From 16f97b9769144931f00d7f523c4a35db85299ca3 Mon Sep 17 00:00:00 2001
From: Christian Flothmann <christian.flothmann@sensiolabs.de>
Date: Tue, 15 Jan 2019 14:09:02 +0100
Subject: [PATCH 1/2] remove unreachable code

Since our version constraint is `^1.37.1|^2.6.2` any Twig version that
is below 2.4.5 must be a Twig 1.x release.
---
 src/Symfony/Bridge/Twig/Tests/Node/TransNodeTest.php | 6 +-----
 1 file changed, 1 insertion(+), 5 deletions(-)

diff --git a/src/Symfony/Bridge/Twig/Tests/Node/TransNodeTest.php b/src/Symfony/Bridge/Twig/Tests/Node/TransNodeTest.php
index 6e61a7d66a..9fe0861376 100644
--- a/src/Symfony/Bridge/Twig/Tests/Node/TransNodeTest.php
+++ b/src/Symfony/Bridge/Twig/Tests/Node/TransNodeTest.php
@@ -53,12 +53,8 @@ class TransNodeTest extends TestCase
 
     protected function getVariableGetterWithStrictCheck($name)
     {
-        if (Environment::VERSION_ID > 20404) {
-            return sprintf('(isset($context["%s"]) || array_key_exists("%1$s", $context) ? $context["%1$s"] : (function () { throw new Twig_Error_Runtime(\'Variable "%1$s" does not exist.\', 0, $this->source); })())', $name);
-        }
-
         if (Environment::MAJOR_VERSION >= 2) {
-            return sprintf('(isset($context["%s"]) || array_key_exists("%1$s", $context) ? $context["%1$s"] : (function () { throw new Twig_Error_Runtime(\'Variable "%1$s" does not exist.\', 0, $this->getSourceContext()); })())', $name);
+            return sprintf('(isset($context["%s"]) || array_key_exists("%1$s", $context) ? $context["%1$s"] : (function () { throw new Twig_Error_Runtime(\'Variable "%1$s" does not exist.\', 0, $this->source); })())', $name);
         }
 
         if (\PHP_VERSION_ID >= 70000) {

From caca373383ba15aae7084a73bb22c68d3f164cd8 Mon Sep 17 00:00:00 2001
From: Christian Flothmann <christian.flothmann@sensiolabs.de>
Date: Tue, 15 Jan 2019 14:43:24 +0100
Subject: [PATCH 2/2] the string "0" is a valid service identifier

---
 .../Component/DependencyInjection/Loader/XmlFileLoader.php    | 4 ++--
 .../DependencyInjection/Tests/Fixtures/xml/services6.xml      | 4 ++++
 2 files changed, 6 insertions(+), 2 deletions(-)

diff --git a/src/Symfony/Component/DependencyInjection/Loader/XmlFileLoader.php b/src/Symfony/Component/DependencyInjection/Loader/XmlFileLoader.php
index 4236b72f25..4677a61ca4 100644
--- a/src/Symfony/Component/DependencyInjection/Loader/XmlFileLoader.php
+++ b/src/Symfony/Component/DependencyInjection/Loader/XmlFileLoader.php
@@ -496,7 +496,7 @@ class XmlFileLoader extends FileLoader
 
             switch ($arg->getAttribute('type')) {
                 case 'service':
-                    if (!$arg->getAttribute('id')) {
+                    if ('' === $arg->getAttribute('id')) {
                         throw new InvalidArgumentException(sprintf('Tag "<%s>" with type="service" has no or empty "id" attribute in "%s".', $name, $file));
                     }
                     if ($arg->hasAttribute('strict')) {
@@ -549,7 +549,7 @@ class XmlFileLoader extends FileLoader
      * @param \DOMNode $node
      * @param mixed    $name
      *
-     * @return array
+     * @return \DOMElement[]
      */
     private function getChildren(\DOMNode $node, $name)
     {
diff --git a/src/Symfony/Component/DependencyInjection/Tests/Fixtures/xml/services6.xml b/src/Symfony/Component/DependencyInjection/Tests/Fixtures/xml/services6.xml
index cffd5df605..c85b7a7c01 100644
--- a/src/Symfony/Component/DependencyInjection/Tests/Fixtures/xml/services6.xml
+++ b/src/Symfony/Component/DependencyInjection/Tests/Fixtures/xml/services6.xml
@@ -61,5 +61,9 @@
     </service>
     <service id="alias_for_foo" alias="foo" />
     <service id="another_alias_for_foo" alias="foo" public="false" />
+    <service id="0" class="FooClass" />
+    <service id="1" class="FooClass">
+      <argument type="service" id="0" />
+    </service>
   </services>
 </container>