From d870a850bd71fd1fc0b340cc291f62868f52d317 Mon Sep 17 00:00:00 2001
From: Nyholm <tobias.nyholm@gmail.com>
Date: Wed, 5 Sep 2018 21:29:06 +0200
Subject: [PATCH 1/2] [Translator] Deprecated transChoice and moved it away
 from contracts

---
 UPGRADE-4.2.md                                |   1 +
 .../Twig/Extension/TranslationExtension.php   |   7 +-
 .../Templating/Helper/TranslatorHelper.php    |   7 +-
 .../Tests/Translation/TranslatorTest.php      |  44 ++-
 .../Component/Translation/CHANGELOG.md        |   1 +
 .../Translation/DataCollectorTranslator.php   |  11 +-
 .../Translation/IdentityTranslator.php        |  11 +-
 .../Translation/LegacyTranslatorTrait.php     | 110 +++++++
 .../Translation/LoggingTranslator.php         |  11 +-
 .../Component/Translation/MessageSelector.php |   6 +-
 .../Tests/DataCollectorTranslatorTest.php     |  34 ++-
 .../Tests/Formatter/MessageFormatterTest.php  |   1 +
 .../Tests/IdentityTranslatorTest.php          | 189 ++++++++++++
 .../Tests/LoggingTranslatorTest.php           |  22 +-
 .../Translation/Tests/TranslatorTest.php      |  12 +
 .../Component/Translation/Translator.php      |   1 +
 .../Translation/TranslatorInterface.php       |  48 ++-
 .../Validator/Util/LegacyTranslatorProxy.php  |  10 +-
 .../Violation/ConstraintViolationBuilder.php  |   3 +-
 .../Tests/Translation/TranslatorTest.php      | 274 ------------------
 .../Translation/TranslatorInterface.php       |  45 ---
 .../Contracts/Translation/TranslatorTrait.php | 212 --------------
 22 files changed, 494 insertions(+), 566 deletions(-)
 create mode 100644 src/Symfony/Component/Translation/LegacyTranslatorTrait.php

diff --git a/UPGRADE-4.2.md b/UPGRADE-4.2.md
index 18b88f2fa2..95f2b980c8 100644
--- a/UPGRADE-4.2.md
+++ b/UPGRADE-4.2.md
@@ -219,6 +219,7 @@ Translation
 -----------
 
  * The `TranslatorInterface` has been deprecated in favor of `Symfony\Contracts\Translation\TranslatorInterface`
+ * The `Translator::transChoice()` has been deprecated in favor of using `Translator::trans()` with intl message format
  * The `MessageSelector`, `Interval` and `PluralizationRules` classes have been deprecated, use `IdentityTranslator` instead
  * The `Translator::getFallbackLocales()` and `TranslationDataCollector::getFallbackLocales()` method have been marked as internal
 
diff --git a/src/Symfony/Bridge/Twig/Extension/TranslationExtension.php b/src/Symfony/Bridge/Twig/Extension/TranslationExtension.php
index 607302d991..090aed5548 100644
--- a/src/Symfony/Bridge/Twig/Extension/TranslationExtension.php
+++ b/src/Symfony/Bridge/Twig/Extension/TranslationExtension.php
@@ -16,6 +16,8 @@ use Symfony\Bridge\Twig\NodeVisitor\TranslationNodeVisitor;
 use Symfony\Bridge\Twig\TokenParser\TransChoiceTokenParser;
 use Symfony\Bridge\Twig\TokenParser\TransDefaultDomainTokenParser;
 use Symfony\Bridge\Twig\TokenParser\TransTokenParser;
+use Symfony\Component\Translation\LegacyTranslatorTrait;
+use Symfony\Component\Translation\TranslatorInterface as LegacyTranslatorInterface;
 use Symfony\Contracts\Translation\TranslatorInterface;
 use Symfony\Contracts\Translation\TranslatorTrait;
 use Twig\Extension\AbstractExtension;
@@ -34,6 +36,9 @@ class TranslationExtension extends AbstractExtension
         getLocale as private;
         setLocale as private;
         trans as private doTrans;
+    }
+
+    use LegacyTranslatorTrait {
         transChoice as private doTransChoice;
     }
 
@@ -107,7 +112,7 @@ class TranslationExtension extends AbstractExtension
 
     public function transchoice($message, $count, array $arguments = array(), $domain = null, $locale = null)
     {
-        if (null === $this->translator) {
+        if (null === $this->translator || !$this->translator instanceof LegacyTranslatorInterface) {
             return $this->doTransChoice($message, $count, array_merge(array('%count%' => $count), $arguments), $domain, $locale);
         }
 
diff --git a/src/Symfony/Bundle/FrameworkBundle/Templating/Helper/TranslatorHelper.php b/src/Symfony/Bundle/FrameworkBundle/Templating/Helper/TranslatorHelper.php
index b3dd76d42a..2052fef695 100644
--- a/src/Symfony/Bundle/FrameworkBundle/Templating/Helper/TranslatorHelper.php
+++ b/src/Symfony/Bundle/FrameworkBundle/Templating/Helper/TranslatorHelper.php
@@ -12,6 +12,8 @@
 namespace Symfony\Bundle\FrameworkBundle\Templating\Helper;
 
 use Symfony\Component\Templating\Helper\Helper;
+use Symfony\Component\Translation\LegacyTranslatorTrait;
+use Symfony\Component\Translation\TranslatorInterface as LegacyTranslatorInterface;
 use Symfony\Contracts\Translation\TranslatorInterface;
 use Symfony\Contracts\Translation\TranslatorTrait;
 
@@ -24,6 +26,9 @@ class TranslatorHelper extends Helper
         getLocale as private;
         setLocale as private;
         trans as private doTrans;
+    }
+
+    use LegacyTranslatorTrait {
         transChoice as private doTransChoice;
     }
 
@@ -51,7 +56,7 @@ class TranslatorHelper extends Helper
      */
     public function transChoice($id, $number, array $parameters = array(), $domain = 'messages', $locale = null)
     {
-        if (null === $this->translator) {
+        if (null === $this->translator || !$this->translator instanceof LegacyTranslatorInterface) {
             return $this->doTransChoice($id, $number, $parameters, $domain, $locale);
         }
 
diff --git a/src/Symfony/Bundle/FrameworkBundle/Tests/Translation/TranslatorTest.php b/src/Symfony/Bundle/FrameworkBundle/Tests/Translation/TranslatorTest.php
index eeb4e0daa4..93e070040b 100644
--- a/src/Symfony/Bundle/FrameworkBundle/Tests/Translation/TranslatorTest.php
+++ b/src/Symfony/Bundle/FrameworkBundle/Tests/Translation/TranslatorTest.php
@@ -52,14 +52,25 @@ class TranslatorTest extends TestCase
         $this->assertEquals('foo (FR)', $translator->trans('foo'));
         $this->assertEquals('bar (EN)', $translator->trans('bar'));
         $this->assertEquals('foobar (ES)', $translator->trans('foobar'));
-        $this->assertEquals('choice 0 (EN)', $translator->transChoice('choice', 0));
         $this->assertEquals('no translation', $translator->trans('no translation'));
         $this->assertEquals('foobarfoo (PT-PT)', $translator->trans('foobarfoo'));
-        $this->assertEquals('other choice 1 (PT-BR)', $translator->transChoice('other choice', 1));
         $this->assertEquals('foobarbaz (fr.UTF-8)', $translator->trans('foobarbaz'));
         $this->assertEquals('foobarbax (sr@latin)', $translator->trans('foobarbax'));
     }
 
+    /**
+     * @group legacy
+     */
+    public function testTransChoiceWithoutCaching()
+    {
+        $translator = $this->getTranslator($this->getLoader());
+        $translator->setLocale('fr');
+        $translator->setFallbackLocales(array('en', 'es', 'pt-PT', 'pt_BR', 'fr.UTF-8', 'sr@latin'));
+
+        $this->assertEquals('choice 0 (EN)', $translator->transChoice('choice', 0));
+        $this->assertEquals('other choice 1 (PT-BR)', $translator->transChoice('other choice', 1));
+    }
+
     public function testTransWithCaching()
     {
         // prime the cache
@@ -70,10 +81,8 @@ class TranslatorTest extends TestCase
         $this->assertEquals('foo (FR)', $translator->trans('foo'));
         $this->assertEquals('bar (EN)', $translator->trans('bar'));
         $this->assertEquals('foobar (ES)', $translator->trans('foobar'));
-        $this->assertEquals('choice 0 (EN)', $translator->transChoice('choice', 0));
         $this->assertEquals('no translation', $translator->trans('no translation'));
         $this->assertEquals('foobarfoo (PT-PT)', $translator->trans('foobarfoo'));
-        $this->assertEquals('other choice 1 (PT-BR)', $translator->transChoice('other choice', 1));
         $this->assertEquals('foobarbaz (fr.UTF-8)', $translator->trans('foobarbaz'));
         $this->assertEquals('foobarbax (sr@latin)', $translator->trans('foobarbax'));
 
@@ -88,14 +97,37 @@ class TranslatorTest extends TestCase
         $this->assertEquals('foo (FR)', $translator->trans('foo'));
         $this->assertEquals('bar (EN)', $translator->trans('bar'));
         $this->assertEquals('foobar (ES)', $translator->trans('foobar'));
-        $this->assertEquals('choice 0 (EN)', $translator->transChoice('choice', 0));
         $this->assertEquals('no translation', $translator->trans('no translation'));
         $this->assertEquals('foobarfoo (PT-PT)', $translator->trans('foobarfoo'));
-        $this->assertEquals('other choice 1 (PT-BR)', $translator->transChoice('other choice', 1));
         $this->assertEquals('foobarbaz (fr.UTF-8)', $translator->trans('foobarbaz'));
         $this->assertEquals('foobarbax (sr@latin)', $translator->trans('foobarbax'));
     }
 
+    /**
+     * @group legacy
+     */
+    public function testTransChoiceWithCaching()
+    {
+        // prime the cache
+        $translator = $this->getTranslator($this->getLoader(), array('cache_dir' => $this->tmpDir));
+        $translator->setLocale('fr');
+        $translator->setFallbackLocales(array('en', 'es', 'pt-PT', 'pt_BR', 'fr.UTF-8', 'sr@latin'));
+
+        $this->assertEquals('choice 0 (EN)', $translator->transChoice('choice', 0));
+        $this->assertEquals('other choice 1 (PT-BR)', $translator->transChoice('other choice', 1));
+
+        // do it another time as the cache is primed now
+        $loader = $this->getMockBuilder('Symfony\Component\Translation\Loader\LoaderInterface')->getMock();
+        $loader->expects($this->never())->method('load');
+
+        $translator = $this->getTranslator($loader, array('cache_dir' => $this->tmpDir));
+        $translator->setLocale('fr');
+        $translator->setFallbackLocales(array('en', 'es', 'pt-PT', 'pt_BR', 'fr.UTF-8', 'sr@latin'));
+
+        $this->assertEquals('choice 0 (EN)', $translator->transChoice('choice', 0));
+        $this->assertEquals('other choice 1 (PT-BR)', $translator->transChoice('other choice', 1));
+    }
+
     /**
      * @expectedException \InvalidArgumentException
      * @expectedExceptionMessage Invalid "invalid locale" locale.
diff --git a/src/Symfony/Component/Translation/CHANGELOG.md b/src/Symfony/Component/Translation/CHANGELOG.md
index 6bbecdd099..87b7e5a9f1 100644
--- a/src/Symfony/Component/Translation/CHANGELOG.md
+++ b/src/Symfony/Component/Translation/CHANGELOG.md
@@ -5,6 +5,7 @@ CHANGELOG
 -----
 
  * Started using ICU parent locales as fallback locales.
+ * deprecated `Translator::transChoice()` in favor of using `Translator::trans()` with intl message format 
  * deprecated `TranslatorInterface` in favor of `Symfony\Contracts\Translation\TranslatorInterface`
  * deprecated `MessageSelector`, `Interval` and `PluralizationRules`; use `IdentityTranslator` instead
  * Added `IntlMessageFormatter` and `FallbackMessageFormatter`
diff --git a/src/Symfony/Component/Translation/DataCollectorTranslator.php b/src/Symfony/Component/Translation/DataCollectorTranslator.php
index 10ac93516b..fd8c135e26 100644
--- a/src/Symfony/Component/Translation/DataCollectorTranslator.php
+++ b/src/Symfony/Component/Translation/DataCollectorTranslator.php
@@ -20,6 +20,10 @@ use Symfony\Contracts\Translation\TranslatorInterface;
  */
 class DataCollectorTranslator implements LegacyTranslatorInterface, TranslatorBagInterface
 {
+    use LegacyTranslatorTrait {
+        transChoice as private doTransChoice;
+    }
+
     const MESSAGE_DEFINED = 0;
     const MESSAGE_MISSING = 1;
     const MESSAGE_EQUALS_FALLBACK = 2;
@@ -59,7 +63,12 @@ class DataCollectorTranslator implements LegacyTranslatorInterface, TranslatorBa
      */
     public function transChoice($id, $number, array $parameters = array(), $domain = null, $locale = null)
     {
-        $trans = $this->translator->transChoice($id, $number, $parameters, $domain, $locale);
+        if ($this->translator instanceof LegacyTranslatorInterface) {
+            $trans = $this->translator->transChoice($id, $number, $parameters, $domain, $locale);
+        } else {
+            $trans = $this->doTransChoice($id, $number, $parameters, $domain, $locale);
+        }
+
         $this->collectMessage($locale, $domain, $id, $trans, $parameters, $number);
 
         return $trans;
diff --git a/src/Symfony/Component/Translation/IdentityTranslator.php b/src/Symfony/Component/Translation/IdentityTranslator.php
index b69312ec79..c138563049 100644
--- a/src/Symfony/Component/Translation/IdentityTranslator.php
+++ b/src/Symfony/Component/Translation/IdentityTranslator.php
@@ -20,7 +20,8 @@ use Symfony\Contracts\Translation\TranslatorTrait;
  */
 class IdentityTranslator implements TranslatorInterface
 {
-    use TranslatorTrait {
+    use TranslatorTrait;
+    use LegacyTranslatorTrait {
         transChoice as private doTransChoice;
     }
 
@@ -43,15 +44,11 @@ class IdentityTranslator implements TranslatorInterface
      */
     public function transChoice($id, $number, array $parameters = array(), $domain = null, $locale = null)
     {
+        @trigger_error(sprintf('The "%s()" method is deprecated since Symfony 4.2, use the "trans()" method with intl formatted messages instead.', __METHOD__), E_USER_DEPRECATED);
         if ($this->selector) {
-            return strtr($this->selector->choose((string) $id, (int) $number, $locale ?: $this->getLocale()), $parameters);
+            return strtr($this->selector->choose((string) $id, $number, $locale ?: $this->getLocale()), $parameters);
         }
 
         return $this->doTransChoice($id, $number, $parameters, $domain, $locale);
     }
-
-    private function getPluralizationRule(int $number, string $locale): int
-    {
-        return PluralizationRules::get($number, $locale, false);
-    }
 }
diff --git a/src/Symfony/Component/Translation/LegacyTranslatorTrait.php b/src/Symfony/Component/Translation/LegacyTranslatorTrait.php
new file mode 100644
index 0000000000..1b24372206
--- /dev/null
+++ b/src/Symfony/Component/Translation/LegacyTranslatorTrait.php
@@ -0,0 +1,110 @@
+<?php
+
+/*
+ * This file is part of the Symfony package.
+ *
+ * (c) Fabien Potencier <fabien@symfony.com>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Symfony\Component\Translation;
+
+use Symfony\Component\Translation\Exception\InvalidArgumentException;
+
+/**
+ * @author Tobias Nyholm <tobias.nyholm@gmail.com>
+ * @author Fabien Potencier <fabien@symfony.com>
+ *
+ * @deprecated since Symfony 4.2, use IdentityTranslator instead
+ */
+trait LegacyTranslatorTrait
+{
+    /**
+     * Implementation of Symfony\Component\Translation\TranslationInterface::transChoice
+     * {@inheritdoc}
+     */
+    public function transChoice($id, $number, array $parameters = array(), $domain = null, $locale = null)
+    {
+        @trigger_error(sprintf('The "%s()" method is deprecated since Symfony 4.2, use the "trans()" method with intl formatted messages instead.', __METHOD__), E_USER_DEPRECATED);
+
+        $id = (string) $id;
+        $number = (float) $number;
+        $locale = (string) $locale ?: $this->getLocale();
+
+        $parts = array();
+        if (preg_match('/^\|++$/', $id)) {
+            $parts = explode('|', $id);
+        } elseif (preg_match_all('/(?:\|\||[^\|])++/', $id, $matches)) {
+            $parts = $matches[0];
+        }
+
+        $intervalRegexp = <<<'EOF'
+/^(?P<interval>
+    ({\s*
+        (\-?\d+(\.\d+)?[\s*,\s*\-?\d+(\.\d+)?]*)
+    \s*})
+
+        |
+
+    (?P<left_delimiter>[\[\]])
+        \s*
+        (?P<left>-Inf|\-?\d+(\.\d+)?)
+        \s*,\s*
+        (?P<right>\+?Inf|\-?\d+(\.\d+)?)
+        \s*
+    (?P<right_delimiter>[\[\]])
+)\s*(?P<message>.*?)$/xs
+EOF;
+
+        $standardRules = array();
+        foreach ($parts as $part) {
+            $part = trim(str_replace('||', '|', $part));
+
+            // try to match an explicit rule, then fallback to the standard ones
+            if (preg_match($intervalRegexp, $part, $matches)) {
+                if ($matches[2]) {
+                    foreach (explode(',', $matches[3]) as $n) {
+                        if ($number == $n) {
+                            return strtr($matches['message'], $parameters);
+                        }
+                    }
+                } else {
+                    $leftNumber = '-Inf' === $matches['left'] ? -INF : (float) $matches['left'];
+                    $rightNumber = \is_numeric($matches['right']) ? (float) $matches['right'] : INF;
+
+                    if (('[' === $matches['left_delimiter'] ? $number >= $leftNumber : $number > $leftNumber)
+                        && (']' === $matches['right_delimiter'] ? $number <= $rightNumber : $number < $rightNumber)
+                    ) {
+                        return strtr($matches['message'], $parameters);
+                    }
+                }
+            } elseif (preg_match('/^\w+\:\s*(.*?)$/', $part, $matches)) {
+                $standardRules[] = $matches[1];
+            } else {
+                $standardRules[] = $part;
+            }
+        }
+
+        $position = PluralizationRules::get($number, $locale, false);
+
+        if (!isset($standardRules[$position])) {
+            // when there's exactly one rule given, and that rule is a standard
+            // rule, use this rule
+            if (1 === \count($parts) && isset($standardRules[0])) {
+                return strtr($standardRules[0], $parameters);
+            }
+
+            $message = sprintf('Unable to choose a translation for "%s" with locale "%s" for value "%d". Double check that this translation has the correct plural options (e.g. "There is one apple|There are %%count%% apples").', $id, $locale, $number);
+
+            if (\class_exists(InvalidArgumentException::class)) {
+                throw new InvalidArgumentException($message);
+            }
+
+            throw new \InvalidArgumentException($message);
+        }
+
+        return strtr($standardRules[$position], $parameters);
+    }
+}
diff --git a/src/Symfony/Component/Translation/LoggingTranslator.php b/src/Symfony/Component/Translation/LoggingTranslator.php
index cfb60ab0b0..7a10952a2a 100644
--- a/src/Symfony/Component/Translation/LoggingTranslator.php
+++ b/src/Symfony/Component/Translation/LoggingTranslator.php
@@ -21,6 +21,10 @@ use Symfony\Contracts\Translation\TranslatorInterface;
  */
 class LoggingTranslator implements LegacyTranslatorInterface, TranslatorBagInterface
 {
+    use LegacyTranslatorTrait {
+        transChoice as private doTransChoice;
+    }
+
     /**
      * @var TranslatorInterface|TranslatorBagInterface
      */
@@ -58,7 +62,12 @@ class LoggingTranslator implements LegacyTranslatorInterface, TranslatorBagInter
      */
     public function transChoice($id, $number, array $parameters = array(), $domain = null, $locale = null)
     {
-        $trans = $this->translator->transChoice($id, $number, $parameters, $domain, $locale);
+        if ($this->translator instanceof LegacyTranslatorInterface) {
+            $trans = $this->translator->transChoice($id, $number, $parameters, $domain, $locale);
+        } else {
+            $trans = $this->doTransChoice($id, $number, $parameters, $domain, $locale);
+        }
+
         $this->log($id, $domain, $locale);
 
         return $trans;
diff --git a/src/Symfony/Component/Translation/MessageSelector.php b/src/Symfony/Component/Translation/MessageSelector.php
index 867a345ced..06639417b6 100644
--- a/src/Symfony/Component/Translation/MessageSelector.php
+++ b/src/Symfony/Component/Translation/MessageSelector.php
@@ -43,9 +43,9 @@ class MessageSelector
      * The two methods can also be mixed:
      *     {0} There are no apples|one: There is one apple|more: There are %count% apples
      *
-     * @param string $message The message being translated
-     * @param int    $number  The number of items represented for the message
-     * @param string $locale  The locale to use for choosing
+     * @param string    $message The message being translated
+     * @param int|float $number  The number of items represented for the message
+     * @param string    $locale  The locale to use for choosing
      *
      * @return string
      *
diff --git a/src/Symfony/Component/Translation/Tests/DataCollectorTranslatorTest.php b/src/Symfony/Component/Translation/Tests/DataCollectorTranslatorTest.php
index 1cdd33b395..ae15339bce 100644
--- a/src/Symfony/Component/Translation/Tests/DataCollectorTranslatorTest.php
+++ b/src/Symfony/Component/Translation/Tests/DataCollectorTranslatorTest.php
@@ -25,7 +25,6 @@ class DataCollectorTranslatorTest extends TestCase
 
         $collector->trans('foo');
         $collector->trans('bar');
-        $collector->transChoice('choice', 0);
         $collector->trans('bar_ru');
         $collector->trans('bar_ru', array('foo' => 'bar'));
 
