Use document fragments to write multiple nodes

For writer functions that need to generate multiple nodes, the
createDocumentFragment method can be used.

lib/OpenLayers/Format/Filter/v1.js

@@ -281,19 +281,6 @@ OpenLayers.Format.Filter.v1 = OpenLayers.Class(OpenLayers.Format.XML, {
         return this.writers.ogc["Filter"].apply(this, [filter]);
     },
     
-    /**
-     * Method: writeFeatureIdNodes
-     * 
-     * Parameters:
-     * filter - {<OpenLayers.Filter.FeatureId}
-     * node - {DOMElement}
-     */
-    writeFeatureIdNodes: function(filter, node) {
-        for (var i=0, ii=filter.fids.length; i<ii; ++i) {
-            this.writeNode("FeatureId", filter.fids[i], node);
-        }
-    },
-    
     /**
      * Property: writers
      * As a compliment to the readers property, this structure contains public
@@ -304,10 +291,13 @@ OpenLayers.Format.Filter.v1 = OpenLayers.Class(OpenLayers.Format.XML, {
         "ogc": {
             "Filter": function(filter) {
                 var node = this.createElementNSPlus("ogc:Filter");
-                if (filter.type === "FID") {
+                this.writeNode(this.getFilterType(filter), filter, node);
-                    OpenLayers.Format.Filter.v1.prototype.writeFeatureIdNodes.call(this, filter, node);
+                return node;
-                } else {
+            },
-                    this.writeNode(this.getFilterType(filter), filter, node);
+            "_featureIds": function(filter) {
+                var node = this.createDocumentFragment();
+                for (var i=0, ii=filter.fids.length; i<ii; ++i) {
+                    this.writeNode("ogc:FeatureId", filter.fids[i], node);
                 }
                 return node;
             },
@@ -321,14 +311,10 @@ OpenLayers.Format.Filter.v1 = OpenLayers.Class(OpenLayers.Format.XML, {
                 var childFilter;
                 for (var i=0, ii=filter.filters.length; i<ii; ++i) {
                     childFilter = filter.filters[i];
-                    if (childFilter.type === "FID") {
-                        OpenLayers.Format.Filter.v1.prototype.writeFeatureIdNodes.call(this, childFilter, node);
-                    } else {
                     this.writeNode(
                         this.getFilterType(childFilter), childFilter, node
                     );
                 }
-                }
                 return node;
             },
             "Or": function(filter) {
@@ -336,26 +322,18 @@ OpenLayers.Format.Filter.v1 = OpenLayers.Class(OpenLayers.Format.XML, {
                 var childFilter;
                 for (var i=0, ii=filter.filters.length; i<ii; ++i) {
                     childFilter = filter.filters[i];
-                    if (childFilter.type === "FID") {
-                        OpenLayers.Format.Filter.v1.prototype.writeFeatureIdNodes.call(this, childFilter, node);
-                    } else {
                     this.writeNode(
                         this.getFilterType(childFilter), childFilter, node
                     );
                 }
-                }
                 return node;
             },
             "Not": function(filter) {
                 var node = this.createElementNSPlus("ogc:Not");
                 var childFilter = filter.filters[0];
-                if (childFilter.type === "FID") {
-                    OpenLayers.Format.Filter.v1.prototype.writeFeatureIdNodes.call(this, childFilter, node);
-                } else {
                 this.writeNode(
                     this.getFilterType(childFilter), childFilter, node
                 );
-                }
                 return node;
             },
             "PropertyIsLessThan": function(filter) {
@@ -498,7 +476,7 @@ OpenLayers.Format.Filter.v1 = OpenLayers.Class(OpenLayers.Format.XML, {
         "WITHIN": "WITHIN",
         "CONTAINS": "CONTAINS",
         "INTERSECTS": "INTERSECTS",
-        "FID": "FeatureId"
+        "FID": "_featureIds"
     },
 
     CLASS_NAME: "OpenLayers.Format.Filter.v1" 

lib/OpenLayers/Format/XML.js

@@ -230,6 +230,26 @@ OpenLayers.Format.XML = OpenLayers.Class(OpenLayers.Format, {
         return element;
     },
 
+    /**
+     * APIMethod: createDocumentFragment
+     * Create a document fragment node that can be appended to another node
+     *     created by createElementNS.  This will call 
+     *     document.createDocumentFragment outside of IE.  In IE, the ActiveX
+     *     object's createDocumentFragment method is used.
+     *
+     * Returns:
+     * {Element} A document fragment.
+     */
+    createDocumentFragment: function() {
+        var element;
+        if (this.xmldom) {
+            element = this.xmldom.createDocumentFragment();
+        } else {
+            element = document.createDocumentFragment();
+        }
+        return element;
+    },
+
     /**
      * APIMethod: createTextNode
      * Create a text node.  This node can be appended to another node with

tests/Format/XML.html

@@ -166,6 +166,35 @@
              "node can be appended to a doc root");
     }
 
+    function test_createDocumentFragment(t) {
+        t.plan(3);
+
+        var format = new OpenLayers.Format.XML();
+        var uri = "http://foo.com";
+        var prefix = "foo";
+        var localName = "bar";
+        var qualifiedName = prefix + ":" + localName;
+        var parent = format.createElementNS(uri, qualifiedName);
+
+        var fragment = format.createDocumentFragment();
+        t.eq(fragment.nodeType, 11, "fragment type");
+
+        try {
+            fragment.appendChild(format.createTextNode("one"));
+            fragment.appendChild(format.createTextNode("two"));
+            t.eq(fragment.childNodes.length, 2, "fragment has two child nodes");
+        } catch (err) {
+            t.fail("trouble appending text nodes to fragment: " + err.message);
+        }
+
+        try {
+            parent.appendChild(fragment);
+            t.eq(parent.childNodes.length, 2, "parent has two child nodes");
+        } catch (err) {
+            t.fail("trouble appending fragment to parent: " + err.message);
+        }
+    }
+
     function test_Format_XML_createTextNode(t) {
         t.plan(10);