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

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

@@ -0,0 +1,31 @@
+<?php
+
+/**
+ * @file
+ * Contains \Drupal\Component\Plugin\DerivativeInspectionInterface.
+ */
+
+namespace Drupal\Component\Plugin;
+
+/**
+ * Provides a plugin interface for providing derivative metadata inspection.
+ */
+interface DerivativeInspectionInterface {
+
+  /**
+   * Gets the base_plugin_id of the plugin instance.
+   *
+   * @return string
+   *   The base_plugin_id of the plugin instance.
+   */
+  public function getBaseId();
+
+  /**
+   * Gets the derivative_id of the plugin instance.
+   *
+   * @return string|null
+   *   The derivative_id of the plugin instance NULL otherwise.
+   */
+  public function getDerivativeId();
+
+}