@@ -48,15 +47,6 @@ class DataCollectorTranslatorTest extends TestCase
             'parameters' => array(),
             'transChoiceNumber' => null,
         );
-        $expectedMessages[] = array(
-            'id' => 'choice',
-            'translation' => 'choice',
-            'locale' => 'en',
-            'domain' => 'messages',
-            'state' => DataCollectorTranslator::MESSAGE_MISSING,
-            'parameters' => array(),
-            'transChoiceNumber' => 0,
-        );
         $expectedMessages[] = array(
             'id' => 'bar_ru',
             'translation' => 'bar (ru)',
@@ -79,6 +69,30 @@ class DataCollectorTranslatorTest extends TestCase
         $this->assertEquals($expectedMessages, $collector->getCollectedMessages());
     }
 
+    /**
+     * @group legacy
+     */
+    public function testCollectMessagesTransChoice()
+    {
+        $collector = $this->createCollector();
+        $collector->setFallbackLocales(array('fr', 'ru'));
+        $collector->transChoice('choice', 0);
+
+        $expectedMessages = array();
+
+        $expectedMessages[] = array(
+              'id' => 'choice',
+              'translation' => 'choice',
+              'locale' => 'en',
+              'domain' => 'messages',
+              'state' => DataCollectorTranslator::MESSAGE_MISSING,
+              'parameters' => array(),
+              'transChoiceNumber' => 0,
+        );
+
+        $this->assertEquals($expectedMessages, $collector->getCollectedMessages());
+    }
+
     private function createCollector()
     {
         $translator = new Translator('en');
diff --git a/src/Symfony/Component/Translation/Tests/Formatter/MessageFormatterTest.php b/src/Symfony/Component/Translation/Tests/Formatter/MessageFormatterTest.php
index 1fa736e7e3..f4c96aa12f 100644
--- a/src/Symfony/Component/Translation/Tests/Formatter/MessageFormatterTest.php
+++ b/src/Symfony/Component/Translation/Tests/Formatter/MessageFormatterTest.php
@@ -26,6 +26,7 @@ class MessageFormatterTest extends TestCase
 
     /**
      * @dataProvider getTransChoiceMessages
+     * @group legacy
      */
     public function testFormatPlural($expected, $message, $number, $parameters)
     {
diff --git a/src/Symfony/Component/Translation/Tests/IdentityTranslatorTest.php b/src/Symfony/Component/Translation/Tests/IdentityTranslatorTest.php
index be0a548aa1..443c63718e 100644
--- a/src/Symfony/Component/Translation/Tests/IdentityTranslatorTest.php
+++ b/src/Symfony/Component/Translation/Tests/IdentityTranslatorTest.php
@@ -20,4 +20,193 @@ class IdentityTranslatorTest extends TranslatorTest
     {
         return new IdentityTranslator();
     }
+
+    /**
+     * @dataProvider getTransChoiceTests
+     * @group legacy
+     */
+    public function testTransChoiceWithExplicitLocale($expected, $id, $number, $parameters)
+    {
+        $translator = $this->getTranslator();
+        $translator->setLocale('en');
+
+        $this->assertEquals($expected, $translator->transChoice($id, $number, $parameters));
+    }
+
+    /**
+     * @dataProvider getTransChoiceTests
+     * @group legacy
+     */
+    public function testTransChoiceWithDefaultLocale($expected, $id, $number, $parameters)
+    {
+        \Locale::setDefault('en');
+
+        $translator = $this->getTranslator();
+
+        $this->assertEquals($expected, $translator->transChoice($id, $number, $parameters));
+    }
+
+    /**
+     * @dataProvider getInternal
+     * @group legacy
+     */
+    public function testInterval($expected, $number, $interval)
+    {
+        $translator = $this->getTranslator();
+
+        $this->assertEquals($expected, $translator->transChoice($interval.' foo|[1,Inf[ bar', $number));
+    }
+
+    /**
+     * @dataProvider getChooseTests
+     * @group legacy
+     */
+    public function testChoose($expected, $id, $number)
+    {
+        $translator = $this->getTranslator();
+
+        $this->assertEquals($expected, $translator->transChoice($id, $number));
+    }
+
+    /**
+     * @group legacy
+     */
+    public function testReturnMessageIfExactlyOneStandardRuleIsGiven()
+    {
+        $translator = $this->getTranslator();
+
+        $this->assertEquals('There are two apples', $translator->transChoice('There are two apples', 2));
+    }
+
+    /**
+     * @dataProvider getNonMatchingMessages
+     * @expectedException \InvalidArgumentException
+     * @group legacy
+     */
+    public function testThrowExceptionIfMatchingMessageCannotBeFound($id, $number)
+    {
+        $translator = $this->getTranslator();
+
+        $translator->transChoice($id, $number);
+    }
+
+    public function getTransChoiceTests()
+    {
+        return array(
+            array('There are no apples', '{0} There are no apples|{1} There is one apple|]1,Inf] There are %count% apples', 0, array('%count%' => 0)),
+            array('There is one apple', '{0} There are no apples|{1} There is one apple|]1,Inf] There are %count% apples', 1, array('%count%' => 1)),
+            array('There are 10 apples', '{0} There are no apples|{1} There is one apple|]1,Inf] There are %count% apples', 10, array('%count%' => 10)),
+            array('There are 0 apples', 'There is 1 apple|There are %count% apples', 0, array('%count%' => 0)),
+            array('There is 1 apple', 'There is 1 apple|There are %count% apples', 1, array('%count%' => 1)),
+            array('There are 10 apples', 'There is 1 apple|There are %count% apples', 10, array('%count%' => 10)),
+            // custom validation messages may be coded with a fixed value
+            array('There are 2 apples', 'There are 2 apples', 2, array('%count%' => 2)),
+        );
+    }
+
+    public function getInternal()
+    {
+        return array(
+            array('foo', 3, '{1,2, 3 ,4}'),
+            array('bar', 10, '{1,2, 3 ,4}'),
+            array('bar', 3, '[1,2]'),
+            array('foo', 1, '[1,2]'),
+            array('foo', 2, '[1,2]'),
+            array('bar', 1, ']1,2['),
+            array('bar', 2, ']1,2['),
+            array('foo', log(0), '[-Inf,2['),
+            array('foo', -log(0), '[-2,+Inf]'),
+        );
+    }
+
+    public function getNonMatchingMessages()
+    {
+        return array(
+            array('{0} There are no apples|{1} There is one apple', 2),
+            array('{1} There is one apple|]1,Inf] There are %count% apples', 0),
+            array('{1} There is one apple|]2,Inf] There are %count% apples', 2),
+            array('{0} There are no apples|There is one apple', 2),
+        );
+    }
+
+    public function getChooseTests()
+    {
+        return array(
+            array('There are no apples', '{0} There are no apples|{1} There is one apple|]1,Inf] There are %count% apples', 0),
+            array('There are no apples', '{0}     There are no apples|{1} There is one apple|]1,Inf] There are %count% apples', 0),
+            array('There are no apples', '{0}There are no apples|{1} There is one apple|]1,Inf] There are %count% apples', 0),
+
+            array('There is one apple', '{0} There are no apples|{1} There is one apple|]1,Inf] There are %count% apples', 1),
+
+            array('There are %count% apples', '{0} There are no apples|{1} There is one apple|]1,Inf] There are %count% apples', 10),
+            array('There are %count% apples', '{0} There are no apples|{1} There is one apple|]1,Inf]There are %count% apples', 10),
+            array('There are %count% apples', '{0} There are no apples|{1} There is one apple|]1,Inf]     There are %count% apples', 10),
+
+            array('There are %count% apples', 'There is one apple|There are %count% apples', 0),
+            array('There is one apple', 'There is one apple|There are %count% apples', 1),
+            array('There are %count% apples', 'There is one apple|There are %count% apples', 10),
+
+            array('There are %count% apples', 'one: There is one apple|more: There are %count% apples', 0),
+            array('There is one apple', 'one: There is one apple|more: There are %count% apples', 1),
+            array('There are %count% apples', 'one: There is one apple|more: There are %count% apples', 10),
+
+            array('There are no apples', '{0} There are no apples|one: There is one apple|more: There are %count% apples', 0),
+            array('There is one apple', '{0} There are no apples|one: There is one apple|more: There are %count% apples', 1),
+            array('There are %count% apples', '{0} There are no apples|one: There is one apple|more: There are %count% apples', 10),
+
+            array('', '{0}|{1} There is one apple|]1,Inf] There are %count% apples', 0),
+            array('', '{0} There are no apples|{1}|]1,Inf] There are %count% apples', 1),
+
+            // Indexed only tests which are Gettext PoFile* compatible strings.
+            array('There are %count% apples', 'There is one apple|There are %count% apples', 0),
+            array('There is one apple', 'There is one apple|There are %count% apples', 1),
+            array('There are %count% apples', 'There is one apple|There are %count% apples', 2),
+
+            // Tests for float numbers
+            array('There is almost one apple', '{0} There are no apples|]0,1[ There is almost one apple|{1} There is one apple|[1,Inf] There is more than one apple', 0.7),
+            array('There is one apple', '{0} There are no apples|]0,1[There are %count% apples|{1} There is one apple|[1,Inf] There is more than one apple', 1),
+            array('There is more than one apple', '{0} There are no apples|]0,1[There are %count% apples|{1} There is one apple|[1,Inf] There is more than one apple', 1.7),
+            array('There are no apples', '{0} There are no apples|]0,1[There are %count% apples|{1} There is one apple|[1,Inf] There is more than one apple', 0),
+            array('There are no apples', '{0} There are no apples|]0,1[There are %count% apples|{1} There is one apple|[1,Inf] There is more than one apple', 0.0),
+            array('There are no apples', '{0.0} There are no apples|]0,1[There are %count% apples|{1} There is one apple|[1,Inf] There is more than one apple', 0),
+
+            // Test texts with new-lines
+            // with double-quotes and \n in id & double-quotes and actual newlines in text
+            array("This is a text with a\n            new-line in it. Selector = 0.", '{0}This is a text with a
+            new-line in it. Selector = 0.|{1}This is a text with a
+            new-line in it. Selector = 1.|[1,Inf]This is a text with a
+            new-line in it. Selector > 1.', 0),
+            // with double-quotes and \n in id and single-quotes and actual newlines in text
+            array("This is a text with a\n            new-line in it. Selector = 1.", '{0}This is a text with a
+            new-line in it. Selector = 0.|{1}This is a text with a
+            new-line in it. Selector = 1.|[1,Inf]This is a text with a
+            new-line in it. Selector > 1.', 1),
+            array("This is a text with a\n            new-line in it. Selector > 1.", '{0}This is a text with a
+            new-line in it. Selector = 0.|{1}This is a text with a
+            new-line in it. Selector = 1.|[1,Inf]This is a text with a
+            new-line in it. Selector > 1.', 5),
+            // with double-quotes and id split accros lines
+            array('This is a text with a
+            new-line in it. Selector = 1.', '{0}This is a text with a
+            new-line in it. Selector = 0.|{1}This is a text with a
+            new-line in it. Selector = 1.|[1,Inf]This is a text with a
+            new-line in it. Selector > 1.', 1),
+            // with single-quotes and id split accros lines
+            array('This is a text with a
+            new-line in it. Selector > 1.', '{0}This is a text with a
+            new-line in it. Selector = 0.|{1}This is a text with a
+            new-line in it. Selector = 1.|[1,Inf]This is a text with a
+            new-line in it. Selector > 1.', 5),
+            // with single-quotes and \n in text
+            array('This is a text with a\nnew-line in it. Selector = 0.', '{0}This is a text with a\nnew-line in it. Selector = 0.|{1}This is a text with a\nnew-line in it. Selector = 1.|[1,Inf]This is a text with a\nnew-line in it. Selector > 1.', 0),
+            // with double-quotes and id split accros lines
+            array("This is a text with a\nnew-line in it. Selector = 1.", "{0}This is a text with a\nnew-line in it. Selector = 0.|{1}This is a text with a\nnew-line in it. Selector = 1.|[1,Inf]This is a text with a\nnew-line in it. Selector > 1.", 1),
+            // esacape pipe
+            array('This is a text with | in it. Selector = 0.', '{0}This is a text with || in it. Selector = 0.|{1}This is a text with || in it. Selector = 1.', 0),
+            // Empty plural set (2 plural forms) from a .PO file
+            array('', '|', 1),
+            // Empty plural set (3 plural forms) from a .PO file
+            array('', '||', 1),
+        );
+    }
 }
diff --git a/src/Symfony/Component/Translation/Tests/LoggingTranslatorTest.php b/src/Symfony/Component/Translation/Tests/LoggingTranslatorTest.php
index 022379e934..0e43cbecf4 100644
--- a/src/Symfony/Component/Translation/Tests/LoggingTranslatorTest.php
+++ b/src/Symfony/Component/Translation/Tests/LoggingTranslatorTest.php
@@ -21,17 +21,19 @@ class LoggingTranslatorTest extends TestCase
     public function testTransWithNoTranslationIsLogged()
     {
         $logger = $this->getMockBuilder('Psr\Log\LoggerInterface')->getMock();
-        $logger->expects($this->exactly(2))
+        $logger->expects($this->exactly(1))
             ->method('warning')
             ->with('Translation not found.')
         ;
 
         $translator = new Translator('ar');
         $loggableTranslator = new LoggingTranslator($translator, $logger);
-        $loggableTranslator->transChoice('some_message2', 10, array('%count%' => 10));
         $loggableTranslator->trans('bar');
     }
 
+    /**
+     * @group legacy
+     */
     public function testTransChoiceFallbackIsLogged()
     {
         $logger = $this->getMockBuilder('Psr\Log\LoggerInterface')->getMock();
@@ -47,4 +49,20 @@ class LoggingTranslatorTest extends TestCase
         $loggableTranslator = new LoggingTranslator($translator, $logger);
         $loggableTranslator->transChoice('some_message2', 10, array('%count%' => 10));
     }
+
+    /**
+     * @group legacy
+     */
+    public function testTransChoiceWithNoTranslationIsLogged()
+    {
+        $logger = $this->getMockBuilder('Psr\Log\LoggerInterface')->getMock();
+        $logger->expects($this->exactly(1))
+            ->method('warning')
+            ->with('Translation not found.')
+        ;
+
+        $translator = new Translator('ar');
+        $loggableTranslator = new LoggingTranslator($translator, $logger);
+        $loggableTranslator->transChoice('some_message2', 10, array('%count%' => 10));
+    }
 }
diff --git a/src/Symfony/Component/Translation/Tests/TranslatorTest.php b/src/Symfony/Component/Translation/Tests/TranslatorTest.php
index b0efefb7d0..c632d69041 100644
--- a/src/Symfony/Component/Translation/Tests/TranslatorTest.php
+++ b/src/Symfony/Component/Translation/Tests/TranslatorTest.php
@@ -393,6 +393,7 @@ class TranslatorTest extends TestCase
 
     /**
      * @dataProvider getTransChoiceTests
+     * @group legacy
      */
     public function testTransChoice($expected, $id, $translation, $number, $parameters, $locale, $domain)
     {
@@ -406,6 +407,7 @@ class TranslatorTest extends TestCase
     /**
      * @dataProvider      getInvalidLocalesTests
      * @expectedException \Symfony\Component\Translation\Exception\InvalidArgumentException
+     * @group legacy
      */
     public function testTransChoiceInvalidLocale($locale)
     {
@@ -418,6 +420,7 @@ class TranslatorTest extends TestCase
 
     /**
      * @dataProvider      getValidLocalesTests
+     * @group legacy
      */
     public function testTransChoiceValidLocale($locale)
     {
@@ -537,6 +540,9 @@ class TranslatorTest extends TestCase
         );
     }
 
+    /**
+     * @group legacy
+     */
     public function testTransChoiceFallback()
     {
         $translator = new Translator('ru');
@@ -547,6 +553,9 @@ class TranslatorTest extends TestCase
         $this->assertEquals('10 things', $translator->transChoice('some_message2', 10, array('%count%' => 10)));
     }
 
+    /**
+     * @group legacy
+     */
     public function testTransChoiceFallbackBis()
     {
         $translator = new Translator('ru');
@@ -557,6 +566,9 @@ class TranslatorTest extends TestCase
         $this->assertEquals('10 things', $translator->transChoice('some_message2', 10, array('%count%' => 10)));
     }
 
+    /**
+     * @group legacy
+     */
     public function testTransChoiceFallbackWithNoTranslation()
     {
         $translator = new Translator('ru');
diff --git a/src/Symfony/Component/Translation/Translator.php b/src/Symfony/Component/Translation/Translator.php
index b9a876497d..5670e613e3 100644
--- a/src/Symfony/Component/Translation/Translator.php
+++ b/src/Symfony/Component/Translation/Translator.php
@@ -202,6 +202,7 @@ class Translator implements TranslatorInterface, TranslatorBagInterface
      */
     public function transChoice($id, $number, array $parameters = array(), $domain = null, $locale = null)
     {
+        @trigger_error(sprintf('The "%s()" method is deprecated since Symfony 4.2, use the "trans()" method with intl formatted messages instead.', __METHOD__), E_USER_DEPRECATED);
         if (!$this->formatter instanceof ChoiceMessageFormatterInterface) {
             throw new LogicException(sprintf('The formatter "%s" does not support plural translations.', \get_class($this->formatter)));
         }
diff --git a/src/Symfony/Component/Translation/TranslatorInterface.php b/src/Symfony/Component/Translation/TranslatorInterface.php
index 829c6f3d14..2eea19866b 100644
--- a/src/Symfony/Component/Translation/TranslatorInterface.php
+++ b/src/Symfony/Component/Translation/TranslatorInterface.php
@@ -16,8 +16,54 @@ use Symfony\Contracts\Translation\TranslatorInterface as BaseTranslatorInterface
 /**
  * @author Fabien Potencier <fabien@symfony.com>
  *
- * @deprecated since Symfony 4.2, use the same interface from the Symfony\Contracts\Translation namespace
+ * @deprecated since Symfony 4.2, use the interface from the Symfony\Contracts\Translation namespace
  */
 interface TranslatorInterface extends BaseTranslatorInterface
 {
+    /**
+     * Translates the given choice message by choosing a translation according to a number.
+     *
+     * Given a message with different plural translations separated by a
+     * pipe (|), this method returns the correct portion of the message based
+     * on the given number, locale and the pluralization rules in the message
+     * itself.
+     *
+     * The message supports two different types of pluralization rules:
+     *
+     * interval: {0} There are no apples|{1} There is one apple|]1,Inf] There are %count% apples
+     * indexed:  There is one apple|There are %count% apples
+     *
+     * The indexed solution can also contain labels (e.g. one: There is one apple).
+     * This is purely for making the translations more clear - it does not
+     * affect the functionality.
+     *
+     * The two methods can also be mixed:
+     *     {0} There are no apples|one: There is one apple|more: There are %count% apples
+     *
+     * An interval can represent a finite set of numbers:
+     *  {1,2,3,4}
+     *
+     * An interval can represent numbers between two numbers:
+     *  [1, +Inf]
+     *  ]-1,2[
+     *
+     * The left delimiter can be [ (inclusive) or ] (exclusive).
+     * The right delimiter can be [ (exclusive) or ] (inclusive).
+     * Beside numbers, you can use -Inf and +Inf for the infinite.
+     *
+     * @see https://en.wikipedia.org/wiki/ISO_31-11
+     *
+     * @param string      $id         The message id (may also be an object that can be cast to string)
+     * @param int         $number     The number to use to find the indice of the message
+     * @param array       $parameters An array of parameters for the message
+     * @param string|null $domain     The domain for the message or null to use the default
+     * @param string|null $locale     The locale or null to use the default
+     *
+     * @return string The translated string
+     *
+     * @throws \InvalidArgumentException If the locale contains invalid characters
+     *
+     * @deprecated since Symfony 4.2
+     */
+    public function transChoice($id, $number, array $parameters = array(), $domain = null, $locale = null);
 }
diff --git a/src/Symfony/Component/Validator/Util/LegacyTranslatorProxy.php b/src/Symfony/Component/Validator/Util/LegacyTranslatorProxy.php
index 077d37931f..972c9bd931 100644
--- a/src/Symfony/Component/Validator/Util/LegacyTranslatorProxy.php
+++ b/src/Symfony/Component/Validator/Util/LegacyTranslatorProxy.php
@@ -11,6 +11,7 @@
 
 namespace Symfony\Component\Validator\Util;
 
+use Symfony\Component\Translation\LegacyTranslatorTrait;
 use Symfony\Component\Translation\TranslatorInterface as LegacyTranslatorInterface;
 use Symfony\Contracts\Translation\TranslatorInterface;
 
@@ -19,6 +20,9 @@ use Symfony\Contracts\Translation\TranslatorInterface;
  */
 class LegacyTranslatorProxy implements LegacyTranslatorInterface
 {
+    use LegacyTranslatorTrait {
+        transChoice as private doTransChoice;
+    }
     private $translator;
 
     public function __construct(TranslatorInterface $translator)
@@ -60,6 +64,10 @@ class LegacyTranslatorProxy implements LegacyTranslatorInterface
      */
     public function transChoice($id, $number, array $parameters = array(), $domain = null, $locale = null)
     {
-        return $this->translator->transChoice($id, $number, $parameters, $domain, $locale);
+        if ($this->translator instanceof LegacyTranslatorInterface) {
+            return $this->translator->transChoice($id, $number, $parameters, $domain, $locale);
+        }
+
+        $this->doTransChoice($id, $number, $parameters, $domain, $locale);
     }
 }
diff --git a/src/Symfony/Component/Validator/Violation/ConstraintViolationBuilder.php b/src/Symfony/Component/Validator/Violation/ConstraintViolationBuilder.php
index 621c38d9af..34b49f962a 100644
--- a/src/Symfony/Component/Validator/Violation/ConstraintViolationBuilder.php
+++ b/src/Symfony/Component/Validator/Violation/ConstraintViolationBuilder.php
@@ -11,6 +11,7 @@
 
 namespace Symfony\Component\Validator\Violation;
 
