Test handle method of an event listener

app/Listeners/LoginListener.php

@@ -22,10 +22,22 @@ public function __construct()
      * Handle the event.
      *
      * @param  \Illuminate\Auth\Events\Login  $event
-     * @return void
+     * @return mixed
      */
     public function handle(Login $event)
     {
-        logger("Logged in user: {$event->user->email}");
+        // Do your stuff
+
+        // logger("Logged in user: {$event->user->email}");
+
+        // For testing purpose only, in this case.
+        $this->doSomething();
+
+        // For testing purpose only, in this case.
+        return $event;
+    }
+
+    public function doSomething()
+    {
     }
 }

tests/Unit/ListenerTest.php

@@ -0,0 +1,38 @@
+<?php
+
+namespace Tests\Unit;
+
+
+use App\Listeners\LoginListener;
+use App\Models\User;
+use Illuminate\Auth\Events\Login;
+use Illuminate\Foundation\Testing\RefreshDatabase;
+use Tests\TestCase;
+
+class ListenerTest extends TestCase
+{
+    use RefreshDatabase;
+
+    /** @test */
+    public function handle_method_of_an_event_listener()
+    {
+        $user = User::factory()->create();
+
+        $login = new Login('web', $user, false);
+
+        $listener = $this->mock(LoginListener::class)->makePartial();
+
+        $listener->shouldReceive('doSomething')
+            ->once()
+            ->andReturnNull();
+
+        // Say, the handle() method is being called by the event API
+        $loginEvent = $listener->handle($login);
+
+        $this->assertSame('web', $loginEvent->guard);
+
+        $this->assertFalse($loginEvent->remember);
+
+        $this->assertSame($user->email, $loginEvent->user->email);
+    }
+}