From 9e11ebb62a78140a75f29189849f9c02bedbea1f Mon Sep 17 00:00:00 2001
From: John-David Dalton <john.david.dalton@gmail.com>
Date: Thu, 3 Mar 2016 22:46:23 -0800
Subject: [PATCH] Ensure `_.isPlainObject` returns `false` for objects with a
 custom `[[Prototype]]`. [closes #2085]

---
 lodash.js    |  2 +-
 test/test.js | 12 ++++++++++++
 2 files changed, 13 insertions(+), 1 deletion(-)

diff --git a/lodash.js b/lodash.js
index a89ca30e7..0eae095ec 100644
--- a/lodash.js
+++ b/lodash.js
@@ -10607,7 +10607,7 @@
       if (proto === null) {
         return true;
       }
-      var Ctor = proto.constructor;
+      var Ctor = hasOwnProperty.call(proto, 'constructor') && proto.constructor;
       return (typeof Ctor == 'function' &&
         Ctor instanceof Ctor && funcToString.call(Ctor) == objectCtorString);
     }
diff --git a/test/test.js b/test/test.js
index 5b1a2e6c0..b4096c13f 100644
--- a/test/test.js
+++ b/test/test.js
@@ -10856,6 +10856,18 @@
       }
     });
 
+    QUnit.test('should return `false` for objects with a custom `[[Prototype]]`', function(assert) {
+      assert.expect(1);
+
+      if (create) {
+        var object = create({ 'a': 1 });
+        assert.strictEqual(_.isPlainObject(object), false);
+      }
+      else {
+        skipAssert(assert);
+      }
+    });
+
     QUnit.test('should return `false` for DOM elements', function(assert) {
       assert.expect(1);