[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

DebugClassLoader.php

@@ -149,11 +149,11 @@ class DebugClassLoader
                 if (!$file = $this->classLoader[0]->findFile($class) ?: false) {
                     // no-op
                 } elseif (\function_exists('opcache_is_script_cached') && @opcache_is_script_cached($file)) {
-                    require $file;
+                    include $file;
 
                     return;
-                } else {
-                    require $file;
+                } elseif (false === include $file) {
+                    return;
                 }
             } else {
                 \call_user_func($this->classLoader, $class);
@@ -168,7 +168,7 @@ class DebugClassLoader
 
     private function checkClass($class, $file = null)
     {
-        $exists = null === $file || \class_exists($class, false) || \interface_exists($class, false) || \trait_exists($class, false);
+        $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);
@@ -186,13 +186,13 @@ class DebugClassLoader
             }
             $name = $refl->getName();
 
-            if ($name !== $class && 0 === \strcasecmp($name, $class)) {
+            if ($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())])) {
+            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());
             }
 
@@ -223,23 +223,23 @@ class DebugClassLoader
         $deprecations = [];
 
         // Don't trigger deprecations for classes in the same vendor
-        if (2 > $len = 1 + (\strpos($class, '\\') ?: \strpos($class, '_'))) {
+        if (2 > $len = 1 + (strpos($class, '\\') ?: strpos($class, '_'))) {
             $len = 0;
             $ns = '';
         } else {
-            $ns = \str_replace('_', '\\', \substr($class, 0, $len));
+            $ns = str_replace('_', '\\', substr($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, $notice)) {
+                if (false !== strpos($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);
+        $parent = get_parent_class($class);
         $parentAndOwnInterfaces = $this->getOwnInterfaces($class, $parent);
         if ($parent) {
             $parentAndOwnInterfaces[$parent] = $parent;
@@ -254,22 +254,22 @@ class DebugClassLoader
         }
 
         // Detect if the parent is annotated
-        foreach ($parentAndOwnInterfaces + \class_uses($class, false) as $use) {
+        foreach ($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[$class])) {
+            if (isset(self::$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), $len)) {
+            if (isset(self::$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($class)) {
+        if (trait_exists($class)) {
             return $deprecations;
         }
 
@@ -296,7 +296,7 @@ class DebugClassLoader
 
             if (isset(self::$internalMethods[$class][$method->name])) {
                 list($declaringClass, $message) = self::$internalMethods[$class][$method->name];
-                if (\strncmp($ns, $declaringClass, $len)) {
+                if (strncmp($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);
                 }
             }
@@ -307,7 +307,7 @@ class DebugClassLoader
             }
 
             foreach (['final', 'internal'] as $annotation) {
-                if (false !== \strpos($doc, $annotation) && preg_match('#\n\s+\* @'.$annotation.'(?:( .+?)\.?)?\r?\n\s+\*(?: @|/$|\r?\n)#s', $doc, $notice)) {
+                if (false !== strpos($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];
                 }
@@ -317,6 +317,12 @@ class DebugClassLoader
         return $deprecations;
     }
 
+    /**
+     * @param string $file
+     * @param string $class
+     *
+     * @return array|null
+     */
     public function checkCase(\ReflectionClass $refl, $file, $class)
     {
         $real = explode('\\', $class.strrchr($file, '.'));
@@ -333,7 +339,7 @@ class DebugClassLoader
         array_splice($tail, 0, $i + 1);
 
         if (!$tail) {
-            return;
+            return null;
         }
 
         $tail = \DIRECTORY_SEPARATOR.implode(\DIRECTORY_SEPARATOR, $tail);
@@ -349,6 +355,8 @@ class DebugClassLoader
         ) {
             return [substr($tail, -$tailLen + 1), substr($real, -$tailLen + 1), substr($real, 0, -$tailLen + 1)];
         }
+
+        return null;
     }
 
     /**
@@ -396,7 +404,7 @@ class DebugClassLoader
         }
 
         if (isset($dirFiles[$file])) {
-            return $real .= $dirFiles[$file];
+            return $real.$dirFiles[$file];
         }
 
         $kFile = strtolower($file);
@@ -415,7 +423,7 @@ class DebugClassLoader
             self::$darwinCache[$kDir][1] = $dirFiles;
         }
 
-        return $real .= $dirFiles[$kFile];
+        return $real.$dirFiles[$kFile];
     }
 