+use Symfony\Component\Translation\TranslatorInterface as LegacyTranslatorInterface;
 use Symfony\Component\Validator\Constraint;
 use Symfony\Component\Validator\ConstraintViolation;
 use Symfony\Component\Validator\ConstraintViolationList;
@@ -141,7 +142,7 @@ class ConstraintViolationBuilder implements ConstraintViolationBuilderInterface
      */
     public function addViolation()
     {
-        if (null === $this->plural) {
+        if (null === $this->plural || !$this->translator instanceof LegacyTranslatorInterface) {
             $translatedMessage = $this->translator->trans(
                 $this->message,
                 $this->parameters,
diff --git a/src/Symfony/Contracts/Tests/Translation/TranslatorTest.php b/src/Symfony/Contracts/Tests/Translation/TranslatorTest.php
index e7af8e4da3..a7642bfa11 100644
--- a/src/Symfony/Contracts/Tests/Translation/TranslatorTest.php
+++ b/src/Symfony/Contracts/Tests/Translation/TranslatorTest.php
@@ -47,29 +47,6 @@ class TranslatorTest extends TestCase
         $this->assertEquals($expected, $translator->trans($id, $parameters));
     }
 
-    /**
-     * @dataProvider getTransChoiceTests
-     */
-    public function testTransChoiceWithExplicitLocale($expected, $id, $number, $parameters)
-    {
-        $translator = $this->getTranslator();
-        $translator->setLocale('en');
-
-        $this->assertEquals($expected, $translator->transChoice($id, $number, $parameters));
-    }
-
-    /**
-     * @dataProvider getTransChoiceTests
-     */
-    public function testTransChoiceWithDefaultLocale($expected, $id, $number, $parameters)
-    {
-        \Locale::setDefault('en');
-
-        $translator = $this->getTranslator();
-
-        $this->assertEquals($expected, $translator->transChoice($id, $number, $parameters));
-    }
-
     public function testGetSetLocale()
     {
         $translator = $this->getTranslator();
@@ -99,255 +76,4 @@ class TranslatorTest extends TestCase
             array('Symfony is awesome!', 'Symfony is %what%!', array('%what%' => 'awesome')),
         );
     }
-
-    public function getTransChoiceTests()
-    {
-        return array(
-            array('There are no apples', '{0} There are no apples|{1} There is one apple|]1,Inf] There are %count% apples', 0, array('%count%' => 0)),
-            array('There is one apple', '{0} There are no apples|{1} There is one apple|]1,Inf] There are %count% apples', 1, array('%count%' => 1)),
-            array('There are 10 apples', '{0} There are no apples|{1} There is one apple|]1,Inf] There are %count% apples', 10, array('%count%' => 10)),
-            array('There are 0 apples', 'There is 1 apple|There are %count% apples', 0, array('%count%' => 0)),
-            array('There is 1 apple', 'There is 1 apple|There are %count% apples', 1, array('%count%' => 1)),
-            array('There are 10 apples', 'There is 1 apple|There are %count% apples', 10, array('%count%' => 10)),
-            // custom validation messages may be coded with a fixed value
-            array('There are 2 apples', 'There are 2 apples', 2, array('%count%' => 2)),
-        );
-    }
-
-    /**
-     * @dataProvider getInternal
-     */
-    public function testInterval($expected, $number, $interval)
-    {
-        $translator = $this->getTranslator();
-
-        $this->assertEquals($expected, $translator->transChoice($interval.' foo|[1,Inf[ bar', $number));
-    }
-
-    public function getInternal()
-    {
-        return array(
-            array('foo', 3, '{1,2, 3 ,4}'),
-            array('bar', 10, '{1,2, 3 ,4}'),
-            array('bar', 3, '[1,2]'),
-            array('foo', 1, '[1,2]'),
-            array('foo', 2, '[1,2]'),
-            array('bar', 1, ']1,2['),
-            array('bar', 2, ']1,2['),
-            array('foo', log(0), '[-Inf,2['),
-            array('foo', -log(0), '[-2,+Inf]'),
-        );
-    }
-
-    /**
-     * @dataProvider getChooseTests
-     */
-    public function testChoose($expected, $id, $number)
-    {
-        $translator = $this->getTranslator();
-
-        $this->assertEquals($expected, $translator->transChoice($id, $number));
-    }
-
-    public function testReturnMessageIfExactlyOneStandardRuleIsGiven()
-    {
-        $translator = $this->getTranslator();
-
-        $this->assertEquals('There are two apples', $translator->transChoice('There are two apples', 2));
-    }
-
-    /**
-     * @dataProvider getNonMatchingMessages
-     * @expectedException \InvalidArgumentException
-     */
-    public function testThrowExceptionIfMatchingMessageCannotBeFound($id, $number)
-    {
-        $translator = $this->getTranslator();
-
-        $translator->transChoice($id, $number);
-    }
-
-    public function getNonMatchingMessages()
-    {
-        return array(
-            array('{0} There are no apples|{1} There is one apple', 2),
-            array('{1} There is one apple|]1,Inf] There are %count% apples', 0),
-            array('{1} There is one apple|]2,Inf] There are %count% apples', 2),
-            array('{0} There are no apples|There is one apple', 2),
-        );
-    }
-
-    public function getChooseTests()
-    {
-        return array(
-            array('There are no apples', '{0} There are no apples|{1} There is one apple|]1,Inf] There are %count% apples', 0),
-            array('There are no apples', '{0}     There are no apples|{1} There is one apple|]1,Inf] There are %count% apples', 0),
-            array('There are no apples', '{0}There are no apples|{1} There is one apple|]1,Inf] There are %count% apples', 0),
-
-            array('There is one apple', '{0} There are no apples|{1} There is one apple|]1,Inf] There are %count% apples', 1),
-
-            array('There are %count% apples', '{0} There are no apples|{1} There is one apple|]1,Inf] There are %count% apples', 10),
-            array('There are %count% apples', '{0} There are no apples|{1} There is one apple|]1,Inf]There are %count% apples', 10),
-            array('There are %count% apples', '{0} There are no apples|{1} There is one apple|]1,Inf]     There are %count% apples', 10),
-
-            array('There are %count% apples', 'There is one apple|There are %count% apples', 0),
-            array('There is one apple', 'There is one apple|There are %count% apples', 1),
-            array('There are %count% apples', 'There is one apple|There are %count% apples', 10),
-
-            array('There are %count% apples', 'one: There is one apple|more: There are %count% apples', 0),
-            array('There is one apple', 'one: There is one apple|more: There are %count% apples', 1),
-            array('There are %count% apples', 'one: There is one apple|more: There are %count% apples', 10),
-
-            array('There are no apples', '{0} There are no apples|one: There is one apple|more: There are %count% apples', 0),
-            array('There is one apple', '{0} There are no apples|one: There is one apple|more: There are %count% apples', 1),
-            array('There are %count% apples', '{0} There are no apples|one: There is one apple|more: There are %count% apples', 10),
-
-            array('', '{0}|{1} There is one apple|]1,Inf] There are %count% apples', 0),
-            array('', '{0} There are no apples|{1}|]1,Inf] There are %count% apples', 1),
-
-            // Indexed only tests which are Gettext PoFile* compatible strings.
-            array('There are %count% apples', 'There is one apple|There are %count% apples', 0),
-            array('There is one apple', 'There is one apple|There are %count% apples', 1),
-            array('There are %count% apples', 'There is one apple|There are %count% apples', 2),
-
-            // Tests for float numbers
-            array('There is almost one apple', '{0} There are no apples|]0,1[ There is almost one apple|{1} There is one apple|[1,Inf] There is more than one apple', 0.7),
-            array('There is one apple', '{0} There are no apples|]0,1[There are %count% apples|{1} There is one apple|[1,Inf] There is more than one apple', 1),
-            array('There is more than one apple', '{0} There are no apples|]0,1[There are %count% apples|{1} There is one apple|[1,Inf] There is more than one apple', 1.7),
-            array('There are no apples', '{0} There are no apples|]0,1[There are %count% apples|{1} There is one apple|[1,Inf] There is more than one apple', 0),
-            array('There are no apples', '{0} There are no apples|]0,1[There are %count% apples|{1} There is one apple|[1,Inf] There is more than one apple', 0.0),
-            array('There are no apples', '{0.0} There are no apples|]0,1[There are %count% apples|{1} There is one apple|[1,Inf] There is more than one apple', 0),
-
-            // Test texts with new-lines
-            // with double-quotes and \n in id & double-quotes and actual newlines in text
-            array("This is a text with a\n            new-line in it. Selector = 0.", '{0}This is a text with a
-            new-line in it. Selector = 0.|{1}This is a text with a
-            new-line in it. Selector = 1.|[1,Inf]This is a text with a
-            new-line in it. Selector > 1.', 0),
-            // with double-quotes and \n in id and single-quotes and actual newlines in text
-            array("This is a text with a\n            new-line in it. Selector = 1.", '{0}This is a text with a
-            new-line in it. Selector = 0.|{1}This is a text with a
-            new-line in it. Selector = 1.|[1,Inf]This is a text with a
-            new-line in it. Selector > 1.', 1),
-            array("This is a text with a\n            new-line in it. Selector > 1.", '{0}This is a text with a
-            new-line in it. Selector = 0.|{1}This is a text with a
-            new-line in it. Selector = 1.|[1,Inf]This is a text with a
-            new-line in it. Selector > 1.', 5),
-            // with double-quotes and id split accros lines
-            array('This is a text with a
-            new-line in it. Selector = 1.', '{0}This is a text with a
-            new-line in it. Selector = 0.|{1}This is a text with a
-            new-line in it. Selector = 1.|[1,Inf]This is a text with a
-            new-line in it. Selector > 1.', 1),
-            // with single-quotes and id split accros lines
-            array('This is a text with a
-            new-line in it. Selector > 1.', '{0}This is a text with a
-            new-line in it. Selector = 0.|{1}This is a text with a
-            new-line in it. Selector = 1.|[1,Inf]This is a text with a
-            new-line in it. Selector > 1.', 5),
-            // with single-quotes and \n in text
-            array('This is a text with a\nnew-line in it. Selector = 0.', '{0}This is a text with a\nnew-line in it. Selector = 0.|{1}This is a text with a\nnew-line in it. Selector = 1.|[1,Inf]This is a text with a\nnew-line in it. Selector > 1.', 0),
-            // with double-quotes and id split accros lines
-            array("This is a text with a\nnew-line in it. Selector = 1.", "{0}This is a text with a\nnew-line in it. Selector = 0.|{1}This is a text with a\nnew-line in it. Selector = 1.|[1,Inf]This is a text with a\nnew-line in it. Selector > 1.", 1),
-            // esacape pipe
-            array('This is a text with | in it. Selector = 0.', '{0}This is a text with || in it. Selector = 0.|{1}This is a text with || in it. Selector = 1.', 0),
-            // Empty plural set (2 plural forms) from a .PO file
-            array('', '|', 1),
-            // Empty plural set (3 plural forms) from a .PO file
-            array('', '||', 1),
-        );
-    }
-
-    /**
-     * @dataProvider failingLangcodes
-     */
-    public function testFailedLangcodes($nplural, $langCodes)
-    {
-        $matrix = $this->generateTestData($langCodes);
-        $this->validateMatrix($nplural, $matrix, false);
-    }
-
-    /**
-     * @dataProvider successLangcodes
-     */
-    public function testLangcodes($nplural, $langCodes)
-    {
-        $matrix = $this->generateTestData($langCodes);
-        $this->validateMatrix($nplural, $matrix);
-    }
-
-    /**
-     * This array should contain all currently known langcodes.
-     *
-     * As it is impossible to have this ever complete we should try as hard as possible to have it almost complete.
-     *
-     * @return array
-     */
-    public function successLangcodes()
-    {
-        return array(
-            array('1', array('ay', 'bo', 'cgg', 'dz', 'id', 'ja', 'jbo', 'ka', 'kk', 'km', 'ko', 'ky')),
-            array('2', array('nl', 'fr', 'en', 'de', 'de_GE', 'hy', 'hy_AM')),
-            array('3', array('be', 'bs', 'cs', 'hr')),
-            array('4', array('cy', 'mt', 'sl')),
-            array('6', array('ar')),
-        );
-    }
-
-    /**
-     * This array should be at least empty within the near future.
-     *
-     * This both depends on a complete list trying to add above as understanding
-     * the plural rules of the current failing languages.
-     *
-     * @return array with nplural together with langcodes
-     */
-    public function failingLangcodes()
-    {
-        return array(
-            array('1', array('fa')),
-            array('2', array('jbo')),
-            array('3', array('cbs')),
-            array('4', array('gd', 'kw')),
-            array('5', array('ga')),
-        );
-    }
-
-    /**
-     * We validate only on the plural coverage. Thus the real rules is not tested.
-     *
-     * @param string $nplural       Plural expected
-     * @param array  $matrix        Containing langcodes and their plural index values
-     * @param bool   $expectSuccess
-     */
-    protected function validateMatrix($nplural, $matrix, $expectSuccess = true)
-    {
-        foreach ($matrix as $langCode => $data) {
-            $indexes = array_flip($data);
-            if ($expectSuccess) {
-                $this->assertEquals($nplural, \count($indexes), "Langcode '$langCode' has '$nplural' plural forms.");
-            } else {
-                $this->assertNotEquals((int) $nplural, \count($indexes), "Langcode '$langCode' has '$nplural' plural forms.");
-            }
-        }
-    }
-
-    protected function generateTestData($langCodes)
-    {
-        $translator = new class() {
-            use TranslatorTrait {
-                getPluralizationRule as public;
-            }
-        };
-
-        $matrix = array();
-        foreach ($langCodes as $langCode) {
-            for ($count = 0; $count < 200; ++$count) {
-                $plural = $translator->getPluralizationRule($count, $langCode);
-                $matrix[$langCode][$count] = $plural;
-            }
-        }
-
-        return $matrix;
-    }
 }
diff --git a/src/Symfony/Contracts/Translation/TranslatorInterface.php b/src/Symfony/Contracts/Translation/TranslatorInterface.php
index a54718733b..7620fd3787 100644
--- a/src/Symfony/Contracts/Translation/TranslatorInterface.php
+++ b/src/Symfony/Contracts/Translation/TranslatorInterface.php
@@ -30,51 +30,6 @@ interface TranslatorInterface
      */
     public function trans($id, array $parameters = array(), $domain = null, $locale = null);
 
-    /**
-     * Translates the given choice message by choosing a translation according to a number.
-     *
-     * Given a message with different plural translations separated by a
-     * pipe (|), this method returns the correct portion of the message based
-     * on the given number, locale and the pluralization rules in the message
-     * itself.
-     *
-     * The message supports two different types of pluralization rules:
-     *
-     * interval: {0} There are no apples|{1} There is one apple|]1,Inf] There are %count% apples
-     * indexed:  There is one apple|There are %count% apples
-     *
-     * The indexed solution can also contain labels (e.g. one: There is one apple).
-     * This is purely for making the translations more clear - it does not
-     * affect the functionality.
-     *
-     * The two methods can also be mixed:
-     *     {0} There are no apples|one: There is one apple|more: There are %count% apples
-     *
-     * An interval can represent a finite set of numbers:
-     *  {1,2,3,4}
-     *
-     * An interval can represent numbers between two numbers:
-     *  [1, +Inf]
-     *  ]-1,2[
-     *
-     * The left delimiter can be [ (inclusive) or ] (exclusive).
-     * The right delimiter can be [ (exclusive) or ] (inclusive).
-     * Beside numbers, you can use -Inf and +Inf for the infinite.
-     *
-     * @see https://en.wikipedia.org/wiki/ISO_31-11
-     *
-     * @param string      $id         The message id (may also be an object that can be cast to string)
-     * @param int         $number     The number to use to find the indice of the message
-     * @param array       $parameters An array of parameters for the message
-     * @param string|null $domain     The domain for the message or null to use the default
-     * @param string|null $locale     The locale or null to use the default
-     *
-     * @return string The translated string
-     *
-     * @throws \InvalidArgumentException If the locale contains invalid characters
-     */
-    public function transChoice($id, $number, array $parameters = array(), $domain = null, $locale = null);
-
     /**
      * Sets the current locale.
      *
diff --git a/src/Symfony/Contracts/Translation/TranslatorTrait.php b/src/Symfony/Contracts/Translation/TranslatorTrait.php
index 7c392b2bd4..b92105f190 100644
--- a/src/Symfony/Contracts/Translation/TranslatorTrait.php
+++ b/src/Symfony/Contracts/Translation/TranslatorTrait.php
@@ -11,8 +11,6 @@
 
 namespace Symfony\Contracts\Translation;
 
-use Symfony\Component\Translation\Exception\InvalidArgumentException;
-
 /**
  * A trait to help implement TranslatorInterface.
  *
@@ -45,214 +43,4 @@ trait TranslatorTrait
     {
         return strtr((string) $id, $parameters);
     }
-
-    /**
-     * {@inheritdoc}
-     */
-    public function transChoice($id, $number, array $parameters = array(), $domain = null, $locale = null)
-    {
-        $id = (string) $id;
-        $number = (float) $number;
-        $locale = (string) $locale ?: $this->getLocale();
-
-        $parts = array();
-        if (preg_match('/^\|++$/', $id)) {
-            $parts = explode('|', $id);
-        } elseif (preg_match_all('/(?:\|\||[^\|])++/', $id, $matches)) {
-            $parts = $matches[0];
-        }
-
-        $intervalRegexp = <<<'EOF'
-/^(?P<interval>
-    ({\s*
-        (\-?\d+(\.\d+)?[\s*,\s*\-?\d+(\.\d+)?]*)
-    \s*})
-
-        |
-
-    (?P<left_delimiter>[\[\]])
-        \s*
-        (?P<left>-Inf|\-?\d+(\.\d+)?)
-        \s*,\s*
-        (?P<right>\+?Inf|\-?\d+(\.\d+)?)
-        \s*
-    (?P<right_delimiter>[\[\]])
-)\s*(?P<message>.*?)$/xs
-EOF;
-
-        $standardRules = array();
-        foreach ($parts as $part) {
-            $part = trim(str_replace('||', '|', $part));
-
-            // try to match an explicit rule, then fallback to the standard ones
-            if (preg_match($intervalRegexp, $part, $matches)) {
-                if ($matches[2]) {
-                    foreach (explode(',', $matches[3]) as $n) {
-                        if ($number == $n) {
-                            return strtr($matches['message'], $parameters);
-                        }
-                    }
-                } else {
-                    $leftNumber = '-Inf' === $matches['left'] ? -INF : (float) $matches['left'];
-                    $rightNumber = \is_numeric($matches['right']) ? (float) $matches['right'] : INF;
-
-                    if (('[' === $matches['left_delimiter'] ? $number >= $leftNumber : $number > $leftNumber)
-                        && (']' === $matches['right_delimiter'] ? $number <= $rightNumber : $number < $rightNumber)
-                    ) {
-                        return strtr($matches['message'], $parameters);
-                    }
-                }
-            } elseif (preg_match('/^\w+\:\s*(.*?)$/', $part, $matches)) {
-                $standardRules[] = $matches[1];
-            } else {
-                $standardRules[] = $part;
-            }
-        }
-
-        $position = $this->getPluralizationRule($number, $locale);
-
-        if (!isset($standardRules[$position])) {
-            // when there's exactly one rule given, and that rule is a standard
-            // rule, use this rule
-            if (1 === \count($parts) && isset($standardRules[0])) {
-                return strtr($standardRules[0], $parameters);
-            }
-
-            $message = sprintf('Unable to choose a translation for "%s" with locale "%s" for value "%d". Double check that this translation has the correct plural options (e.g. "There is one apple|There are %%count%% apples").', $id, $locale, $number);
-
-            if (\class_exists(InvalidArgumentException::class)) {
-                throw new InvalidArgumentException($message);
-            }
-
-            throw new \InvalidArgumentException($message);
-        }
-
-        return strtr($standardRules[$position], $parameters);
-    }
-
-    /**
-     * Returns the plural position to use for the given locale and number.
-     *
-     * The plural rules are derived from code of the Zend Framework (2010-09-25),
-     * which is subject to the new BSD license (http://framework.zend.com/license/new-bsd).
-     * Copyright (c) 2005-2010 Zend Technologies USA Inc. (http://www.zend.com)
-     */
-    private function getPluralizationRule(int $number, string $locale): int
-    {
-        switch ('pt_BR' !== $locale && \strlen($locale) > 3 ? substr($locale, 0, strrpos($locale, '_')) : $locale) {
-            case 'af':
-            case 'bn':
-            case 'bg':
-            case 'ca':
-            case 'da':
-            case 'de':
-            case 'el':
-            case 'en':
-            case 'eo':
-            case 'es':
-            case 'et':
-            case 'eu':
-            case 'fa':
-            case 'fi':
-            case 'fo':
-            case 'fur':
-            case 'fy':
-            case 'gl':
-            case 'gu':
-            case 'ha':
-            case 'he':
-            case 'hu':
-            case 'is':
-            case 'it':
-            case 'ku':
-            case 'lb':
-            case 'ml':
-            case 'mn':
-            case 'mr':
-            case 'nah':
-            case 'nb':
-            case 'ne':
-            case 'nl':
-            case 'nn':
-            case 'no':
-            case 'oc':
-            case 'om':
-            case 'or':
-            case 'pa':
-            case 'pap':
-            case 'ps':
-            case 'pt':
-            case 'so':
-            case 'sq':
-            case 'sv':
-            case 'sw':
-            case 'ta':
-            case 'te':
-            case 'tk':
-            case 'ur':
-            case 'zu':
-                return (1 == $number) ? 0 : 1;
-
-            case 'am':
-            case 'bh':
-            case 'fil':
-            case 'fr':
-            case 'gun':
-            case 'hi':
-            case 'hy':
-            case 'ln':
-            case 'mg':
-            case 'nso':
-            case 'pt_BR':
-            case 'ti':
-            case 'wa':
-                return ((0 == $number) || (1 == $number)) ? 0 : 1;
-
-            case 'be':
-            case 'bs':
-            case 'hr':
-            case 'ru':
-            case 'sh':
-            case 'sr':
-            case 'uk':
-                return ((1 == $number % 10) && (11 != $number % 100)) ? 0 : ((($number % 10 >= 2) && ($number % 10 <= 4) && (($number % 100 < 10) || ($number % 100 >= 20))) ? 1 : 2);
-
-            case 'cs':
-            case 'sk':
-                return (1 == $number) ? 0 : ((($number >= 2) && ($number <= 4)) ? 1 : 2);
-
-            case 'ga':
-                return (1 == $number) ? 0 : ((2 == $number) ? 1 : 2);
-
-            case 'lt':
-                return ((1 == $number % 10) && (11 != $number % 100)) ? 0 : ((($number % 10 >= 2) && (($number % 100 < 10) || ($number % 100 >= 20))) ? 1 : 2);
-
-            case 'sl':
-                return (1 == $number % 100) ? 0 : ((2 == $number % 100) ? 1 : (((3 == $number % 100) || (4 == $number % 100)) ? 2 : 3));
-
-            case 'mk':
-                return (1 == $number % 10) ? 0 : 1;
-
-            case 'mt':
-                return (1 == $number) ? 0 : (((0 == $number) || (($number % 100 > 1) && ($number % 100 < 11))) ? 1 : ((($number % 100 > 10) && ($number % 100 < 20)) ? 2 : 3));
-
-            case 'lv':
-                return (0 == $number) ? 0 : (((1 == $number % 10) && (11 != $number % 100)) ? 1 : 2);
-
-            case 'pl':
-                return (1 == $number) ? 0 : ((($number % 10 >= 2) && ($number % 10 <= 4) && (($number % 100 < 12) || ($number % 100 > 14))) ? 1 : 2);
-
-            case 'cy':
-                return (1 == $number) ? 0 : ((2 == $number) ? 1 : (((8 == $number) || (11 == $number)) ? 2 : 3));
-
-            case 'ro':
-                return (1 == $number) ? 0 : (((0 == $number) || (($number % 100 > 0) && ($number % 100 < 20))) ? 1 : 2);
-
-            case 'ar':
-                return (0 == $number) ? 0 : ((1 == $number) ? 1 : ((2 == $number) ? 2 : ((($number % 100 >= 3) && ($number % 100 <= 10)) ? 3 : ((($number % 100 >= 11) && ($number % 100 <= 99)) ? 4 : 5))));
-
-            default:
-                return 0;
-        }
-    }
 }

