UPGRADE FROM 3.x to 4.0
=======================
ClassLoader
-----------
* The component has been removed. Use Composer instead.
Console
-------
* Setting unknown style options is not supported anymore and throws an
exception.
* The `QuestionHelper::setInputStream()` method is removed. Use
`StreamableInputInterface::setStream()` or `CommandTester::setInputs()`
instead.
Before:
```php
$input = new ArrayInput();
$questionHelper->setInputStream($stream);
$questionHelper->ask($input, $output, $question);
```
After:
```php
$input = new ArrayInput();
$input->setStream($stream);
$questionHelper->ask($input, $output, $question);
```
Before:
```php
$commandTester = new CommandTester($command);
$stream = fopen('php://memory', 'r+', false);
fputs($stream, "AppBundle\nYes");
rewind($stream);
$command->getHelper('question')->setInputStream($stream);
$commandTester->execute();
```
After:
```php
$commandTester = new CommandTester($command);
$commandTester->setInputs(array('AppBundle', 'Yes'));
$commandTester->execute();
```
* The `console.exception` event and the related `ConsoleExceptionEvent` class have
been removed in favor of the `console.error` event and the `ConsoleErrorEvent` class.
* The `SymfonyQuestionHelper::ask` default validation has been removed in favor of `Question::setValidator`.
Debug
-----
* The `ContextErrorException` class has been removed. Use `\ErrorException` instead.
* `FlattenException::getTrace()` now returns additional type descriptions
`integer` and `float`.
* Support for stacked errors in the `ErrorHandler` has been removed
DependencyInjection
-------------------
* Relying on service auto-registration while autowiring is not supported anymore.
Explicitly inject your dependencies or create services whose ids are
their fully-qualified class name.
Before:
```php
namespace App\Controller;
use App\Mailer;
class DefaultController
{
public function __construct(Mailer $mailer) {
// ...
}
// ...
}
```
```yml
services:
App\Controller\DefaultController:
autowire: true
```
After:
```php
// same PHP code
```
```yml
services:
App\Controller\DefaultController:
autowire: true
# or
# App\Controller\DefaultController:
# arguments: { $mailer: "@App\Mailer" }
App\Mailer:
autowire: true
```
* Autowiring services based on the types they implement is not supported anymore. Rename (or alias) your services to their FQCN id to make them autowirable.
* `_defaults` and `_instanceof` are now reserved service names in Yaml configurations. Please rename any services with that names.
* Non-numeric keys in methods and constructors arguments have never been supported and are now forbidden. Please remove them if you happen to have one.
* Service names that start with an underscore are now reserved in Yaml files. Please rename any services with such names.
* Autowiring-types have been removed, use aliases instead.
Before:
```xml
Doctrine\Common\Annotations\Reader
```
After:
```xml
```
* Service identifiers and parameter names are now case sensitive.
* The `Reference` and `Alias` classes do not make service identifiers lowercase anymore.
* Using the `PhpDumper` with an uncompiled `ContainerBuilder` is not supported
anymore.
* Extending the containers generated by `PhpDumper` is not supported
anymore.
* The `DefinitionDecorator` class has been removed. Use the `ChildDefinition`
class instead.
* The `ResolveDefinitionTemplatesPass` class has been removed.
Use the `ResolveChildDefinitionsPass` class instead.
* Using unsupported configuration keys in YAML configuration files raises an
exception.
* Using unsupported options to configure service aliases raises an exception.
* Setting or unsetting a service with the `Container::set()` method is
no longer supported. Only synthetic services can be set or unset.
* Checking the existence of a private service with the `Container::has()`
method is no longer supported and will return `false`.
* Requesting a private service with the `Container::get()` method is no longer
supported.
* The ``strict`` attribute in service arguments has been removed.
The attribute is ignored since 3.0, so you can simply remove it.
* Top-level anonymous services in XML are no longer supported.
EventDispatcher
---------------
* The `ContainerAwareEventDispatcher` class has been removed.
Use `EventDispatcher` with closure factories instead.
ExpressionLanguage
------------------
* The ability to pass a `ParserCacheInterface` instance to the `ExpressionLanguage`
class has been removed. You should use the `CacheItemPoolInterface` interface
instead.
Filesystem
----------
* The `Symfony\Component\Filesystem\LockHandler` has been removed,
use the `Symfony\Component\Lock\Store\FlockStore` class
or the `Symfony\Component\Lock\Store\FlockStore\SemaphoreStore` class directly instead.
