Add a new extender interface for extension lifecycle hooks

framework/core/src/Extend/Formatter.php

@@ -11,15 +11,13 @@
 
 namespace Flarum\Extend;
 
-use Flarum\Extension\Event\Disabled;
-use Flarum\Extension\Event\Enabled;
 use Flarum\Extension\Extension;
 use Flarum\Formatter\Event\Configuring;
 use Flarum\Formatter\Formatter as ActualFormatter;
 use Illuminate\Contracts\Container\Container;
 use Illuminate\Events\Dispatcher;
 
-class Formatter implements ExtenderInterface
+class Formatter implements ExtenderInterface, LifecycleInterface
 {
     protected $callback;
 
@@ -40,16 +38,17 @@ class Formatter implements ExtenderInterface
                 call_user_func($this->callback, $event->configurator);
             }
         );
+    }
 
-        // Also set up an event listener to flush the formatter cache whenever
-        // this extension is enabled or disabled.
-        $events->listen(
-            [Enabled::class, Disabled::class],
-            function ($event) use ($container, $extension) {
-                if ($event->extension === $extension) {
-                    $container->make(ActualFormatter::class)->flush();
-                }
-            }
-        );
+    public function onEnable(Container $container, Extension $extension)
+    {
+        // FLush the formatter cache when this extension is enabled
+        $container->make(ActualFormatter::class)->flush();
+    }
+
+    public function onDisable(Container $container, Extension $extension)
+    {
+        // FLush the formatter cache when this extension is disabled
+        $container->make(ActualFormatter::class)->flush();
     }
 }

framework/core/src/Extend/LifecycleInterface.php

@@ -0,0 +1,22 @@
+<?php
+
+/*
+ * This file is part of Flarum.
+ *
+ * (c) Toby Zerner <toby.zerner@gmail.com>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Flarum\Extend;
+
+use Flarum\Extension\Extension;
+use Illuminate\Contracts\Container\Container;
+
+interface LifecycleInterface
+{
+    public function onEnable(Container $container, Extension $extension);
+
+    public function onDisable(Container $container, Extension $extension);
+}

framework/core/src/Extension/Extension.php

@@ -12,6 +12,7 @@
 namespace Flarum\Extension;
 
 use Flarum\Extend\Compat;
+use Flarum\Extend\LifecycleInterface;
 use Illuminate\Contracts\Container\Container;
 use Illuminate\Contracts\Support\Arrayable;
 use Illuminate\Support\Arr;
@@ -223,6 +224,24 @@ class Extension implements Arrayable
         return $icon;
     }
 
+    public function enable(Container $container)
+    {
+        $this->setEnabled(true);
+
+        foreach ($this->getLifecycleExtenders() as $extender) {
+            $extender->onEnable($container, $this);
+        }
+    }
+
+    public function disable(Container $container)
+    {
+        $this->setEnabled(false);
+
+        foreach ($this->getLifecycleExtenders() as $extender) {
+            $extender->onDisable($container, $this);
+        }
+    }
+
     /**
      * @param bool $enabled
      * @return Extension
@@ -277,6 +296,19 @@ class Extension implements Arrayable
         return array_flatten($extenders);
     }
 
+    /**
+     * @return LifecycleInterface[]
+     */
+    private function getLifecycleExtenders(): array
+    {
+        return array_filter(
+            $this->getExtenders(),
+            function ($extender) {
+                return $extender instanceof LifecycleInterface;
+            }
+        );
+    }
+
     private function getExtenderFile(): ?string
     {
         $filename = "{$this->path}/extend.php";

framework/core/src/Extension/ExtensionManager.php

@@ -128,7 +128,7 @@ class ExtensionManager
 
             $this->setEnabled($enabled);
 
-            $extension->setEnabled(true);
+            $extension->enable($this->app);
 
             $this->dispatcher->dispatch(new Enabled($extension));
         }
@@ -152,7 +152,7 @@ class ExtensionManager
 
             $this->setEnabled($enabled);
 
-            $extension->setEnabled(false);
+            $extension->disable($this->app);
 
             $this->dispatcher->dispatch(new Disabled($extension));
         }