Update to drupal 8.0.0-rc1. For more information, see https://www.drupal.org/node/2582663

core/lib/Drupal/Component/Plugin/Context/Context.php

@@ -31,20 +31,16 @@ class Context implements ContextInterface {
   protected $contextDefinition;
 
   /**
-   * Sets the contextDefinition for us without needing to call the setter.
+   * Create a context object.
    *
    * @param \Drupal\Component\Plugin\Context\ContextDefinitionInterface $context_definition
    *   The context definition.
+   * @param mixed|null $context_value
+   *   The value of the context.
    */
-  public function __construct(ContextDefinitionInterface $context_definition) {
+  public function __construct(ContextDefinitionInterface $context_definition, $context_value = NULL) {
     $this->contextDefinition = $context_definition;
-  }
-
-  /**
-   * Implements \Drupal\Component\Plugin\Context\ContextInterface::setContextValue().
-   */
-  public function setContextValue($value) {
-    $this->contextValue = $value;
+    $this->contextValue = $context_value;
   }
 
   /**
@@ -74,13 +70,6 @@ class Context implements ContextInterface {
     return (bool) $this->contextValue || (bool) $this->getContextDefinition()->getDefaultValue();
   }
 
-  /**
-   * {@inheritdoc}
-   */
-  public function setContextDefinition(ContextDefinitionInterface $context_definition) {
-    $this->contextDefinition = $context_definition;
-  }
-
   /**
    * Implements \Drupal\Component\Plugin\Context\ContextInterface::getContextDefinition().
    */

core/lib/Drupal/Component/Plugin/Context/ContextInterface.php

@@ -12,16 +12,6 @@ namespace Drupal\Component\Plugin\Context;
  */
 interface ContextInterface {
 
-  /**
-   * Sets the context value.
-   *
-   * @param mixed $value
-   *   The value of this context, matching the context definition.
-   *
-   * @see \Drupal\Component\Plugin\Context\ContextInterface::setContextDefinition().
-   */
-  public function setContextValue($value);
-
   /**
    * Gets the context value.
    *
@@ -38,15 +28,6 @@ interface ContextInterface {
    */
   public function hasContextValue();
 
-  /**
-   * Sets the definition that the context must conform to.
-   *
-   * @param \Drupal\Component\Plugin\Context\ContextDefinitionInterface $context_definition
-   *   A defining characteristic representation of the context against which
-   *   that context can be validated.
-   */
-  public function setContextDefinition(ContextDefinitionInterface $context_definition);
-
   /**
    * Gets the provided definition that the context must conform to.
    *

core/lib/Drupal/Component/Plugin/ContextAwarePluginBase.php

@@ -41,17 +41,30 @@ abstract class ContextAwarePluginBase extends PluginBase implements ContextAware
    *   The plugin implementation definition.
    */
   public function __construct(array $configuration, $plugin_id, $plugin_definition) {
-    $context = array();
-    if (isset($configuration['context'])) {
-      $context = $configuration['context'];
-      unset($configuration['context']);
-    }
+    $context_configuration = isset($configuration['context']) ? $configuration['context'] : [];
+    unset($configuration['context']);
+
     parent::__construct($configuration, $plugin_id, $plugin_definition);
-    foreach ($context as $key => $value) {
+
+    $this->contexts = $this->createContextFromConfiguration($context_configuration);
+  }
+
+  /**
+   * Creates context objects from any context mappings in configuration.
+   *
+   * @param array $context_configuration
+   *   An associative array of context names and values.
+   *
+   * @return \Drupal\Component\Plugin\Context\ContextInterface[]
+   *   An array of context objects.
+   */
+  protected function createContextFromConfiguration(array $context_configuration) {
+    $contexts = [];
+    foreach ($context_configuration as $key => $value) {
       $context_definition = $this->getContextDefinition($key);
-      $this->context[$key] = new Context($context_definition);
-      $this->context[$key]->setContextValue($value);
+      $contexts[$key] = new Context($context_definition, $value);
     }
+    return $contexts;
   }
 
