Merge branch '3.4' into 4.0

* 3.4:
  [HttpFoundation] Add Session::isEmpty(), fix MockFileSessionStorage to behave like the native one
  [HttpKernel] Add a better error messages when passing a private or non-tagged controller
  [VarDumper] Dont use empty(), it chokes on eg GMP objects
  [Dotenv] Changed preg_match flags from null to 0
  remove upgrade instructions for kernel.root_dir
  [HttpKernel] Arrays with scalar values passed to ESI fragment renderer throw deprecation notice
  [HttpKernel] add a test for FilterControllerEvents

UPGRADE-4.0.md

@@ -598,12 +598,6 @@ HttpKernel
            tags: ['console.command']
    ```
 
- * Removed the `kernel.root_dir` parameter. Use the `kernel.project_dir` parameter
-   instead.
-
- * Removed the `Kernel::getRootDir()` method. Use the `Kernel::getProjectDir()`
-   method instead.
-
  * The `Extension::addClassesToCompile()` and `Extension::getClassesToCompile()` methods have been removed.
 
  * Possibility to pass non-scalar values as URI attributes to the ESI and SSI

src/Symfony/Bundle/SecurityBundle/DependencyInjection/Security/Factory/AbstractFactory.php

@@ -29,7 +29,7 @@ abstract class AbstractFactory implements SecurityFactoryInterface
     protected $options = array(
         'check_path' => '/login_check',
         'use_forward' => false,
-        'require_previous_session' => true,
+        'require_previous_session' => false,
     );
 
     protected $defaultSuccessHandlerOptions = array(

src/Symfony/Bundle/SecurityBundle/DependencyInjection/Security/Factory/JsonLoginFactory.php

@@ -28,7 +28,6 @@ class JsonLoginFactory extends AbstractFactory
         $this->addOption('password_path', 'password');
         $this->defaultFailureHandlerOptions = array();
         $this->defaultSuccessHandlerOptions = array();
-        $this->options['require_previous_session'] = false;
     }
 
     /**

src/Symfony/Component/Dotenv/Dotenv.php

@@ -174,7 +174,7 @@ final class Dotenv
 
     private function lexValue()
     {
-        if (preg_match('/[ \t]*+(?:#.*)?$/Am', $this->data, $matches, null, $this->cursor)) {
+        if (preg_match('/[ \t]*+(?:#.*)?$/Am', $this->data, $matches, 0, $this->cursor)) {
             $this->moveCursor($matches[0]);
             $this->skipEmptyLines();
 
@@ -296,7 +296,7 @@ final class Dotenv
 
     private function skipEmptyLines()
     {
-        if (preg_match('/(?:\s*+(?:#[^\n]*+)?+)++/A', $this->data, $match, null, $this->cursor)) {
+        if (preg_match('/(?:\s*+(?:#[^\n]*+)?+)++/A', $this->data, $match, 0, $this->cursor)) {
             $this->moveCursor($match[0]);
         }
     }

src/Symfony/Component/HttpFoundation/Session/Session.php

@@ -28,6 +28,7 @@ class Session implements SessionInterface, \IteratorAggregate, \Countable
 
     private $flashName;
     private $attributeName;
+    private $data = array();
 
     /**
      * @param SessionStorageInterface $storage    A SessionStorageInterface instance
@@ -108,7 +109,7 @@ class Session implements SessionInterface, \IteratorAggregate, \Countable
      */
     public function clear()
     {
-        $this->storage->getBag($this->attributeName)->clear();
+        $this->getAttributeBag()->clear();
     }
 
     /**
@@ -139,6 +140,22 @@ class Session implements SessionInterface, \IteratorAggregate, \Countable
         return count($this->getAttributeBag()->all());
     }
 
+    /**
+     * @return bool
+     *
+     * @internal
+     */
+    public function isEmpty()
+    {
+        foreach ($this->data as &$data) {
+            if (!empty($data)) {
+                return false;
+            }
+        }
+
+        return true;
+    }
+
     /**
      * {@inheritdoc}
      */
@@ -210,7 +227,7 @@ class Session implements SessionInterface, \IteratorAggregate, \Countable
      */
     public function registerBag(SessionBagInterface $bag)
     {
-        $this->storage->registerBag($bag);
+        $this->storage->registerBag(new SessionBagProxy($bag, $this->data));
     }
 
     /**
@@ -218,7 +235,7 @@ class Session implements SessionInterface, \IteratorAggregate, \Countable
      */
     public function getBag($name)
     {
-        return $this->storage->getBag($name);
+        return $this->storage->getBag($name)->getBag();
     }
 