     /**

ErrorHandler.php

@@ -382,6 +382,10 @@ class ErrorHandler
      */
     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 & $type);
@@ -445,7 +449,7 @@ class ErrorHandler
                 self::$silencedErrorCache[$id][$message] = $errorAsException;
             }
             if (null === $lightTrace) {
-                return;
+                return true;
             }
         } else {
             if ($scope) {
@@ -465,7 +469,7 @@ class ErrorHandler
         }
 
         if ($throw) {
-            if (E_USER_ERROR & $type) {
+            if (\PHP_VERSION_ID < 70400 && E_USER_ERROR & $type) {
                 for ($i = 1; isset($backtrace[$i]); ++$i) {
                     if (isset($backtrace[$i]['function'], $backtrace[$i]['type'], $backtrace[$i - 1]['function'])
                         && '__toString' === $backtrace[$i]['function']
@@ -594,7 +598,9 @@ class ErrorHandler
         $this->exceptionHandler = null;
         try {
             if (null !== $exceptionHandler) {
-                return \call_user_func($exceptionHandler, $exception);
+                $exceptionHandler($exception);
+
+                return;
             }
             $handlerException = $handlerException ?: $exception;
         } catch (\Exception $handlerException) {

Exception/SilencedErrorContext.php

@@ -54,7 +54,7 @@ class SilencedErrorContext implements \JsonSerializable
         return $this->trace;
     }
 
-    public function JsonSerialize()
+    public function jsonSerialize()
     {
         return [
             'severity' => $this->severity,

FatalErrorHandler/ClassNotFoundFatalErrorHandler.php

@@ -33,11 +33,11 @@ class ClassNotFoundFatalErrorHandler implements FatalErrorHandlerInterface
         $notFoundSuffix = '\' not found';
         $notFoundSuffixLen = \strlen($notFoundSuffix);
         if ($notFoundSuffixLen > $messageLen) {
-            return;
+            return null;
         }
 
         if (0 !== substr_compare($error['message'], $notFoundSuffix, -$notFoundSuffixLen)) {
-            return;
+            return null;
         }
 
         foreach (['class', 'interface', 'trait'] as $typeName) {
@@ -71,6 +71,8 @@ class ClassNotFoundFatalErrorHandler implements FatalErrorHandlerInterface
 
             return new ClassNotFoundException($message, $exception);
         }
+
+        return null;
     }
 
     /**
@@ -185,13 +187,19 @@ class ClassNotFoundFatalErrorHandler implements FatalErrorHandlerInterface
             }
         }
 
-        require_once $file;
+        try {
+            require_once $file;
+        } catch (\Throwable $e) {
+            return null;
+        }
 
         foreach ($candidates as $candidate) {
             if ($this->classExists($candidate)) {
                 return $candidate;
             }
         }
+
+        return null;
     }
 
     /**

FatalErrorHandler/UndefinedFunctionFatalErrorHandler.php

@@ -30,17 +30,17 @@ class UndefinedFunctionFatalErrorHandler implements FatalErrorHandlerInterface
         $notFoundSuffix = '()';
         $notFoundSuffixLen = \strlen($notFoundSuffix);
         if ($notFoundSuffixLen > $messageLen) {
-            return;
+            return null;
         }
 
         if (0 !== substr_compare($error['message'], $notFoundSuffix, -$notFoundSuffixLen)) {
-            return;
+            return null;
         }
 
         $prefix = 'Call to undefined function ';
         $prefixLen = \strlen($prefix);
         if (0 !== strpos($error['message'], $prefix)) {
-            return;
+            return null;
         }
 
         $fullyQualifiedFunctionName = substr($error['message'], $prefixLen, -$notFoundSuffixLen);

FatalErrorHandler/UndefinedMethodFatalErrorHandler.php

@@ -28,7 +28,7 @@ class UndefinedMethodFatalErrorHandler implements FatalErrorHandlerInterface
     {
         preg_match('/^Call to undefined method (.*)::(.*)\(\)$/', $error['message'], $matches);
         if (!$matches) {
-            return;
+            return null;
         }
 
         $className = $matches[1];

LICENSE

@@ -1,4 +1,4 @@
-Copyright (c) 2004-2019 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

@@ -6,7 +6,7 @@ The Debug component provides tools to ease debugging PHP code.
 Resources
 ---------
 
-  * [Documentation](https://symfony.com/doc/current/components/debug/index.html)
+  * [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)

Tests/DebugClassLoaderTest.php

@@ -59,21 +59,19 @@ class DebugClassLoaderTest extends TestCase
         $this->fail('DebugClassLoader did not register');
     }
 
-    /**
-     * @expectedException \Exception
-     * @expectedExceptionMessage boo
-     */
     public function testThrowingClass()
     {
+        $this->expectException('Exception');
+        $this->expectExceptionMessage('boo');
         try {
-            class_exists(__NAMESPACE__.'\Fixtures\Throwing');
+            class_exists(Fixtures\Throwing::class);
             $this->fail('Exception expected');
         } catch (\Exception $e) {
             $this->assertSame('boo', $e->getMessage());
         }
 
         // the second call also should throw
-        class_exists(__NAMESPACE__.'\Fixtures\Throwing');
+        class_exists(Fixtures\Throwing::class);
     }
 
     public function testUnsilencing()
@@ -92,7 +90,7 @@ class DebugClassLoaderTest extends TestCase
 