Finder
------
* The `ExceptionInterface` has been removed.
* The `Symfony\Component\Finder\Iterator\FilterIterator` class has been
removed as it used to fix a bug which existed before version 5.5.23/5.6.7
Form
----
* The `choices_as_values` option of the `ChoiceType` has been removed.
* Support for data objects that implements both `Traversable` and
`ArrayAccess` in `ResizeFormListener::preSubmit` method has been removed.
* Using callable strings as choice options in ChoiceType is not supported
anymore in favor of passing PropertyPath instances.
Before:
```php
'choice_value' => new PropertyPath('range'),
'choice_label' => 'strtoupper',
```
After:
```php
'choice_value' => 'range',
'choice_label' => function ($choice) {
return strtoupper($choice);
},
```
* Caching of the loaded `ChoiceListInterface` in the `LazyChoiceList` has been removed,
it must be cached in the `ChoiceLoaderInterface` implementation instead.
* Calling `isValid()` on a `Form` instance before submitting it is not supported
anymore and raises an exception.
Before:
```php
if ($form->isValid()) {
// ...
}
```
After:
```php
if ($form->isSubmitted() && $form->isValid()) {
// ...
}
```
* Using the "choices" option in ``CountryType``, ``CurrencyType``, ``LanguageType``,
``LocaleType``, and ``TimezoneType`` without overriding the ``choice_loader``
option is now ignored.
Before:
```php
$builder->add('custom_locales', LocaleType::class, array(
'choices' => $availableLocales,
));
```
After:
```php
$builder->add('custom_locales', LocaleType::class, array(
'choices' => $availableLocales,
'choice_loader' => null,
));
// or
$builder->add('custom_locales', LocaleType::class, array(
'choice_loader' => new CallbackChoiceLoader(function () {
return $this->getAvailableLocales();
}),
));
```
FrameworkBundle
---------------
* The `validator.mapping.cache.doctrine.apc` service has been removed.
* The "framework.trusted_proxies" configuration option and the corresponding "kernel.trusted_proxies" parameter have been removed. Use the `Request::setTrustedProxies()` method in your front controller instead.
* The default value of the `framework.workflows.[name].type` configuration options is now `state_machine`.
* Support for absolute template paths has been removed.
* The following form types registered as services have been removed; use their
fully-qualified class name instead:
- `"form.type.birthday"`
- `"form.type.checkbox"`
- `"form.type.collection"`
- `"form.type.country"`
- `"form.type.currency"`
- `"form.type.date"`
- `"form.type.datetime"`
- `"form.type.email"`
- `"form.type.file"`
- `"form.type.hidden"`
- `"form.type.integer"`
- `"form.type.language"`
- `"form.type.locale"`
- `"form.type.money"`
- `"form.type.number"`
- `"form.type.password"`
- `"form.type.percent"`
- `"form.type.radio"`
- `"form.type.range"`
- `"form.type.repeated"`
- `"form.type.search"`
- `"form.type.textarea"`
- `"form.type.text"`
- `"form.type.time"`
- `"form.type.timezone"`
- `"form.type.url"`
- `"form.type.button"`
- `"form.type.submit"`
- `"form.type.reset"`
* The `framework.serializer.cache` option and the services
`serializer.mapping.cache.apc` and `serializer.mapping.cache.doctrine.apc`
have been removed. APCu should now be automatically used when available.
* The `Symfony\Bundle\FrameworkBundle\DependencyInjection\Compiler\CompilerDebugDumpPass` has been removed.
* The `Symfony\Bundle\FrameworkBundle\DependencyInjection\Compiler\AddConsoleCommandPass` has been removed.
Use `Symfony\Component\Console\DependencyInjection\AddConsoleCommandPass` instead.
* The `Symfony\Bundle\FrameworkBundle\DependencyInjection\Compiler\SerializerPass` class has been removed.
Use the `Symfony\Component\Serializer\DependencyInjection\SerializerPass` class instead.
* The `Symfony\Bundle\FrameworkBundle\DependencyInjection\Compiler\FormPass` class has been
removed. Use the `Symfony\Component\Form\DependencyInjection\FormPass` class instead.
* The `Symfony\Bundle\FrameworkBundle\EventListener\SessionListener` class has been removed.
Use the `Symfony\Component\HttpKernel\EventListener\SessionListener` class instead.
