Tests, example change, and Util addition, plus usage in Tile/Image to allow

use of relative URLs, urls with port 80 in them, etc. patch originally from
tschaub, revised by euzuro, reviewed by me. 


git-svn-id: http://svn.openlayers.org/trunk/openlayers@2093 dc9f47b5-9b13-0410-9fdd-eb0c1a62fdaf

lib/OpenLayers/Util.js

@@ -709,3 +709,112 @@ OpenLayers.Util.pagePosition = function(forElement) {
 
     return [valueL, valueT];
 };
+
+
+/** Test two URLs for equivalence. 
+ * 
+ * Setting 'ignoreCase' allows for case-independent comparison.
+ * 
+ * Comparison is based on: 
+ *  - Protocol
+ *  - Host (evaluated without the port)
+ *  - Port (set 'ignorePort80' to ignore "80" values)
+ *  - Hash ( set 'ignoreHash' to disable)
+ *  - Pathname (for relative <-> absolute comparison) 
+ *  - Arguments (so they can be out of order)
+ *  
+ * 
+ *
+ * @param {String} url1
+ * @param {String} url2
+ * @param {Object} options allows for customization of comparison:
+ *                         'ignoreCase' - Default is True
+ *                         'ignorePort80' - Default is True
+ *                         'ignoreHash' - Default is True
+ *
+ * @returns Whether or not the two URLs are equivalent
+ * @type Boolean
+ */
+OpenLayers.Util.isEquivalentUrl = function(url1, url2, options) {
+    options = options || new Object();
+
+    OpenLayers.Util.applyDefaults(options, {
+        ignoreCase: true,
+        ignorePort80: true,
+        ignoreHash: true
+    });
+
+    urlObj1 = OpenLayers.Util.createUrlObject(url1, options);
+    urlObj2 = OpenLayers.Util.createUrlObject(url2, options);
+
+    //compare keys (host, port, etc)
+    for(var key in urlObj1) {
+        if ( (key != "args") && (urlObj1[key] != urlObj2[key]) ) {
+            return false;
+        }
+    }
+
+    // compare search args - irrespective of order
+    for(var key in urlObj1.args) {
+        if(urlObj1.args[key] != urlObj2.args[key]) {
+            return false;
+        }
+        delete urlObj2.args[key];
+    }
+    // urlObj2 shouldn't have any args left
+    for(var key in urlObj2.args) {
+        return false;
+    }
+    
+    return true;
+};
+
+/**
+ * @private
+ *
+ * @param {String} url
+ * @param {Object} options
+ * 
+ * @returns An object with separate url, a, port, host, and args parsed out 
+ *            and ready for comparison
+ * @type Object
+ */
+OpenLayers.Util.createUrlObject = function(url, options) {
+    options = options || new Object();
+
+    var urlObject = new Object();
+  
+    if (options.ignoreCase) {
+        url = url.toLowerCase(); 
+    }
+
+    var a = document.createElement('a');
+
+    a.href = url;
+    
+  //protocol
+    urlObject.protocol = a.protocol;  
+  
+  //pathname (this part allows for relative <-> absolute comparison)
+    urlObject.pathname = a.pathname;  
+    
+  //hash
+    urlObject.hash = (options.ignoreHash) ? "" : a.hash;  
+    
+  //host (without port)
+    urlObject.host = a.host;
+    var port = a.port;
+    if (port.length <= 0) {
+        var newHostLength = urlObject.host.length - (port.length);
+        urlObject.host = urlObject.host.substring(0, newHostLength); 
+    }
+    
+  //port
+    urlObject.port = ((port == "80") && (options.ignorePort80)) ? "" : port;
+                                                                     
+  //args
+    urlObject.args = OpenLayers.Util.getArgs(a.search);
+
+    return urlObject; 
+};
+