         // See below: this will fail with parse error
         // but this should not be @-silenced.
-        @class_exists(__NAMESPACE__.'\TestingUnsilencing', true);
+        @class_exists(TestingUnsilencing::class, true);
 
         $output = ob_get_clean();
 
@@ -139,34 +137,28 @@ class DebugClassLoaderTest extends TestCase
         }
     }
 
-    /**
-     * @expectedException \RuntimeException
-     * @expectedExceptionMessage Case mismatch between loaded and declared class names
-     */
     public function testNameCaseMismatch()
     {
-        class_exists(__NAMESPACE__.'\TestingCaseMismatch', true);
+        $this->expectException('RuntimeException');
+        $this->expectExceptionMessage('Case mismatch between loaded and declared class names');
+        class_exists(TestingCaseMismatch::class, true);
     }
 
-    /**
-     * @expectedException \RuntimeException
-     * @expectedExceptionMessage Case mismatch between class and real file names
-     */
     public function testFileCaseMismatch()
     {
+        $this->expectException('RuntimeException');
+        $this->expectExceptionMessage('Case mismatch between class and real file names');
         if (!file_exists(__DIR__.'/Fixtures/CaseMismatch.php')) {
             $this->markTestSkipped('Can only be run on case insensitive filesystems');
         }
 
-        class_exists(__NAMESPACE__.'\Fixtures\CaseMismatch', true);
+        class_exists(Fixtures\CaseMismatch::class, true);
     }
 
-    /**
-     * @expectedException \RuntimeException
-     * @expectedExceptionMessage Case mismatch between loaded and declared class names
-     */
     public function testPsr4CaseMismatch()
     {
+        $this->expectException('RuntimeException');
+        $this->expectExceptionMessage('Case mismatch between loaded and declared class names');
         class_exists(__NAMESPACE__.'\Fixtures\Psr4CaseMismatch', true);
     }
 
@@ -182,7 +174,7 @@ class DebugClassLoaderTest extends TestCase
 
     public function testClassAlias()
     {
-        $this->assertTrue(class_exists(__NAMESPACE__.'\Fixtures\ClassAlias', true));
+        $this->assertTrue(class_exists(Fixtures\ClassAlias::class, true));
     }
 
     /**
@@ -224,7 +216,7 @@ class DebugClassLoaderTest extends TestCase
         $e = error_reporting(0);
         trigger_error('', E_USER_NOTICE);
 
-        class_exists('Test\\'.__NAMESPACE__.'\\NonDeprecatedInterfaceClass', true);
+        class_exists('Test\\'.NonDeprecatedInterfaceClass::class, true);
 
         error_reporting($e);
         restore_error_handler();
@@ -272,7 +264,7 @@ class DebugClassLoaderTest extends TestCase
         $e = error_reporting(0);
         trigger_error('', E_USER_NOTICE);
 
-        class_exists('Test\\'.__NAMESPACE__.'\\Float', true);
+        class_exists('Test\\'.Float::class, true);
 
         error_reporting($e);
         restore_error_handler();
@@ -297,7 +289,7 @@ class DebugClassLoaderTest extends TestCase
         require __DIR__.'/Fixtures/FinalClasses.php';
 
         $i = 1;
-        while (class_exists($finalClass = __NAMESPACE__.'\\Fixtures\\FinalClass'.$i++, false)) {
+        while (class_exists($finalClass = Fixtures\FinalClass::class.$i++, false)) {
             spl_autoload_call($finalClass);
             class_exists('Test\\'.__NAMESPACE__.'\\Extends'.substr($finalClass, strrpos($finalClass, '\\') + 1), true);
         }
@@ -323,7 +315,7 @@ class DebugClassLoaderTest extends TestCase
         set_error_handler(function ($type, $msg) use (&$deprecations) { $deprecations[] = $msg; });
         $e = error_reporting(E_USER_DEPRECATED);
 
-        class_exists(__NAMESPACE__.'\\Fixtures\\ExtendedFinalMethod', true);
+        class_exists(Fixtures\ExtendedFinalMethod::class, true);
 
         error_reporting($e);
         restore_error_handler();
@@ -342,7 +334,7 @@ class DebugClassLoaderTest extends TestCase
         $e = error_reporting(0);
         trigger_error('', E_USER_NOTICE);
 
-        class_exists('Test\\'.__NAMESPACE__.'\\ExtendsAnnotatedClass', true);
+        class_exists('Test\\'.ExtendsAnnotatedClass::class, true);
 
         error_reporting($e);
         restore_error_handler();
@@ -359,7 +351,7 @@ class DebugClassLoaderTest extends TestCase
         set_error_handler(function ($type, $msg) use (&$deprecations) { $deprecations[] = $msg; });
         $e = error_reporting(E_USER_DEPRECATED);
 
