add laravel 5.2 compatibility

Author: freekmurze

CHANGELOG.md

@@ -2,6 +2,9 @@
 
 All Notable changes to `activitylog` will be documented in this file
 
+### 2.3.0
+- Add compatibility with Laravel 5.2
+
 ### 2.2.1
 - Use database_path
 

src/Spatie/Activitylog/Models/Activity.php

@@ -4,6 +4,7 @@
 
 use Eloquent;
 use Config;
+use Exception;
 
 class Activity extends Eloquent
 {
@@ -21,7 +22,22 @@ class Activity extends Eloquent
      */
     public function user()
     {
-        return $this->belongsTo(Config::get('auth.model'), 'user_id');
+        return $this->belongsTo($this->getAuthModelName(), 'user_id');
+    }
+
+    public function getAuthModelName()
+    {
+        //laravel 5.0 - 5.1
+        if (! is_null(config('auth.model'))) {
+            return config('auth.model');
+        }
+
+        //laravel 5.2
+        if (! is_null(config('auth.providers.users.model'))) {
+            return config('auth.providers.users.model');
+        }
+
+        throw new Exception('could not determine the model name for users');
     }
 
     protected $guarded = ['id'];