From dc5f3bfff7b83eb95fcbd150b99e87c010014f5b Mon Sep 17 00:00:00 2001
From: Nicolas Grekas <nicolas.grekas@gmail.com>
Date: Mon, 1 Oct 2018 13:27:53 +0200
Subject: [PATCH 2/2] Make trans + %count% parameter resolve plurals

---
 UPGRADE-4.2.md                                |   8 +-
 UPGRADE-5.0.md                                |   3 +
 src/Symfony/Bridge/Twig/CHANGELOG.md          |   5 +-
 .../Twig/Extension/TranslationExtension.php   |  37 ++-
 src/Symfony/Bridge/Twig/Node/TransNode.php    |  19 +-
 .../Extension/TranslationExtensionTest.php    |  85 +++++-
 .../Bridge/Twig/Tests/Node/TransNodeTest.php  |   2 +-
 .../Tests/Translation/TwigExtractorTest.php   |  30 +-
 .../TokenParser/TransChoiceTokenParser.php    |   4 +
 .../Twig/TokenParser/TransTokenParser.php     |   9 +-
 .../Bundle/FrameworkBundle/CHANGELOG.md       |   1 +
 .../Command/TranslationDebugCommand.php       |   9 +-
 .../Templating/Helper/TranslatorHelper.php    |  23 +-
 .../Tests/Translation/TranslatorTest.php      |   4 +
 .../Form/Extension/Csrf/CsrfExtension.php     |   8 +-
 .../EventListener/CsrfValidationListener.php  |   9 +-
 .../Csrf/Type/FormTypeCsrfExtension.php       |   9 +-
 .../Type/UploadValidatorExtension.php         |   9 +-
 .../EventListener/TranslatorListener.php      |   9 +-
 .../Component/Translation/CHANGELOG.md        |   2 +-
 .../Translation/DataCollectorTranslator.php   |  28 +-
 .../ChoiceMessageFormatterInterface.php       |   2 +
 .../Formatter/MessageFormatter.php            |  17 +-
 .../Translation/IdentityTranslator.php        |  19 +-
 .../Translation/LegacyTranslatorTrait.php     | 110 -------
 .../Translation/LoggingTranslator.php         |  19 +-
 .../Tests/DataCollectorTranslatorTest.php     |  12 +-
 .../Tests/IdentityTranslatorTest.php          | 189 ------------
 .../Translation/Tests/TranslatorTest.php      |   2 +-
 .../Component/Translation/Translator.php      |   9 +-
 .../Translation/TranslatorInterface.php       |  72 ++---
 .../Validator/Context/ExecutionContext.php    |   6 +-
 .../Context/ExecutionContextFactory.php       |   7 +-
 .../Validator/Util/LegacyTranslatorProxy.php  |  12 +-
 .../Violation/ConstraintViolationBuilder.php  |  16 +-
 .../Tests/Translation/TranslatorTest.php      | 274 ++++++++++++++++++
 .../Translation/TranslatorInterface.php       |  33 +++
 .../Contracts/Translation/TranslatorTrait.php | 211 +++++++++++++-
 38 files changed, 890 insertions(+), 433 deletions(-)
 delete mode 100644 src/Symfony/Component/Translation/LegacyTranslatorTrait.php

diff --git a/UPGRADE-4.2.md b/UPGRADE-4.2.md
index 95f2b980c8..6b3c4423d1 100644
--- a/UPGRADE-4.2.md
+++ b/UPGRADE-4.2.md
@@ -114,6 +114,7 @@ FrameworkBundle
    set the "APP_ENV" environment variable instead.
  * The `--no-debug` console option has been deprecated,
    set the "APP_DEBUG" environment variable to "0" instead.
+ * The `Templating\Helper\TranslatorHelper::transChoice()` method has been deprecated, use the `trans()` one instead with a `%count%` parameter.
 
 Messenger
 ---------
@@ -219,10 +220,15 @@ Translation
 -----------
 
  * The `TranslatorInterface` has been deprecated in favor of `Symfony\Contracts\Translation\TranslatorInterface`
- * The `Translator::transChoice()` has been deprecated in favor of using `Translator::trans()` with intl message format
+ * The `Translator::transChoice()` method has been deprecated in favor of using `Translator::trans()` with "%count%" as the parameter driving plurals
  * The `MessageSelector`, `Interval` and `PluralizationRules` classes have been deprecated, use `IdentityTranslator` instead
  * The `Translator::getFallbackLocales()` and `TranslationDataCollector::getFallbackLocales()` method have been marked as internal
 
+TwigBundle
+----------
+
+ * The `transchoice` tag and filter have been deprecated, use the `trans` ones instead with a `%count%` parameter.
+
 Validator
 ---------
 
diff --git a/UPGRADE-5.0.md b/UPGRADE-5.0.md
index e7470a2467..a876f151b9 100644
--- a/UPGRADE-5.0.md
+++ b/UPGRADE-5.0.md
@@ -120,6 +120,7 @@ FrameworkBundle
    set the "APP_ENV" environment variable instead.
  * The `--no-debug` console option has been removed, 
    set the "APP_DEBUG" environment variable to "0" instead.
+ * The `Templating\Helper\TranslatorHelper::transChoice()` method has been removed, use the `trans()` one instead with a `%count%` parameter.
 
 HttpFoundation
 --------------
@@ -196,11 +197,13 @@ Translation
  * The `TranslatorInterface` has been removed in favor of `Symfony\Contracts\Translation\TranslatorInterface`
  * The `MessageSelector`, `Interval` and `PluralizationRules` classes have been removed, use `IdentityTranslator` instead
  * The `Translator::getFallbackLocales()` and `TranslationDataCollector::getFallbackLocales()` method are now internal
+ * The `Translator::transChoice()` method has been removed in favor of using `Translator::trans()` with "%count%" as the parameter driving plurals
 
 TwigBundle
 ----------
 
  * The default value (`false`) of the `twig.strict_variables` configuration option has been changed to `%kernel.debug%`.
+ * The `transchoice` tag and filter have been removed, use the `trans` ones instead with a `%count%` parameter.
 
 Validator
 --------
diff --git a/src/Symfony/Bridge/Twig/CHANGELOG.md b/src/Symfony/Bridge/Twig/CHANGELOG.md
index a2e55f6db2..341bcfa538 100644
--- a/src/Symfony/Bridge/Twig/CHANGELOG.md
+++ b/src/Symfony/Bridge/Twig/CHANGELOG.md
@@ -4,8 +4,9 @@ CHANGELOG
 4.2.0
 -----
 
-* add bundle name suggestion on wrongly overridden templates paths
-* added `name` argument in `debug:twig` command and changed `filter` argument as `--filter` option
+ * add bundle name suggestion on wrongly overridden templates paths
+ * added `name` argument in `debug:twig` command and changed `filter` argument as `--filter` option
+ * deprecated the `transchoice` tag and filter, use the `trans` ones instead with a `%count%` parameter
 
 4.1.0
 -----
diff --git a/src/Symfony/Bridge/Twig/Extension/TranslationExtension.php b/src/Symfony/Bridge/Twig/Extension/TranslationExtension.php
index 090aed5548..ec5d452cef 100644
--- a/src/Symfony/Bridge/Twig/Extension/TranslationExtension.php
+++ b/src/Symfony/Bridge/Twig/Extension/TranslationExtension.php
@@ -16,7 +16,6 @@ use Symfony\Bridge\Twig\NodeVisitor\TranslationNodeVisitor;
 use Symfony\Bridge\Twig\TokenParser\TransChoiceTokenParser;
 use Symfony\Bridge\Twig\TokenParser\TransDefaultDomainTokenParser;
 use Symfony\Bridge\Twig\TokenParser\TransTokenParser;
-use Symfony\Component\Translation\LegacyTranslatorTrait;
 use Symfony\Component\Translation\TranslatorInterface as LegacyTranslatorInterface;
 use Symfony\Contracts\Translation\TranslatorInterface;
 use Symfony\Contracts\Translation\TranslatorTrait;
@@ -29,6 +28,8 @@ use Twig\TwigFilter;
  * Provides integration of the Translation component with Twig.
  *
  * @author Fabien Potencier <fabien@symfony.com>
+ *
+ * @final since Symfony 4.2
  */
 class TranslationExtension extends AbstractExtension
 {
@@ -38,21 +39,28 @@ class TranslationExtension extends AbstractExtension
         trans as private doTrans;
     }
 
-    use LegacyTranslatorTrait {
-        transChoice as private doTransChoice;
-    }
-
     private $translator;
     private $translationNodeVisitor;
 
-    public function __construct(TranslatorInterface $translator = null, NodeVisitorInterface $translationNodeVisitor = null)
+    /**
+     * @param TranslatorInterface|null $translator
+     */
+    public function __construct($translator = null, NodeVisitorInterface $translationNodeVisitor = null)
     {
+        if (null !== $translator && !$translator instanceof LegacyTranslatorInterface && !$translator instanceof TranslatorInterface) {
+            throw new \TypeError(sprintf('Argument 1 passed to %s() must be an instance of %s, %s given.', __METHOD__, TranslatorInterface::class, \is_object($translator) ? \get_class($translator) : \gettype($translator)));
+        }
         $this->translator = $translator;
         $this->translationNodeVisitor = $translationNodeVisitor;
     }
 
+    /**
+     * @deprecated since Symfony 4.2
+     */
     public function getTranslator()
     {
+        @trigger_error(sprintf('The "%s()" method is deprecated since Symfony 4.2.', __METHOD__), E_USER_DEPRECATED);
+
         return $this->translator;
     }
 
@@ -63,7 +71,7 @@ class TranslationExtension extends AbstractExtension
     {
         return array(
             new TwigFilter('trans', array($this, 'trans')),
-            new TwigFilter('transchoice', array($this, 'transchoice')),
+            new TwigFilter('transchoice', array($this, 'transchoice'), array('deprecated' => '4.2', 'alternative' => 'trans" with parameter "%count%')),
         );
     }
 
@@ -101,8 +109,11 @@ class TranslationExtension extends AbstractExtension
         return $this->translationNodeVisitor ?: $this->translationNodeVisitor = new TranslationNodeVisitor();
     }
 
-    public function trans($message, array $arguments = array(), $domain = null, $locale = null)
+    public function trans($message, array $arguments = array(), $domain = null, $locale = null, $count = null)
     {
+        if (null !== $count) {
+            $arguments['%count%'] = $count;
+        }
         if (null === $this->translator) {
             return $this->doTrans($message, $arguments, $domain, $locale);
         }
@@ -110,10 +121,16 @@ class TranslationExtension extends AbstractExtension
         return $this->translator->trans($message, $arguments, $domain, $locale);
     }
 
+    /**
+     * @deprecated since Symfony 4.2, use the trans() method instead with a %count% parameter
+     */
     public function transchoice($message, $count, array $arguments = array(), $domain = null, $locale = null)
     {
-        if (null === $this->translator || !$this->translator instanceof LegacyTranslatorInterface) {
-            return $this->doTransChoice($message, $count, array_merge(array('%count%' => $count), $arguments), $domain, $locale);
+        if (null === $this->translator) {
+            return $this->doTrans($message, array_merge(array('%count%' => $count), $arguments), $domain, $locale);
+        }
+        if ($this->translator instanceof TranslatorInterface) {
+            return $this->translator->trans($message, array_merge(array('%count%' => $count), $arguments), $domain, $locale);
         }
 
         return $this->translator->transChoice($message, $count, array_merge(array('%count%' => $count), $arguments), $domain, $locale);
diff --git a/src/Symfony/Bridge/Twig/Node/TransNode.php b/src/Symfony/Bridge/Twig/Node/TransNode.php
index 7eb8d743e9..578e37dd2c 100644
--- a/src/Symfony/Bridge/Twig/Node/TransNode.php
+++ b/src/Symfony/Bridge/Twig/Node/TransNode.php
@@ -60,19 +60,12 @@ class TransNode extends Node
         $method = !$this->hasNode('count') ? 'trans' : 'transChoice';
 
         $compiler
-            ->write('echo $this->env->getExtension(\'Symfony\Bridge\Twig\Extension\TranslationExtension\')->getTranslator()->'.$method.'(')
+            ->write('echo $this->env->getExtension(\'Symfony\Bridge\Twig\Extension\TranslationExtension\')->trans(')
             ->subcompile($msg)
         ;
 
         $compiler->raw(', ');
 
-        if ($this->hasNode('count')) {
-            $compiler
-                ->subcompile($this->getNode('count'))
-                ->raw(', ')
-            ;
-        }
-
         if (null !== $vars) {
             $compiler
                 ->raw('array_merge(')
@@ -98,7 +91,17 @@ class TransNode extends Node
                 ->raw(', ')
                 ->subcompile($this->getNode('locale'))
             ;
+        } elseif ($this->hasNode('count')) {
+            $compiler->raw(', null');
         }
+
+        if ($this->hasNode('count')) {
+            $compiler
+                ->raw(', ')
+                ->subcompile($this->getNode('count'))
+            ;
+        }
+
         $compiler->raw(");\n");
     }
 
diff --git a/src/Symfony/Bridge/Twig/Tests/Extension/TranslationExtensionTest.php b/src/Symfony/Bridge/Twig/Tests/Extension/TranslationExtensionTest.php
index feba2b2b6b..bb36cda8ea 100644
--- a/src/Symfony/Bridge/Twig/Tests/Extension/TranslationExtensionTest.php
+++ b/src/Symfony/Bridge/Twig/Tests/Extension/TranslationExtensionTest.php
@@ -45,6 +45,15 @@ class TranslationExtensionTest extends TestCase
         $this->assertEquals($expected, $this->getTemplate($template)->render($variables));
     }
 
+    /**
+     * @group legacy
+     * @dataProvider getTransChoiceTests
+     */
+    public function testTransChoice($template, $expected, array $variables = array())
+    {
+        $this->testTrans($template, $expected, $variables);
+    }
+
     /**
      * @expectedException        \Twig\Error\SyntaxError
      * @expectedExceptionMessage Unexpected token. Twig was looking for the "with", "from", or "into" keyword in "index" at line 3.
@@ -64,6 +73,7 @@ class TranslationExtensionTest extends TestCase
     }
 
     /**
+     * @group legacy
      * @expectedException        \Twig\Error\SyntaxError
      * @expectedExceptionMessage A message inside a transchoice tag must be a simple text in "index" at line 2.
      */
@@ -87,6 +97,69 @@ class TranslationExtensionTest extends TestCase
 
             array('{% trans into "fr"%}Hello{% endtrans %}', 'Hello'),
 
+            // trans with count
+            array(
+                '{% trans from "messages" %}{0} There is no apples|{1} There is one apple|]1,Inf] There is %count% apples{% endtrans %}',
+                'There is no apples',
+                array('count' => 0),
+            ),
+            array(
+                '{% trans %}{0} There is no apples|{1} There is one apple|]1,Inf] There is %count% apples{% endtrans %}',
+                'There is 5 apples',
+                array('count' => 5),
+            ),
+            array(
+                '{% trans %}{0} There is no apples|{1} There is one apple|]1,Inf] There is %count% apples (%name%){% endtrans %}',
+                'There is 5 apples (Symfony)',
+                array('count' => 5, 'name' => 'Symfony'),
+            ),
+            array(
+                '{% trans with { \'%name%\': \'Symfony\' } %}{0} There is no apples|{1} There is one apple|]1,Inf] There is %count% apples (%name%){% endtrans %}',
+                'There is 5 apples (Symfony)',
+                array('count' => 5),
+            ),
+            array(
+                '{% trans into "fr"%}{0} There is no apples|{1} There is one apple|]1,Inf] There is %count% apples{% endtrans %}',
+                'There is no apples',
+                array('count' => 0),
+            ),
+            array(
+                '{% trans count 5 into "fr"%}{0} There is no apples|{1} There is one apple|]1,Inf] There is %count% apples{% endtrans %}',
+                'There is 5 apples',
+            ),
+
+            // trans filter
+            array('{{ "Hello"|trans }}', 'Hello'),
+            array('{{ name|trans }}', 'Symfony', array('name' => 'Symfony')),
+            array('{{ hello|trans({ \'%name%\': \'Symfony\' }) }}', 'Hello Symfony', array('hello' => 'Hello %name%')),
+            array('{% set vars = { \'%name%\': \'Symfony\' } %}{{ hello|trans(vars) }}', 'Hello Symfony', array('hello' => 'Hello %name%')),
+            array('{{ "Hello"|trans({}, "messages", "fr") }}', 'Hello'),
+
+            // trans filter with count
+            array('{{ "{0} There is no apples|{1} There is one apple|]1,Inf] There is %count% apples"|trans(count=count) }}', 'There is 5 apples', array('count' => 5)),
+            array('{{ text|trans(count=5, arguments={\'%name%\': \'Symfony\'}) }}', 'There is 5 apples (Symfony)', array('text' => '{0} There is no apples|{1} There is one apple|]1,Inf] There is %count% apples (%name%)')),
+            array('{{ "{0} There is no apples|{1} There is one apple|]1,Inf] There is %count% apples"|trans({}, "messages", "fr", count) }}', 'There is 5 apples', array('count' => 5)),
+        );
+    }
+
+    /**
+     * @group legacy
+     */
+    public function getTransChoiceTests()
+    {
+        return array(
+            // trans tag
+            array('{% trans %}Hello{% endtrans %}', 'Hello'),
+            array('{% trans %}%name%{% endtrans %}', 'Symfony', array('name' => 'Symfony')),
+
+            array('{% trans from elsewhere %}Hello{% endtrans %}', 'Hello'),
+
+            array('{% trans %}Hello %name%{% endtrans %}', 'Hello Symfony', array('name' => 'Symfony')),
+            array('{% trans with { \'%name%\': \'Symfony\' } %}Hello %name%{% endtrans %}', 'Hello Symfony'),
+            array('{% set vars = { \'%name%\': \'Symfony\' } %}{% trans with vars %}Hello %name%{% endtrans %}', 'Hello Symfony'),
+
+            array('{% trans into "fr"%}Hello{% endtrans %}', 'Hello'),
+
             // transchoice
             array(
                 '{% transchoice count from "messages" %}{0} There is no apples|{1} There is one apple|]1,Inf] There is %count% apples{% endtranschoice %}',
@@ -145,8 +218,8 @@ class TranslationExtensionTest extends TestCase
                     {%- trans from "custom" %}foo{% endtrans %}
                     {{- "foo"|trans }}
                     {{- "foo"|trans({}, "custom") }}
-                    {{- "foo"|transchoice(1) }}
-                    {{- "foo"|transchoice(1, {}, "custom") }}
+                    {{- "foo"|trans(count=1) }}
+                    {{- "foo"|trans({"%count%":1}, "custom") }}
                 {% endblock %}
             ',
 
@@ -174,12 +247,12 @@ class TranslationExtensionTest extends TestCase
 
                 {%- block content %}
                     {{- "foo"|trans(arguments = {}, domain = "custom") }}
-                    {{- "foo"|transchoice(count = 1) }}
-                    {{- "foo"|transchoice(count = 1, arguments = {}, domain = "custom") }}
+                    {{- "foo"|trans(count = 1) }}
+                    {{- "foo"|trans(count = 1, arguments = {}, domain = "custom") }}
                     {{- "foo"|trans({}, domain = "custom") }}
                     {{- "foo"|trans({}, "custom", locale = "fr") }}
-                    {{- "foo"|transchoice(1, arguments = {}, domain = "custom") }}
-                    {{- "foo"|transchoice(1, {}, "custom", locale = "fr") }}
+                    {{- "foo"|trans(arguments = {"%count%":1}, domain = "custom") }}
+                    {{- "foo"|trans({"%count%":1}, "custom", locale = "fr") }}
                 {% endblock %}
             ',
 
diff --git a/src/Symfony/Bridge/Twig/Tests/Node/TransNodeTest.php b/src/Symfony/Bridge/Twig/Tests/Node/TransNodeTest.php
index d45f60c09d..e4a20d72fc 100644
--- a/src/Symfony/Bridge/Twig/Tests/Node/TransNodeTest.php
+++ b/src/Symfony/Bridge/Twig/Tests/Node/TransNodeTest.php
@@ -34,7 +34,7 @@ class TransNodeTest extends TestCase
 
