removes opt_this from ol.Collection#forEach

this commit also removes all uses of the standard thisArg of
Array#forEach.

changelog/upgrade-notes.md

@@ -35,6 +35,12 @@ register(proj4);
 
 The map and sources no longer accept a `logo` option.  Instead, if you wish to append a logo to your map, add the desired markup directly in your HTML.  In addition, you can use the `attributions` property of a source to display arbitrary markup per-source with the attribution control.
 
+#### Removal of optional this arguments.
+
+The following methods did get the optional this (i.e. opt_this) arguments removed. Please use closures, the es6 arrow function or the bind method to achieve this effect (Bind is explained here: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Function/bind).
+
+* ol.Collection#forEach
+
 ### v4.6.0
 
 #### Renamed `exceedLength` option of `ol.style.Text` to `overflow`

src/ol/Collection.js

@@ -101,18 +101,15 @@ _ol_Collection_.prototype.extend = function(arr) {
 
 /**
  * Iterate over each element, calling the provided callback.
- * @param {function(this: S, T, number, Array.<T>): *} f The function to call
+ * @param {function(T, number, Array.<T>): *} f The function to call
  *     for every element. This function takes 3 arguments (the element, the
  *     index and the array). The return value is ignored.
- * @param {S=} opt_this The object to use as `this` in `f`.
- * @template S
  * @api
  */
-_ol_Collection_.prototype.forEach = function(f, opt_this) {
-  var fn = (opt_this) ? f.bind(opt_this) : f;
+_ol_Collection_.prototype.forEach = function(f) {
   var array = this.array_;
   for (var i = 0, ii = array.length; i < ii; ++i) {
-    fn(array[i], i, array);
+    f(array[i], i, array);
   }
 };
 

src/ol/PluggableMap.js

@@ -357,7 +357,7 @@ var _ol_PluggableMap_ = function(options) {
        */
       function(control) {
         control.setMap(this);
-      }, this);
+      }.bind(this));
 
   _ol_events_.listen(this.controls, CollectionEventType.ADD,
       /**
@@ -382,7 +382,7 @@ var _ol_PluggableMap_ = function(options) {
        */
       function(interaction) {
         interaction.setMap(this);
-      }, this);
+      }.bind(this));
 
   _ol_events_.listen(this.interactions, CollectionEventType.ADD,
       /**
@@ -400,7 +400,7 @@ var _ol_PluggableMap_ = function(options) {
         event.element.setMap(null);
       }, this);
 
-  this.overlays_.forEach(this.addOverlayInternal_, this);
+  this.overlays_.forEach(this.addOverlayInternal_.bind(this));
 
   _ol_events_.listen(this.overlays_, CollectionEventType.ADD,
       /**

src/ol/control/OverviewMap.js

@@ -129,7 +129,7 @@ var OverviewMap = function(opt_options) {
        */
         function(layer) {
           ovmap.addLayer(layer);
-        }, this);
+        }.bind(this));
   }
 
   var box = document.createElement('DIV');

src/ol/interaction/Modify.js

@@ -213,7 +213,7 @@ var _ol_interaction_Modify_ = function(options) {
    */
   this.features_ = features;
 
-  this.features_.forEach(this.addFeature_, this);
+  this.features_.forEach(this.addFeature_.bind(this));
   _ol_events_.listen(this.features_, CollectionEventType.ADD,
       this.handleFeatureAdd_, this);
   _ol_events_.listen(this.features_, CollectionEventType.REMOVE,

src/ol/interaction/Select.js

@@ -313,12 +313,12 @@ _ol_interaction_Select_.prototype.setMap = function(map) {
   var selectedFeatures =
       this.featureOverlay_.getSource().getFeaturesCollection();
   if (currentMap) {
-    selectedFeatures.forEach(currentMap.unskipFeature, currentMap);
+    selectedFeatures.forEach(currentMap.unskipFeature.bind(currentMap));
   }
   Interaction.prototype.setMap.call(this, map);
   this.featureOverlay_.setMap(map);
   if (map) {
-    selectedFeatures.forEach(map.skipFeature, map);
+    selectedFeatures.forEach(map.skipFeature.bind(map));
   }
 };
 

src/ol/interaction/Snap.js

@@ -302,7 +302,7 @@ _ol_interaction_Snap_.prototype.setMap = function(map) {
   if (currentMap) {
     keys.forEach(_ol_events_.unlistenByKey);
     keys.length = 0;
-    features.forEach(this.forEachFeatureRemove_, this);
+    features.forEach(this.forEachFeatureRemove_.bind(this));
   }
   _ol_interaction_Pointer_.prototype.setMap.call(this, map);
 
