add Vector.destroyFeatures() and call it from WFS.moveTo(), which keeps WFS

from loading the same set of features multiple times. Includes tests. fixes
#622.



git-svn-id: http://svn.openlayers.org/trunk/openlayers@2996 dc9f47b5-9b13-0410-9fdd-eb0c1a62fdaf

lib/OpenLayers/Layer/Vector.js

@@ -262,6 +262,14 @@ OpenLayers.Layer.Vector.prototype =
         }
     },
 
+    /**
+     */
+    destroyFeatures: function () {
+        for (var i = this.features.length - 1; i >= 0; i--) {
+            this.features[i].destroy();
+        }
+    },
+
     /**
      * @param {String} fid
      * @param {Object} style

lib/OpenLayers/Layer/WFS.js

@@ -188,6 +188,7 @@ OpenLayers.Layer.WFS.prototype =
                 this.tile.draw();
             } else {
                 if (this.vectorMode) {
+                    this.destroyFeatures();
                     this.renderer.clear();
                 } else {
                     this.clearMarkers();

tests/Layer/test_Vector.html

@@ -45,7 +45,7 @@
         t.ok(layer.features.length == 1, "OpenLayers.Layer.Vector.removeFeatures removes a feature from the features array");
     }
     
-    function test_Layer_Vector_addsStyle (t) {
+    function test_Layer_Vector_addStyle (t) {
         t.plan(2);    
         layer = new OpenLayers.Layer.Vector(name);
         var map = new OpenLayers.Map('map');
@@ -56,6 +56,22 @@
         t.ok( f.style != null, "Feature style is set by layer.");
     }
 
+    function test_Layer_Vector_destroyFeatures (t) {
+        t.plan(2); 
+        layer = new OpenLayers.Layer.Vector(name);
+        var map = new OpenLayers.Map('map');
+        map.addLayer(layer);
+        var features = [];
+        for (var i = 0; i < 5; i++) {
+            features.push(new OpenLayers.Feature.Vector(
+                          new OpenLayers.Geometry.Point(0,0)));
+        }
+        layer.addFeatures(features);
+        t.eq(layer.features.length, 5, "addFeatures adds 5 features");
+        layer.destroyFeatures();
+        t.eq(layer.features.length, 0, "destroyFeatures triggers removal");
+    }
+
     function test_99_Layer_Vector_destroy (t) {
         t.plan(1);    
         layer = new OpenLayers.Layer.Vector(name);