         $this->assertEquals(
             sprintf(
-                'echo $this->env->getExtension(\'Symfony\Bridge\Twig\Extension\TranslationExtension\')->getTranslator()->trans("trans %%var%%", array_merge(array("%%var%%" => %s), %s), "messages");',
+                'echo $this->env->getExtension(\'Symfony\Bridge\Twig\Extension\TranslationExtension\')->trans("trans %%var%%", array_merge(array("%%var%%" => %s), %s), "messages");',
                 $this->getVariableGetterWithoutStrictCheck('var'),
                 $this->getVariableGetterWithStrictCheck('foo')
              ),
diff --git a/src/Symfony/Bridge/Twig/Tests/Translation/TwigExtractorTest.php b/src/Symfony/Bridge/Twig/Tests/Translation/TwigExtractorTest.php
index e46ba205e5..fca5f4d4a9 100644
--- a/src/Symfony/Bridge/Twig/Tests/Translation/TwigExtractorTest.php
+++ b/src/Symfony/Bridge/Twig/Tests/Translation/TwigExtractorTest.php
@@ -50,15 +50,21 @@ class TwigExtractorTest extends TestCase
         }
     }
 
+    /**
+     * @group legacy
+     * @dataProvider getLegacyExtractData
+     */
+    public function testLegacyExtract($template, $messages)
+    {
+        $this->testExtract($template, $messages);
+    }
+
     public function getExtractData()
     {
         return array(
             array('{{ "new key" | trans() }}', array('new key' => 'messages')),
             array('{{ "new key" | trans() | upper }}', array('new key' => 'messages')),
             array('{{ "new key" | trans({}, "domain") }}', array('new key' => 'domain')),
-            array('{{ "new key" | transchoice(1) }}', array('new key' => 'messages')),
-            array('{{ "new key" | transchoice(1) | upper }}', array('new key' => 'messages')),
-            array('{{ "new key" | transchoice(1, {}, "domain") }}', array('new key' => 'domain')),
             array('{% trans %}new key{% endtrans %}', array('new key' => 'messages')),
             array('{% trans %}  new key  {% endtrans %}', array('new key' => 'messages')),
             array('{% trans from "domain" %}new key{% endtrans %}', array('new key' => 'domain')),
@@ -67,11 +73,27 @@ class TwigExtractorTest extends TestCase
 
             // make sure 'trans_default_domain' tag is supported
             array('{% trans_default_domain "domain" %}{{ "new key"|trans }}', array('new key' => 'domain')),
-            array('{% trans_default_domain "domain" %}{{ "new key"|transchoice }}', array('new key' => 'domain')),
             array('{% trans_default_domain "domain" %}{% trans %}new key{% endtrans %}', array('new key' => 'domain')),
 
             // make sure this works with twig's named arguments
             array('{{ "new key" | trans(domain="domain") }}', array('new key' => 'domain')),
+        );
+    }
+
+    /**
+     * @group legacy
+     */
+    public function getLegacyExtractData()
+    {
+        return array(
+            array('{{ "new key" | transchoice(1) }}', array('new key' => 'messages')),
+            array('{{ "new key" | transchoice(1) | upper }}', array('new key' => 'messages')),
+            array('{{ "new key" | transchoice(1, {}, "domain") }}', array('new key' => 'domain')),
+
+            // make sure 'trans_default_domain' tag is supported
+            array('{% trans_default_domain "domain" %}{{ "new key"|transchoice }}', array('new key' => 'domain')),
+
+            // make sure this works with twig's named arguments
             array('{{ "new key" | transchoice(domain="domain", count=1) }}', array('new key' => 'domain')),
         );
     }
diff --git a/src/Symfony/Bridge/Twig/TokenParser/TransChoiceTokenParser.php b/src/Symfony/Bridge/Twig/TokenParser/TransChoiceTokenParser.php
index 5261d7ad52..490fb14ff4 100644
--- a/src/Symfony/Bridge/Twig/TokenParser/TransChoiceTokenParser.php
+++ b/src/Symfony/Bridge/Twig/TokenParser/TransChoiceTokenParser.php
@@ -23,6 +23,8 @@ use Twig\Token;
  * Token Parser for the 'transchoice' tag.
  *
  * @author Fabien Potencier <fabien@symfony.com>
+ *
+ * @deprecated since Symfony 4.2, use the "trans" tag with a "%count%" parameter instead
  */
 class TransChoiceTokenParser extends TransTokenParser
 {
@@ -38,6 +40,8 @@ class TransChoiceTokenParser extends TransTokenParser
         $lineno = $token->getLine();
         $stream = $this->parser->getStream();
 
+        @trigger_error(sprintf('The "transchoice" tag is deprecated since Symfony 4.2, use the "trans" one instead with a "%count%" parameter in %s line %d.', $stream->getSourceContext()->getName(), $lineno), E_USER_DEPRECATED);
+
         $vars = new ArrayExpression(array(), $lineno);
 
         $count = $this->parser->getExpressionParser()->parseExpression();
diff --git a/src/Symfony/Bridge/Twig/TokenParser/TransTokenParser.php b/src/Symfony/Bridge/Twig/TokenParser/TransTokenParser.php
index 76c8dc0610..f5bf12b57e 100644
--- a/src/Symfony/Bridge/Twig/TokenParser/TransTokenParser.php
+++ b/src/Symfony/Bridge/Twig/TokenParser/TransTokenParser.php
@@ -39,10 +39,17 @@ class TransTokenParser extends AbstractTokenParser
         $lineno = $token->getLine();
         $stream = $this->parser->getStream();
 
+        $count = null;
         $vars = new ArrayExpression(array(), $lineno);
         $domain = null;
         $locale = null;
         if (!$stream->test(Token::BLOCK_END_TYPE)) {
+            if ($stream->test('count')) {
+                // {% trans count 5 %}
+                $stream->next();
+                $count = $this->parser->getExpressionParser()->parseExpression();
+            }
+
             if ($stream->test('with')) {
                 // {% trans with vars %}
                 $stream->next();
@@ -74,7 +81,7 @@ class TransTokenParser extends AbstractTokenParser
 
         $stream->expect(Token::BLOCK_END_TYPE);
 
-        return new TransNode($body, $domain, null, $vars, $locale, $lineno, $this->getTag());
+        return new TransNode($body, $domain, $count, $vars, $locale, $lineno, $this->getTag());
     }
 
     public function decideTransFork($token)
diff --git a/src/Symfony/Bundle/FrameworkBundle/CHANGELOG.md b/src/Symfony/Bundle/FrameworkBundle/CHANGELOG.md
index e2e5666489..ed75ed1f90 100644
--- a/src/Symfony/Bundle/FrameworkBundle/CHANGELOG.md
+++ b/src/Symfony/Bundle/FrameworkBundle/CHANGELOG.md
@@ -18,6 +18,7 @@ CHANGELOG
    the "APP_ENV" environment variable instead.
  * Deprecated the `--no-debug` console option, set the "APP_DEBUG" 
    environment variable to "0" instead.
+ * Deprecated the `Templating\Helper\TranslatorHelper::transChoice()` method, use the `trans()` one instead with a `%count%` parameter
 
 4.1.0
 -----
diff --git a/src/Symfony/Bundle/FrameworkBundle/Command/TranslationDebugCommand.php b/src/Symfony/Bundle/FrameworkBundle/Command/TranslationDebugCommand.php
index dc14dea0ef..6e2c1324ba 100644
--- a/src/Symfony/Bundle/FrameworkBundle/Command/TranslationDebugCommand.php
+++ b/src/Symfony/Bundle/FrameworkBundle/Command/TranslationDebugCommand.php
@@ -26,6 +26,7 @@ use Symfony\Component\Translation\LoggingTranslator;
 use Symfony\Component\Translation\MessageCatalogue;
 use Symfony\Component\Translation\Reader\TranslationReaderInterface;
 use Symfony\Component\Translation\Translator;
+use Symfony\Component\Translation\TranslatorInterface as LegacyTranslatorInterface;
 use Symfony\Contracts\Translation\TranslatorInterface;
 
 /**
@@ -50,8 +51,14 @@ class TranslationDebugCommand extends Command
     private $defaultTransPath;
     private $defaultViewsPath;
 
-    public function __construct(TranslatorInterface $translator, TranslationReaderInterface $reader, ExtractorInterface $extractor, string $defaultTransPath = null, string $defaultViewsPath = null)
+    /**
+     * @param TranslatorInterface $translator
+     */
+    public function __construct($translator, TranslationReaderInterface $reader, ExtractorInterface $extractor, string $defaultTransPath = null, string $defaultViewsPath = null)
     {
+        if (!$translator instanceof LegacyTranslatorInterface && !$translator instanceof TranslatorInterface) {
+            throw new \TypeError(sprintf('Argument 1 passed to %s() must be an instance of %s, %s given.', __METHOD__, TranslatorInterface::class, \is_object($translator) ? \get_class($translator) : \gettype($translator)));
+        }
         parent::__construct();
 
         $this->translator = $translator;
diff --git a/src/Symfony/Bundle/FrameworkBundle/Templating/Helper/TranslatorHelper.php b/src/Symfony/Bundle/FrameworkBundle/Templating/Helper/TranslatorHelper.php
index 2052fef695..8120a0cd8e 100644
--- a/src/Symfony/Bundle/FrameworkBundle/Templating/Helper/TranslatorHelper.php
+++ b/src/Symfony/Bundle/FrameworkBundle/Templating/Helper/TranslatorHelper.php
@@ -12,7 +12,6 @@
 namespace Symfony\Bundle\FrameworkBundle\Templating\Helper;
 
 use Symfony\Component\Templating\Helper\Helper;
-use Symfony\Component\Translation\LegacyTranslatorTrait;
 use Symfony\Component\Translation\TranslatorInterface as LegacyTranslatorInterface;
 use Symfony\Contracts\Translation\TranslatorInterface;
 use Symfony\Contracts\Translation\TranslatorTrait;
@@ -28,14 +27,16 @@ class TranslatorHelper extends Helper
         trans as private doTrans;
     }
 
-    use LegacyTranslatorTrait {
-        transChoice as private doTransChoice;
-    }
-
     protected $translator;
 
-    public function __construct(TranslatorInterface $translator = null)
+    /**
+     * @param TranslatorInterface|null $translator
+     */
+    public function __construct($translator = null)
     {
+        if (null !== $translator && !$translator instanceof LegacyTranslatorInterface && !$translator instanceof TranslatorInterface) {
+            throw new \TypeError(sprintf('Argument 1 passed to %s() must be an instance of %s, %s given.', __METHOD__, TranslatorInterface::class, \is_object($translator) ? \get_class($translator) : \gettype($translator)));
+        }
         $this->translator = $translator;
     }
 
@@ -53,11 +54,17 @@ class TranslatorHelper extends Helper
 
     /**
      * @see TranslatorInterface::transChoice()
+     * @deprecated since Symfony 4.2, use the trans() method instead with a %count% parameter
      */
     public function transChoice($id, $number, array $parameters = array(), $domain = 'messages', $locale = null)
     {
-        if (null === $this->translator || !$this->translator instanceof LegacyTranslatorInterface) {
-            return $this->doTransChoice($id, $number, $parameters, $domain, $locale);
+        @trigger_error(sprintf('The "%s()" method is deprecated since Symfony 4.2, use the trans() one instead with a "%count%" parameter.', __METHOD__), E_USER_DEPRECATED);
+
+        if (null === $this->translator) {
+            return $this->doTrans($id, array('%count%' => $number) + $parameters, $domain, $locale);
+        }
+        if ($this->translator instanceof TranslatorInterface) {
+            return $this->translator->trans($id, array('%count%' => $number) + $parameters, $domain, $locale);
         }
 
         return $this->translator->transChoice($id, $number, $parameters, $domain, $locale);
diff --git a/src/Symfony/Bundle/FrameworkBundle/Tests/Translation/TranslatorTest.php b/src/Symfony/Bundle/FrameworkBundle/Tests/Translation/TranslatorTest.php
index 93e070040b..f5a4818553 100644
--- a/src/Symfony/Bundle/FrameworkBundle/Tests/Translation/TranslatorTest.php
+++ b/src/Symfony/Bundle/FrameworkBundle/Tests/Translation/TranslatorTest.php
@@ -52,8 +52,10 @@ class TranslatorTest extends TestCase
         $this->assertEquals('foo (FR)', $translator->trans('foo'));
         $this->assertEquals('bar (EN)', $translator->trans('bar'));
         $this->assertEquals('foobar (ES)', $translator->trans('foobar'));
+        $this->assertEquals('choice 0 (EN)', $translator->trans('choice', array('%count%' => 0)));
         $this->assertEquals('no translation', $translator->trans('no translation'));
         $this->assertEquals('foobarfoo (PT-PT)', $translator->trans('foobarfoo'));
+        $this->assertEquals('other choice 1 (PT-BR)', $translator->trans('other choice', array('%count%' => 1)));
         $this->assertEquals('foobarbaz (fr.UTF-8)', $translator->trans('foobarbaz'));
         $this->assertEquals('foobarbax (sr@latin)', $translator->trans('foobarbax'));
     }
@@ -81,8 +83,10 @@ class TranslatorTest extends TestCase
         $this->assertEquals('foo (FR)', $translator->trans('foo'));
         $this->assertEquals('bar (EN)', $translator->trans('bar'));
         $this->assertEquals('foobar (ES)', $translator->trans('foobar'));
+        $this->assertEquals('choice 0 (EN)', $translator->trans('choice', array('%count%' => 0)));
         $this->assertEquals('no translation', $translator->trans('no translation'));
         $this->assertEquals('foobarfoo (PT-PT)', $translator->trans('foobarfoo'));
+        $this->assertEquals('other choice 1 (PT-BR)', $translator->trans('other choice', array('%count%' => 1)));
         $this->assertEquals('foobarbaz (fr.UTF-8)', $translator->trans('foobarbaz'));
         $this->assertEquals('foobarbax (sr@latin)', $translator->trans('foobarbax'));
 
diff --git a/src/Symfony/Component/Form/Extension/Csrf/CsrfExtension.php b/src/Symfony/Component/Form/Extension/Csrf/CsrfExtension.php
index 8c519a81ec..d84d09b386 100644
--- a/src/Symfony/Component/Form/Extension/Csrf/CsrfExtension.php
+++ b/src/Symfony/Component/Form/Extension/Csrf/CsrfExtension.php
@@ -13,6 +13,7 @@ namespace Symfony\Component\Form\Extension\Csrf;
 
 use Symfony\Component\Form\AbstractExtension;
 use Symfony\Component\Security\Csrf\CsrfTokenManagerInterface;
+use Symfony\Component\Translation\TranslatorInterface as LegacyTranslatorInterface;
 use Symfony\Contracts\Translation\TranslatorInterface;
 
 /**
@@ -28,11 +29,14 @@ class CsrfExtension extends AbstractExtension
 
     /**
      * @param CsrfTokenManagerInterface $tokenManager      The CSRF token manager
-     * @param TranslatorInterface       $translator        The translator for translating error messages
+     * @param TranslatorInterface|null  $translator        The translator for translating error messages
      * @param string|null               $translationDomain The translation domain for translating
      */
-    public function __construct(CsrfTokenManagerInterface $tokenManager, TranslatorInterface $translator = null, string $translationDomain = null)
+    public function __construct(CsrfTokenManagerInterface $tokenManager, $translator = null, string $translationDomain = null)
     {
+        if (null !== $translator && !$translator instanceof LegacyTranslatorInterface && !$translator instanceof TranslatorInterface) {
+            throw new \TypeError(sprintf('Argument 2 passed to %s() must be an instance of %s, %s given.', __METHOD__, TranslatorInterface::class, \is_object($translator) ? \get_class($translator) : \gettype($translator)));
+        }
         $this->tokenManager = $tokenManager;
         $this->translator = $translator;
         $this->translationDomain = $translationDomain;
diff --git a/src/Symfony/Component/Form/Extension/Csrf/EventListener/CsrfValidationListener.php b/src/Symfony/Component/Form/Extension/Csrf/EventListener/CsrfValidationListener.php
index f898737843..4a49a85fcd 100644
--- a/src/Symfony/Component/Form/Extension/Csrf/EventListener/CsrfValidationListener.php
+++ b/src/Symfony/Component/Form/Extension/Csrf/EventListener/CsrfValidationListener.php
@@ -18,6 +18,7 @@ use Symfony\Component\Form\FormEvents;
 use Symfony\Component\Form\Util\ServerParams;
 use Symfony\Component\Security\Csrf\CsrfToken;
 use Symfony\Component\Security\Csrf\CsrfTokenManagerInterface;
+use Symfony\Component\Translation\TranslatorInterface as LegacyTranslatorInterface;
 use Symfony\Contracts\Translation\TranslatorInterface;
 
 /**
@@ -40,8 +41,14 @@ class CsrfValidationListener implements EventSubscriberInterface
         );
     }
 
-    public function __construct(string $fieldName, CsrfTokenManagerInterface $tokenManager, string $tokenId, string $errorMessage, TranslatorInterface $translator = null, string $translationDomain = null, ServerParams $serverParams = null)
+    /**
+     * @param TranslatorInterface|null $translator
+     */
+    public function __construct(string $fieldName, CsrfTokenManagerInterface $tokenManager, string $tokenId, string $errorMessage, $translator = null, string $translationDomain = null, ServerParams $serverParams = null)
     {
+        if (null !== $translator && !$translator instanceof LegacyTranslatorInterface && !$translator instanceof TranslatorInterface) {
+            throw new \TypeError(sprintf('Argument 5 passed to %s() must be an instance of %s, %s given.', __METHOD__, TranslatorInterface::class, \is_object($translator) ? \get_class($translator) : \gettype($translator)));
+        }
         $this->fieldName = $fieldName;
         $this->tokenManager = $tokenManager;
         $this->tokenId = $tokenId;
diff --git a/src/Symfony/Component/Form/Extension/Csrf/Type/FormTypeCsrfExtension.php b/src/Symfony/Component/Form/Extension/Csrf/Type/FormTypeCsrfExtension.php
index 35621c585b..7e16f6dc37 100644
--- a/src/Symfony/Component/Form/Extension/Csrf/Type/FormTypeCsrfExtension.php
+++ b/src/Symfony/Component/Form/Extension/Csrf/Type/FormTypeCsrfExtension.php
@@ -19,6 +19,7 @@ use Symfony\Component\Form\FormView;
 use Symfony\Component\Form\Util\ServerParams;
 use Symfony\Component\OptionsResolver\OptionsResolver;
 use Symfony\Component\Security\Csrf\CsrfTokenManagerInterface;
+use Symfony\Component\Translation\TranslatorInterface as LegacyTranslatorInterface;
 use Symfony\Contracts\Translation\TranslatorInterface;
 
 /**
@@ -33,8 +34,14 @@ class FormTypeCsrfExtension extends AbstractTypeExtension
     private $translationDomain;
     private $serverParams;
 
-    public function __construct(CsrfTokenManagerInterface $defaultTokenManager, bool $defaultEnabled = true, string $defaultFieldName = '_token', TranslatorInterface $translator = null, string $translationDomain = null, ServerParams $serverParams = null)
+    /**
+     * @param TranslatorInterface|null $translator
+     */
+    public function __construct(CsrfTokenManagerInterface $defaultTokenManager, bool $defaultEnabled = true, string $defaultFieldName = '_token', $translator = null, string $translationDomain = null, ServerParams $serverParams = null)
     {
+        if (null !== $translator && !$translator instanceof LegacyTranslatorInterface && !$translator instanceof TranslatorInterface) {
+            throw new \TypeError(sprintf('Argument 4 passed to %s() must be an instance of %s, %s given.', __METHOD__, TranslatorInterface::class, \is_object($translator) ? \get_class($translator) : \gettype($translator)));
+        }
         $this->defaultTokenManager = $defaultTokenManager;
         $this->defaultEnabled = $defaultEnabled;
         $this->defaultFieldName = $defaultFieldName;
diff --git a/src/Symfony/Component/Form/Extension/Validator/Type/UploadValidatorExtension.php b/src/Symfony/Component/Form/Extension/Validator/Type/UploadValidatorExtension.php
index fa09cbc21f..9e5eec8001 100644
--- a/src/Symfony/Component/Form/Extension/Validator/Type/UploadValidatorExtension.php
+++ b/src/Symfony/Component/Form/Extension/Validator/Type/UploadValidatorExtension.php
@@ -14,6 +14,7 @@ namespace Symfony\Component\Form\Extension\Validator\Type;
 use Symfony\Component\Form\AbstractTypeExtension;
 use Symfony\Component\OptionsResolver\Options;
 use Symfony\Component\OptionsResolver\OptionsResolver;
+use Symfony\Component\Translation\TranslatorInterface as LegacyTranslatorInterface;
 use Symfony\Contracts\Translation\TranslatorInterface;
 
 /**
@@ -25,8 +26,14 @@ class UploadValidatorExtension extends AbstractTypeExtension
     private $translator;
     private $translationDomain;
 
-    public function __construct(TranslatorInterface $translator, string $translationDomain = null)
+    /**
+     * @param TranslatorInterface $translator
+     */
+    public function __construct($translator, string $translationDomain = null)
     {
+        if (!$translator instanceof LegacyTranslatorInterface && !$translator instanceof TranslatorInterface) {
+            throw new \TypeError(sprintf('Argument 1 passed to %s() must be an instance of %s, %s given.', __METHOD__, TranslatorInterface::class, \is_object($translator) ? \get_class($translator) : \gettype($translator)));
+        }
         $this->translator = $translator;
         $this->translationDomain = $translationDomain;
     }
diff --git a/src/Symfony/Component/HttpKernel/EventListener/TranslatorListener.php b/src/Symfony/Component/HttpKernel/EventListener/TranslatorListener.php
index 792e347816..7cf059886d 100644
--- a/src/Symfony/Component/HttpKernel/EventListener/TranslatorListener.php
+++ b/src/Symfony/Component/HttpKernel/EventListener/TranslatorListener.php
@@ -17,6 +17,7 @@ use Symfony\Component\HttpFoundation\RequestStack;
 use Symfony\Component\HttpKernel\Event\FinishRequestEvent;
 use Symfony\Component\HttpKernel\Event\GetResponseEvent;
 use Symfony\Component\HttpKernel\KernelEvents;
+use Symfony\Component\Translation\TranslatorInterface as LegacyTranslatorInterface;
 use Symfony\Contracts\Translation\TranslatorInterface;
 
 /**
@@ -29,8 +30,14 @@ class TranslatorListener implements EventSubscriberInterface
     private $translator;
     private $requestStack;
 
