('Symfony\Component\Debug\Exception\ClassNotFoundException', $args[0]);
+        $this->assertStringStartsWith("Attempted to load class \"IReallyReallyDoNotExistAnywhereInTheRepositoryISwear\" from the global namespace.\nDid you forget a \"use\" statement", $args[0]->getMessage());
+    }
+
+    /**
+     * @group no-hhvm
+     */
+    public function testHandleFatalErrorOnHHVM()
+    {
+        try {
+            $handler = ErrorHandler::register();
+
+            $logger = $this->getMockBuilder('Psr\Log\LoggerInterface')->getMock();
+            $logger
+                ->expects($this->once())
+                ->method('log')
+                ->with(
+                    $this->equalTo(LogLevel::CRITICAL),
+                    $this->equalTo('Fatal Error: foo')
+                )
+            ;
+
+            $handler->setDefaultLogger($logger, E_ERROR);
+
+            $error = [
+                'type' => E_ERROR + 0x1000000, // This error level is used by HHVM for fatal errors
+                'message' => 'foo',
+                'file' => 'bar',
+                'line' => 123,
+                'context' => [123],
+                'backtrace' => [456],
+            ];
+
+            \call_user_func_array([$handler, 'handleError'], $error);
+            $handler->handleFatalError($error);
+        } finally {
+            restore_error_handler();
+            restore_exception_handler();
+        }
+    }
+
+    /**
+     * @group no-hhvm
+     */
+    public function testCustomExceptionHandler()
+    {
+        $this->expectException('Exception');
+        $handler = new ErrorHandler();
+        $handler->setExceptionHandler(function ($e) use ($handler) {
+            $handler->handleException($e);
+        });
+
+        $handler->handleException(new \Exception());
+    }
+
+    /**
+     * @dataProvider errorHandlerWhenLoggingProvider
+     */
+    public function testErrorHandlerWhenLogging($previousHandlerWasDefined, $loggerSetsAnotherHandler, $nextHandlerIsDefined)
+    {
+        try {
+            if ($previousHandlerWasDefined) {
+                set_error_handler('count');
+            }
+
+            $logger = $loggerSetsAnotherHandler ? new LoggerThatSetAnErrorHandler() : new NullLogger();
+
+            $handler = ErrorHandler::register();
+            $handler->setDefaultLogger($logger);
+
+            if ($nextHandlerIsDefined) {
+                $handler = ErrorHandlerThatUsesThePreviousOne::register();
+            }
+
+            @trigger_error('foo', E_USER_DEPRECATED);
+            @trigger_error('bar', E_USER_DEPRECATED);
+
+            $this->assertSame([$handler, 'handleError'], set_error_handler('var_dump'));
+
+            if ($logger instanceof LoggerThatSetAnErrorHandler) {
+                $this->assertCount(2, $logger->cleanLogs());
+            }
+
+            restore_error_handler();
+
+            if ($previousHandlerWasDefined) {
+                restore_error_handler();
+            }
+
+            if ($nextHandlerIsDefined) {
+                restore_error_handler();
+            }
+        } finally {
+            restore_error_handler();
+            restore_exception_handler();
+        }
+    }
+
+    public function errorHandlerWhenLoggingProvider()
+    {
+        foreach ([false, true] as $previousHandlerWasDefined) {
+            foreach ([false, true] as $loggerSetsAnotherHandler) {
+                foreach ([false, true] as $nextHandlerIsDefined) {
+                    yield [$previousHandlerWasDefined, $loggerSetsAnotherHandler, $nextHandlerIsDefined];
+                }
+            }
+        }
+    }
 }

Tests/Exception/FlattenExceptionTest.php

@@ -11,23 +11,25 @@
 
 namespace Symfony\Component\Debug\Tests\Exception;
 
+use PHPUnit\Framework\TestCase;
 use Symfony\Component\Debug\Exception\FlattenException;
-use Symfony\Component\HttpKernel\Exception\NotFoundHttpException;
-use Symfony\Component\HttpKernel\Exception\MethodNotAllowedHttpException;
-use Symfony\Component\HttpKernel\Exception\UnauthorizedHttpException;
-use Symfony\Component\HttpKernel\Exception\BadRequestHttpException;
-use Symfony\Component\HttpKernel\Exception\NotAcceptableHttpException;
-use Symfony\Component\HttpKernel\Exception\ConflictHttpException;
+use Symfony\Component\HttpFoundation\Exception\SuspiciousOperationException;
 use Symfony\Component\HttpKernel\Exception\AccessDeniedHttpException;
+use Symfony\Component\HttpKernel\Exception\BadRequestHttpException;
+use Symfony\Component\HttpKernel\Exception\ConflictHttpException;
 use Symfony\Component\HttpKernel\Exception\GoneHttpException;
 use Symfony\Component\HttpKernel\Exception\LengthRequiredHttpException;
+use Symfony\Component\HttpKernel\Exception\MethodNotAllowedHttpException;
+use Symfony\Component\HttpKernel\Exception\NotAcceptableHttpException;
+use Symfony\Component\HttpKernel\Exception\NotFoundHttpException;
 use Symfony\Component\HttpKernel\Exception\PreconditionFailedHttpException;
 use Symfony\Component\HttpKernel\Exception\PreconditionRequiredHttpException;
 use Symfony\Component\HttpKernel\Exception\ServiceUnavailableHttpException;
 use Symfony\Component\HttpKernel\Exception\TooManyRequestsHttpException;
+use Symfony\Component\HttpKernel\Exception\UnauthorizedHttpException;
 use Symfony\Component\HttpKernel\Exception\UnsupportedMediaTypeHttpException;
 
