Drupal 8.0.0 beta 12. More info: https://www.drupal.org/node/2514176

core/lib/Drupal/Component/ProxyBuilder/ProxyDumper.php

@@ -0,0 +1,78 @@
+<?php
+
+/**
+ * @file
+ * Contains \Drupal\Component\ProxyBuilder\ProxyDumper.
+ */
+
+namespace Drupal\Component\ProxyBuilder;
+
+use Symfony\Component\DependencyInjection\Definition;
+use Symfony\Component\DependencyInjection\LazyProxy\PhpDumper\DumperInterface;
+
+/**
+ * Dumps the proxy service into the dumped PHP container file.
+ */
+class ProxyDumper implements DumperInterface {
+
+  /**
+   * Keeps track of already existing proxy classes.
+   *
+   * @var array
+   */
+  protected $buildClasses = [];
+
+  /**
+   * The proxy builder.
+   *
+   * @var \Drupal\Component\ProxyBuilder\ProxyBuilder
+   */
+  protected $builder;
+
+  public function __construct(ProxyBuilder $builder) {
+    $this->builder = $builder;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function isProxyCandidate(Definition $definition) {
+    return $definition->isLazy() && ($class = $definition->getClass()) && class_exists($class);
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function getProxyFactoryCode(Definition $definition, $id) {
+    // Note: the specific get method is called initially with $lazyLoad=TRUE;
+    // When you want to retrieve the actual service, the code generated in
+    // ProxyBuilder calls the method with lazy loading disabled.
+    $output = <<<'EOS'
+        if ($lazyLoad) {
+            return $this->services['{{ id }}'] = new {{ class_name }}($this, '{{ id }}');
+        }
+
+EOS;
+    $output = str_replace('{{ id }}', $id, $output);
+    $output = str_replace('{{ class_name }}', $this->builder->buildProxyClassName($definition->getClass()), $output);
+
+    return $output;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function getProxyCode(Definition $definition) {
+    // Maybe the same class is used in different services, which are both marked
+    // as lazy (just think about 2 database connections).
+    // In those cases we should not generate proxy code the second time.
+    if (!isset($this->buildClasses[$definition->getClass()])) {
+      $this->buildClasses[$definition->getClass()] = TRUE;
+      return $this->builder->build($definition->getClass());
+    }
+    else {
+      return '';
+    }
+  }
+
+}