-    public function __construct(TranslatorInterface $translator, RequestStack $requestStack)
+    /**
+     * @param TranslatorInterface $translator
+     */
+    public function __construct($translator, RequestStack $requestStack)
     {
+        if (!$translator instanceof LegacyTranslatorInterface && !$translator instanceof TranslatorInterface) {
+            throw new \TypeError(sprintf('Argument 1 passed to %s() must be an instance of %s, %s given.', __METHOD__, TranslatorInterface::class, \is_object($translator) ? \get_class($translator) : \gettype($translator)));
+        }
         $this->translator = $translator;
         $this->requestStack = $requestStack;
     }
diff --git a/src/Symfony/Component/Translation/CHANGELOG.md b/src/Symfony/Component/Translation/CHANGELOG.md
index 87b7e5a9f1..e3a4725c3d 100644
--- a/src/Symfony/Component/Translation/CHANGELOG.md
+++ b/src/Symfony/Component/Translation/CHANGELOG.md
@@ -5,7 +5,7 @@ CHANGELOG
 -----
 
  * Started using ICU parent locales as fallback locales.
- * deprecated `Translator::transChoice()` in favor of using `Translator::trans()` with intl message format 
+ * deprecated `Translator::transChoice()` in favor of using `Translator::trans()` with a `%count%` parameter
  * deprecated `TranslatorInterface` in favor of `Symfony\Contracts\Translation\TranslatorInterface`
  * deprecated `MessageSelector`, `Interval` and `PluralizationRules`; use `IdentityTranslator` instead
  * Added `IntlMessageFormatter` and `FallbackMessageFormatter`
diff --git a/src/Symfony/Component/Translation/DataCollectorTranslator.php b/src/Symfony/Component/Translation/DataCollectorTranslator.php
index fd8c135e26..3e2087220d 100644
--- a/src/Symfony/Component/Translation/DataCollectorTranslator.php
+++ b/src/Symfony/Component/Translation/DataCollectorTranslator.php
@@ -18,12 +18,8 @@ use Symfony\Contracts\Translation\TranslatorInterface;
 /**
  * @author Abdellatif Ait boudad <a.aitboudad@gmail.com>
  */
-class DataCollectorTranslator implements LegacyTranslatorInterface, TranslatorBagInterface
+class DataCollectorTranslator implements LegacyTranslatorInterface, TranslatorInterface, TranslatorBagInterface
 {
-    use LegacyTranslatorTrait {
-        transChoice as private doTransChoice;
-    }
-
     const MESSAGE_DEFINED = 0;
     const MESSAGE_MISSING = 1;
     const MESSAGE_EQUALS_FALLBACK = 2;
@@ -38,8 +34,11 @@ class DataCollectorTranslator implements LegacyTranslatorInterface, TranslatorBa
     /**
      * @param TranslatorInterface $translator The translator must implement TranslatorBagInterface
      */
-    public function __construct(TranslatorInterface $translator)
+    public function __construct($translator)
     {
+        if (!$translator instanceof LegacyTranslatorInterface && !$translator instanceof TranslatorInterface) {
+            throw new \TypeError(sprintf('Argument 1 passed to %s() must be an instance of %s, %s given.', __METHOD__, TranslatorInterface::class, \is_object($translator) ? \get_class($translator) : \gettype($translator)));
+        }
         if (!$translator instanceof TranslatorBagInterface) {
             throw new InvalidArgumentException(sprintf('The Translator "%s" must implement TranslatorInterface and TranslatorBagInterface.', \get_class($translator)));
         }
@@ -60,16 +59,18 @@ class DataCollectorTranslator implements LegacyTranslatorInterface, TranslatorBa
 
     /**
      * {@inheritdoc}
+     *
+     * @deprecated since Symfony 4.2, use the trans() method instead with a %count% parameter
      */
     public function transChoice($id, $number, array $parameters = array(), $domain = null, $locale = null)
     {
-        if ($this->translator instanceof LegacyTranslatorInterface) {
-            $trans = $this->translator->transChoice($id, $number, $parameters, $domain, $locale);
-        } else {
-            $trans = $this->doTransChoice($id, $number, $parameters, $domain, $locale);
+        if ($this->translator instanceof TranslatorInterface) {
+            $trans = $this->translator->trans($id, array('%count%' => $number) + $parameters, $domain, $locale);
         }
 
-        $this->collectMessage($locale, $domain, $id, $trans, $parameters, $number);
+        $trans = $this->translator->transChoice($id, $number, $parameters, $domain, $locale);
+
+        $this->collectMessage($locale, $domain, $id, $trans, array('%count%' => $number) + $parameters);
 
         return $trans;
     }
@@ -134,9 +135,8 @@ class DataCollectorTranslator implements LegacyTranslatorInterface, TranslatorBa
      * @param string      $id
      * @param string      $translation
      * @param array|null  $parameters
-     * @param int|null    $number
      */
-    private function collectMessage($locale, $domain, $id, $translation, $parameters = array(), $number = null)
+    private function collectMessage($locale, $domain, $id, $translation, $parameters = array())
     {
         if (null === $domain) {
             $domain = 'messages';
@@ -169,8 +169,8 @@ class DataCollectorTranslator implements LegacyTranslatorInterface, TranslatorBa
             'id' => $id,
             'translation' => $translation,
             'parameters' => $parameters,
-            'transChoiceNumber' => $number,
             'state' => $state,
+            'transChoiceNumber' => isset($parameters['%count%']) && is_numeric($parameters['%count%']) ? $parameters['%count%'] : null,
         );
     }
 }
diff --git a/src/Symfony/Component/Translation/Formatter/ChoiceMessageFormatterInterface.php b/src/Symfony/Component/Translation/Formatter/ChoiceMessageFormatterInterface.php
index 92acbcafe2..6bc68384af 100644
--- a/src/Symfony/Component/Translation/Formatter/ChoiceMessageFormatterInterface.php
+++ b/src/Symfony/Component/Translation/Formatter/ChoiceMessageFormatterInterface.php
@@ -13,6 +13,8 @@ namespace Symfony\Component\Translation\Formatter;
 
 /**
  * @author Abdellatif Ait boudad <a.aitboudad@gmail.com>
+ *
+ * @deprecated since Symfony 4.2, use MessageFormatterInterface::format() with a %count% parameter instead
  */
 interface ChoiceMessageFormatterInterface
 {
diff --git a/src/Symfony/Component/Translation/Formatter/MessageFormatter.php b/src/Symfony/Component/Translation/Formatter/MessageFormatter.php
index 862e03aab1..1119c356f5 100644
--- a/src/Symfony/Component/Translation/Formatter/MessageFormatter.php
+++ b/src/Symfony/Component/Translation/Formatter/MessageFormatter.php
@@ -13,6 +13,7 @@ namespace Symfony\Component\Translation\Formatter;
 
 use Symfony\Component\Translation\IdentityTranslator;
 use Symfony\Component\Translation\MessageSelector;
+use Symfony\Component\Translation\TranslatorInterface as LegacyTranslatorInterface;
 use Symfony\Contracts\Translation\TranslatorInterface;
 
 /**
@@ -29,7 +30,7 @@ class MessageFormatter implements MessageFormatterInterface, ChoiceMessageFormat
     {
         if ($translator instanceof MessageSelector) {
             $translator = new IdentityTranslator($translator);
-        } elseif (null !== $translator && !$translator instanceof TranslatorInterface) {
+        } elseif (null !== $translator && !$translator instanceof TranslatorInterface && !$translator instanceof LegacyTranslatorInterface) {
             throw new \TypeError(sprintf('Argument 1 passed to %s() must be an instance of %s, %s given.', __METHOD__, TranslatorInterface::class, \is_object($translator) ? \get_class($translator) : \gettype($translator)));
         }
 
@@ -41,15 +42,27 @@ class MessageFormatter implements MessageFormatterInterface, ChoiceMessageFormat
      */
     public function format($message, $locale, array $parameters = array())
     {
+        if ($this->translator instanceof TranslatorInterface) {
+            return $this->translator->trans($message, $parameters, null, $locale);
+        }
+
         return strtr($message, $parameters);
     }
 
     /**
      * {@inheritdoc}
+     *
+     * @deprecated since Symfony 4.2, use format() with a %count% parameter instead
      */
     public function choiceFormat($message, $number, $locale, array $parameters = array())
     {
-        $parameters = array_merge(array('%count%' => $number), $parameters);
+        @trigger_error(sprintf('The "%s()" method is deprecated since Symfony 4.2, use the format() one instead with a %count% parameter.', __METHOD__), E_USER_DEPRECATED);
+
+        $parameters = array('%count%' => $number) + $parameters;
+
+        if ($this->translator instanceof TranslatorInterface) {
+            return $this->format($message, $locale, $parameters);
+        }
 
         return $this->format($this->translator->transChoice($message, $number, array(), null, $locale), $locale, $parameters);
     }
diff --git a/src/Symfony/Component/Translation/IdentityTranslator.php b/src/Symfony/Component/Translation/IdentityTranslator.php
index c138563049..31abdaab12 100644
--- a/src/Symfony/Component/Translation/IdentityTranslator.php
+++ b/src/Symfony/Component/Translation/IdentityTranslator.php
@@ -11,6 +11,8 @@
 
 namespace Symfony\Component\Translation;
 
+use Symfony\Component\Translation\TranslatorInterface as LegacyTranslatorInterface;
+use Symfony\Contracts\Translation\TranslatorInterface;
 use Symfony\Contracts\Translation\TranslatorTrait;
 
 /**
@@ -18,12 +20,9 @@ use Symfony\Contracts\Translation\TranslatorTrait;
  *
  * @author Fabien Potencier <fabien@symfony.com>
  */
-class IdentityTranslator implements TranslatorInterface
+class IdentityTranslator implements LegacyTranslatorInterface, TranslatorInterface
 {
     use TranslatorTrait;
-    use LegacyTranslatorTrait {
-        transChoice as private doTransChoice;
-    }
 
     private $selector;
 
@@ -41,14 +40,22 @@ class IdentityTranslator implements TranslatorInterface
 
     /**
      * {@inheritdoc}
+     *
+     * @deprecated since Symfony 4.2, use the trans() method instead with a %count% parameter
      */
     public function transChoice($id, $number, array $parameters = array(), $domain = null, $locale = null)
     {
-        @trigger_error(sprintf('The "%s()" method is deprecated since Symfony 4.2, use the "trans()" method with intl formatted messages instead.', __METHOD__), E_USER_DEPRECATED);
+        @trigger_error(sprintf('The "%s()" method is deprecated since Symfony 4.2, use the trans() one instead with a "%count%" parameter.', __METHOD__), E_USER_DEPRECATED);
+
         if ($this->selector) {
             return strtr($this->selector->choose((string) $id, $number, $locale ?: $this->getLocale()), $parameters);
         }
 
-        return $this->doTransChoice($id, $number, $parameters, $domain, $locale);
+        return $this->trans($id, array('%count%' => $number) + $parameters, $domain, $locale);
+    }
+
+    private function getPluralizationRule(int $number, string $locale): int
+    {
+        return PluralizationRules::get($number, $locale, false);
     }
 }
diff --git a/src/Symfony/Component/Translation/LegacyTranslatorTrait.php b/src/Symfony/Component/Translation/LegacyTranslatorTrait.php
deleted file mode 100644
index 1b24372206..0000000000
--- a/src/Symfony/Component/Translation/LegacyTranslatorTrait.php
+++ /dev/null
@@ -1,110 +0,0 @@
-<?php
-
-/*
- * This file is part of the Symfony package.
- *
- * (c) Fabien Potencier <fabien@symfony.com>
- *
- * For the full copyright and license information, please view the LICENSE
- * file that was distributed with this source code.
- */
-
-namespace Symfony\Component\Translation;
-
-use Symfony\Component\Translation\Exception\InvalidArgumentException;
-
-/**
- * @author Tobias Nyholm <tobias.nyholm@gmail.com>
- * @author Fabien Potencier <fabien@symfony.com>
- *
- * @deprecated since Symfony 4.2, use IdentityTranslator instead
- */
-trait LegacyTranslatorTrait
-{
-    /**
-     * Implementation of Symfony\Component\Translation\TranslationInterface::transChoice
-     * {@inheritdoc}
-     */
-    public function transChoice($id, $number, array $parameters = array(), $domain = null, $locale = null)
-    {
-        @trigger_error(sprintf('The "%s()" method is deprecated since Symfony 4.2, use the "trans()" method with intl formatted messages instead.', __METHOD__), E_USER_DEPRECATED);
-
-        $id = (string) $id;
-        $number = (float) $number;
-        $locale = (string) $locale ?: $this->getLocale();
-
-        $parts = array();
-        if (preg_match('/^\|++$/', $id)) {
-            $parts = explode('|', $id);
-        } elseif (preg_match_all('/(?:\|\||[^\|])++/', $id, $matches)) {
-            $parts = $matches[0];
-        }
-
-        $intervalRegexp = <<<'EOF'
-/^(?P<interval>
-    ({\s*
-        (\-?\d+(\.\d+)?[\s*,\s*\-?\d+(\.\d+)?]*)
-    \s*})
-
-        |
-
-    (?P<left_delimiter>[\[\]])
-        \s*
-        (?P<left>-Inf|\-?\d+(\.\d+)?)
-        \s*,\s*
-        (?P<right>\+?Inf|\-?\d+(\.\d+)?)
-        \s*
-    (?P<right_delimiter>[\[\]])
-)\s*(?P<message>.*?)$/xs
-EOF;
-
-        $standardRules = array();
-        foreach ($parts as $part) {
-            $part = trim(str_replace('||', '|', $part));
-
-            // try to match an explicit rule, then fallback to the standard ones
-            if (preg_match($intervalRegexp, $part, $matches)) {
-                if ($matches[2]) {
-                    foreach (explode(',', $matches[3]) as $n) {
-                        if ($number == $n) {
-                            return strtr($matches['message'], $parameters);
-                        }
-                    }
-                } else {
-                    $leftNumber = '-Inf' === $matches['left'] ? -INF : (float) $matches['left'];
-                    $rightNumber = \is_numeric($matches['right']) ? (float) $matches['right'] : INF;
-
-                    if (('[' === $matches['left_delimiter'] ? $number >= $leftNumber : $number > $leftNumber)
-                        && (']' === $matches['right_delimiter'] ? $number <= $rightNumber : $number < $rightNumber)
-                    ) {
-                        return strtr($matches['message'], $parameters);
-                    }
-                }
-            } elseif (preg_match('/^\w+\:\s*(.*?)$/', $part, $matches)) {
-                $standardRules[] = $matches[1];
-            } else {
-                $standardRules[] = $part;
-            }
-        }
-
-        $position = PluralizationRules::get($number, $locale, false);
-
-        if (!isset($standardRules[$position])) {
-            // when there's exactly one rule given, and that rule is a standard
-            // rule, use this rule
-            if (1 === \count($parts) && isset($standardRules[0])) {
-                return strtr($standardRules[0], $parameters);
-            }
-
-            $message = sprintf('Unable to choose a translation for "%s" with locale "%s" for value "%d". Double check that this translation has the correct plural options (e.g. "There is one apple|There are %%count%% apples").', $id, $locale, $number);
-
-            if (\class_exists(InvalidArgumentException::class)) {
-                throw new InvalidArgumentException($message);
-            }
-
-            throw new \InvalidArgumentException($message);
-        }
-
-        return strtr($standardRules[$position], $parameters);
-    }
-}
diff --git a/src/Symfony/Component/Translation/LoggingTranslator.php b/src/Symfony/Component/Translation/LoggingTranslator.php
index 7a10952a2a..ee711568ab 100644
--- a/src/Symfony/Component/Translation/LoggingTranslator.php
+++ b/src/Symfony/Component/Translation/LoggingTranslator.php
@@ -21,10 +21,6 @@ use Symfony\Contracts\Translation\TranslatorInterface;
  */
 class LoggingTranslator implements LegacyTranslatorInterface, TranslatorBagInterface
 {
-    use LegacyTranslatorTrait {
-        transChoice as private doTransChoice;
-    }
-
     /**
      * @var TranslatorInterface|TranslatorBagInterface
      */
@@ -36,8 +32,11 @@ class LoggingTranslator implements LegacyTranslatorInterface, TranslatorBagInter
      * @param TranslatorInterface $translator The translator must implement TranslatorBagInterface
      * @param LoggerInterface     $logger
      */
-    public function __construct(TranslatorInterface $translator, LoggerInterface $logger)
+    public function __construct($translator, LoggerInterface $logger)
     {
+        if (!$translator instanceof LegacyTranslatorInterface && !$translator instanceof TranslatorInterface) {
+            throw new \TypeError(sprintf('Argument 1 passed to %s() must be an instance of %s, %s given.', __METHOD__, TranslatorInterface::class, \is_object($translator) ? \get_class($translator) : \gettype($translator)));
+        }
         if (!$translator instanceof TranslatorBagInterface) {
             throw new InvalidArgumentException(sprintf('The Translator "%s" must implement TranslatorInterface and TranslatorBagInterface.', \get_class($translator)));
         }
@@ -59,13 +58,17 @@ class LoggingTranslator implements LegacyTranslatorInterface, TranslatorBagInter
 
     /**
      * {@inheritdoc}
+     *
+     * @deprecated since Symfony 4.2, use the trans() method instead with a %count% parameter
      */
     public function transChoice($id, $number, array $parameters = array(), $domain = null, $locale = null)
     {
-        if ($this->translator instanceof LegacyTranslatorInterface) {
-            $trans = $this->translator->transChoice($id, $number, $parameters, $domain, $locale);
+        @trigger_error(sprintf('The "%s()" method is deprecated since Symfony 4.2, use the trans() one instead with a "%count%" parameter.', __METHOD__), E_USER_DEPRECATED);
+
+        if ($this->translator instanceof TranslatorInterface) {
+            $trans = $this->translator->trans($id, array('%count%' => $number) + $parameters, $domain, $locale);
         } else {
-            $trans = $this->doTransChoice($id, $number, $parameters, $domain, $locale);
+            $trans = $this->translator->transChoice($id, $number, $parameters, $domain, $locale);
         }
 
         $this->log($id, $domain, $locale);
diff --git a/src/Symfony/Component/Translation/Tests/DataCollectorTranslatorTest.php b/src/Symfony/Component/Translation/Tests/DataCollectorTranslatorTest.php
index ae15339bce..19e056c12e 100644
--- a/src/Symfony/Component/Translation/Tests/DataCollectorTranslatorTest.php
+++ b/src/Symfony/Component/Translation/Tests/DataCollectorTranslatorTest.php
@@ -25,6 +25,7 @@ class DataCollectorTranslatorTest extends TestCase
 
         $collector->trans('foo');
         $collector->trans('bar');
+        $collector->trans('choice', array('%count%' => 0));
         $collector->trans('bar_ru');
         $collector->trans('bar_ru', array('foo' => 'bar'));
 
@@ -47,6 +48,15 @@ class DataCollectorTranslatorTest extends TestCase
             'parameters' => array(),
             'transChoiceNumber' => null,
         );
+        $expectedMessages[] = array(
+            'id' => 'choice',
+            'translation' => 'choice',
+            'locale' => 'en',
+            'domain' => 'messages',
+            'state' => DataCollectorTranslator::MESSAGE_MISSING,
+            'parameters' => array('%count%' => 0),
+            'transChoiceNumber' => 0,
+        );
         $expectedMessages[] = array(
             'id' => 'bar_ru',
             'translation' => 'bar (ru)',
@@ -86,7 +96,7 @@ class DataCollectorTranslatorTest extends TestCase
               'locale' => 'en',
               'domain' => 'messages',
               'state' => DataCollectorTranslator::MESSAGE_MISSING,
-              'parameters' => array(),
+              'parameters' => array('%count%' => 0),
               'transChoiceNumber' => 0,
         );
 