-        class_exists('Test\\'.__NAMESPACE__.'\\ExtendsInternals', true);
+        class_exists('Test\\'.ExtendsInternals::class, true);
 
         error_reporting($e);
         restore_error_handler();
@@ -378,7 +370,7 @@ class DebugClassLoaderTest extends TestCase
         set_error_handler(function ($type, $msg) use (&$deprecations) { $deprecations[] = $msg; });
         $e = error_reporting(E_USER_DEPRECATED);
 
-        class_exists('Test\\'.__NAMESPACE__.'\\UseTraitWithInternalMethod', true);
+        class_exists('Test\\'.UseTraitWithInternalMethod::class, true);
 
         error_reporting($e);
         restore_error_handler();
@@ -388,7 +380,7 @@ class DebugClassLoaderTest extends TestCase
 
     public function testEvaluatedCode()
     {
-        $this->assertTrue(class_exists(__NAMESPACE__.'\Fixtures\DefinitionInEvaluatedCode', true));
+        $this->assertTrue(class_exists(Fixtures\DefinitionInEvaluatedCode::class, true));
     }
 }
 
@@ -407,11 +399,11 @@ class ClassLoader
     {
         $fixtureDir = __DIR__.\DIRECTORY_SEPARATOR.'Fixtures'.\DIRECTORY_SEPARATOR;
 
-        if (__NAMESPACE__.'\TestingUnsilencing' === $class) {
+        if (TestingUnsilencing::class === $class) {
             eval('-- parse error --');
-        } elseif (__NAMESPACE__.'\TestingStacking' === $class) {
+        } elseif (TestingStacking::class === $class) {
             eval('namespace '.__NAMESPACE__.'; class TestingStacking { function foo() {} }');
-        } elseif (__NAMESPACE__.'\TestingCaseMismatch' === $class) {
+        } elseif (TestingCaseMismatch::class === $class) {
             eval('namespace '.__NAMESPACE__.'; class TestingCaseMisMatch {}');
         } elseif (__NAMESPACE__.'\Fixtures\Psr4CaseMismatch' === $class) {
             return $fixtureDir.'psr4'.\DIRECTORY_SEPARATOR.'Psr4CaseMismatch.php';
@@ -421,31 +413,33 @@ class ClassLoader
             return $fixtureDir.'notPsr0Bis.php';
         } elseif ('Symfony\Bridge\Debug\Tests\Fixtures\ExtendsDeprecatedParent' === $class) {
             eval('namespace Symfony\Bridge\Debug\Tests\Fixtures; class ExtendsDeprecatedParent extends \\'.__NAMESPACE__.'\Fixtures\DeprecatedClass {}');
-        } elseif ('Test\\'.__NAMESPACE__.'\DeprecatedParentClass' === $class) {
+        } elseif ('Test\\'.DeprecatedParentClass::class === $class) {
             eval('namespace Test\\'.__NAMESPACE__.'; class DeprecatedParentClass extends \\'.__NAMESPACE__.'\Fixtures\DeprecatedClass {}');
-        } elseif ('Test\\'.__NAMESPACE__.'\DeprecatedInterfaceClass' === $class) {
+        } elseif ('Test\\'.DeprecatedInterfaceClass::class === $class) {
             eval('namespace Test\\'.__NAMESPACE__.'; class DeprecatedInterfaceClass implements \\'.__NAMESPACE__.'\Fixtures\DeprecatedInterface {}');
-        } elseif ('Test\\'.__NAMESPACE__.'\NonDeprecatedInterfaceClass' === $class) {
+        } elseif ('Test\\'.NonDeprecatedInterfaceClass::class === $class) {
             eval('namespace Test\\'.__NAMESPACE__.'; class NonDeprecatedInterfaceClass implements \\'.__NAMESPACE__.'\Fixtures\NonDeprecatedInterface {}');
-        } elseif ('Test\\'.__NAMESPACE__.'\Float' === $class) {
+        } elseif ('Test\\'.Float::class === $class) {
             eval('namespace Test\\'.__NAMESPACE__.'; class Float {}');
-        } elseif (0 === strpos($class, 'Test\\'.__NAMESPACE__.'\ExtendsFinalClass')) {
+        } elseif (0 === strpos($class, 'Test\\'.ExtendsFinalClass::class)) {
             $classShortName = substr($class, strrpos($class, '\\') + 1);
             eval('namespace Test\\'.__NAMESPACE__.'; class '.$classShortName.' extends \\'.__NAMESPACE__.'\Fixtures\\'.substr($classShortName, 7).' {}');
-        } elseif ('Test\\'.__NAMESPACE__.'\ExtendsAnnotatedClass' === $class) {
+        } elseif ('Test\\'.ExtendsAnnotatedClass::class === $class) {
             eval('namespace Test\\'.__NAMESPACE__.'; class ExtendsAnnotatedClass extends \\'.__NAMESPACE__.'\Fixtures\AnnotatedClass {
                 public function deprecatedMethod() { }
             }');
-        } elseif ('Test\\'.__NAMESPACE__.'\ExtendsInternals' === $class) {
+        } elseif ('Test\\'.ExtendsInternals::class === $class) {
             eval('namespace Test\\'.__NAMESPACE__.'; class ExtendsInternals extends ExtendsInternalsParent {
                 use \\'.__NAMESPACE__.'\Fixtures\InternalTrait;
 