   /**
@@ -124,7 +137,7 @@ abstract class ContextAwarePluginBase extends PluginBase implements ContextAware
    * {@inheritdoc}
    */
   public function setContextValue($name, $value) {
-    $this->getContext($name)->setContextValue($value);
+    $this->context[$name] = new Context($this->getContextDefinition($name), $value);
     return $this;
   }
 

core/lib/Drupal/Component/Plugin/Definition/PluginDefinitionInterface.php

@@ -0,0 +1,40 @@
+<?php
+
+/**
+ * @file
+ * Contains \Drupal\Component\Plugin\PluginDefinitionInterface.
+ */
+
+namespace Drupal\Component\Plugin\Definition;
+
+/**
+ * Defines a plugin definition.
+ *
+ * Object-based plugin definitions MUST implement this interface.
+ *
+ * @ingroup Plugin
+ */
+interface PluginDefinitionInterface {
+
+  /**
+   * Sets the class.
+   *
+   * @param string $class
+   *   A fully qualified class name.
+   *
+   * @return static
+   *
+   * @throws \InvalidArgumentException
+   *   If the class is invalid.
+   */
+  public function setClass($class);
+
+  /**
+   * Gets the class.
+   *
+   * @return string
+   *   A fully qualified class name.
+   */
+  public function getClass();
+
+}

core/lib/Drupal/Component/Plugin/Factory/DefaultFactory.php

@@ -6,6 +6,7 @@
 
 namespace Drupal\Component\Plugin\Factory;
 
+use Drupal\Component\Plugin\Definition\PluginDefinitionInterface;
 use Drupal\Component\Plugin\Discovery\DiscoveryInterface;
 use Drupal\Component\Plugin\Exception\PluginException;
 
@@ -63,7 +64,7 @@ class DefaultFactory implements FactoryInterface {
    *
    * @param string $plugin_id
    *   The id of a plugin.
-   * @param mixed $plugin_definition
+   * @param \Drupal\Component\Plugin\Definition\PluginDefinitionInterface|mixed[] $plugin_definition
    *   The plugin definition associated with the plugin ID.
    * @param string $required_interface
    *   (optional) THe required plugin interface.
@@ -77,18 +78,32 @@ class DefaultFactory implements FactoryInterface {
    *
    */
   public static function getPluginClass($plugin_id, $plugin_definition = NULL, $required_interface = NULL) {
-    if (empty($plugin_definition['class'])) {
-      throw new PluginException(sprintf('The plugin (%s) did not specify an instance class.', $plugin_id));
-    }
+    $missing_class_message = sprintf('The plugin (%s) did not specify an instance class.', $plugin_id);
+    if (is_array($plugin_definition)) {
+      if (empty($plugin_definition['class'])) {
+        throw new PluginException($missing_class_message);
+      }
 
-    $class = $plugin_definition['class'];
+      $class = $plugin_definition['class'];
+    }
+    elseif ($plugin_definition instanceof PluginDefinitionInterface) {
+      if (!$plugin_definition->getClass()) {
+        throw new PluginException($missing_class_message);
+      }
+
+      $class = $plugin_definition->getClass();
+    }
+    else {
+      $plugin_definition_type = is_object($plugin_definition) ? get_class($plugin_definition) : gettype($plugin_definition);
+      throw new PluginException(sprintf('%s can only handle plugin definitions that are arrays or that implement %s, but %s given.', __CLASS__, PluginDefinitionInterface::class, $plugin_definition_type));
+    }
 
     if (!class_exists($class)) {
       throw new PluginException(sprintf('Plugin (%s) instance class "%s" does not exist.', $plugin_id, $class));
     }
 
-    if ($required_interface && !is_subclass_of($plugin_definition['class'], $required_interface)) {
-      throw new PluginException(sprintf('Plugin "%s" (%s) must implement interface %s.', $plugin_id, $plugin_definition['class'], $required_interface));
+    if ($required_interface && !is_subclass_of($class, $required_interface)) {
+      throw new PluginException(sprintf('Plugin "%s" (%s) must implement interface %s.', $plugin_id, $class, $required_interface));
     }
 
     return $class;