-class FlattenExceptionTest extends \PHPUnit_Framework_TestCase
+class FlattenExceptionTest extends TestCase
 {
     public function testStatusCode()
     {
@@ -52,7 +54,7 @@ class FlattenExceptionTest extends \PHPUnit_Framework_TestCase
         $flattened = FlattenException::create(new ConflictHttpException());
         $this->assertEquals('409', $flattened->getStatusCode());
 
-        $flattened = FlattenException::create(new MethodNotAllowedHttpException(array('POST')));
+        $flattened = FlattenException::create(new MethodNotAllowedHttpException(['POST']));
         $this->assertEquals('405', $flattened->getStatusCode());
 
         $flattened = FlattenException::create(new AccessDeniedHttpException());
@@ -78,33 +80,38 @@ 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()
     {
-        $flattened = FlattenException::create(new MethodNotAllowedHttpException(array('POST')));
-        $this->assertEquals(array('Allow' => 'POST'), $flattened->getHeaders());
+        $flattened = FlattenException::create(new MethodNotAllowedHttpException(['POST']));
+        $this->assertEquals(['Allow' => 'POST'], $flattened->getHeaders());
 
         $flattened = FlattenException::create(new UnauthorizedHttpException('Basic realm="My Realm"'));
-        $this->assertEquals(array('WWW-Authenticate' => 'Basic realm="My Realm"'), $flattened->getHeaders());
+        $this->assertEquals(['WWW-Authenticate' => 'Basic realm="My Realm"'], $flattened->getHeaders());
 
         $flattened = FlattenException::create(new ServiceUnavailableHttpException('Fri, 31 Dec 1999 23:59:59 GMT'));
-        $this->assertEquals(array('Retry-After' => 'Fri, 31 Dec 1999 23:59:59 GMT'), $flattened->getHeaders());
+        $this->assertEquals(['Retry-After' => 'Fri, 31 Dec 1999 23:59:59 GMT'], $flattened->getHeaders());
 
         $flattened = FlattenException::create(new ServiceUnavailableHttpException(120));
-        $this->assertEquals(array('Retry-After' => 120), $flattened->getHeaders());
+        $this->assertEquals(['Retry-After' => 120], $flattened->getHeaders());
 
         $flattened = FlattenException::create(new TooManyRequestsHttpException('Fri, 31 Dec 1999 23:59:59 GMT'));
-        $this->assertEquals(array('Retry-After' => 'Fri, 31 Dec 1999 23:59:59 GMT'), $flattened->getHeaders());
+        $this->assertEquals(['Retry-After' => 'Fri, 31 Dec 1999 23:59:59 GMT'], $flattened->getHeaders());
 
         $flattened = FlattenException::create(new TooManyRequestsHttpException(120));
-        $this->assertEquals(array('Retry-After' => 120), $flattened->getHeaders());
+        $this->assertEquals(['Retry-After' => 120], $flattened->getHeaders());
     }
 
     /**
      * @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);
@@ -128,7 +135,21 @@ class FlattenExceptionTest extends \PHPUnit_Framework_TestCase
 
         $this->assertSame($flattened2, $flattened->getPrevious());
 
-        $this->assertSame(array($flattened2), $flattened->getAllPrevious());
+        $this->assertSame([$flattened2], $flattened->getAllPrevious());
+    }
+
+    /**
+     * @requires PHP 7.0
+     */
+    public function testPreviousError()
+    {
+        $exception = new \Exception('test', 123, new \ParseError('Oh noes!', 42));
+
+        $flattened = FlattenException::create($exception)->getPrevious();
+
+        $this->assertEquals($flattened->getMessage(), 'Parse error: Oh noes!', 'The message is copied from the original exception.');
+        $this->assertEquals($flattened->getCode(), 42, 'The code is copied from the original exception.');
+        $this->assertEquals($flattened->getClass(), 'Symfony\Component\Debug\Exception\FatalThrowableError', 'The class is set to the class of the original exception');
     }
 
     /**
@@ -152,46 +173,121 @@ 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);
+        $flattened->setTrace([], 'foo.php', 123);
 
