From 1b46f38696a04239841505e45dc25c6cbf06d665 Mon Sep 17 00:00:00 2001
From: Andreas Hocevar <andreas.hocevar@gmail.com>
Date: Sat, 29 Jul 2017 23:10:53 +0200
Subject: [PATCH] Do not use Array.prototype.forEach for potentially large
 arrays

---
 src/ol/collection.js                  | 6 +++++-
 src/ol/format/wfs.js                  | 6 ++++--
 src/ol/renderer/canvas/vectorlayer.js | 6 ++++--
 3 files changed, 13 insertions(+), 5 deletions(-)

diff --git a/src/ol/collection.js b/src/ol/collection.js
index d168cb7d16..fda49e5f36 100644
--- a/src/ol/collection.js
+++ b/src/ol/collection.js
@@ -95,7 +95,11 @@ ol.Collection.prototype.extend = function(arr) {
  * @api
  */
 ol.Collection.prototype.forEach = function(f, opt_this) {
-  this.array_.forEach(f, opt_this);
+  var fn = (opt_this) ? f.bind(opt_this) : f;
+  var array = this.array_;
+  for (var i = 0, ii = array.length; i < ii; ++i) {
+    fn(array[i], i, array);
+  }
 };
 
 
diff --git a/src/ol/format/wfs.js b/src/ol/format/wfs.js
index ddd38dc2be..a30a9fe3d8 100644
--- a/src/ol/format/wfs.js
+++ b/src/ol/format/wfs.js
@@ -688,12 +688,14 @@ ol.format.WFS.writeDuringFilter_ = function(node, filter, objectStack) {
 ol.format.WFS.writeLogicalFilter_ = function(node, filter, objectStack) {
   /** @type {ol.XmlNodeStackItem} */
   var item = {node: node};
-  filter.conditions.forEach(function(condition) {
+  var conditions = filter.conditions;
+  for (var i = 0, ii = conditions.length; i < ii; ++i) {
+    var condition = conditions[i];
     ol.xml.pushSerializeAndPop(item,
         ol.format.WFS.GETFEATURE_SERIALIZERS_,
         ol.xml.makeSimpleNodeFactory(condition.getTagName()),
         [condition], objectStack);
-  });
+  }
 };
 
 
diff --git a/src/ol/renderer/canvas/vectorlayer.js b/src/ol/renderer/canvas/vectorlayer.js
index 55471f16b8..73491e8525 100644
--- a/src/ol/renderer/canvas/vectorlayer.js
+++ b/src/ol/renderer/canvas/vectorlayer.js
@@ -319,7 +319,7 @@ ol.renderer.canvas.VectorLayer.prototype.prepareFrame = function(frameState, lay
           feature, resolution, pixelRatio, styles, replayGroup);
       this.dirty_ = this.dirty_ || dirty;
     }
-  };
+  }.bind(this);
   if (vectorLayerRenderOrder) {
     /** @type {Array.<ol.Feature>} */
     var features = [];
@@ -331,7 +331,9 @@ ol.renderer.canvas.VectorLayer.prototype.prepareFrame = function(frameState, lay
           features.push(feature);
         }, this);
     features.sort(vectorLayerRenderOrder);
-    features.forEach(renderFeature, this);
+    for (var i = 0, ii = features.length; i < ii; ++i) {
+      renderFeature(features[i]);
+    }
   } else {
     vectorSource.forEachFeatureInExtent(extent, renderFeature, this);
   }