diff --git a/src/Illuminate/Database/Eloquent/Concerns/HasRelationships.php b/src/Illuminate/Database/Eloquent/Concerns/HasRelationships.php
index <HASH>..<HASH> 100644
--- a/src/Illuminate/Database/Eloquent/Concerns/HasRelationships.php
+++ b/src/Illuminate/Database/Eloquent/Concerns/HasRelationships.php
@@ -192,7 +192,7 @@ trait HasRelationships
      */
     public static function getActualClassNameForMorph($class)
     {
-        return Arr::get(Relation::morphMap(), $class, $class);
+        return Arr::get(Relation::morphMap() ?: [], $class, $class);
     }
 
     /**
[<I>] Null Morph Map ErrorException (#<I>)

* [<I>] Null Morph Map ErrorException



Currently, if you call `getActualClassNameForMorph` without the morph map set, it will through an error because `Relation::morphMap()` returns `null` instead of (what I would expect) `[]`.



Is this expected behaviour? If so, why is this expected behaviour?



* Create HasRelationships.php