-        $this->assertEquals(array(
-            array(
+        $this->assertEquals([
+            [
                 'message' => 'test',
                 'class' => 'Exception',
-                'trace' => array(array(
+                'trace' => [[
                     'namespace' => '', 'short_class' => '', 'class' => '', 'type' => '', 'function' => '', 'file' => 'foo.php', 'line' => 123,
-                    'args' => array(),
-                )),
-            ),
-        ), $flattened->toArray());
+                    'args' => [],
+                ]],
+            ],
+        ], $flattened->toArray());
     }
 
     public function flattenDataProvider()
     {
-        return array(
-            array(new \Exception('test', 123), 500),
-        );
+        return [
+            [new \Exception('test', 123)],
+        ];
+    }
+
+    public function testArguments()
+    {
+        if (\PHP_VERSION_ID >= 70400) {
+            $this->markTestSkipped('PHP 7.4 removes arguments from exception traces.');
+        }
+
+        $dh = opendir(__DIR__);
+        $fh = tmpfile();
+
+        $incomplete = unserialize('O:14:"BogusTestClass":0:{}');
+
+        $exception = $this->createException([
+            (object) ['foo' => 1],
+            new NotFoundHttpException(),
+            $incomplete,
+            $dh,
+            $fh,
+            function () {},
+            [1, 2],
+            ['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(['object', 'stdClass'], $array[$i++]);
+        $this->assertSame(['object', 'Symfony\Component\HttpKernel\Exception\NotFoundHttpException'], $array[$i++]);
+        $this->assertSame(['incomplete-object', 'BogusTestClass'], $array[$i++]);
+        $this->assertSame(['resource', \defined('HHVM_VERSION') ? 'Directory' : 'stream'], $array[$i++]);
+        $this->assertSame(['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', [['integer', 1], ['integer', 2]]], $array[$i++]);
+        $this->assertSame(['array', ['foo' => ['integer', 123]]], $array[$i++]);
+        $this->assertSame(['null', null], $array[$i++]);
+        $this->assertSame(['boolean', true], $array[$i++]);
+        $this->assertSame(['boolean', false], $array[$i++]);
+        $this->assertSame(['integer', 0], $array[$i++]);
+        $this->assertSame(['float', 0.0], $array[$i++]);
+        $this->assertSame(['string', '0'], $array[$i++]);
+        $this->assertSame(['string', ''], $array[$i++]);
+        $this->assertSame(['float', INF], $array[$i++]);
+
+        // assertEquals() does not like NAN values.
+        $this->assertEquals($array[$i][0], 'float');
+        $this->assertNan($array[$i][1]);
     }
 
     public function testRecursionInArguments()
     {
-        $a = array('foo', array(2, &$a));
+        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()
     {
-        $a = array();
-        for ($i = 0; $i < 20; $i++) {
-            for ($j = 0; $j < 50; $j++) {
-                for ($k = 0; $k < 10; $k++) {
+        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) {
+                for ($k = 0; $k < 10; ++$k) {
                     $a[$i][$j][$k] = 'value';
                 }
             }
@@ -202,55 +298,17 @@ class FlattenExceptionTest extends \PHPUnit_Framework_TestCase
 
         $flattened = FlattenException::create($exception);
         $trace = $flattened->getTrace();
+
+        $this->assertSame($trace[1]['args'][0], ['array', ['array', '*SKIPPED over 10000 entries*']]);
+
         $serializeTrace = serialize($trace);
 
-        $this->assertContains('*SKIPPED over 10000 entries*', $serializeTrace);
-        $this->assertNotContains('*value1*', $serializeTrace);
+        $this->assertStringContainsString('*SKIPPED over 10000 entries*', $serializeTrace);
+        $this->assertStringNotContainsString('*value1*', $serializeTrace);
     }
 
     private function createException($foo)
     {
         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());
-    }
 }

Tests/ExceptionHandlerTest.php

@@ -11,52 +11,153 @@
 
 namespace Symfony\Component\Debug\Tests;
 
+use PHPUnit\Framework\TestCase;
+use Symfony\Component\Debug\Exception\OutOfMemoryException;
 use Symfony\Component\Debug\ExceptionHandler;
-use Symfony\Component\HttpKernel\Exception\NotFoundHttpException;
 use Symfony\Component\HttpKernel\Exception\MethodNotAllowedHttpException;
+use Symfony\Component\HttpKernel\Exception\NotFoundHttpException;
 
-class ExceptionHandlerTest extends \PHPUnit_Framework_TestCase
+require_once __DIR__.'/HeaderMock.php';
+
+class ExceptionHandlerTest extends TestCase
 {
+    protected function setUp()
+    {
+        testHeader();
+    }
+
+    protected function tearDown()
+    {
+        testHeader();
+    }
+
     public function testDebug()
     {
         $handler = new ExceptionHandler(false);
-        $response = $handler->createResponse(new \RuntimeException('Foo'));
 
-        $this->assertContains('<h1>Whoops, looks like something went wrong.</h1>', $response->getContent());
-        $this->assertNotContains('<div class="block_exception clear_fix">', $response->getContent());
+        ob_start();
+        $handler->sendPhpResponse(new \RuntimeException('Foo'));
+        $response = ob_get_clean();
+
+        $this->assertStringContainsString('Whoops, looks like something went wrong.', $response);
+        $this->assertStringNotContainsString('<div class="trace trace-as-html">', $response);
 
         $handler = new ExceptionHandler(true);
-        $response = $handler->createResponse(new \RuntimeException('Foo'));
 