                 public function internalMethod() { }
             }');
-        } elseif ('Test\\'.__NAMESPACE__.'\ExtendsInternalsParent' === $class) {
+        } elseif ('Test\\'.ExtendsInternalsParent::class === $class) {
             eval('namespace Test\\'.__NAMESPACE__.'; class ExtendsInternalsParent extends \\'.__NAMESPACE__.'\Fixtures\InternalClass implements \\'.__NAMESPACE__.'\Fixtures\InternalInterface { }');
-        } elseif ('Test\\'.__NAMESPACE__.'\UseTraitWithInternalMethod' === $class) {
+        } elseif ('Test\\'.UseTraitWithInternalMethod::class === $class) {
             eval('namespace Test\\'.__NAMESPACE__.'; class UseTraitWithInternalMethod { use \\'.__NAMESPACE__.'\Fixtures\TraitWithInternalMethod; }');
         }
+
+        return null;
     }
 }

Tests/ErrorHandlerTest.php

@@ -70,8 +70,8 @@ class ErrorHandlerTest extends TestCase
 
     public function testErrorGetLast()
     {
-        $handler = ErrorHandler::register();
         $logger = $this->getMockBuilder('Psr\Log\LoggerInterface')->getMock();
+        $handler = ErrorHandler::register();
         $handler->setDefaultLogger($logger);
         $handler->screamAt(E_ALL);
 
@@ -143,9 +143,8 @@ class ErrorHandlerTest extends TestCase
     public function testDefaultLogger()
     {
         try {
-            $handler = ErrorHandler::register();
-
             $logger = $this->getMockBuilder('Psr\Log\LoggerInterface')->getMock();
+            $handler = ErrorHandler::register();
 
             $handler->setDefaultLogger($logger, E_NOTICE);
             $handler->setDefaultLogger($logger, [E_USER_NOTICE => LogLevel::CRITICAL]);
@@ -234,7 +233,7 @@ class ErrorHandlerTest extends TestCase
             $logger
                 ->expects($this->once())
                 ->method('log')
-                ->will($this->returnCallback($warnArgCheck))
+                ->willReturnCallback($warnArgCheck)
             ;
 
             $handler = ErrorHandler::register();
@@ -262,7 +261,7 @@ class ErrorHandlerTest extends TestCase
             $logger
                 ->expects($this->once())
                 ->method('log')
-                ->will($this->returnCallback($logArgCheck))
+                ->willReturnCallback($logArgCheck)
             ;
 
             $handler = ErrorHandler::register();
@@ -284,6 +283,10 @@ class ErrorHandlerTest extends TestCase
 
     public function testHandleUserError()
     {
+        if (\PHP_VERSION_ID >= 70400) {
+            $this->markTestSkipped('PHP 7.4 allows __toString to throw exceptions');
+        }
+
         try {
             $handler = ErrorHandler::register();
             $handler->throwAt(0, true);
@@ -318,7 +321,7 @@ class ErrorHandlerTest extends TestCase
         $logger
             ->expects($this->once())
             ->method('log')
-            ->will($this->returnCallback($logArgCheck))
+            ->willReturnCallback($logArgCheck)
         ;
 
         $handler = new ErrorHandler();
@@ -334,12 +337,11 @@ class ErrorHandlerTest extends TestCase
     public function testHandleException()
     {
         try {
+            $logger = $this->getMockBuilder('Psr\Log\LoggerInterface')->getMock();
             $handler = ErrorHandler::register();
 
             $exception = new \Exception('foo');
 
-            $logger = $this->getMockBuilder('Psr\Log\LoggerInterface')->getMock();
-
             $logArgCheck = function ($level, $message, $context) {
                 $this->assertSame('Uncaught Exception: foo', $message);
                 $this->assertArrayHasKey('exception', $context);
@@ -349,7 +351,7 @@ class ErrorHandlerTest extends TestCase
             $logger
                 ->expects($this->exactly(2))
                 ->method('log')
-                ->will($this->returnCallback($logArgCheck))
+                ->willReturnCallback($logArgCheck)
             ;
 
             $handler->setDefaultLogger($logger, E_ERROR);
@@ -483,6 +485,7 @@ class ErrorHandlerTest extends TestCase
     public function testHandleFatalError()
     {
         try {
+            $logger = $this->getMockBuilder('Psr\Log\LoggerInterface')->getMock();
             $handler = ErrorHandler::register();
 
