Composer\Script\Event should have access to originating event details

src/Composer/EventDispatcher/EventDispatcher.php

@@ -196,7 +196,9 @@ class EventDispatcher
                     }
 
                     try {
-                        $return = $this->dispatch($scriptName, new Script\Event($scriptName, $event->getComposer(), $event->getIO(), $event->isDevMode(), $args, $flags));
+                        $scriptEvent = new Script\Event($scriptName, $event->getComposer(), $event->getIO(), $event->isDevMode(), $args, $flags);
+                        $scriptEvent->setOriginatingEvent($event);
+                        $return = $this->dispatch($scriptName, $scriptEvent);
                     } catch (ScriptExecutionException $e) {
                         $this->io->writeError(sprintf('<error>Script %s was called via %s</error>', $callable, $event->getName()), true, IOInterface::QUIET);
                         throw $e;

src/Composer/Script/Event.php

@@ -39,6 +39,11 @@ class Event extends BaseEvent
      */
     private $devMode;
 
+  /**
+   * @var BaseEvent
+   */
+    private $originatingEvent;
+
     /**
      * Constructor.
      *
@@ -55,6 +60,7 @@ class Event extends BaseEvent
         $this->composer = $composer;
         $this->io = $io;
         $this->devMode = $devMode;
+        $this->originatingEvent = null;
     }
 
     /**
@@ -86,4 +92,27 @@ class Event extends BaseEvent
     {
         return $this->devMode;
     }
+
+    /**
+     * Set the originating event.
+     *
+     * @return \Composer\EventDispatcher\Event|null
+     */
+    public function getOriginatingEvent()
+    {
+      return $this->originatingEvent;
+    }
+
+  /**
+   * Get the originating event.
+   *
+   * @param \Composer\EventDispatcher\Event $event
+   * @return $this
+   */
+    public function setOriginatingEvent(BaseEvent $event)
+    {
+      $this->originatingEvent = $event;
+
+      return $this;
+    }
 }