-        $this->assertContains('<h1>Whoops, looks like something went wrong.</h1>', $response->getContent());
-        $this->assertContains('<div class="block_exception clear_fix">', $response->getContent());
+        ob_start();
+        $handler->sendPhpResponse(new \RuntimeException('Foo'));
+        $response = ob_get_clean();
+
+        $this->assertStringContainsString('Whoops, looks like something went wrong.', $response);
+        $this->assertStringContainsString('<div class="trace trace-as-html">', $response);
     }
 
     public function testStatusCode()
     {
-        $handler = new ExceptionHandler(false);
+        $handler = new ExceptionHandler(false, 'iso8859-1');
 
-        $response = $handler->createResponse(new \RuntimeException('Foo'));
-        $this->assertEquals('500', $response->getStatusCode());
-        $this->assertContains('Whoops, looks like something went wrong.', $response->getContent());
+        ob_start();
+        $handler->sendPhpResponse(new NotFoundHttpException('Foo'));
+        $response = ob_get_clean();
 
-        $response = $handler->createResponse(new NotFoundHttpException('Foo'));
-        $this->assertEquals('404', $response->getStatusCode());
-        $this->assertContains('Sorry, the page you are looking for could not be found.', $response->getContent());
+        $this->assertStringContainsString('Sorry, the page you are looking for could not be found.', $response);
+
+        $expectedHeaders = [
+            ['HTTP/1.0 404', true, null],
+            ['Content-Type: text/html; charset=iso8859-1', true, null],
+        ];
+
+        $this->assertSame($expectedHeaders, testHeader());
     }
 
     public function testHeaders()
     {
-        $handler = new ExceptionHandler(false);
+        $handler = new ExceptionHandler(false, 'iso8859-1');
 
-        $response = $handler->createResponse(new MethodNotAllowedHttpException(array('POST')));
-        $this->assertEquals('405', $response->getStatusCode());
-        $this->assertEquals('POST', $response->headers->get('Allow'));
+        ob_start();
+        $handler->sendPhpResponse(new MethodNotAllowedHttpException(['POST']));
+        ob_get_clean();
+
+        $expectedHeaders = [
+            ['HTTP/1.0 405', true, null],
+            ['Allow: POST', false, null],
+            ['Content-Type: text/html; charset=iso8859-1', true, null],
+        ];
+
+        $this->assertSame($expectedHeaders, testHeader());
     }
 
     public function testNestedExceptions()
     {
         $handler = new ExceptionHandler(true);
-        $response = $handler->createResponse(new \RuntimeException('Foo', 0, new \RuntimeException('Bar')));
+        ob_start();
+        $handler->sendPhpResponse(new \RuntimeException('Foo', 0, new \RuntimeException('Bar')));
+        $response = ob_get_clean();
+
+        $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()
+    {
+        $handler = new ExceptionHandler(true);
+        ob_start();
+
+        $handler->handle(new \Exception('foo'));
+
+        $this->assertThatTheExceptionWasOutput(ob_get_clean(), \Exception::class, 'Exception', 'foo');
+    }
+
+    public function testHandleWithACustomHandlerThatOutputsSomething()
+    {
+        $handler = new ExceptionHandler(true);
+        ob_start();
+        $handler->setHandler(function () {
+            echo 'ccc';
+        });
+
+        $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()
+    {
+        $handler = new ExceptionHandler(true);
+        ob_start();
+        $handler->setHandler(function () {
+            $this->fail('OutOfMemoryException should bypass the handler');
+        });
+
+        $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