* The `Symfony\Bundle\FrameworkBundle\EventListener\TestSessionListener` class has been
removed. Use the `Symfony\Component\HttpKernel\EventListener\TestSessionListener`
class instead.
* The `Symfony\Bundle\FrameworkBundle\DependencyInjection\Compiler\ConfigCachePass` class has been removed.
Use `Symfony\Component\Config\DependencyInjection\ConfigCachePass` class instead.
* The `Symfony\Bundle\FrameworkBundle\DependencyInjection\Compiler\PropertyInfoPass` class has been
removed. Use the `Symfony\Component\PropertyInfo\DependencyInjection\PropertyInfoPass`
class instead.
* Class parameters related to routing have been removed
* router.options.generator_class
* router.options.generator_base_class
* router.options.generator_dumper_class
* router.options.matcher_class
* router.options.matcher_base_class
* router.options.matcher_dumper_class
* router.options.matcher.cache_class
* router.options.generator.cache_class
* The `Symfony\Bundle\FrameworkBundle\DependencyInjection\Compiler\ControllerArgumentValueResolverPass` class
has been removed. Use the `Symfony\Component\HttpKernel\DependencyInjection\ControllerArgumentValueResolverPass`
class instead.
* The `Symfony\Bundle\FrameworkBundle\DependencyInjection\Compiler\RoutingResolverPass`
class has been removed. Use the
`Symfony\Component\Routing\DependencyInjection\RoutingResolverPass` class instead.
* The `Symfony\Bundle\FrameworkBundle\Translation\Translator` constructor now takes the
default locale as mandatory 3rd argument.
* The `Symfony\Bundle\FrameworkBundle\DependencyInjection\Compiler\AddValidatorInitializersPass` class has been
removed. Use the `Symfony\Component\Validator\DependencyInjection\AddValidatorInitializersPass`
class instead.
* The `Symfony\Bundle\FrameworkBundle\DependencyInjection\Compiler\AddConstraintValidatorsPass` class has been
removed. Use the `Symfony\Component\Validator\DependencyInjection\AddConstraintValidatorsPass`
class instead.
* The `Symfony\Bundle\FrameworkBundle\DependencyInjection\Compiler\ValidateWorkflowsPass` class
has been removed. Use the `Symfony\Component\Workflow\DependencyInjection\ValidateWorkflowsPass`
class instead.
* Using the `KERNEL_DIR` environment variable and the automatic guessing based
on the `phpunit.xml` file location have been removed from the `KernelTestCase::getKernelClass()`
method implementation. Set the `KERNEL_CLASS` environment variable to the
fully-qualified class name of your Kernel or override the `KernelTestCase::createKernel()`
or `KernelTestCase::getKernelClass()` method instead.
* The methods `KernelTestCase::getPhpUnitXmlDir()` and `KernelTestCase::getPhpUnitCliConfigArgument()`
have been removed.
* The `Symfony\Bundle\FrameworkBundle\Validator\ConstraintValidatorFactory` class has been removed.
Use `Symfony\Component\Validator\ContainerConstraintValidatorFactory` instead.
* The `--no-prefix` option of the `translation:update` command has
been removed.
* The `Symfony\Bundle\FrameworkBundle\DependencyInjection\Compiler\AddCacheClearerPass` class has been removed.
Use the `Symfony\Component\HttpKernel\DependencyInjection\AddCacheClearerPass` class instead.
* The `Symfony\Bundle\FrameworkBundle\DependencyInjection\Compiler\AddCacheWarmerPass` class has been removed.
Use the `Symfony\Component\HttpKernel\DependencyInjection\AddCacheWarmerPass` class instead.
* The `Symfony\Bundle\FrameworkBundle\DependencyInjection\Compiler\TranslationDumperPass`
class has been removed. Use the
`Symfony\Component\Translation\DependencyInjection\TranslationDumperPass` class instead.
* The `Symfony\Bundle\FrameworkBundle\DependencyInjection\Compiler\TranslationExtractorPass`
class has been removed. Use the
`Symfony\Component\Translation\DependencyInjection\TranslationExtractorPass` class instead.
* The `Symfony\Bundle\FrameworkBundle\DependencyInjection\Compiler\TranslatorPass`
class has been removed. Use the
`Symfony\Component\Translation\DependencyInjection\TranslatorPass` class instead.
* The `Symfony\Bundle\FrameworkBundle\Translation\TranslationLoader`
class has been deprecated and will be removed in 4.0. Use the
`Symfony\Component\Translation\Reader\TranslationReader` class instead.