     /**
@@ -240,6 +257,6 @@ class Session implements SessionInterface, \IteratorAggregate, \Countable
      */
     private function getAttributeBag()
     {
-        return $this->storage->getBag($this->attributeName);
+        return $this->storage->getBag($this->attributeName)->getBag();
     }
 }

src/Symfony/Component/HttpFoundation/Session/SessionBagProxy.php

@@ -0,0 +1,79 @@
+<?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\HttpFoundation\Session;
+
+/**
+ * @author Nicolas Grekas <p@tchwork.com>
+ *
+ * @internal
+ */
+final class SessionBagProxy implements SessionBagInterface
+{
+    private $bag;
+    private $data;
+
+    public function __construct(SessionBagInterface $bag, array &$data)
+    {
+        $this->bag = $bag;
+        $this->data = &$data;
+    }
+
+    /**
+     * @return SessionBagInterface
+     */
+    public function getBag()
+    {
+        return $this->bag;
+    }
+
+    /**
+     * @return bool
+     */
+    public function isEmpty()
+    {
+        return empty($this->data[$this->bag->getStorageKey()]);
+    }
+
+    /**
+     * {@inheritdoc}
+     */
+    public function getName()
+    {
+        return $this->bag->getName();
+    }
+
+    /**
+     * {@inheritdoc}
+     */
+    public function initialize(array &$array)
+    {
+        $this->data[$this->bag->getStorageKey()] = &$array;
+
+        $this->bag->initialize($array);
+    }
+
+    /**
+     * {@inheritdoc}
+     */
+    public function getStorageKey()
+    {
+        return $this->bag->getStorageKey();
+    }
+
+    /**
+     * {@inheritdoc}
+     */
+    public function clear()
+    {
+        return $this->bag->clear();
+    }
+}

src/Symfony/Component/HttpFoundation/Session/Storage/MockFileSessionStorage.php

@@ -91,7 +91,26 @@ class MockFileSessionStorage extends MockArraySessionStorage
             throw new \RuntimeException('Trying to save a session that was not started yet or was already closed');
         }
 
-        file_put_contents($this->getFilePath(), serialize($this->data));
+        $data = $this->data;
+
+        foreach ($this->bags as $bag) {
+            if (empty($data[$key = $bag->getStorageKey()])) {
+                unset($data[$key]);
+            }
+        }
+        if (array($key = $this->metadataBag->getStorageKey()) === array_keys($data)) {
+            unset($data[$key]);
+        }
+
+        try {
+            if ($data) {
+                file_put_contents($this->getFilePath(), serialize($data));
+            } else {
+                $this->destroy();
+            }
+        } finally {
+            $this->data = $data;
+        }
 
         // this is needed for Silex, where the session object is re-used across requests
         // in functional tests. In Symfony, the container is rebooted, so we don't have

src/Symfony/Component/HttpFoundation/Tests/Session/SessionTest.php

@@ -221,4 +221,22 @@ class SessionTest extends TestCase
     {
         $this->assertInstanceOf('Symfony\Component\HttpFoundation\Session\Storage\MetadataBag', $this->session->getMetadataBag());
     }
+
+    public function testIsEmpty()
+    {
+        $this->assertTrue($this->session->isEmpty());
+
+        $this->session->set('hello', 'world');
+        $this->assertFalse($this->session->isEmpty());
+
+        $this->session->remove('hello');
+        $this->assertTrue($this->session->isEmpty());
+
+        $flash = $this->session->getFlashBag();
+        $flash->set('hello', 'world');
+        $this->assertFalse($this->session->isEmpty());
+
+        $flash->get('hello');
+        $this->assertTrue($this->session->isEmpty());
+    }
 }

src/Symfony/Component/HttpKernel/Controller/ContainerControllerResolver.php

@@ -13,6 +13,7 @@ namespace Symfony\Component\HttpKernel\Controller;
 
 use Psr\Container\ContainerInterface;
 use Psr\Log\LoggerInterface;
+use Symfony\Component\DependencyInjection\Container;
 use Symfony\Component\HttpFoundation\Request;
 
 /**
@@ -86,6 +87,15 @@ class ContainerControllerResolver extends ControllerResolver
             return $this->container->get($class);
         }
 