@@ -0,0 +1,184 @@
+<?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\FatalErrorHandler;
+
+use Composer\Autoload\ClassLoader as ComposerClassLoader;
+use PHPUnit\Framework\TestCase;
+use Symfony\Component\Debug\DebugClassLoader;
+use Symfony\Component\Debug\Exception\FatalErrorException;
+use Symfony\Component\Debug\FatalErrorHandler\ClassNotFoundFatalErrorHandler;
+
+class ClassNotFoundFatalErrorHandlerTest extends TestCase
+{
+    public static function setUpBeforeClass()
+    {
+        foreach (spl_autoload_functions() as $function) {
+            if (!\is_array($function)) {
+                continue;
+            }
+
+            // get class loaders wrapped by DebugClassLoader
+            if ($function[0] instanceof DebugClassLoader) {
+                $function = $function[0]->getClassLoader();
+
+                if (!\is_array($function)) {
+                    continue;
+                }
+            }
+
+            if ($function[0] instanceof ComposerClassLoader) {
+                $function[0]->add('Symfony_Component_Debug_Tests_Fixtures', \dirname(\dirname(\dirname(\dirname(\dirname(__DIR__))))));
+                break;
+            }
+        }
+    }
+
+    /**
+     * @dataProvider provideClassNotFoundData
+     */
+    public function testHandleClassNotFound($error, $translatedMessage, $autoloader = null)
+    {
+        if ($autoloader) {
+            // Unregister all autoloaders to ensure the custom provided
+            // autoloader is the only one to be used during the test run.
+            $autoloaders = spl_autoload_functions();
+            array_map('spl_autoload_unregister', $autoloaders);
+            spl_autoload_register($autoloader);
+        }
+
+        $handler = new ClassNotFoundFatalErrorHandler();
+
+        $exception = $handler->handleError($error, new FatalErrorException('', 0, $error['type'], $error['file'], $error['line']));
+
+        if ($autoloader) {
+            spl_autoload_unregister($autoloader);
+            array_map('spl_autoload_register', $autoloaders);
+        }
+
+        $this->assertInstanceOf('Symfony\Component\Debug\Exception\ClassNotFoundException', $exception);
+        $this->assertRegExp($translatedMessage, $exception->getMessage());
+        $this->assertSame($error['type'], $exception->getSeverity());
+        $this->assertSame($error['file'], $exception->getFile());
+        $this->assertSame($error['line'], $exception->getLine());
+    }
+
+    public function provideClassNotFoundData()
+    {
+        $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']);
+
+        return [
+            [
+                [
+                    'type' => 1,
+                    'line' => 12,
+                    'file' => 'foo.php',
+                    'message' => 'Class \'WhizBangFactory\' not found',
+                ],
+                "/^Attempted to load class \"WhizBangFactory\" from the global namespace.\nDid you forget a \"use\" statement\?$/",
+            ],
+            [
+                [
+                    'type' => 1,
+                    'line' => 12,
+                    'file' => 'foo.php',
+                    'message' => 'Class \'Foo\\Bar\\WhizBangFactory\' not found',
+                ],
+                "/^Attempted to load class \"WhizBangFactory\" from namespace \"Foo\\\\Bar\".\nDid you forget a \"use\" statement for another namespace\?$/",
+            ],
+            [
+                [
+                    'type' => 1,
+                    'line' => 12,
+                    'file' => 'foo.php',
+                    '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'],
+            ],
+            [
+                [
+                    'type' => 1,
+                    'line' => 12,
+                    'file' => 'foo.php',
+                    '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'],
+            ],
+            [
+                [
+                    'type' => 1,
+                    'line' => 12,
+                    'file' => 'foo.php',
+                    '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'],
+            ],
+            [
+                [
+                    'type' => 1,
+                    'line' => 12,
+                    'file' => 'foo.php',
+                    '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\"\?$/",
+                [$autoloader, 'loadClass'],
+            ],
+            [
+                [
+                    'type' => 1,
+                    'line' => 12,
+                    'file' => 'foo.php',
+                    '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\"\?/",
+                [$debugClassLoader, 'loadClass'],
+            ],
+            [
+                [
+                    'type' => 1,
+                    'line' => 12,
+                    'file' => 'foo.php',
+                    'message' => 'Class \'Foo\\Bar\\UndefinedFunctionException\' not found',
+                ],
+                "/^Attempted to load class \"UndefinedFunctionException\" from namespace \"Foo\\\\Bar\".\nDid you forget a \"use\" statement for another namespace\?$/",
+                function ($className) { /* do nothing here */ },
+            ],
+        ];
+    }
+
+    public function testCannotRedeclareClass()
+    {
+        if (!file_exists(__DIR__.'/../FIXTURES2/REQUIREDTWICE.PHP')) {
+            $this->markTestSkipped('Can only be run on case insensitive filesystems');
+        }
+
+        require_once __DIR__.'/../FIXTURES2/REQUIREDTWICE.PHP';
+
+        $error = [
+            'type' => 1,
+            'line' => 12,
+            'file' => 'foo.php',
+            'message' => 'Class \'Foo\\Bar\\RequiredTwice\' not found',
+        ];
+
+        $handler = new ClassNotFoundFatalErrorHandler();
+        $exception = $handler->handleError($error, new FatalErrorException('', 0, $error['type'], $error['file'], $error['line']));
+
+        $this->assertInstanceOf('Symfony\Component\Debug\Exception\ClassNotFoundException', $exception);
+    }
+}

Tests/FatalErrorHandler/UndefinedFunctionFatalErrorHandlerTest.php

@@ -0,0 +1,81 @@
+<?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\FatalErrorHandler;
+
+use PHPUnit\Framework\TestCase;
+use Symfony\Component\Debug\Exception\FatalErrorException;
+use Symfony\Component\Debug\FatalErrorHandler\UndefinedFunctionFatalErrorHandler;
+
+class UndefinedFunctionFatalErrorHandlerTest extends TestCase
+{
+    /**
+     * @dataProvider provideUndefinedFunctionData
+     */
+    public function testUndefinedFunction($error, $translatedMessage)
+    {
+        $handler = new UndefinedFunctionFatalErrorHandler();
+        $exception = $handler->handleError($error, new FatalErrorException('', 0, $error['type'], $error['file'], $error['line']));
+
+        $this->assertInstanceOf('Symfony\Component\Debug\Exception\UndefinedFunctionException', $exception);
+        // class names are case insensitive and PHP/HHVM do not return the same
+        $this->assertSame(strtolower($translatedMessage), strtolower($exception->getMessage()));
+        $this->assertSame($error['type'], $exception->getSeverity());
+        $this->assertSame($error['file'], $exception->getFile());
+        $this->assertSame($error['line'], $exception->getLine());
+    }
+
+    public function provideUndefinedFunctionData()
+    {
+        return [
+            [
+                [
+                    'type' => 1,
+                    'line' => 12,
+                    'file' => 'foo.php',
+                    'message' => 'Call to undefined function test_namespaced_function()',
+                ],
+                "Attempted to call function \"test_namespaced_function\" from the global namespace.\nDid you mean to call \"\\symfony\\component\\debug\\tests\\fatalerrorhandler\\test_namespaced_function\"?",
+            ],
+            [
+                [
+                    'type' => 1,
+                    'line' => 12,
+                    'file' => 'foo.php',
+                    'message' => 'Call to undefined function Foo\\Bar\\Baz\\test_namespaced_function()',
+                ],
+                "Attempted to call function \"test_namespaced_function\" from namespace \"Foo\\Bar\\Baz\".\nDid you mean to call \"\\symfony\\component\\debug\\tests\\fatalerrorhandler\\test_namespaced_function\"?",
+            ],
+            [
+                [
+                    'type' => 1,
+                    'line' => 12,
+                    'file' => 'foo.php',
+                    'message' => 'Call to undefined function foo()',
+                ],
+                'Attempted to call function "foo" from the global namespace.',
+            ],
+            [
+                [
+                    'type' => 1,
+                    'line' => 12,
+                    'file' => 'foo.php',
+                    'message' => 'Call to undefined function Foo\\Bar\\Baz\\foo()',
+                ],
+                'Attempted to call function "foo" from namespace "Foo\Bar\Baz".',
+            ],
+        ];
+    }
+}
+
+function test_namespaced_function()
+{
+}