* The `translation.loader` service has been removed.
Use the `translation.reader` service instead.
* `AssetsInstallCommand::__construct()` now requires an instance of
`Symfony\Component\Filesystem\Filesystem` as first argument.
* `CacheClearCommand::__construct()` now requires an instance of
`Symfony\Component\HttpKernel\CacheClearer\CacheClearerInterface` as
first argument.
* `CachePoolClearCommand::__construct()` now requires an instance of
`Symfony\Component\HttpKernel\CacheClearer\Psr6CacheClearer` as
first argument.
* `EventDispatcherDebugCommand::__construct()` now requires an instance of
`Symfony\Component\EventDispatcher\EventDispatcherInterface` as
first argument.
* `RouterDebugCommand::__construct()` now requires an instance of
`Symfony\Component\Routing\RouterInteface` as
first argument.
* `RouterMatchCommand::__construct()` now requires an instance of
`Symfony\Component\Routing\RouterInteface` as
first argument.
* `TranslationDebugCommand::__construct()` now requires an instance of
`Symfony\Component\Translation\TranslatorInterface` as
first argument.
* `TranslationUpdateCommand::__construct()` now requires an instance of
`Symfony\Component\Translation\TranslatorInterface` as
first argument.
HttpFoundation
--------------
* The `Request::setTrustedProxies()` method takes a new `$trustedHeaderSet` argument.
See http://symfony.com/doc/current/components/http_foundation/trusting_proxies.html for more info.
* The `Request::setTrustedHeaderName()` and `Request::getTrustedHeaderName()` methods have been removed.
* Extending the following methods of `Response`
is no longer possible (these methods are now `final`):
- `setDate`/`getDate`
- `setExpires`/`getExpires`
- `setLastModified`/`getLastModified`
- `setProtocolVersion`/`getProtocolVersion`
- `setStatusCode`/`getStatusCode`
- `setCharset`/`getCharset`
- `setPrivate`/`setPublic`
- `getAge`
- `getMaxAge`/`setMaxAge`
- `setSharedMaxAge`
- `getTtl`/`setTtl`
- `setClientTtl`
- `getEtag`/`setEtag`
- `hasVary`/`getVary`/`setVary`
- `isInvalid`/`isSuccessful`/`isRedirection`/`isClientError`/`isServerError`
- `isOk`/`isForbidden`/`isNotFound`/`isRedirect`/`isEmpty`
* The ability to check only for cacheable HTTP methods using `Request::isMethodSafe()` is
not supported anymore, use `Request::isMethodCacheable()` instead.
HttpKernel
----------
* Relying on convention-based commands discovery is not supported anymore.
Use PSR-4 based service discovery instead.
Before:
```yml
# app/config/services.yml
services:
# ...
# implicit registration of all commands in the `Command` folder
```
After:
```yml
# app/config/services.yml
services:
# ...
# explicit commands registration
AppBundle\Command:
resource: '../../src/AppBundle/Command/*'
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
renderers has been removed. The inline fragment renderer should be used with
non-scalar attributes.
* The `ControllerResolver::getArguments()` method has been removed. If you
have your own `ControllerResolverInterface` implementation, you should
inject an `ArgumentResolverInterface` instance.
* The `DataCollector::varToString()` method has been removed in favor of `cloneVar()`.
* The `Psr6CacheClearer::addPool()` method has been removed. Pass an array of pools indexed
by name to the constructor instead.
* The `LazyLoadingFragmentHandler::addRendererService()` method has been removed.
* The `X-Status-Code` header method of setting a custom status code in the
response when handling exceptions has been removed. There is now a new
`GetResponseForExceptionEvent::allowCustomResponseCode()` method instead,
which will tell the Kernel to use the response code set on the event's
response object.
* The `Kernel::getEnvParameters()` method has been removed.
* The `SYMFONY__` environment variables are no longer processed automatically
by Symfony. Use the `%env()%` syntax to get the value of any environment
variable from configuration files instead.
* The `getCacheDir()` method of your kernel should not be called while building the container.
Use the `%kernel.cache_dir%` parameter instead. Not doing so may break the `cache:clear` command.
* The `Symfony\Component\HttpKernel\Config\EnvParametersResource` class has been removed.
Ldap
----
* The `RenameEntryInterface` has been removed, and merged with `EntryManagerInterface`
Process
-------
* The `Symfony\Component\Process\ProcessBuilder` class has been removed,
use the `Symfony\Component\Process\Process` class directly instead.