             $error = [
@@ -492,8 +495,6 @@ class ErrorHandlerTest extends TestCase
                 'line' => 123,
             ];
 
-            $logger = $this->getMockBuilder('Psr\Log\LoggerInterface')->getMock();
-
             $logArgCheck = function ($level, $message, $context) {
                 $this->assertEquals('Fatal Parse Error: foo', $message);
                 $this->assertArrayHasKey('exception', $context);
@@ -503,7 +504,7 @@ class ErrorHandlerTest extends TestCase
             $logger
                 ->expects($this->once())
                 ->method('log')
-                ->will($this->returnCallback($logArgCheck))
+                ->willReturnCallback($logArgCheck)
             ;
 
             $handler->setDefaultLogger($logger, E_PARSE);
@@ -576,11 +577,11 @@ class ErrorHandlerTest extends TestCase
     }
 
     /**
-     * @expectedException \Exception
      * @group no-hhvm
      */
     public function testCustomExceptionHandler()
     {
+        $this->expectException('Exception');
         $handler = new ErrorHandler();
         $handler->setExceptionHandler(function ($e) use ($handler) {
             $handler->handleException($e);

Tests/Exception/FlattenExceptionTest.php

@@ -199,6 +199,10 @@ class FlattenExceptionTest extends TestCase
 
     public function testArguments()
     {
+        if (\PHP_VERSION_ID >= 70400) {
+            $this->markTestSkipped('PHP 7.4 removes arguments from exception traces.');
+        }
+
         $dh = opendir(__DIR__);
         $fh = tmpfile();
 
@@ -256,22 +260,30 @@ class FlattenExceptionTest extends TestCase
 
         // assertEquals() does not like NAN values.
         $this->assertEquals($array[$i][0], 'float');
-        $this->assertTrue(is_nan($array[$i++][1]));
+        $this->assertNan($array[$i][1]);
     }
 
     public function testRecursionInArguments()
     {
+        if (\PHP_VERSION_ID >= 70400) {
+            $this->markTestSkipped('PHP 7.4 removes arguments from exception traces.');
+        }
+
         $a = null;
         $a = ['foo', [2, &$a]];
         $exception = $this->createException($a);
 
         $flattened = FlattenException::create($exception);
         $trace = $flattened->getTrace();
-        $this->assertContains('*DEEP NESTED ARRAY*', serialize($trace));
+        $this->assertStringContainsString('*DEEP NESTED ARRAY*', serialize($trace));
     }
 
     public function testTooBigArray()
     {
+        if (\PHP_VERSION_ID >= 70400) {
+            $this->markTestSkipped('PHP 7.4 removes arguments from exception traces.');
+        }
+
         $a = [];
         for ($i = 0; $i < 20; ++$i) {
             for ($j = 0; $j < 50; ++$j) {
@@ -291,8 +303,8 @@ class FlattenExceptionTest extends TestCase
 
         $serializeTrace = serialize($trace);
 
-        $this->assertContains('*SKIPPED over 10000 entries*', $serializeTrace);
-        $this->assertNotContains('*value1*', $serializeTrace);
+        $this->assertStringContainsString('*SKIPPED over 10000 entries*', $serializeTrace);
+        $this->assertStringNotContainsString('*value1*', $serializeTrace);
     }
 
     private function createException($foo)

Tests/ExceptionHandlerTest.php

@@ -39,8 +39,8 @@ class ExceptionHandlerTest extends TestCase
         $handler->sendPhpResponse(new \RuntimeException('Foo'));
         $response = ob_get_clean();
 
-        $this->assertContains('Whoops, looks like something went wrong.', $response);
-        $this->assertNotContains('<div class="trace trace-as-html">', $response);
+        $this->assertStringContainsString('Whoops, looks like something went wrong.', $response);
+        $this->assertStringNotContainsString('<div class="trace trace-as-html">', $response);
 
         $handler = new ExceptionHandler(true);
 
@@ -48,8 +48,8 @@ class ExceptionHandlerTest extends TestCase
         $handler->sendPhpResponse(new \RuntimeException('Foo'));
         $response = ob_get_clean();
 
-        $this->assertContains('Whoops, looks like something went wrong.', $response);
-        $this->assertContains('<div class="trace trace-as-html">', $response);
+        $this->assertStringContainsString('Whoops, looks like something went wrong.', $response);
+        $this->assertStringContainsString('<div class="trace trace-as-html">', $response);
     }
 
     public function testStatusCode()
@@ -60,7 +60,7 @@ class ExceptionHandlerTest extends TestCase
         $handler->sendPhpResponse(new NotFoundHttpException('Foo'));
         $response = ob_get_clean();
 
-        $this->assertContains('Sorry, the page you are looking for could not be found.', $response);
+        $this->assertStringContainsString('Sorry, the page you are looking for could not be found.', $response);
 