Tests/FatalErrorHandler/UndefinedMethodFatalErrorHandlerTest.php

@@ -0,0 +1,76 @@
+<?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\FatalErrorHandler;
+
+use PHPUnit\Framework\TestCase;
+use Symfony\Component\Debug\Exception\FatalErrorException;
+use Symfony\Component\Debug\FatalErrorHandler\UndefinedMethodFatalErrorHandler;
+
+class UndefinedMethodFatalErrorHandlerTest extends TestCase
+{
+    /**
+     * @dataProvider provideUndefinedMethodData
+     */
+    public function testUndefinedMethod($error, $translatedMessage)
+    {
+        $handler = new UndefinedMethodFatalErrorHandler();
+        $exception = $handler->handleError($error, new FatalErrorException('', 0, $error['type'], $error['file'], $error['line']));
+
+        $this->assertInstanceOf('Symfony\Component\Debug\Exception\UndefinedMethodException', $exception);
+        $this->assertSame($translatedMessage, $exception->getMessage());
+        $this->assertSame($error['type'], $exception->getSeverity());
+        $this->assertSame($error['file'], $exception->getFile());
+        $this->assertSame($error['line'], $exception->getLine());
+    }
+
+    public function provideUndefinedMethodData()
+    {
+        return [
+            [
+                [
+                    'type' => 1,
+                    'line' => 12,
+                    'file' => 'foo.php',
+                    'message' => 'Call to undefined method SplObjectStorage::what()',
+                ],
+                'Attempted to call an undefined method named "what" of class "SplObjectStorage".',
+            ],
+            [
+                [
+                    'type' => 1,
+                    'line' => 12,
+                    'file' => 'foo.php',
+                    'message' => 'Call to undefined method SplObjectStorage::walid()',
+                ],
+                "Attempted to call an undefined method named \"walid\" of class \"SplObjectStorage\".\nDid you mean to call \"valid\"?",
+            ],
+            [
+                [
+                    'type' => 1,
+                    'line' => 12,
+                    'file' => 'foo.php',
+                    'message' => 'Call to undefined method SplObjectStorage::offsetFet()',
+                ],
+                "Attempted to call an undefined method named \"offsetFet\" of class \"SplObjectStorage\".\nDid you mean to call e.g. \"offsetGet\", \"offsetSet\" or \"offsetUnset\"?",
+            ],
+            [
+                [
+                    'type' => 1,
+                    'message' => 'Call to undefined method class@anonymous::test()',
+                    'file' => '/home/possum/work/symfony/test.php',
+                    'line' => 11,
+                ],
+                'Attempted to call an undefined method named "test" of class "class@anonymous".',
+            ],
+        ];
+    }
+}

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()
+    {
+    }
+}

Tests/Fixtures/ClassAlias.php

@@ -0,0 +1,3 @@
+<?php
+
+class_alias('Symfony\Component\Debug\Tests\Fixtures\NotPSR0bis', 'Symfony\Component\Debug\Tests\Fixtures\ClassAlias');

Tests/Fixtures/DefinitionInEvaluatedCode.php

@@ -0,0 +1,11 @@
+<?php
+
+namespace Symfony\Component\Debug\Tests\Fixtures;
+
+eval('
+    namespace Symfony\Component\Debug\Tests\Fixtures;
+
+    class DefinitionInEvaluatedCode
+    {
+    }
+');

Tests/Fixtures/DeprecatedClass.php

@@ -0,0 +1,12 @@
+<?php
+
+namespace Symfony\Component\Debug\Tests\Fixtures;
+
+/**
+ * @deprecated but this is a test
+ *             deprecation notice
+ * @foobar
+ */
+class DeprecatedClass
+{
+}

