From 17e56d83573740be6fc78a251b8cff04452f78b7 Mon Sep 17 00:00:00 2001
From: Guillaume Beraudo <guillaume.beraudo@camptocamp.com>
Date: Fri, 5 Dec 2014 14:55:46 +0100
Subject: [PATCH] Introduce clear event on vector source

Three seconds speed up when clearing 100'000 features.
Clearing is now around 350ms.
---
 src/ol/source/vectorsource.js            | 25 ++++++++++++++++++------
 test/spec/ol/source/vectorsource.test.js |  8 ++++++--
 2 files changed, 25 insertions(+), 8 deletions(-)

diff --git a/src/ol/source/vectorsource.js b/src/ol/source/vectorsource.js
index 6b223026a0..7551565165 100644
--- a/src/ol/source/vectorsource.js
+++ b/src/ol/source/vectorsource.js
@@ -37,7 +37,14 @@ ol.source.VectorEventType = {
   CHANGEFEATURE: 'changefeature',
 
   /**
-   * Triggered when a feature is removed from the source.
+   * Triggered when a clear is called on the source.
+   * @event ol.source.VectorEvent#clear
+   * @api
+   */
+  CLEAR: 'clear',
+
+  /**
+   * Triggered when a single feature is removed from the source.
    * @event ol.source.VectorEvent#removefeature
    * @api stable
    */
@@ -230,12 +237,18 @@ ol.source.Vector.prototype.addFeaturesInternal = function(features) {
  * @api stable
  */
 ol.source.Vector.prototype.clear = function() {
-  this.rBush_.forEach(this.removeFeatureInternal, this);
+  for (var featureId in this.featureChangeKeys_) {
+    var keys = this.featureChangeKeys_[featureId];
+    goog.array.forEach(keys, goog.events.unlistenByKey);
+  }
+  this.featureChangeKeys_ = {};
+  this.idIndex_ = {};
+  this.undefIdIndex_ = {};
   this.rBush_.clear();
-  goog.object.forEach(
-      this.nullGeometryFeatures_, this.removeFeatureInternal, this);
-  goog.object.clear(this.nullGeometryFeatures_);
-  goog.asserts.assert(goog.object.isEmpty(this.featureChangeKeys_));
+  this.nullGeometryFeatures_ = {};
+
+  var clearEvent = new ol.source.VectorEvent(ol.source.VectorEventType.CLEAR);
+  this.dispatchEvent(clearEvent);
   this.changed();
 };
 
diff --git a/test/spec/ol/source/vectorsource.test.js b/test/spec/ol/source/vectorsource.test.js
index 1ec5803a2c..e632efae11 100644
--- a/test/spec/ol/source/vectorsource.test.js
+++ b/test/spec/ol/source/vectorsource.test.js
@@ -90,13 +90,17 @@ describe('ol.source.Vector', function() {
         goog.events.listen(vectorSource, 'change', changeSpy);
         var removeFeatureSpy = sinon.spy();
         goog.events.listen(vectorSource, 'removefeature', removeFeatureSpy);
+        var clearSourceSpy = sinon.spy();
+        goog.events.listen(vectorSource, 'clear', clearSourceSpy);
         vectorSource.clear();
         expect(vectorSource.getFeatures()).to.eql([]);
         expect(vectorSource.isEmpty()).to.be(true);
         expect(changeSpy).to.be.called();
         expect(changeSpy.callCount).to.be(1);
-        expect(removeFeatureSpy).to.be.called();
-        expect(removeFeatureSpy.callCount).to.be(features.length);
+        expect(removeFeatureSpy).not.to.be.called();
+        expect(removeFeatureSpy.callCount).to.be(0);
+        expect(clearSourceSpy).to.be.called();
+        expect(clearSourceSpy.callCount).to.be(1);
       });
 
     });