Add layerGroup#getLayers and tests. Fixes Leaflet#1460

Author: tmcw

spec/runner.html

@@ -47,6 +47,7 @@
 
 	<!-- /layer -->
 	<script type="text/javascript" src="suites/layer/FeatureGroupSpec.js"></script>
+	<script type="text/javascript" src="suites/layer/LayerGroupSpec.js"></script>
 	<script type="text/javascript" src="suites/layer/TileLayerSpec.js"></script>
 
 	<!-- /layer/vector/ -->

spec/suites/layer/LayerGroupSpec.js

@@ -0,0 +1,58 @@
+describe('LayerGroup', function () {
+	describe("#addLayer", function () {
+		it('adds a layer', function() {
+			var lg = L.layerGroup(),
+				marker = L.marker([0, 0]);
+
+			expect(lg.addLayer(marker)).toEqual(lg);
+
+			expect(lg.hasLayer(marker)).toBe(true);
+		});
+	});
+	describe("#removeLayer", function () {
+		it('removes a layer', function() {
+			var lg = L.layerGroup(),
+				marker = L.marker([0, 0]);
+
+			lg.addLayer(marker);
+			expect(lg.removeLayer(marker)).toEqual(lg);
+
+			expect(lg.hasLayer(marker)).toBe(false);
+		});
+	});
+	describe("#clearLayers", function () {
+		it('removes all layers', function() {
+			var lg = L.layerGroup(),
+				marker = L.marker([0, 0]);
+
+			lg.addLayer(marker);
+			expect(lg.clearLayers()).toEqual(lg);
+
+			expect(lg.hasLayer(marker)).toBe(false);
+		});
+	});
+	describe("#getLayers", function () {
+		it('gets all layers', function() {
+			var lg = L.layerGroup(),
+				marker = L.marker([0, 0]);
+
+			lg.addLayer(marker);
+
+			expect(lg.getLayers()).toEqual([marker]);
+		});
+	});
+	describe("#eachLayer", function () {
+		it('iterates over all layers', function() {
+			var lg = L.layerGroup(),
+				marker = L.marker([0, 0]),
+				ctx = { foo: 'bar' };
+
+			lg.addLayer(marker);
+
+			lg.eachLayer(function(layer) {
+				expect(layer).toEqual(marker);
+				expect(this).toEqual(ctx);
+			}, ctx);
+		});
+	});
+});

src/layer/LayerGroup.js

@@ -93,6 +93,16 @@ L.LayerGroup = L.Class.extend({
 		return this;
 	},
 
+	getLayers: function () {
+		var layers = [];
+		for (var i in this._layers) {
+			if (this._layers.hasOwnProperty(i)) {
+				layers.push(this._layers[i]);
+			}
+		}
+		return layers;
+	},
+
 	setZIndex: function (zIndex) {
 		return this.invoke('setZIndex', zIndex);
 	}