From 0f5d459ed8c0c1df7d9669c6112b6840bae3e50f Mon Sep 17 00:00:00 2001
From: Alexander Ljungberg <aljungberg@slevenbits.com>
Date: Tue, 23 Oct 2012 11:21:42 +0100
Subject: [PATCH] Fixed: collection view crash on unepexted drag events.

---
 AppKit/CPCollectionView.j | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/AppKit/CPCollectionView.j b/AppKit/CPCollectionView.j
index 813b4573d..e1c934f4c 100644
--- a/AppKit/CPCollectionView.j
+++ b/AppKit/CPCollectionView.j
@@ -690,6 +690,10 @@
 
 - (void)mouseDragged:(CPEvent)anEvent
 {
+    // Don't crash if we never registered the intial click.
+    if (!_mouseDownEvent)
+        return;
+
     var locationInWindow = [anEvent locationInWindow],
         mouseDownLocationInWindow = [_mouseDownEvent locationInWindow];