From a2b81d6bd0a4d0b2a9004baaa8a2854115abf99b Mon Sep 17 00:00:00 2001
From: Tim Schaub <tim.schaub@gmail.com>
Date: Tue, 20 May 2014 10:05:47 -0600
Subject: [PATCH] Disallow adding the same feature twice

---
 src/ol/source/vectorsource.js            |  9 ++++++---
 test/spec/ol/source/vectorsource.test.js | 15 +++++++++++++++
 2 files changed, 21 insertions(+), 3 deletions(-)

diff --git a/src/ol/source/vectorsource.js b/src/ol/source/vectorsource.js
index 50a7eca76b..03b4ffb3b6 100644
--- a/src/ol/source/vectorsource.js
+++ b/src/ol/source/vectorsource.js
@@ -128,15 +128,18 @@ ol.source.Vector.prototype.addFeatureInternal = function(feature) {
     var extent = geometry.getExtent();
     this.rBush_.insert(extent, feature);
   } else {
-    this.nullGeometryFeatures_[goog.getUid(feature).toString()] = feature;
+    this.nullGeometryFeatures_[featureKey] = feature;
   }
   var id = feature.getId();
   if (goog.isDef(id)) {
     var sid = id.toString();
-    goog.asserts.assert(!(goog.isDef(this.idIndex_[sid])));
+    goog.asserts.assert(!(sid in this.idIndex_),
+        'Feature with same id already added to the source: ' + id);
     this.idIndex_[sid] = feature;
   } else {
-    this.undefIdIndex_[goog.getUid(feature).toString()] = feature;
+    goog.asserts.assert(!(featureKey in this.undefIdIndex_),
+        'Feature already added to the source');
+    this.undefIdIndex_[featureKey] = feature;
   }
   this.dispatchEvent(
       new ol.source.VectorEvent(ol.source.VectorEventType.ADDFEATURE, feature));
diff --git a/test/spec/ol/source/vectorsource.test.js b/test/spec/ol/source/vectorsource.test.js
index 3777c1fd83..8957fd2305 100644
--- a/test/spec/ol/source/vectorsource.test.js
+++ b/test/spec/ol/source/vectorsource.test.js
@@ -363,6 +363,21 @@ describe('ol.source.Vector', function() {
 
   });
 
+  describe('the undefined feature id index', function() {
+    var source;
+    beforeEach(function() {
+      source = new ol.source.Vector();
+    });
+
+    it('disallows adding the same feature twice', function() {
+      var feature = new ol.Feature();
+      source.addFeature(feature);
+      expect(function() {
+        source.addFeature(feature);
+      }).to.throwException();
+    });
+  });
+
 });