Tests/Fixtures/DeprecatedInterface.php

@@ -0,0 +1,12 @@
+<?php
+
+namespace Symfony\Component\Debug\Tests\Fixtures;
+
+/**
+ * @deprecated but this is a test
+ *             deprecation notice
+ * @foobar
+ */
+interface DeprecatedInterface
+{
+}

Tests/Fixtures/ErrorHandlerThatUsesThePreviousOne.php

@@ -0,0 +1,22 @@
+<?php
+
+namespace Symfony\Component\Debug\Tests\Fixtures;
+
+class ErrorHandlerThatUsesThePreviousOne
+{
+    private static $previous;
+
+    public static function register()
+    {
+        $handler = new static();
+
+        self::$previous = set_error_handler([$handler, 'handleError']);
+
+        return $handler;
+    }
+
+    public function handleError($type, $message, $file, $line, $context)
+    {
+        return \call_user_func(self::$previous, $type, $message, $file, $line, $context);
+    }
+}

Tests/Fixtures/ExtendedFinalMethod.php

@@ -0,0 +1,19 @@
+<?php
+
+namespace Symfony\Component\Debug\Tests\Fixtures;
+
+class ExtendedFinalMethod extends FinalMethod
+{
+    use FinalMethod2Trait;
+
+    /**
+     * {@inheritdoc}
+     */
+    public function finalMethod()
+    {
+    }
+
+    public function anotherMethod()
+    {
+    }
+}

Tests/Fixtures/FinalClasses.php

@@ -0,0 +1,85 @@
+<?php
+
+namespace Symfony\Component\Debug\Tests\Fixtures;
+
+/**
+ * @final since version 3.3.
+ */
+class FinalClass1
+{
+    // simple comment
+}
+
+/**
+ * @final
+ */
+class FinalClass2
+{
+    // no comment
+}
+
+/**
+ * @final comment with @@@ and ***
+ *
+ * @author John Doe
+ */
+class FinalClass3
+{
+    // with comment and a tag after
+}
+
+/**
+ * @final
+ *
+ * @author John Doe
+ */
+class FinalClass4
+{
+    // without comment and a tag after
+}
+
+/**
+ * @author John Doe
+ *
+ *
+ * @final multiline
+ * comment
+ */
+class FinalClass5
+{
+    // with comment and a tag before
+}
+
+/**
+ * @author John Doe
+ *
+ * @final
+ */
+class FinalClass6
+{
+    // without comment and a tag before
+}
+
+/**
+ * @author John Doe
+ *
+ * @final another
+ *        multiline comment...
+ *
+ * @return string
+ */
+class FinalClass7
+{
+    // with comment and a tag before and after
+}
+
+/**
+ * @author John Doe
+ * @final
+ *
+ * @return string
+ */
+class FinalClass8
+{
+    // without comment and a tag before and after
+}

Tests/Fixtures/FinalMethod.php

@@ -0,0 +1,26 @@
+<?php
+
+namespace Symfony\Component\Debug\Tests\Fixtures;
+
+class FinalMethod
+{
+    /**
+     * @final since version 3.3.
+     */
+    public function finalMethod()
+    {
+    }
+
+    /**
+     * @final
+     *
+     * @return int
+     */
+    public function finalMethod2()
+    {
+    }
+
+    public function anotherMethod()
+    {
+    }
+}

Tests/Fixtures/FinalMethod2Trait.php

@@ -0,0 +1,10 @@
+<?php
+
+namespace Symfony\Component\Debug\Tests\Fixtures;
+
+trait FinalMethod2Trait
+{
+    public function finalMethod2()
+    {
+    }
+}

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()
+    {
+    }
+}

Tests/Fixtures/InternalInterface.php

@@ -0,0 +1,10 @@
+<?php
+
+namespace Symfony\Component\Debug\Tests\Fixtures;
+
+/**
+ * @internal
+ */
+interface InternalInterface
+{
+}

Tests/Fixtures/InternalTrait.php

@@ -0,0 +1,10 @@
+<?php
+
+namespace Symfony\Component\Debug\Tests\Fixtures;
+
+/**
+ * @internal
+ */
+trait InternalTrait
+{
+}

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()
+    {
+    }
+}

Tests/Fixtures/LoggerThatSetAnErrorHandler.php

@@ -0,0 +1,15 @@
+<?php
+
+namespace Symfony\Component\Debug\Tests\Fixtures;
+
+use Symfony\Component\Debug\BufferingLogger;
+
+class LoggerThatSetAnErrorHandler extends BufferingLogger
+{
+    public function log($level, $message, array $context = [])
+    {
+        set_error_handler('is_string');
+        parent::log($level, $message, $context);
+        restore_error_handler();
+    }
+}

Tests/Fixtures/NonDeprecatedInterface.php

@@ -0,0 +1,7 @@
+<?php
+
+namespace Symfony\Component\Debug\Tests\Fixtures;
+
+interface NonDeprecatedInterface extends DeprecatedInterface
+{
+}

Tests/Fixtures/PEARClass.php

@@ -0,0 +1,5 @@
+<?php
+
+class Symfony_Component_Debug_Tests_Fixtures_PEARClass
+{
+}

Tests/Fixtures/Throwing.php

@@ -0,0 +1,3 @@
+<?php
+
+throw new \Exception('boo');

