Add scope to ol.Array.forEach

src/ol/array.js

@@ -104,10 +104,12 @@ ol.Array.prototype.clear = function() {
 
 
 /**
- * @param {function(*, number)} callback Callback.
+ * @param {function(this: T, *, number)} f Function.
+ * @param {T=} opt_obj The object to be used for the value of 'this' within f.
+ * @template T
  */
-ol.Array.prototype.forEach = function(callback) {
+ol.Array.prototype.forEach = function(f, opt_obj) {
-  goog.array.forEach(this.array_, callback);
+  goog.array.forEach(this.array_, f, opt_obj);
 };
 
 

src/ol/array_test.js

@@ -192,3 +192,24 @@ function testLengthChangeSetAt() {
   array.setAt(1, 1);
   assertUndefined(lengthChangedCalled);
 }
+
+
+function testForEach() {
+  var array = ol.Array.create([1, 2, 4]);
+  var sum = 0;
+  array.forEach(function(elem) {
+    sum += elem;
+  });
+  assertEquals(7, sum);
+}
+
+
+function testForEachScope() {
+  var array = ol.Array.create([0]);
+  var that;
+  var uniqueObj = {};
+  array.forEach(function(elem) {
+    that = this;
+  }, uniqueObj);
+  assertTrue(that === uniqueObj);
+}