-        return parent::instantiateController($class);
+        try {
+            return parent::instantiateController($class);
+        } catch (\ArgumentCountError $e) {
+        }
+
+        if ($this->container instanceof Container && in_array($class, $this->container->getRemovedIds(), true)) {
+            throw new \LogicException(sprintf('Controller "%s" cannot be fetched from the container because it is private. Did you forget to tag the service with "controller.service_arguments"?', $class), 0, $e);
+        }
+
+        throw $e;
     }
 }

src/Symfony/Component/HttpKernel/EventListener/AbstractTestSessionListener.php

@@ -12,6 +12,7 @@
 namespace Symfony\Component\HttpKernel\EventListener;
 
 use Symfony\Component\HttpFoundation\Cookie;
+use Symfony\Component\HttpFoundation\Session\Session;
 use Symfony\Component\HttpFoundation\Session\SessionInterface;
 use Symfony\Component\HttpKernel\KernelEvents;
 use Symfony\Component\HttpKernel\Event\FilterResponseEvent;
@@ -60,8 +61,10 @@ abstract class AbstractTestSessionListener implements EventSubscriberInterface
         $session = $event->getRequest()->getSession();
         if ($session && $session->isStarted()) {
             $session->save();
-            $params = session_get_cookie_params();
-            $event->getResponse()->headers->setCookie(new Cookie($session->getName(), $session->getId(), 0 === $params['lifetime'] ? 0 : time() + $params['lifetime'], $params['path'], $params['domain'], $params['secure'], $params['httponly']));
+            if (!$session instanceof Session || !\method_exists($session, 'isEmpty') || !$session->isEmpty()) {
+                $params = session_get_cookie_params();
+                $event->getResponse()->headers->setCookie(new Cookie($session->getName(), $session->getId(), 0 === $params['lifetime'] ? 0 : time() + $params['lifetime'], $params['path'], $params['domain'], $params['secure'], $params['httponly']));
+            }
         }
     }
 

src/Symfony/Component/HttpKernel/Fragment/AbstractSurrogateFragmentRenderer.php

@@ -98,8 +98,8 @@ abstract class AbstractSurrogateFragmentRenderer extends RoutableFragmentRendere
     private function containsNonScalars(array $values): bool
     {
         foreach ($values as $value) {
-            if (is_array($value) && $this->containsNonScalars($value)) {
-                return true;
+            if (is_array($value)) {
+                return $this->containsNonScalars($value);
             } elseif (!is_scalar($value) && null !== $value) {
                 return true;
             }

src/Symfony/Component/HttpKernel/Tests/Controller/ContainerControllerResolverTest.php

@@ -13,6 +13,8 @@ namespace Symfony\Component\HttpKernel\Tests\Controller;
 
 use Psr\Container\ContainerInterface;
 use Psr\Log\LoggerInterface;
+use Symfony\Component\Debug\ErrorHandler;
+use Symfony\Component\DependencyInjection\Container;
 use Symfony\Component\HttpFoundation\Request;
 use Symfony\Component\HttpKernel\Controller\ContainerControllerResolver;
 
@@ -106,6 +108,38 @@ class ContainerControllerResolverTest extends ControllerResolverTest
         $this->assertSame(array(NonInstantiableController::class, 'action'), $controller);
     }
 
+    /**
+     * @expectedException \LogicException
+     * @expectedExceptionMessage Controller "Symfony\Component\HttpKernel\Tests\Controller\ImpossibleConstructController" cannot be fetched from the container because it is private. Did you forget to tag the service with "controller.service_arguments"?
+     */
+    public function testNonConstructController()
+    {
+        $container = $this->getMockBuilder(Container::class)->getMock();
+        $container->expects($this->at(0))
+            ->method('has')
+            ->with(ImpossibleConstructController::class)
+            ->will($this->returnValue(true))
+        ;
+
+        $container->expects($this->at(1))
+            ->method('has')
+            ->with(ImpossibleConstructController::class)
+            ->will($this->returnValue(false))
+        ;
+
+        $container->expects($this->atLeastOnce())
+            ->method('getRemovedIds')
+            ->with()
+            ->will($this->returnValue(array(ImpossibleConstructController::class)))
+        ;
+
+        $resolver = $this->createControllerResolver(null, $container);
+        $request = Request::create('/');
+        $request->attributes->set('_controller', array(ImpossibleConstructController::class, 'action'));
+
+        $resolver->getController($request);
+    }
+
     public function testNonInstantiableControllerWithCorrespondingService()
     {
         $service = new \stdClass();
@@ -196,3 +230,14 @@ abstract class NonInstantiableController
     {
     }
 }
+
+class ImpossibleConstructController
+{
+    public function __construct($toto, $controller)
+    {
+    }
+
+    public function action()
+    {
+    }
+}

src/Symfony/Component/HttpKernel/Tests/Event/FilterControllerArgumentsEventTest.php