* The `ProcessUtils::escapeArgument()` method has been removed, use a command line array or give env vars to the `Process::start/run()` method instead.
* Environment variables are always inherited in sub-processes.
* Configuring `proc_open()` options has been removed.
* Configuring Windows and sigchild compatibility is not possible anymore - they are always enabled.
* Extending `Process::run()`, `Process::mustRun()` and `Process::restart()` is
not supported anymore.
* The `getEnhanceWindowsCompatibility()` and `setEnhanceWindowsCompatibility()` methods of the `Process` class have been removed.
Profiler
--------
* The `profiler.matcher` option has been removed.
ProxyManager
------------
* The `ProxyDumper` class has been made final
Security
--------
* The `RoleInterface` has been removed. Extend the `Symfony\Component\Security\Core\Role\Role`
class instead.
* The `LogoutUrlGenerator::registerListener()` method expects a 6th `string $context = null` argument.
* The `AccessDecisionManager::setVoters()` method has been removed. Pass the
voters to the constructor instead.
* Support for defining voters that don't implement the `VoterInterface` has been removed.
SecurityBundle
--------------
* The `FirewallContext::getContext()` method has been removed, use the `getListeners()` and/or `getExceptionListener()` method instead.
* The `FirewallMap::$map` and `$container` properties have been removed.
* The `UserPasswordEncoderCommand` class does not allow `null` as the first argument anymore.
* `UserPasswordEncoderCommand` does not extend `ContainerAwareCommand` nor implement `ContainerAwareInterface` anymore.
* `InitAclCommand::__construct()` now requires an instance of
`Doctrine\DBAL\Connection` as first argument.
* `SetAclCommand::__construct()` now requires an instance of
`Symfony\Component\Security\Acl\Model\MutableAclProviderInterfaceConnection`
as first argument.
Serializer
----------
* The ability to pass a Doctrine `Cache` instance to the `ClassMetadataFactory`
class has been removed. You should use the `CacheClassMetadataFactory` class
instead.
* Not defining the 6th argument `$format = null` of the
`AbstractNormalizer::instantiateObject()` method when overriding it is not
supported anymore.
* Extending `ChainDecoder`, `ChainEncoder`, `ArrayDenormalizer` is not supported
anymore.
Translation
-----------
* Removed the backup feature from the file dumper classes.
* The default value of the `$readerServiceId` argument of `TranslatorPass::__construct()` has been changed to `"translation.reader"`.
* Removed `Symfony\Component\Translation\Writer\TranslationWriter::writeTranslations`,
use `Symfony\Component\Translation\Writer\TranslationWriter::write` instead.
* Removed support for passing `Symfony\Component\Translation\MessageSelector` as a second argument to the
`Translator::__construct()`. You should pass an instance of `Symfony\Component\Translation\Formatter\MessageFormatterInterface` instead.
TwigBundle
----------
* The `ContainerAwareRuntimeLoader` class has been removed. Use the
Twig `Twig_ContainerRuntimeLoader` class instead.
* Removed `DebugCommand` in favor of `Symfony\Bridge\Twig\Command\DebugCommand`.
* Removed `ContainerAwareInterface` implementation in `Symfony\Bundle\TwigBundle\Command\LintCommand`.
TwigBridge
----------
* removed the `Symfony\Bridge\Twig\Form\TwigRenderer` class, use the `FormRenderer`
class from the Form component instead
* Removed the possibility to inject the Form `TwigRenderer` into the `FormExtension`.
Upgrade Twig to `^1.30`, inject the `Twig_Environment` into the `TwigRendererEngine` and load
the `TwigRenderer` using the `Twig_FactoryRuntimeLoader` instead.
Before:
```php
use Symfony\Bridge\Twig\Extension\FormExtension;
use Symfony\Bridge\Twig\Form\TwigRenderer;
use Symfony\Bridge\Twig\Form\TwigRendererEngine;
// ...
$rendererEngine = new TwigRendererEngine(array('form_div_layout.html.twig'));
$rendererEngine->setEnvironment($twig);
$twig->addExtension(new FormExtension(new TwigRenderer($rendererEngine, $csrfTokenManager)));
```
After:
```php
$rendererEngine = new TwigRendererEngine(array('form_div_layout.html.twig'), $twig);
$twig->addRuntimeLoader(new \Twig_FactoryRuntimeLoader(array(
TwigRenderer::class => function () use ($rendererEngine, $csrfTokenManager) {
return new TwigRenderer($rendererEngine, $csrfTokenManager);
},
)));
$twig->addExtension(new FormExtension());
```
* Removed the `TwigRendererEngineInterface` interface.