Tests/Fixtures/ToStringThrower.php

@@ -0,0 +1,24 @@
+<?php
+
+namespace Symfony\Component\Debug\Tests\Fixtures;
+
+class ToStringThrower
+{
+    private $exception;
+
+    public function __construct(\Exception $e)
+    {
+        $this->exception = $e;
+    }
+
+    public function __toString()
+    {
+        try {
+            throw $this->exception;
+        } catch (\Exception $e) {
+            // Using user_error() here is on purpose so we do not forget
+            // that this alias also should work alongside with trigger_error().
+            return trigger_error($e, E_USER_ERROR);
+        }
+    }
+}

Tests/Fixtures/TraitWithInternalMethod.php

@@ -0,0 +1,13 @@
+<?php
+
+namespace Symfony\Component\Debug\Tests\Fixtures;
+
+trait TraitWithInternalMethod
+{
+    /**
+     * @internal
+     */
+    public function foo()
+    {
+    }
+}

Tests/Fixtures/casemismatch.php

@@ -0,0 +1,7 @@
+<?php
+
+namespace Symfony\Component\Debug\Tests\Fixtures;
+
+class CaseMismatch
+{
+}

Tests/Fixtures/notPsr0Bis.php

@@ -0,0 +1,7 @@
+<?php
+
+namespace Symfony\Component\Debug\Tests\Fixtures;
+
+class NotPSR0bis
+{
+}

Tests/Fixtures/psr4/Psr4CaseMismatch.php

@@ -0,0 +1,7 @@
+<?php
+
+namespace Symfony\Component\Debug\Tests\Fixtures;
+
+class PSR4CaseMismatch
+{
+}

Tests/Fixtures/reallyNotPsr0.php

@@ -0,0 +1,7 @@
+<?php
+
+namespace Symfony\Component\Debug\Tests\Fixtures;
+
+class NotPSR0
+{
+}

Tests/Fixtures2/RequiredTwice.php

@@ -0,0 +1,7 @@
+<?php
+
+namespace Symfony\Component\Debug\Tests\Fixtures2;
+
+class RequiredTwice
+{
+}

Tests/HeaderMock.php

@@ -0,0 +1,38 @@
+<?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;
+
+function headers_sent()
+{
+    return false;
+}
+
+function header($str, $replace = true, $status = null)
+{
+    Tests\testHeader($str, $replace, $status);
+}
+
+namespace Symfony\Component\Debug\Tests;
+
+function testHeader()
+{
+    static $headers = [];
+
+    if (!$h = \func_get_args()) {
+        $h = $headers;
+        $headers = [];
+
+        return $h;
+    }
+
+    $headers[] = \func_get_args();
+}

Tests/phpt/debug_class_loader.phpt

@@ -0,0 +1,27 @@
+--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".
+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

@@ -0,0 +1,47 @@
+--TEST--
+Test catching fatal errors when handlers are nested
+--INI--
+display_errors=0
+--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--
+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(%d) {%A}
+  ["previous":"Exception":private]=>
+  NULL
+  ["severity":protected]=>
+  int(1)
+}

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 = [])
+        {
+            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

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([
+    $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
+}

composer.json

@@ -16,29 +16,25 @@
         }
     ],
     "require": {
-        "php": ">=5.3.3"
+        "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/phpunit-bridge": "~2.7",
-        "symfony/http-kernel": "~2.3.24|~2.5.9|~2.6,>=2.6.2",
-        "symfony/http-foundation": "~2.1"
-    },
-    "suggest": {
-        "symfony/http-foundation": "",
-        "symfony/http-kernel": "",
-        "symfony/class-loader": ""
+        "symfony/http-kernel": "~2.8|~3.0|~4.0"
     },
     "autoload": {
-        "psr-0": { "Symfony\\Component\\Debug\\": "" }
+        "psr-4": { "Symfony\\Component\\Debug\\": "" },
+        "exclude-from-classmap": [
+            "/Tests/"
+        ]
     },
-    "target-dir": "Symfony/Component/Debug",
     "minimum-stability": "dev",
     "extra": {
         "branch-alias": {
-            "dev-master": "2.3-dev"
+            "dev-master": "3.4-dev"
         }
     }
 }

phpunit.xml.dist

@@ -1,18 +1,24 @@
 <?xml version="1.0" encoding="UTF-8"?>
 
 <phpunit xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
-         xsi:noNamespaceSchemaLocation="http://schema.phpunit.de/4.1/phpunit.xsd"
+         xsi:noNamespaceSchemaLocation="http://schema.phpunit.de/5.2/phpunit.xsd"
          backupGlobals="false"
          colors="true"
          bootstrap="vendor/autoload.php"
+         failOnRisky="true"
+         failOnWarning="true"
 >
     <php>
         <ini name="error_reporting" value="-1" />
     </php>
+
     <testsuites>
         <testsuite name="Symfony Debug Component Test Suite">
             <directory>./Tests/</directory>
         </testsuite>
+        <testsuite name="Symfony Debug Extension Test Suite">
+            <directory suffix=".phpt">./Resources/ext/tests/</directory>
+        </testsuite>
     </testsuites>
 
     <filter>