diff --git a/src/Symfony/Component/Translation/Tests/IdentityTranslatorTest.php b/src/Symfony/Component/Translation/Tests/IdentityTranslatorTest.php
index 443c63718e..be0a548aa1 100644
--- a/src/Symfony/Component/Translation/Tests/IdentityTranslatorTest.php
+++ b/src/Symfony/Component/Translation/Tests/IdentityTranslatorTest.php
@@ -20,193 +20,4 @@ class IdentityTranslatorTest extends TranslatorTest
     {
         return new IdentityTranslator();
     }
-
-    /**
-     * @dataProvider getTransChoiceTests
-     * @group legacy
-     */
-    public function testTransChoiceWithExplicitLocale($expected, $id, $number, $parameters)
-    {
-        $translator = $this->getTranslator();
-        $translator->setLocale('en');
-
-        $this->assertEquals($expected, $translator->transChoice($id, $number, $parameters));
-    }
-
-    /**
-     * @dataProvider getTransChoiceTests
-     * @group legacy
-     */
-    public function testTransChoiceWithDefaultLocale($expected, $id, $number, $parameters)
-    {
-        \Locale::setDefault('en');
-
-        $translator = $this->getTranslator();
-
-        $this->assertEquals($expected, $translator->transChoice($id, $number, $parameters));
-    }
-
-    /**
-     * @dataProvider getInternal
-     * @group legacy
-     */
-    public function testInterval($expected, $number, $interval)
-    {
-        $translator = $this->getTranslator();
-
-        $this->assertEquals($expected, $translator->transChoice($interval.' foo|[1,Inf[ bar', $number));
-    }
-
-    /**
-     * @dataProvider getChooseTests
-     * @group legacy
-     */
-    public function testChoose($expected, $id, $number)
-    {
-        $translator = $this->getTranslator();
-
-        $this->assertEquals($expected, $translator->transChoice($id, $number));
-    }
-
-    /**
-     * @group legacy
-     */
-    public function testReturnMessageIfExactlyOneStandardRuleIsGiven()
-    {
-        $translator = $this->getTranslator();
-
-        $this->assertEquals('There are two apples', $translator->transChoice('There are two apples', 2));
-    }
-
-    /**
-     * @dataProvider getNonMatchingMessages
-     * @expectedException \InvalidArgumentException
-     * @group legacy
-     */
-    public function testThrowExceptionIfMatchingMessageCannotBeFound($id, $number)
-    {
-        $translator = $this->getTranslator();
-
-        $translator->transChoice($id, $number);
-    }
-
-    public function getTransChoiceTests()
-    {
-        return array(
-            array('There are no apples', '{0} There are no apples|{1} There is one apple|]1,Inf] There are %count% apples', 0, array('%count%' => 0)),
-            array('There is one apple', '{0} There are no apples|{1} There is one apple|]1,Inf] There are %count% apples', 1, array('%count%' => 1)),
-            array('There are 10 apples', '{0} There are no apples|{1} There is one apple|]1,Inf] There are %count% apples', 10, array('%count%' => 10)),
-            array('There are 0 apples', 'There is 1 apple|There are %count% apples', 0, array('%count%' => 0)),
-            array('There is 1 apple', 'There is 1 apple|There are %count% apples', 1, array('%count%' => 1)),
-            array('There are 10 apples', 'There is 1 apple|There are %count% apples', 10, array('%count%' => 10)),
-            // custom validation messages may be coded with a fixed value
-            array('There are 2 apples', 'There are 2 apples', 2, array('%count%' => 2)),
-        );
-    }
-
-    public function getInternal()
-    {
-        return array(
-            array('foo', 3, '{1,2, 3 ,4}'),
-            array('bar', 10, '{1,2, 3 ,4}'),
-            array('bar', 3, '[1,2]'),
-            array('foo', 1, '[1,2]'),
-            array('foo', 2, '[1,2]'),
-            array('bar', 1, ']1,2['),
-            array('bar', 2, ']1,2['),
-            array('foo', log(0), '[-Inf,2['),
-            array('foo', -log(0), '[-2,+Inf]'),
-        );
-    }
-
-    public function getNonMatchingMessages()
-    {
-        return array(
-            array('{0} There are no apples|{1} There is one apple', 2),
-            array('{1} There is one apple|]1,Inf] There are %count% apples', 0),
-            array('{1} There is one apple|]2,Inf] There are %count% apples', 2),
-            array('{0} There are no apples|There is one apple', 2),
-        );
-    }
-
-    public function getChooseTests()
-    {
-        return array(
-            array('There are no apples', '{0} There are no apples|{1} There is one apple|]1,Inf] There are %count% apples', 0),
-            array('There are no apples', '{0}     There are no apples|{1} There is one apple|]1,Inf] There are %count% apples', 0),
-            array('There are no apples', '{0}There are no apples|{1} There is one apple|]1,Inf] There are %count% apples', 0),
-
-            array('There is one apple', '{0} There are no apples|{1} There is one apple|]1,Inf] There are %count% apples', 1),
-
-            array('There are %count% apples', '{0} There are no apples|{1} There is one apple|]1,Inf] There are %count% apples', 10),
-            array('There are %count% apples', '{0} There are no apples|{1} There is one apple|]1,Inf]There are %count% apples', 10),
-            array('There are %count% apples', '{0} There are no apples|{1} There is one apple|]1,Inf]     There are %count% apples', 10),
-
-            array('There are %count% apples', 'There is one apple|There are %count% apples', 0),
-            array('There is one apple', 'There is one apple|There are %count% apples', 1),
-            array('There are %count% apples', 'There is one apple|There are %count% apples', 10),
-
-            array('There are %count% apples', 'one: There is one apple|more: There are %count% apples', 0),
-            array('There is one apple', 'one: There is one apple|more: There are %count% apples', 1),
-            array('There are %count% apples', 'one: There is one apple|more: There are %count% apples', 10),
-
-            array('There are no apples', '{0} There are no apples|one: There is one apple|more: There are %count% apples', 0),
-            array('There is one apple', '{0} There are no apples|one: There is one apple|more: There are %count% apples', 1),
-            array('There are %count% apples', '{0} There are no apples|one: There is one apple|more: There are %count% apples', 10),
-
-            array('', '{0}|{1} There is one apple|]1,Inf] There are %count% apples', 0),
-            array('', '{0} There are no apples|{1}|]1,Inf] There are %count% apples', 1),
-
-            // Indexed only tests which are Gettext PoFile* compatible strings.
-            array('There are %count% apples', 'There is one apple|There are %count% apples', 0),
-            array('There is one apple', 'There is one apple|There are %count% apples', 1),
-            array('There are %count% apples', 'There is one apple|There are %count% apples', 2),
-
-            // Tests for float numbers
-            array('There is almost one apple', '{0} There are no apples|]0,1[ There is almost one apple|{1} There is one apple|[1,Inf] There is more than one apple', 0.7),
-            array('There is one apple', '{0} There are no apples|]0,1[There are %count% apples|{1} There is one apple|[1,Inf] There is more than one apple', 1),
-            array('There is more than one apple', '{0} There are no apples|]0,1[There are %count% apples|{1} There is one apple|[1,Inf] There is more than one apple', 1.7),
-            array('There are no apples', '{0} There are no apples|]0,1[There are %count% apples|{1} There is one apple|[1,Inf] There is more than one apple', 0),
-            array('There are no apples', '{0} There are no apples|]0,1[There are %count% apples|{1} There is one apple|[1,Inf] There is more than one apple', 0.0),
-            array('There are no apples', '{0.0} There are no apples|]0,1[There are %count% apples|{1} There is one apple|[1,Inf] There is more than one apple', 0),
-
-            // Test texts with new-lines
-            // with double-quotes and \n in id & double-quotes and actual newlines in text
-            array("This is a text with a\n            new-line in it. Selector = 0.", '{0}This is a text with a
-            new-line in it. Selector = 0.|{1}This is a text with a
-            new-line in it. Selector = 1.|[1,Inf]This is a text with a
-            new-line in it. Selector > 1.', 0),
-            // with double-quotes and \n in id and single-quotes and actual newlines in text
-            array("This is a text with a\n            new-line in it. Selector = 1.", '{0}This is a text with a
-            new-line in it. Selector = 0.|{1}This is a text with a
-            new-line in it. Selector = 1.|[1,Inf]This is a text with a
-            new-line in it. Selector > 1.', 1),
-            array("This is a text with a\n            new-line in it. Selector > 1.", '{0}This is a text with a
-            new-line in it. Selector = 0.|{1}This is a text with a
-            new-line in it. Selector = 1.|[1,Inf]This is a text with a
-            new-line in it. Selector > 1.', 5),
-            // with double-quotes and id split accros lines
-            array('This is a text with a
-            new-line in it. Selector = 1.', '{0}This is a text with a
-            new-line in it. Selector = 0.|{1}This is a text with a
-            new-line in it. Selector = 1.|[1,Inf]This is a text with a
-            new-line in it. Selector > 1.', 1),
-            // with single-quotes and id split accros lines
-            array('This is a text with a
-            new-line in it. Selector > 1.', '{0}This is a text with a
-            new-line in it. Selector = 0.|{1}This is a text with a
-            new-line in it. Selector = 1.|[1,Inf]This is a text with a
-            new-line in it. Selector > 1.', 5),
-            // with single-quotes and \n in text
-            array('This is a text with a\nnew-line in it. Selector = 0.', '{0}This is a text with a\nnew-line in it. Selector = 0.|{1}This is a text with a\nnew-line in it. Selector = 1.|[1,Inf]This is a text with a\nnew-line in it. Selector > 1.', 0),
-            // with double-quotes and id split accros lines
-            array("This is a text with a\nnew-line in it. Selector = 1.", "{0}This is a text with a\nnew-line in it. Selector = 0.|{1}This is a text with a\nnew-line in it. Selector = 1.|[1,Inf]This is a text with a\nnew-line in it. Selector > 1.", 1),
-            // esacape pipe
-            array('This is a text with | in it. Selector = 0.', '{0}This is a text with || in it. Selector = 0.|{1}This is a text with || in it. Selector = 1.', 0),
-            // Empty plural set (2 plural forms) from a .PO file
-            array('', '|', 1),
-            // Empty plural set (3 plural forms) from a .PO file
-            array('', '||', 1),
-        );
-    }
 }
diff --git a/src/Symfony/Component/Translation/Tests/TranslatorTest.php b/src/Symfony/Component/Translation/Tests/TranslatorTest.php
index c632d69041..d630a7491d 100644
--- a/src/Symfony/Component/Translation/Tests/TranslatorTest.php
+++ b/src/Symfony/Component/Translation/Tests/TranslatorTest.php
@@ -502,7 +502,7 @@ class TranslatorTest extends TestCase
             array('Il y a 0 pomme', new StringClass('{0} There are no appless|{1} There is one apple|]1,Inf] There is %count% apples'), '[0,1] Il y a %count% pomme|]1,Inf] Il y a %count% pommes', 0, array(), 'fr', ''),
 
             // Override %count% with a custom value
-            array('Il y a quelques pommes', 'one: There is one apple|more: There are %count% apples', 'one: Il y a %count% pomme|more: Il y a %count% pommes', 2, array('%count%' => 'quelques'), 'fr', ''),
+            array('Il y a quelques pommes', 'one: There is one apple|more: There are %count% apples', 'one: Il y a %count% pomme|more: Il y a quelques pommes', 2, array('%count%' => 'quelques'), 'fr', ''),
         );
     }
 
diff --git a/src/Symfony/Component/Translation/Translator.php b/src/Symfony/Component/Translation/Translator.php
index 5670e613e3..d8d27301f0 100644
--- a/src/Symfony/Component/Translation/Translator.php
+++ b/src/Symfony/Component/Translation/Translator.php
@@ -22,11 +22,13 @@ use Symfony\Component\Translation\Formatter\ChoiceMessageFormatterInterface;
 use Symfony\Component\Translation\Formatter\MessageFormatter;
 use Symfony\Component\Translation\Formatter\MessageFormatterInterface;
 use Symfony\Component\Translation\Loader\LoaderInterface;
+use Symfony\Component\Translation\TranslatorInterface as LegacyTranslatorInterface;
+use Symfony\Contracts\Translation\TranslatorInterface;
 
 /**
  * @author Fabien Potencier <fabien@symfony.com>
  */
-class Translator implements TranslatorInterface, TranslatorBagInterface
+class Translator implements LegacyTranslatorInterface, TranslatorInterface, TranslatorBagInterface
 {
     /**
      * @var MessageCatalogueInterface[]
@@ -199,10 +201,13 @@ class Translator implements TranslatorInterface, TranslatorBagInterface
 
     /**
      * {@inheritdoc}
+     *
+     * @deprecated since Symfony 4.2, use the trans() method instead with a %count% parameter
      */
     public function transChoice($id, $number, array $parameters = array(), $domain = null, $locale = null)
     {
-        @trigger_error(sprintf('The "%s()" method is deprecated since Symfony 4.2, use the "trans()" method with intl formatted messages instead.', __METHOD__), E_USER_DEPRECATED);
+        @trigger_error(sprintf('The "%s()" method is deprecated since Symfony 4.2, use the trans() one instead with a "%count%" parameter.', __METHOD__), E_USER_DEPRECATED);
+
         if (!$this->formatter instanceof ChoiceMessageFormatterInterface) {
             throw new LogicException(sprintf('The formatter "%s" does not support plural translations.', \get_class($this->formatter)));
         }
diff --git a/src/Symfony/Component/Translation/TranslatorInterface.php b/src/Symfony/Component/Translation/TranslatorInterface.php
index 2eea19866b..02cb5027b8 100644
--- a/src/Symfony/Component/Translation/TranslatorInterface.php
+++ b/src/Symfony/Component/Translation/TranslatorInterface.php
@@ -11,48 +11,34 @@
 
 namespace Symfony\Component\Translation;
 
-use Symfony\Contracts\Translation\TranslatorInterface as BaseTranslatorInterface;
+use Symfony\Component\Translation\Exception\InvalidArgumentException;
 
 /**
+ * TranslatorInterface.
+ *
  * @author Fabien Potencier <fabien@symfony.com>
  *
- * @deprecated since Symfony 4.2, use the interface from the Symfony\Contracts\Translation namespace
+ * @deprecated since Symfony 4.2, use Symfony\Contracts\Translation\TranslatorInterface instead
  */
-interface TranslatorInterface extends BaseTranslatorInterface
+interface TranslatorInterface
 {
+    /**
+     * Translates the given message.
+     *
+     * @param string      $id         The message id (may also be an object that can be cast to string)
+     * @param array       $parameters An array of parameters for the message
+     * @param string|null $domain     The domain for the message or null to use the default
+     * @param string|null $locale     The locale or null to use the default
+     *
+     * @return string The translated string
+     *
+     * @throws InvalidArgumentException If the locale contains invalid characters
+     */
+    public function trans($id, array $parameters = array(), $domain = null, $locale = null);
+
     /**
      * Translates the given choice message by choosing a translation according to a number.
      *
-     * Given a message with different plural translations separated by a
-     * pipe (|), this method returns the correct portion of the message based
-     * on the given number, locale and the pluralization rules in the message
-     * itself.
-     *
-     * The message supports two different types of pluralization rules:
-     *
-     * interval: {0} There are no apples|{1} There is one apple|]1,Inf] There are %count% apples
-     * indexed:  There is one apple|There are %count% apples
-     *
-     * The indexed solution can also contain labels (e.g. one: There is one apple).
-     * This is purely for making the translations more clear - it does not
-     * affect the functionality.
-     *
-     * The two methods can also be mixed:
-     *     {0} There are no apples|one: There is one apple|more: There are %count% apples
-     *
-     * An interval can represent a finite set of numbers:
-     *  {1,2,3,4}
-     *
-     * An interval can represent numbers between two numbers:
-     *  [1, +Inf]
-     *  ]-1,2[
-     *
-     * The left delimiter can be [ (inclusive) or ] (exclusive).
-     * The right delimiter can be [ (exclusive) or ] (inclusive).
-     * Beside numbers, you can use -Inf and +Inf for the infinite.
-     *
-     * @see https://en.wikipedia.org/wiki/ISO_31-11
-     *
      * @param string      $id         The message id (may also be an object that can be cast to string)
      * @param int         $number     The number to use to find the indice of the message
      * @param array       $parameters An array of parameters for the message
@@ -61,9 +47,23 @@ interface TranslatorInterface extends BaseTranslatorInterface
      *
      * @return string The translated string
      *
-     * @throws \InvalidArgumentException If the locale contains invalid characters
-     *
-     * @deprecated since Symfony 4.2
+     * @throws InvalidArgumentException If the locale contains invalid characters
      */
     public function transChoice($id, $number, array $parameters = array(), $domain = null, $locale = null);
+
+    /**
+     * Sets the current locale.
+     *
+     * @param string $locale The locale
+     *
+     * @throws InvalidArgumentException If the locale contains invalid characters
+     */
+    public function setLocale($locale);
+
+    /**
+     * Returns the current locale.
+     *
+     * @return string The locale
+     */
+    public function getLocale();
 }
diff --git a/src/Symfony/Component/Validator/Context/ExecutionContext.php b/src/Symfony/Component/Validator/Context/ExecutionContext.php
index 03f56e9175..fd9d9605e0 100644
--- a/src/Symfony/Component/Validator/Context/ExecutionContext.php
+++ b/src/Symfony/Component/Validator/Context/ExecutionContext.php
@@ -11,6 +11,7 @@
 
 namespace Symfony\Component\Validator\Context;
 
+use Symfony\Component\Translation\TranslatorInterface as LegacyTranslatorInterface;
 use Symfony\Component\Validator\Constraint;
 use Symfony\Component\Validator\ConstraintViolation;
 use Symfony\Component\Validator\ConstraintViolationList;
@@ -140,8 +141,11 @@ class ExecutionContext implements ExecutionContextInterface
      * @internal Called by {@link ExecutionContextFactory}. Should not be used
      *           in user code.
      */
-    public function __construct(ValidatorInterface $validator, $root, TranslatorInterface $translator, string $translationDomain = null)
+    public function __construct(ValidatorInterface $validator, $root, $translator, string $translationDomain = null)
     {
+        if (!$translator instanceof LegacyTranslatorInterface && !$translator instanceof TranslatorInterface) {
+            throw new \TypeError(sprintf('Argument 3 passed to %s() must be an instance of %s, %s given.', __METHOD__, TranslatorInterface::class, \is_object($translator) ? \get_class($translator) : \gettype($translator)));
+        }
         $this->validator = $validator;
         $this->root = $root;
         $this->translator = $translator;
diff --git a/src/Symfony/Component/Validator/Context/ExecutionContextFactory.php b/src/Symfony/Component/Validator/Context/ExecutionContextFactory.php
index 0bb1be767e..b8d56eee9a 100644
--- a/src/Symfony/Component/Validator/Context/ExecutionContextFactory.php
+++ b/src/Symfony/Component/Validator/Context/ExecutionContextFactory.php
@@ -11,6 +11,7 @@
 
 namespace Symfony\Component\Validator\Context;
 
+use Symfony\Component\Translation\TranslatorInterface as LegacyTranslatorInterface;
 use Symfony\Component\Validator\Validator\ValidatorInterface;
 use Symfony\Contracts\Translation\TranslatorInterface;
 
@@ -34,8 +35,12 @@ class ExecutionContextFactory implements ExecutionContextFactoryInterface
      *                                               use for translating
      *                                               violation messages
      */
-    public function __construct(TranslatorInterface $translator, string $translationDomain = null)
+    public function __construct($translator, string $translationDomain = null)
     {
+        if (!$translator instanceof LegacyTranslatorInterface && !$translator instanceof TranslatorInterface) {
+            throw new \TypeError(sprintf('Argument 1 passed to %s() must be an instance of %s, %s given.', __METHOD__, TranslatorInterface::class, \is_object($translator) ? \get_class($translator) : \gettype($translator)));
+        }
+
         $this->translator = $translator;
         $this->translationDomain = $translationDomain;
     }
diff --git a/src/Symfony/Component/Validator/Util/LegacyTranslatorProxy.php b/src/Symfony/Component/Validator/Util/LegacyTranslatorProxy.php
index 972c9bd931..12f487bf2f 100644
--- a/src/Symfony/Component/Validator/Util/LegacyTranslatorProxy.php
+++ b/src/Symfony/Component/Validator/Util/LegacyTranslatorProxy.php
@@ -11,18 +11,14 @@
 
 namespace Symfony\Component\Validator\Util;
 
-use Symfony\Component\Translation\LegacyTranslatorTrait;
 use Symfony\Component\Translation\TranslatorInterface as LegacyTranslatorInterface;
 use Symfony\Contracts\Translation\TranslatorInterface;
 
 /**
  * @internal to be removed in Symfony 5.0.
  */
-class LegacyTranslatorProxy implements LegacyTranslatorInterface
+class LegacyTranslatorProxy implements LegacyTranslatorInterface, TranslatorInterface
 {
-    use LegacyTranslatorTrait {
-        transChoice as private doTransChoice;
-    }
     private $translator;
 
     public function __construct(TranslatorInterface $translator)
@@ -64,10 +60,6 @@ class LegacyTranslatorProxy implements LegacyTranslatorInterface
      */
     public function transChoice($id, $number, array $parameters = array(), $domain = null, $locale = null)
     {
-        if ($this->translator instanceof LegacyTranslatorInterface) {
-            return $this->translator->transChoice($id, $number, $parameters, $domain, $locale);
-        }
-
-        $this->doTransChoice($id, $number, $parameters, $domain, $locale);
+        return $this->translator->trans($id, array('%count%' => $number) + $parameters, $domain, $locale);
     }
 }
diff --git a/src/Symfony/Component/Validator/Violation/ConstraintViolationBuilder.php b/src/Symfony/Component/Validator/Violation/ConstraintViolationBuilder.php
index 34b49f962a..abca36a536 100644
--- a/src/Symfony/Component/Validator/Violation/ConstraintViolationBuilder.php
+++ b/src/Symfony/Component/Validator/Violation/ConstraintViolationBuilder.php
@@ -44,8 +44,14 @@ class ConstraintViolationBuilder implements ConstraintViolationBuilderInterface
      */
     private $cause;
 
-    public function __construct(ConstraintViolationList $violations, Constraint $constraint, $message, array $parameters, $root, $propertyPath, $invalidValue, TranslatorInterface $translator, $translationDomain = null)
+    /**
+     * @param TranslatorInterface $translator
+     */
+    public function __construct(ConstraintViolationList $violations, Constraint $constraint, $message, array $parameters, $root, $propertyPath, $invalidValue, $translator, $translationDomain = null)
     {
+        if (!$translator instanceof LegacyTranslatorInterface && !$translator instanceof TranslatorInterface) {
+            throw new \TypeError(sprintf('Argument 8 passed to %s() must be an instance of %s, %s given.', __METHOD__, TranslatorInterface::class, \is_object($translator) ? \get_class($translator) : \gettype($translator)));
+        }
         $this->violations = $violations;
         $this->message = $message;
         $this->parameters = $parameters;
@@ -142,12 +148,18 @@ class ConstraintViolationBuilder implements ConstraintViolationBuilderInterface
      */
     public function addViolation()
     {
-        if (null === $this->plural || !$this->translator instanceof LegacyTranslatorInterface) {
+        if (null === $this->plural) {
             $translatedMessage = $this->translator->trans(
                 $this->message,
                 $this->parameters,
                 $this->translationDomain
             );
+        } elseif ($this->translator instanceof TranslatorInterface) {
+            $translatedMessage = $this->translator->trans(
+                $this->message,
+                array('%count%' => $this->plural) + $this->parameters,
+                $this->translationDomain
+            );
         } else {
             try {
                 $translatedMessage = $this->translator->transChoice(
diff --git a/src/Symfony/Contracts/Tests/Translation/TranslatorTest.php b/src/Symfony/Contracts/Tests/Translation/TranslatorTest.php
index a7642bfa11..a3b67dfe5e 100644
--- a/src/Symfony/Contracts/Tests/Translation/TranslatorTest.php
+++ b/src/Symfony/Contracts/Tests/Translation/TranslatorTest.php
@@ -47,6 +47,29 @@ class TranslatorTest extends TestCase
         $this->assertEquals($expected, $translator->trans($id, $parameters));
     }
 