* The `TwigRendererEngine::setEnvironment()` method has been removed.
Pass the Twig Environment as second argument of the constructor instead.
* Removed `DebugCommand::set/getTwigEnvironment`. Pass an instance of
`Twig\Environment` as first argument of the constructor instead.
* Removed `LintCommand::set/getTwigEnvironment`. Pass an instance of
`Twig\Environment` as first argument of the constructor instead.
Validator
---------
* The default value of the `strict` option of the `Choice` constraint was changed
to `true`. Using any other value will throw an exception.
* The `DateTimeValidator::PATTERN` constant was removed.
* `Tests\Constraints\AbstractConstraintValidatorTest` has been removed in
favor of `Test\ConstraintValidatorTestCase`.
Before:
```php
// ...
use Symfony\Component\Validator\Tests\Constraints\AbstractConstraintValidatorTest;
class MyCustomValidatorTest extends AbstractConstraintValidatorTest
{
// ...
}
```
After:
```php
// ...
use Symfony\Component\Validator\Test\ConstraintValidatorTestCase;
class MyCustomValidatorTest extends ConstraintValidatorTestCase
{
// ...
}
```
* Setting the `checkDNS` option of the `Url` constraint to `true` is dropped
in favor of `Url::CHECK_DNS_TYPE_*` constants values.
Before:
```php
$constraint = new Url(['checkDNS' => true]);
```
After:
```php
$constraint = new Url(['checkDNS' => Url::CHECK_DNS_TYPE_ANY]);
```
VarDumper
---------
* The `VarDumperTestTrait::assertDumpEquals()` method expects a 3rd `$context = null`
argument and moves `$message = ''` argument at 4th position.
Before:
```php
VarDumperTestTrait::assertDumpEquals($dump, $data, $message = '');
```
After:
```php
VarDumperTestTrait::assertDumpEquals($dump, $data, $filter = 0, $message = '');
```
* The `VarDumperTestTrait::assertDumpMatchesFormat()` method expects a 3rd `$context = null`
argument and moves `$message = ''` argument at 4th position.
Before:
```php
VarDumperTestTrait::assertDumpMatchesFormat($dump, $data, $message = '');
```
After:
```php
VarDumperTestTrait::assertDumpMatchesFormat($dump, $data, $filter = 0, $message = '');
```
WebProfilerBundle
-----------------
* Removed the `getTemplates()` method of the `TemplateManager` class in favor
of the `getNames()` method
Workflow
--------
* Removed class name support in `WorkflowRegistry::add()` as second parameter.
Yaml
----
* Support for the `!str` tag was removed, use the `!!str` tag instead.
* Starting an unquoted string with a question mark followed by a space
throws a `ParseException`.
* Removed support for implicitly parsing non-string mapping keys as strings.
Mapping keys that are no strings will result in a `ParseException`. Use
quotes to opt-in for keys to be parsed as strings.
Before:
```php
$yaml = << new A(), 'bar' => 1), 0, 0, true);
```
After:
```php
Yaml::dump(array('foo' => new A(), 'bar' => 1), 0, 0, Yaml::DUMP_EXCEPTION_ON_INVALID_TYPE);
```
* Removed support for passing `true`/`false` as the fifth argument to the
`dump()` method to toggle object support.
Before:
```php
Yaml::dump(array('foo' => new A(), 'bar' => 1), 0, 0, false, true);
```
After:
```php
Yaml::dump(array('foo' => new A(), 'bar' => 1), 0, 0, false, Yaml::DUMP_OBJECT);
```
* The `!!php/object` tag to indicate dumped PHP objects was removed in favor of
the `!php/object` tag.
* Duplicate mapping keys lead to a `ParseException`.
* The constructor arguments `$offset`, `$totalNumberOfLines` and
`$skippedLineNumbers` of the `Parser` class were removed.
* The behavior of the non-specific tag `!` is changed and now forces
non-evaluating your values.
* The `!php/object:` tag was removed in favor of the `!php/object` tag (without
the colon).
* The `!php/const:` tag was removed in favor of the `!php/const` tag (without
the colon).
Before:
```yml
!php/const:PHP_INT_MAX
```
After:
```yml
!php/const PHP_INT_MAX
```