@@ -322,7 +322,7 @@ _ol_interaction_Snap_.prototype.setMap = function(map) {
               this.handleFeatureRemove_, this)
       );
     }
-    features.forEach(this.forEachFeatureAdd_, this);
+    features.forEach(this.forEachFeatureAdd_.bind(this));
   }
 };
 
@@ -613,7 +613,7 @@ _ol_interaction_Snap_.handleEvent_ = function(evt) {
 _ol_interaction_Snap_.handleUpEvent_ = function(evt) {
   var featuresToUpdate = _ol_obj_.getValues(this.pendingFeatures_);
   if (featuresToUpdate.length) {
-    featuresToUpdate.forEach(this.updateFeature_, this);
+    featuresToUpdate.forEach(this.updateFeature_.bind(this));
     this.pendingFeatures_ = {};
   }
   return false;

src/ol/pointer/PointerEventHandler.js

@@ -122,7 +122,7 @@ _ol_pointer_PointerEventHandler_.prototype.registerSource = function(name, sourc
       if (handler) {
         this.eventMap_[e] = handler.bind(s);
       }
-    }, this);
+    }.bind(this));
     this.eventSourceList_.push(s);
   }
 };
@@ -178,7 +178,7 @@ _ol_pointer_PointerEventHandler_.prototype.eventHandler_ = function(inEvent) {
 _ol_pointer_PointerEventHandler_.prototype.addEvents_ = function(events) {
   events.forEach(function(eventName) {
     _ol_events_.listen(this.element_, eventName, this.eventHandler_, this);
-  }, this);
+  }.bind(this));
 };
 
 
@@ -190,7 +190,7 @@ _ol_pointer_PointerEventHandler_.prototype.addEvents_ = function(events) {
 _ol_pointer_PointerEventHandler_.prototype.removeEvents_ = function(events) {
   events.forEach(function(e) {
     _ol_events_.unlisten(this.element_, e, this.eventHandler_, this);
-  }, this);
+  }.bind(this));
 };
 
 

src/ol/renderer/webgl/VectorLayer.js

@@ -292,7 +292,7 @@ _ol_renderer_webgl_VectorLayer_.prototype.prepareFrame = function(frameState, la
           features.push(feature);
         }, this);
     features.sort(vectorLayerRenderOrder);
-    features.forEach(renderFeature, this);
+    features.forEach(renderFeature.bind(this));
   } else {
     vectorSource.forEachFeatureInExtent(extent, renderFeature, this);
   }

src/ol/reproj/Tile.js

@@ -222,7 +222,7 @@ _ol_reproj_Tile_.prototype.reproject_ = function() {
         image: tile.getImage()
       });
     }
-  }, this);
+  }.bind(this));
   this.sourceTiles_.length = 0;
 
   if (sources.length === 0) {
@@ -281,7 +281,7 @@ _ol_reproj_Tile_.prototype.load = function() {
             }, this);
         this.sourcesListenerKeys_.push(sourceListenKey);
       }
-    }, this);
+    }.bind(this));
 
     this.sourceTiles_.forEach(function(tile, i, arr) {
       var state = tile.getState();

src/ol/reproj/Triangulation.js

@@ -172,7 +172,7 @@ var _ol_reproj_Triangulation_ = function(sourceProj, targetProj, targetExtent,
           triangle.source = newTriangle;
         }
       }
-    }, this);
+    }.bind(this));
   }
 
   transformInvCache = {};

src/ol/source/Vector.js

@@ -390,7 +390,7 @@ _ol_source_Vector_.prototype.forEachFeature = function(callback, opt_this) {
   if (this.featuresRtree_) {
     return this.featuresRtree_.forEach(callback, opt_this);
   } else if (this.featuresCollection_) {
-    return this.featuresCollection_.forEach(callback, opt_this);
+    return this.featuresCollection_.forEach(callback.bind(opt_this));
   }
 };
 
@@ -446,7 +446,7 @@ _ol_source_Vector_.prototype.forEachFeatureInExtent = function(extent, callback,
   if (this.featuresRtree_) {
     return this.featuresRtree_.forEachInExtent(extent, callback, opt_this);
   } else if (this.featuresCollection_) {
-    return this.featuresCollection_.forEach(callback, opt_this);
+    return this.featuresCollection_.forEach(callback.bind(opt_this));
   }
 };
 

test/spec/ol/collection.test.js

@@ -106,17 +106,6 @@ describe('ol.collection', function() {
         expect(cb.callCount).to.eql(2);
       });
     });
-    describe('scope', function() {
-      it('callbacks get the correct scope', function() {
-        var collection = new _ol_Collection_([0]);
-        var that;
-        var uniqueObj = {};
-        collection.forEach(function(elem) {
-          that = this;
-        }, uniqueObj);
-        expect(that).to.be(uniqueObj);
-      });
-    });
   });
 
   describe('remove', function() {