@@ -0,0 +1,17 @@
+<?php
+
+namespace Symfony\Component\HttpKernel\Tests\Event;
+
+use Symfony\Component\HttpFoundation\Request;
+use Symfony\Component\HttpKernel\Event\FilterControllerArgumentsEvent;
+use PHPUnit\Framework\TestCase;
+use Symfony\Component\HttpKernel\Tests\TestHttpKernel;
+
+class FilterControllerArgumentsEventTest extends TestCase
+{
+    public function testFilterControllerArgumentsEvent()
+    {
+        $filterController = new FilterControllerArgumentsEvent(new TestHttpKernel(), function () {}, array('test'), new Request(), 1);
+        $this->assertEquals($filterController->getArguments(), array('test'));
+    }
+}

src/Symfony/Component/HttpKernel/Tests/EventListener/TestSessionListenerTest.php

@@ -73,6 +73,19 @@ class TestSessionListenerTest extends TestCase
         $this->assertEquals(0, reset($cookies)->getExpiresTime());
     }
 
+    /**
+     * @requires function \Symfony\Component\HttpFoundation\Session\Session::isEmpty
+     */
+    public function testEmptySessionDoesNotSendCookie()
+    {
+        $this->sessionHasBeenStarted();
+        $this->sessionIsEmpty();
+
+        $response = $this->filterResponse(new Request(), HttpKernelInterface::MASTER_REQUEST);
+
+        $this->assertSame(array(), $response->headers->getCookies());
+    }
+
     public function testUnstartedSessionIsNotSave()
     {
         $this->sessionHasNotBeenStarted();
@@ -130,6 +143,13 @@ class TestSessionListenerTest extends TestCase
             ->will($this->returnValue(false));
     }
 
+    private function sessionIsEmpty()
+    {
+        $this->session->expects($this->once())
+            ->method('isEmpty')
+            ->will($this->returnValue(true));
+    }
+
     private function getSession()
     {
         $mock = $this->getMockBuilder('Symfony\Component\HttpFoundation\Session\Session')

src/Symfony/Component/HttpKernel/Tests/Fragment/EsiFragmentRendererTest.php

@@ -26,6 +26,14 @@ class EsiFragmentRendererTest extends TestCase
         $strategy->render('/', Request::create('/'));
     }
 
+    public function testRenderFallbackWithScalar()
+    {
+        $strategy = new EsiFragmentRenderer(new Esi(), $this->getInlineStrategy(true), new UriSigner('foo'));
+        $request = Request::create('/');
+        $reference = new ControllerReference('main_controller', array('foo' => array(true)), array());
+        $strategy->render($reference, $request);
+    }
+
     public function testRender()
     {
         $strategy = new EsiFragmentRenderer(new Esi(), $this->getInlineStrategy());

src/Symfony/Component/VarDumper/Caster/Caster.php

@@ -113,8 +113,8 @@ class Caster
 
             if (null === $v) {
                 $type |= self::EXCLUDE_NULL & $filter;
-            }
-            if (empty($v)) {
+                $type |= self::EXCLUDE_EMPTY & $filter;
+            } elseif (false === $v || '' === $v || '0' === $v || 0 === $v || 0.0 === $v || array() === $v) {
                 $type |= self::EXCLUDE_EMPTY & $filter;
             }
             if ((self::EXCLUDE_NOT_IMPORTANT & $filter) && !in_array($k, $listedProperties, true)) {

src/Symfony/Component/VarDumper/Cloner/VarCloner.php

@@ -101,13 +101,16 @@ class VarCloner extends AbstractCloner
                 // Create $stub when the original value $v can not be used directly
                 // If $v is a nested structure, put that structure in array $a
                 switch (true) {
-                    case empty($v):
-                    case true === $v:
+                    case null === $v:
+                    case \is_bool($v):
                     case \is_int($v):
                     case \is_float($v):
                         continue 2;
 
                     case \is_string($v):
+                        if ('' === $v) {
+                            continue 2;
+                        }
                         if (!\preg_match('//u', $v)) {
                             $stub = new Stub();
                             $stub->type = Stub::TYPE_STRING;
@@ -131,6 +134,9 @@ class VarCloner extends AbstractCloner
                         break;
 
                     case \is_array($v):
+                        if (!$v) {
+                            continue 2;
+                        }
                         $stub = $arrayStub;
                         $stub->class = Stub::ARRAY_INDEXED;