[DI] Ignore missing tree root nodes on validate

Author: ro0NL

Compiler/ValidateEnvPlaceholdersPass.php

@@ -12,6 +12,7 @@
 namespace Symfony\Component\DependencyInjection\Compiler;
 
 use Symfony\Component\Config\Definition\BaseNode;
+use Symfony\Component\Config\Definition\Exception\TreeWithoutRootNodeException;
 use Symfony\Component\Config\Definition\Processor;
 use Symfony\Component\DependencyInjection\ContainerBuilder;
 use Symfony\Component\DependencyInjection\Exception\LogicException;
@@ -77,7 +78,10 @@ public function process(ContainerBuilder $container)
                     continue;
                 }
 
-                $processor->processConfiguration($configuration, $config);
+                try {
+                    $processor->processConfiguration($configuration, $config);
+                } catch (TreeWithoutRootNodeException $e) {
+                }
             }
         } finally {
             BaseNode::resetPlaceholders();

Tests/Compiler/ValidateEnvPlaceholdersPassTest.php

@@ -14,6 +14,7 @@
 use PHPUnit\Framework\TestCase;
 use Symfony\Component\Config\Definition\Builder\TreeBuilder;
 use Symfony\Component\Config\Definition\ConfigurationInterface;
+use Symfony\Component\Config\Definition\Exception\TreeWithoutRootNodeException;
 use Symfony\Component\DependencyInjection\Compiler\MergeExtensionConfigurationPass;
 use Symfony\Component\DependencyInjection\Compiler\RegisterEnvVarProcessorsPass;
 use Symfony\Component\DependencyInjection\Compiler\ValidateEnvPlaceholdersPass;
@@ -222,6 +223,17 @@ public function testEnvWithVariableNode(): void
         $this->assertSame($expected, $container->resolveEnvPlaceholders($ext->getConfig()));
     }
 
+    public function testConfigurationWithoutRootNode(): void
+    {
+        $container = new ContainerBuilder();
+        $container->registerExtension($ext = new EnvExtension(new EnvConfigurationWithoutRootNode()));
+        $container->loadFromExtension('env_extension');
+
+        $this->doProcess($container);
+
+        $this->addToAssertionCount(1);
+    }
+
     private function doProcess(ContainerBuilder $container): void
     {
         (new MergeExtensionConfigurationPass())->process($container);
@@ -267,23 +279,41 @@ public function getConfigTreeBuilder()
     }
 }
 
+class EnvConfigurationWithoutRootNode implements ConfigurationInterface
+{
+    public function getConfigTreeBuilder()
+    {
+        return new TreeBuilder();
+    }
+}
+
 class EnvExtension extends Extension
 {
+    private $configuration;
     private $config;
 
+    public function __construct(ConfigurationInterface $configuration = null)
+    {
+        $this->configuration = $configuration ?? new EnvConfiguration();
+    }
+
     public function getAlias()
     {
         return 'env_extension';
     }
 
     public function getConfiguration(array $config, ContainerBuilder $container)
     {
-        return new EnvConfiguration();
+        return $this->configuration;
     }
 
     public function load(array $configs, ContainerBuilder $container)
     {
-        $this->config = $this->processConfiguration($this->getConfiguration($configs, $container), $configs);
+        try {
+            $this->config = $this->processConfiguration($this->getConfiguration($configs, $container), $configs);
+        } catch (TreeWithoutRootNodeException $e) {
+            $this->config = null;
+        }
     }
 
     public function getConfig()

composer.json

@@ -32,7 +32,7 @@
         "symfony/proxy-manager-bridge": "Generate service proxies to lazy load them"
     },
     "conflict": {
-        "symfony/config": "<4.1",
+        "symfony/config": "<4.1.1",
         "symfony/finder": "<3.4",
         "symfony/proxy-manager-bridge": "<3.4",
         "symfony/yaml": "<3.4"