From f5a05606515fc4f1e2ecb6cc32566f8100d01923 Mon Sep 17 00:00:00 2001
From: Jonas Staudenmeir <mail@jonas-staudenmeir.de>
Date: Thu, 3 Jan 2019 12:23:50 +0100
Subject: [PATCH] Fix loadMissing() with duplicate relation names

---
 src/Illuminate/Database/Eloquent/Collection.php    | 10 +++++++---
 .../Database/EloquentCollectionLoadMissingTest.php | 14 ++++++++++++++
 2 files changed, 21 insertions(+), 3 deletions(-)

diff --git a/src/Illuminate/Database/Eloquent/Collection.php b/src/Illuminate/Database/Eloquent/Collection.php
index 72d2d8515473..d1405e8d18bc 100755
--- a/src/Illuminate/Database/Eloquent/Collection.php
+++ b/src/Illuminate/Database/Eloquent/Collection.php
@@ -118,10 +118,14 @@ public function loadMissing($relations)
                 $segments[count($segments) - 1] .= ':'.explode(':', $key)[1];
             }
 
-            $path = array_combine($segments, $segments);
+            $path = [];
+
+            foreach ($segments as $segment) {
+                $path[] = [$segment => $segment];
+            }
 
             if (is_callable($value)) {
-                $path[end($segments)] = $value;
+                $path[count($segments) - 1][end($segments)] = $value;
             }
 
             $this->loadMissingRelation($this, $path);
@@ -139,7 +143,7 @@ public function loadMissing($relations)
      */
     protected function loadMissingRelation(Collection $models, array $path)
     {
-        $relation = array_splice($path, 0, 1);
+        $relation = array_shift($path);
 
         $name = explode(':', key($relation))[0];
 
diff --git a/tests/Integration/Database/EloquentCollectionLoadMissingTest.php b/tests/Integration/Database/EloquentCollectionLoadMissingTest.php
index db8f5c078dc5..c77527bde97c 100644
--- a/tests/Integration/Database/EloquentCollectionLoadMissingTest.php
+++ b/tests/Integration/Database/EloquentCollectionLoadMissingTest.php
@@ -43,6 +43,7 @@ public function setUp()
 
         Comment::create(['parent_id' => null, 'post_id' => 1]);
         Comment::create(['parent_id' => 1, 'post_id' => 1]);
+        Comment::create(['parent_id' => 2, 'post_id' => 1]);
 
         Revision::create(['comment_id' => 1]);
     }
@@ -75,6 +76,19 @@ public function testLoadMissingWithClosure()
         $this->assertTrue($posts[0]->comments[0]->relationLoaded('parent'));
         $this->assertArrayNotHasKey('post_id', $posts[0]->comments[1]->parent->getAttributes());
     }
+
+    public function testLoadMissingWithDuplicateRelationName()
+    {
+        $posts = Post::with('comments')->get();
+
+        DB::enableQueryLog();
+
+        $posts->loadMissing('comments.parent.parent');
+
+        $this->assertCount(2, DB::getQueryLog());
+        $this->assertTrue($posts[0]->comments[0]->relationLoaded('parent'));
+        $this->assertTrue($posts[0]->comments[1]->parent->relationLoaded('parent'));
+    }
 }
 
 class Comment extends Model