From 49770eca4e2e780d4e8cdc762e2adbcab8b924fa Mon Sep 17 00:00:00 2001
From: Taylor Otwell <taylor@laravel.com>
Date: Mon, 5 Mar 2018 08:05:53 -0600
Subject: [PATCH] port change forward

---
 src/Illuminate/View/Concerns/ManagesLoops.php |  9 +++++++-
 tests/View/ViewFactoryTest.php                | 22 +++++++++++++++++++
 2 files changed, 30 insertions(+), 1 deletion(-)

diff --git a/src/Illuminate/View/Concerns/ManagesLoops.php b/src/Illuminate/View/Concerns/ManagesLoops.php
index 5f50b247efd9..ff3332c3802e 100644
--- a/src/Illuminate/View/Concerns/ManagesLoops.php
+++ b/src/Illuminate/View/Concerns/ManagesLoops.php
@@ -3,6 +3,7 @@
 namespace Illuminate\View\Concerns;
 
 use Countable;
+use Traversable;
 use Illuminate\Support\Arr;
 
 trait ManagesLoops
@@ -22,7 +23,13 @@ trait ManagesLoops
      */
     public function addLoop($data)
     {
-        $length = is_array($data) || $data instanceof Countable ? count($data) : null;
+        $length = null;
+
+        if (is_array($data) || $data instanceof Countable) {
+            $length = count($data);
+        } elseif ($data instanceof Traversable) {
+            $length = iterator_count($data);
+        }
 
         $parent = Arr::last($this->loopsStack);
 
diff --git a/tests/View/ViewFactoryTest.php b/tests/View/ViewFactoryTest.php
index efbccf85d3ea..b4e91ec5ab14 100755
--- a/tests/View/ViewFactoryTest.php
+++ b/tests/View/ViewFactoryTest.php
@@ -555,6 +555,28 @@ public function testAddingLoops()
         $this->assertEquals([$expectedLoop], $factory->getLoopStack());
     }
 
+    public function testAddingTraversableLoop()
+    {
+        $factory = $this->getFactory();
+
+        $data = new \DatePeriod(\Carbon\Carbon::today(), \Carbon\CarbonInterval::day(), \Carbon\Carbon::tomorrow()->endOfDay());
+
+        $factory->addLoop($data);
+
+        $expectedLoop = [
+            'iteration' => 0,
+            'index' => 0,
+            'remaining' => 2,
+            'count' => 2,
+            'first' => true,
+            'last' => false,
+            'depth' => 1,
+            'parent' => null,
+        ];
+
+        $this->assertEquals([$expectedLoop], $factory->getLoopStack());
+    }
+
     public function testAddingUncountableLoop()
     {
         $factory = $this->getFactory();