         $expectedHeaders = [
             ['HTTP/1.0 404', true, null],
@@ -76,7 +76,7 @@ class ExceptionHandlerTest extends TestCase
 
         ob_start();
         $handler->sendPhpResponse(new MethodNotAllowedHttpException(['POST']));
-        $response = ob_get_clean();
+        ob_get_clean();
 
         $expectedHeaders = [
             ['HTTP/1.0 405', true, null],
@@ -99,35 +99,65 @@ class ExceptionHandlerTest extends TestCase
 
     public function testHandle()
     {
-        $exception = new \Exception('foo');
+        $handler = new ExceptionHandler(true);
+        ob_start();
 
-        $handler = $this->getMockBuilder('Symfony\Component\Debug\ExceptionHandler')->setMethods(['sendPhpResponse'])->getMock();
-        $handler
-            ->expects($this->exactly(2))
-            ->method('sendPhpResponse');
+        $handler->handle(new \Exception('foo'));
 
-        $handler->handle($exception);
+        $this->assertThatTheExceptionWasOutput(ob_get_clean(), \Exception::class, 'Exception', 'foo');
+    }
 
-        $handler->setHandler(function ($e) use ($exception) {
-            $this->assertSame($exception, $e);
+    public function testHandleWithACustomHandlerThatOutputsSomething()
+    {
+        $handler = new ExceptionHandler(true);
+        ob_start();
+        $handler->setHandler(function () {
+            echo 'ccc';
         });
 
-        $handler->handle($exception);
+        $handler->handle(new \Exception());
+        ob_end_flush(); // Necessary because of this PHP bug : https://bugs.php.net/76563
+        $this->assertSame('ccc', ob_get_clean());
+    }
+
+    public function testHandleWithACustomHandlerThatOutputsNothing()
+    {
+        $handler = new ExceptionHandler(true);
+        $handler->setHandler(function () {});
+
+        $handler->handle(new \Exception('ccc'));
+
+        $this->assertThatTheExceptionWasOutput(ob_get_clean(), \Exception::class, 'Exception', 'ccc');
+    }
+
+    public function testHandleWithACustomHandlerThatFails()
+    {
+        $handler = new ExceptionHandler(true);
+        $handler->setHandler(function () {
+            throw new \RuntimeException();
+        });
+
+        $handler->handle(new \Exception('ccc'));
+
+        $this->assertThatTheExceptionWasOutput(ob_get_clean(), \Exception::class, 'Exception', 'ccc');
     }
 
     public function testHandleOutOfMemoryException()
     {
-        $exception = new OutOfMemoryException('foo', 0, E_ERROR, __FILE__, __LINE__);
-
-        $handler = $this->getMockBuilder('Symfony\Component\Debug\ExceptionHandler')->setMethods(['sendPhpResponse'])->getMock();
-        $handler
-            ->expects($this->once())
-            ->method('sendPhpResponse');
-
-        $handler->setHandler(function ($e) {
+        $handler = new ExceptionHandler(true);
+        ob_start();
+        $handler->setHandler(function () {
             $this->fail('OutOfMemoryException should bypass the handler');
         });
 
-        $handler->handle($exception);
+        $handler->handle(new OutOfMemoryException('foo', 0, E_ERROR, __FILE__, __LINE__));
+
+        $this->assertThatTheExceptionWasOutput(ob_get_clean(), OutOfMemoryException::class, 'OutOfMemoryException', 'foo');
+    }
+
+    private function assertThatTheExceptionWasOutput($content, $expectedClass, $expectedTitle, $expectedMessage)
+    {
+        $this->assertStringContainsString(sprintf('<span class="exception_title"><abbr title="%s">%s</abbr></span>', $expectedClass, $expectedTitle), $content);
+        $this->assertStringContainsString(sprintf('<p class="break-long-words trace-message">%s</p>', $expectedMessage), $content);
     }
 }

Tests/FatalErrorHandler/ClassNotFoundFatalErrorHandlerTest.php

@@ -29,6 +29,10 @@ class ClassNotFoundFatalErrorHandlerTest extends TestCase
             // 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) {
@@ -61,7 +65,7 @@ class ClassNotFoundFatalErrorHandlerTest extends TestCase
         }
 
         $this->assertInstanceOf('Symfony\Component\Debug\Exception\ClassNotFoundException', $exception);
-        $this->assertSame($translatedMessage, $exception->getMessage());
+        $this->assertRegExp($translatedMessage, $exception->getMessage());
         $this->assertSame($error['type'], $exception->getSeverity());
         $this->assertSame($error['file'], $exception->getFile());
         $this->assertSame($error['line'], $exception->getLine());
@@ -71,6 +75,7 @@ class ClassNotFoundFatalErrorHandlerTest extends TestCase
     {
         $autoloader = new ComposerClassLoader();
         $autoloader->add('Symfony\Component\Debug\Exception\\', realpath(__DIR__.'/../../Exception'));
+        $autoloader->add('Symfony_Component_Debug_Tests_Fixtures', realpath(__DIR__.'/../../Tests/Fixtures'));
 
