feat: Creates PrioritizedListenerProviderInterface

For use in getting a lookup table of priorities and associated
listeners, optionally using identifiers for lookup.

Author: weierophinney

TODO-PSR-14.md

@@ -12,7 +12,7 @@
 - [ ] Listener provider implementation
   - [x] Create a `ListenerProvider` subnamespace
   - [x] Create a `ListenerProviderInterface` shim
-  - [ ] Create a `PrioritizedListenerProvider` interface extending the
+  - [x] Create a `PrioritizedListenerProvider` interface extending the
       `ListenerProviderInterface` and defining a
       `getListenersForEventByPriority($event, array $identifiers = []) : array<int, callable[]>` method.
   - [ ] Create a `PrioritizedListenerAttachmentInterface`, defining:

src/ListenerProvider/PrioritizedListenerProviderInterface.php

@@ -0,0 +1,20 @@
+<?php
+/**
+ * @see       https://github.com/zendframework/zend-eventmanager for the canonical source repository
+ * @copyright Copyright (c) 2019 Zend Technologies USA Inc. (https://www.zend.com)
+ * @license   https://github.com/zendframework/zend-eventmanager/blob/master/LICENSE.md New BSD License
+ */
+
+namespace Zend\EventManager\ListenerProvider;
+
+interface PrioritizedListenerProviderInterface extends ListenerProviderInterface
+{
+    /**
+     * @param object $event The event for which to retrieve listeners.
+     * @param string[] $identifiers For use with shared listener providers.
+     *     This argument is deprecated, and will be removed in version 4.0.
+     * @return array<int, callable[]> Returns a hash table of priorities with
+     *     the associated listeners for that priority.
+     */
+    public function getListenersForEventByPriority($event, array $identifiers = []);
+}