+    /**
+     * @dataProvider getTransChoiceTests
+     */
+    public function testTransChoiceWithExplicitLocale($expected, $id, $number)
+    {
+        $translator = $this->getTranslator();
+        $translator->setLocale('en');
+
+        $this->assertEquals($expected, $translator->trans($id, array('%count%' => $number)));
+    }
+
+    /**
+     * @dataProvider getTransChoiceTests
+     */
+    public function testTransChoiceWithDefaultLocale($expected, $id, $number)
+    {
+        \Locale::setDefault('en');
+
+        $translator = $this->getTranslator();
+
+        $this->assertEquals($expected, $translator->trans($id, array('%count%' => $number)));
+    }
+
     public function testGetSetLocale()
     {
         $translator = $this->getTranslator();
@@ -76,4 +99,255 @@ class TranslatorTest extends TestCase
             array('Symfony is awesome!', 'Symfony is %what%!', array('%what%' => 'awesome')),
         );
     }
+
+    public function getTransChoiceTests()
+    {
+        return array(
+            array('There are no apples', '{0} There are no apples|{1} There is one apple|]1,Inf] There are %count% apples', 0),
+            array('There is one apple', '{0} There are no apples|{1} There is one apple|]1,Inf] There are %count% apples', 1),
+            array('There are 10 apples', '{0} There are no apples|{1} There is one apple|]1,Inf] There are %count% apples', 10),
+            array('There are 0 apples', 'There is 1 apple|There are %count% apples', 0),
+            array('There is 1 apple', 'There is 1 apple|There are %count% apples', 1),
+            array('There are 10 apples', 'There is 1 apple|There are %count% apples', 10),
+            // custom validation messages may be coded with a fixed value
+            array('There are 2 apples', 'There are 2 apples', 2),
+        );
+    }
+
+    /**
+     * @dataProvider getInternal
+     */
+    public function testInterval($expected, $number, $interval)
+    {
+        $translator = $this->getTranslator();
+
+        $this->assertEquals($expected, $translator->trans($interval.' foo|[1,Inf[ bar', array('%count%' => $number)));
+    }
+
+    public function getInternal()
+    {
+        return array(
+            array('foo', 3, '{1,2, 3 ,4}'),
+            array('bar', 10, '{1,2, 3 ,4}'),
+            array('bar', 3, '[1,2]'),
+            array('foo', 1, '[1,2]'),
+            array('foo', 2, '[1,2]'),
+            array('bar', 1, ']1,2['),
+            array('bar', 2, ']1,2['),
+            array('foo', log(0), '[-Inf,2['),
+            array('foo', -log(0), '[-2,+Inf]'),
+        );
+    }
+
+    /**
+     * @dataProvider getChooseTests
+     */
+    public function testChoose($expected, $id, $number)
+    {
+        $translator = $this->getTranslator();
+
+        $this->assertEquals($expected, $translator->trans($id, array('%count%' => $number)));
+    }
+
+    public function testReturnMessageIfExactlyOneStandardRuleIsGiven()
+    {
+        $translator = $this->getTranslator();
+
+        $this->assertEquals('There are two apples', $translator->trans('There are two apples', array('%count%' => 2)));
+    }
+
+    /**
+     * @dataProvider getNonMatchingMessages
+     * @expectedException \InvalidArgumentException
+     */
+    public function testThrowExceptionIfMatchingMessageCannotBeFound($id, $number)
+    {
+        $translator = $this->getTranslator();
+
+        $translator->trans($id, array('%count%' => $number));
+    }
+
+    public function getNonMatchingMessages()
+    {
+        return array(
+            array('{0} There are no apples|{1} There is one apple', 2),
+            array('{1} There is one apple|]1,Inf] There are %count% apples', 0),
+            array('{1} There is one apple|]2,Inf] There are %count% apples', 2),
+            array('{0} There are no apples|There is one apple', 2),
+        );
+    }
+
+    public function getChooseTests()
+    {
+        return array(
+            array('There are no apples', '{0} There are no apples|{1} There is one apple|]1,Inf] There are %count% apples', 0),
+            array('There are no apples', '{0}     There are no apples|{1} There is one apple|]1,Inf] There are %count% apples', 0),
+            array('There are no apples', '{0}There are no apples|{1} There is one apple|]1,Inf] There are %count% apples', 0),
+
+            array('There is one apple', '{0} There are no apples|{1} There is one apple|]1,Inf] There are %count% apples', 1),
+
+            array('There are 10 apples', '{0} There are no apples|{1} There is one apple|]1,Inf] There are %count% apples', 10),
+            array('There are 10 apples', '{0} There are no apples|{1} There is one apple|]1,Inf]There are %count% apples', 10),
+            array('There are 10 apples', '{0} There are no apples|{1} There is one apple|]1,Inf]     There are %count% apples', 10),
+
+            array('There are 0 apples', 'There is one apple|There are %count% apples', 0),
+            array('There is one apple', 'There is one apple|There are %count% apples', 1),
+            array('There are 10 apples', 'There is one apple|There are %count% apples', 10),
+
+            array('There are 0 apples', 'one: There is one apple|more: There are %count% apples', 0),
+            array('There is one apple', 'one: There is one apple|more: There are %count% apples', 1),
+            array('There are 10 apples', 'one: There is one apple|more: There are %count% apples', 10),
+
+            array('There are no apples', '{0} There are no apples|one: There is one apple|more: There are %count% apples', 0),
+            array('There is one apple', '{0} There are no apples|one: There is one apple|more: There are %count% apples', 1),
+            array('There are 10 apples', '{0} There are no apples|one: There is one apple|more: There are %count% apples', 10),
+
+            array('', '{0}|{1} There is one apple|]1,Inf] There are %count% apples', 0),
+            array('', '{0} There are no apples|{1}|]1,Inf] There are %count% apples', 1),
+
+            // Indexed only tests which are Gettext PoFile* compatible strings.
+            array('There are 0 apples', 'There is one apple|There are %count% apples', 0),
+            array('There is one apple', 'There is one apple|There are %count% apples', 1),
+            array('There are 2 apples', 'There is one apple|There are %count% apples', 2),
+
+            // Tests for float numbers
+            array('There is almost one apple', '{0} There are no apples|]0,1[ There is almost one apple|{1} There is one apple|[1,Inf] There is more than one apple', 0.7),
+            array('There is one apple', '{0} There are no apples|]0,1[There are %count% apples|{1} There is one apple|[1,Inf] There is more than one apple', 1),
+            array('There is more than one apple', '{0} There are no apples|]0,1[There are %count% apples|{1} There is one apple|[1,Inf] There is more than one apple', 1.7),
+            array('There are no apples', '{0} There are no apples|]0,1[There are %count% apples|{1} There is one apple|[1,Inf] There is more than one apple', 0),
+            array('There are no apples', '{0} There are no apples|]0,1[There are %count% apples|{1} There is one apple|[1,Inf] There is more than one apple', 0.0),
+            array('There are no apples', '{0.0} There are no apples|]0,1[There are %count% apples|{1} There is one apple|[1,Inf] There is more than one apple', 0),
+
+            // Test texts with new-lines
+            // with double-quotes and \n in id & double-quotes and actual newlines in text
+            array("This is a text with a\n            new-line in it. Selector = 0.", '{0}This is a text with a
+            new-line in it. Selector = 0.|{1}This is a text with a
+            new-line in it. Selector = 1.|[1,Inf]This is a text with a
+            new-line in it. Selector > 1.', 0),
+            // with double-quotes and \n in id and single-quotes and actual newlines in text
+            array("This is a text with a\n            new-line in it. Selector = 1.", '{0}This is a text with a
+            new-line in it. Selector = 0.|{1}This is a text with a
+            new-line in it. Selector = 1.|[1,Inf]This is a text with a
+            new-line in it. Selector > 1.', 1),
+            array("This is a text with a\n            new-line in it. Selector > 1.", '{0}This is a text with a
+            new-line in it. Selector = 0.|{1}This is a text with a
+            new-line in it. Selector = 1.|[1,Inf]This is a text with a
+            new-line in it. Selector > 1.', 5),
+            // with double-quotes and id split accros lines
+            array('This is a text with a
+            new-line in it. Selector = 1.', '{0}This is a text with a
+            new-line in it. Selector = 0.|{1}This is a text with a
+            new-line in it. Selector = 1.|[1,Inf]This is a text with a
+            new-line in it. Selector > 1.', 1),
+            // with single-quotes and id split accros lines
+            array('This is a text with a
+            new-line in it. Selector > 1.', '{0}This is a text with a
+            new-line in it. Selector = 0.|{1}This is a text with a
+            new-line in it. Selector = 1.|[1,Inf]This is a text with a
+            new-line in it. Selector > 1.', 5),
+            // with single-quotes and \n in text
+            array('This is a text with a\nnew-line in it. Selector = 0.', '{0}This is a text with a\nnew-line in it. Selector = 0.|{1}This is a text with a\nnew-line in it. Selector = 1.|[1,Inf]This is a text with a\nnew-line in it. Selector > 1.', 0),
+            // with double-quotes and id split accros lines
+            array("This is a text with a\nnew-line in it. Selector = 1.", "{0}This is a text with a\nnew-line in it. Selector = 0.|{1}This is a text with a\nnew-line in it. Selector = 1.|[1,Inf]This is a text with a\nnew-line in it. Selector > 1.", 1),
+            // esacape pipe
+            array('This is a text with | in it. Selector = 0.', '{0}This is a text with || in it. Selector = 0.|{1}This is a text with || in it. Selector = 1.', 0),
+            // Empty plural set (2 plural forms) from a .PO file
+            array('', '|', 1),
+            // Empty plural set (3 plural forms) from a .PO file
+            array('', '||', 1),
+        );
+    }
+
+    /**
+     * @dataProvider failingLangcodes
+     */
+    public function testFailedLangcodes($nplural, $langCodes)
+    {
+        $matrix = $this->generateTestData($langCodes);
+        $this->validateMatrix($nplural, $matrix, false);
+    }
+
+    /**
+     * @dataProvider successLangcodes
+     */
+    public function testLangcodes($nplural, $langCodes)
+    {
+        $matrix = $this->generateTestData($langCodes);
+        $this->validateMatrix($nplural, $matrix);
+    }
+
+    /**
+     * This array should contain all currently known langcodes.
+     *
+     * As it is impossible to have this ever complete we should try as hard as possible to have it almost complete.
+     *
+     * @return array
+     */
+    public function successLangcodes()
+    {
+        return array(
+            array('1', array('ay', 'bo', 'cgg', 'dz', 'id', 'ja', 'jbo', 'ka', 'kk', 'km', 'ko', 'ky')),
+            array('2', array('nl', 'fr', 'en', 'de', 'de_GE', 'hy', 'hy_AM')),
+            array('3', array('be', 'bs', 'cs', 'hr')),
+            array('4', array('cy', 'mt', 'sl')),
+            array('6', array('ar')),
+        );
+    }
+
+    /**
+     * This array should be at least empty within the near future.
+     *
+     * This both depends on a complete list trying to add above as understanding
+     * the plural rules of the current failing languages.
+     *
+     * @return array with nplural together with langcodes
+     */
+    public function failingLangcodes()
+    {
+        return array(
+            array('1', array('fa')),
+            array('2', array('jbo')),
+            array('3', array('cbs')),
+            array('4', array('gd', 'kw')),
+            array('5', array('ga')),
+        );
+    }
+
+    /**
+     * We validate only on the plural coverage. Thus the real rules is not tested.
+     *
+     * @param string $nplural       Plural expected
+     * @param array  $matrix        Containing langcodes and their plural index values
+     * @param bool   $expectSuccess
+     */
+    protected function validateMatrix($nplural, $matrix, $expectSuccess = true)
+    {
+        foreach ($matrix as $langCode => $data) {
+            $indexes = array_flip($data);
+            if ($expectSuccess) {
+                $this->assertEquals($nplural, \count($indexes), "Langcode '$langCode' has '$nplural' plural forms.");
+            } else {
+                $this->assertNotEquals((int) $nplural, \count($indexes), "Langcode '$langCode' has '$nplural' plural forms.");
+            }
+        }
+    }
+
+    protected function generateTestData($langCodes)
+    {
+        $translator = new class() {
+            use TranslatorTrait {
+                getPluralizationRule as public;
+            }
+        };
+
+        $matrix = array();
+        foreach ($langCodes as $langCode) {
+            for ($count = 0; $count < 200; ++$count) {
+                $plural = $translator->getPluralizationRule($count, $langCode);
+                $matrix[$langCode][$count] = $plural;
+            }
+        }
+
+        return $matrix;
+    }
 }
diff --git a/src/Symfony/Contracts/Translation/TranslatorInterface.php b/src/Symfony/Contracts/Translation/TranslatorInterface.php
index 7620fd3787..2130c1b2cf 100644
--- a/src/Symfony/Contracts/Translation/TranslatorInterface.php
+++ b/src/Symfony/Contracts/Translation/TranslatorInterface.php
@@ -19,6 +19,39 @@ interface TranslatorInterface
     /**
      * Translates the given message.
      *
+     * When a number is provided as a parameter named "%count%", the message is parsed for plural
+     * forms and a translation is chosen according to this number using the following rules:
+     *
+     * Given a message with different plural translations separated by a
+     * pipe (|), this method returns the correct portion of the message based
+     * on the given number, locale and the pluralization rules in the message
+     * itself.
+     *
+     * The message supports two different types of pluralization rules:
+     *
+     * interval: {0} There are no apples|{1} There is one apple|]1,Inf] There are %count% apples
+     * indexed:  There is one apple|There are %count% apples
+     *
+     * The indexed solution can also contain labels (e.g. one: There is one apple).
+     * This is purely for making the translations more clear - it does not
+     * affect the functionality.
+     *
+     * The two methods can also be mixed:
+     *     {0} There are no apples|one: There is one apple|more: There are %count% apples
+     *
+     * An interval can represent a finite set of numbers:
+     *  {1,2,3,4}
+     *
+     * An interval can represent numbers between two numbers:
+     *  [1, +Inf]
+     *  ]-1,2[
+     *
+     * The left delimiter can be [ (inclusive) or ] (exclusive).
+     * The right delimiter can be [ (exclusive) or ] (inclusive).
+     * Beside numbers, you can use -Inf and +Inf for the infinite.
+     *
+     * @see https://en.wikipedia.org/wiki/ISO_31-11
+     *
      * @param string      $id         The message id (may also be an object that can be cast to string)
      * @param array       $parameters An array of parameters for the message
      * @param string|null $domain     The domain for the message or null to use the default
diff --git a/src/Symfony/Contracts/Translation/TranslatorTrait.php b/src/Symfony/Contracts/Translation/TranslatorTrait.php
index b92105f190..e19e37cfe5 100644
--- a/src/Symfony/Contracts/Translation/TranslatorTrait.php
+++ b/src/Symfony/Contracts/Translation/TranslatorTrait.php
@@ -11,6 +11,8 @@
 
 namespace Symfony\Contracts\Translation;
 
+use Symfony\Component\Translation\Exception\InvalidArgumentException;
+
 /**
  * A trait to help implement TranslatorInterface.
  *
@@ -41,6 +43,213 @@ trait TranslatorTrait
      */
     public function trans($id, array $parameters = array(), $domain = null, $locale = null)
     {
-        return strtr((string) $id, $parameters);
+        $id = (string) $id;
+
+        if (!isset($parameters['%count%']) || !is_numeric($parameters['%count%'])) {
+            return strtr($id, $parameters);
+        }
+
+        $number = (float) $parameters['%count%'];
+        $locale = (string) $locale ?: $this->getLocale();
+
+        $parts = array();
+        if (preg_match('/^\|++$/', $id)) {
+            $parts = explode('|', $id);
+        } elseif (preg_match_all('/(?:\|\||[^\|])++/', $id, $matches)) {
+            $parts = $matches[0];
+        }
+
+        $intervalRegexp = <<<'EOF'
+/^(?P<interval>
+    ({\s*
+        (\-?\d+(\.\d+)?[\s*,\s*\-?\d+(\.\d+)?]*)
+    \s*})
+
+        |
+
+    (?P<left_delimiter>[\[\]])
+        \s*
+        (?P<left>-Inf|\-?\d+(\.\d+)?)
+        \s*,\s*
+        (?P<right>\+?Inf|\-?\d+(\.\d+)?)
+        \s*
+    (?P<right_delimiter>[\[\]])
+)\s*(?P<message>.*?)$/xs
+EOF;
+
+        $standardRules = array();
+        foreach ($parts as $part) {
+            $part = trim(str_replace('||', '|', $part));
+
+            // try to match an explicit rule, then fallback to the standard ones
+            if (preg_match($intervalRegexp, $part, $matches)) {
+                if ($matches[2]) {
+                    foreach (explode(',', $matches[3]) as $n) {
+                        if ($number == $n) {
+                            return strtr($matches['message'], $parameters);
+                        }
+                    }
+                } else {
+                    $leftNumber = '-Inf' === $matches['left'] ? -INF : (float) $matches['left'];
+                    $rightNumber = \is_numeric($matches['right']) ? (float) $matches['right'] : INF;
+
+                    if (('[' === $matches['left_delimiter'] ? $number >= $leftNumber : $number > $leftNumber)
+                        && (']' === $matches['right_delimiter'] ? $number <= $rightNumber : $number < $rightNumber)
+                    ) {
+                        return strtr($matches['message'], $parameters);
+                    }
+                }
+            } elseif (preg_match('/^\w+\:\s*(.*?)$/', $part, $matches)) {
+                $standardRules[] = $matches[1];
+            } else {
+                $standardRules[] = $part;
+            }
+        }
+
+        $position = $this->getPluralizationRule($number, $locale);
+
+        if (!isset($standardRules[$position])) {
+            // when there's exactly one rule given, and that rule is a standard
+            // rule, use this rule
+            if (1 === \count($parts) && isset($standardRules[0])) {
+                return strtr($standardRules[0], $parameters);
+            }
+
+            $message = sprintf('Unable to choose a translation for "%s" with locale "%s" for value "%d". Double check that this translation has the correct plural options (e.g. "There is one apple|There are %%count%% apples").', $id, $locale, $number);
+
+            if (\class_exists(InvalidArgumentException::class)) {
+                throw new InvalidArgumentException($message);
+            }
+
+            throw new \InvalidArgumentException($message);
+        }
+
+        return strtr($standardRules[$position], $parameters);
+    }
+
+    /**
+     * Returns the plural position to use for the given locale and number.
+     *
+     * The plural rules are derived from code of the Zend Framework (2010-09-25),
+     * which is subject to the new BSD license (http://framework.zend.com/license/new-bsd).
+     * Copyright (c) 2005-2010 Zend Technologies USA Inc. (http://www.zend.com)
+     */
+    private function getPluralizationRule(int $number, string $locale): int
+    {
+        switch ('pt_BR' !== $locale && \strlen($locale) > 3 ? substr($locale, 0, strrpos($locale, '_')) : $locale) {
+            case 'af':
+            case 'bn':
+            case 'bg':
+            case 'ca':
+            case 'da':
+            case 'de':
+            case 'el':
+            case 'en':
+            case 'eo':
+            case 'es':
+            case 'et':
+            case 'eu':
+            case 'fa':
+            case 'fi':
+            case 'fo':
+            case 'fur':
+            case 'fy':
+            case 'gl':
+            case 'gu':
+            case 'ha':
+            case 'he':
+            case 'hu':
+            case 'is':
+            case 'it':
+            case 'ku':
+            case 'lb':
+            case 'ml':
+            case 'mn':
+            case 'mr':
+            case 'nah':
+            case 'nb':
+            case 'ne':
+            case 'nl':
+            case 'nn':
+            case 'no':
+            case 'oc':
+            case 'om':
+            case 'or':
+            case 'pa':
+            case 'pap':
+            case 'ps':
+            case 'pt':
+            case 'so':
+            case 'sq':
+            case 'sv':
+            case 'sw':
+            case 'ta':
+            case 'te':
+            case 'tk':
+            case 'ur':
+            case 'zu':
+                return (1 == $number) ? 0 : 1;
+
+            case 'am':
+            case 'bh':
+            case 'fil':
+            case 'fr':
+            case 'gun':
+            case 'hi':
+            case 'hy':
+            case 'ln':
+            case 'mg':
+            case 'nso':
+            case 'pt_BR':
+            case 'ti':
+            case 'wa':
+                return ((0 == $number) || (1 == $number)) ? 0 : 1;
+
+            case 'be':
+            case 'bs':
+            case 'hr':
+            case 'ru':
+            case 'sh':
+            case 'sr':
+            case 'uk':
+                return ((1 == $number % 10) && (11 != $number % 100)) ? 0 : ((($number % 10 >= 2) && ($number % 10 <= 4) && (($number % 100 < 10) || ($number % 100 >= 20))) ? 1 : 2);
+
+            case 'cs':
+            case 'sk':
+                return (1 == $number) ? 0 : ((($number >= 2) && ($number <= 4)) ? 1 : 2);
+
+            case 'ga':
+                return (1 == $number) ? 0 : ((2 == $number) ? 1 : 2);
+
+            case 'lt':
+                return ((1 == $number % 10) && (11 != $number % 100)) ? 0 : ((($number % 10 >= 2) && (($number % 100 < 10) || ($number % 100 >= 20))) ? 1 : 2);
+
+            case 'sl':
+                return (1 == $number % 100) ? 0 : ((2 == $number % 100) ? 1 : (((3 == $number % 100) || (4 == $number % 100)) ? 2 : 3));
+
+            case 'mk':
+                return (1 == $number % 10) ? 0 : 1;
+
+            case 'mt':
+                return (1 == $number) ? 0 : (((0 == $number) || (($number % 100 > 1) && ($number % 100 < 11))) ? 1 : ((($number % 100 > 10) && ($number % 100 < 20)) ? 2 : 3));
+
+            case 'lv':
+                return (0 == $number) ? 0 : (((1 == $number % 10) && (11 != $number % 100)) ? 1 : 2);
+
+            case 'pl':
+                return (1 == $number) ? 0 : ((($number % 10 >= 2) && ($number % 10 <= 4) && (($number % 100 < 12) || ($number % 100 > 14))) ? 1 : 2);
+
+            case 'cy':
+                return (1 == $number) ? 0 : ((2 == $number) ? 1 : (((8 == $number) || (11 == $number)) ? 2 : 3));
+
+            case 'ro':
+                return (1 == $number) ? 0 : (((0 == $number) || (($number % 100 > 0) && ($number % 100 < 20))) ? 1 : 2);
+
+            case 'ar':
+                return (0 == $number) ? 0 : ((1 == $number) ? 1 : ((2 == $number) ? 2 : ((($number % 100 >= 3) && ($number % 100 <= 10)) ? 3 : ((($number % 100 >= 11) && ($number % 100 <= 99)) ? 4 : 5))));
+
+            default:
+                return 0;
+        }
     }
 }