         $debugClassLoader = new DebugClassLoader([$autoloader, 'loadClass']);
 
@@ -82,7 +87,7 @@ class ClassNotFoundFatalErrorHandlerTest extends TestCase
                     'file' => 'foo.php',
                     'message' => 'Class \'WhizBangFactory\' not found',
                 ],
-                "Attempted to load class \"WhizBangFactory\" from the global namespace.\nDid you forget a \"use\" statement?",
+                "/^Attempted to load class \"WhizBangFactory\" from the global namespace.\nDid you forget a \"use\" statement\?$/",
             ],
             [
                 [
@@ -91,7 +96,7 @@ class ClassNotFoundFatalErrorHandlerTest extends TestCase
                     'file' => 'foo.php',
                     'message' => 'Class \'Foo\\Bar\\WhizBangFactory\' not found',
                 ],
-                "Attempted to load class \"WhizBangFactory\" from namespace \"Foo\\Bar\".\nDid you forget a \"use\" statement for another namespace?",
+                "/^Attempted to load class \"WhizBangFactory\" from namespace \"Foo\\\\Bar\".\nDid you forget a \"use\" statement for another namespace\?$/",
             ],
             [
                 [
@@ -100,7 +105,8 @@ class ClassNotFoundFatalErrorHandlerTest extends TestCase
                     '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\"?",
+                "/^Attempted to load class \"UndefinedFunctionException\" from the global namespace.\nDid you forget a \"use\" statement for .*\"Symfony\\\\Component\\\\Debug\\\\Exception\\\\UndefinedFunctionException\"\?$/",
+                [$debugClassLoader, 'loadClass'],
             ],
             [
                 [
@@ -109,35 +115,7 @@ class ClassNotFoundFatalErrorHandlerTest extends TestCase
                     '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\"?",
-            ],
-            [
-                [
-                    '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\"?",
-            ],
-            [
-                [
-                    '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\"?",
-                [$autoloader, 'loadClass'],
-            ],
-            [
-                [
-                    'type' => 1,
-                    'line' => 12,
-                    'file' => 'foo.php',
-                    'message' => 'Class \'Foo\\Bar\\UndefinedFunctionException\' not found',
-                ],
-                "Attempted to load class \"UndefinedFunctionException\" from namespace \"Foo\Bar\".\nDid you forget a \"use\" statement for \"Symfony\Component\Debug\Exception\UndefinedFunctionException\"?",
+                "/^Attempted to load class \"PEARClass\" from the global namespace.\nDid you forget a \"use\" statement for \"Symfony_Component_Debug_Tests_Fixtures_PEARClass\"\?$/",
                 [$debugClassLoader, 'loadClass'],
             ],
             [
@@ -147,7 +125,37 @@ class ClassNotFoundFatalErrorHandlerTest extends TestCase
                     'file' => 'foo.php',
                     'message' => 'Class \'Foo\\Bar\\UndefinedFunctionException\' not found',
                 ],
-                "Attempted to load class \"UndefinedFunctionException\" from namespace \"Foo\\Bar\".\nDid you forget a \"use\" statement for another namespace?",
+                "/^Attempted to load class \"UndefinedFunctionException\" from namespace \"Foo\\\\Bar\".\nDid you forget a \"use\" statement for .*\"Symfony\\\\Component\\\\Debug\\\\Exception\\\\UndefinedFunctionException\"\?$/",
+                [$debugClassLoader, 'loadClass'],
+            ],
+            [
+                [
+                    'type' => 1,
+                    'line' => 12,
+                    'file' => 'foo.php',
+                    'message' => 'Class \'Foo\\Bar\\UndefinedFunctionException\' not found',
+                ],
+                "/^Attempted to load class \"UndefinedFunctionException\" from namespace \"Foo\\\\Bar\".\nDid you forget a \"use\" statement for \"Symfony\\\\Component\\\\Debug\\\\Exception\\\\UndefinedFunctionException\"\?$/",
+                [$autoloader, 'loadClass'],
+            ],
+            [
+                [
+                    'type' => 1,
+                    'line' => 12,
+                    'file' => 'foo.php',
+                    'message' => 'Class \'Foo\\Bar\\UndefinedFunctionException\' not found',
+                ],
+                "/^Attempted to load class \"UndefinedFunctionException\" from namespace \"Foo\\\\Bar\".\nDid you forget a \"use\" statement for \"Symfony\\\\Component\\\\Debug\\\\Exception\\\\UndefinedFunctionException\"\?/",
+                [$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 */ },
             ],
         ];

Tests/MockExceptionHandler.php

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