Take 2. Fix failures of xpath with custom object. By this change, nam…

…espace for xpath function has been added to NokogiriNamespaceContext.

ext/java/nokogiri/XmlXpathContext.java

@@ -1,5 +1,7 @@
 package nokogiri;
 
+import java.util.Set;
+
 import nokogiri.internals.NokogiriNamespaceContext;
 import javax.xml.xpath.XPath;
 import javax.xml.xpath.XPathExpression;
@@ -36,6 +38,12 @@ public IRubyObject evaluate(ThreadContext context, IRubyObject expr, IRubyObject
         String src = expr.convertToString().asJavaString();
         try {
             if(!handler.isNil()) {
+            	if (!isContainsPrefix(src)) {
+                    Set<String> methodNames = handler.getMetaClass().getMethods().keySet();
+                    for (String name : methodNames) {
+                        src = src.replaceAll(name, NokogiriNamespaceContext.NOKOGIRI_PREFIX+":"+name);
+                    }
+                }
                 xpath.setXPathFunctionResolver(new NokogiriXPathFunctionResolver(handler));
             }
             XPathExpression xpathExpression = xpath.compile(src);
@@ -44,6 +52,17 @@ public IRubyObject evaluate(ThreadContext context, IRubyObject expr, IRubyObject
             throw new RaiseException(XmlSyntaxError.getXPathSyntaxError(context, xpee));
         }
     }
+
+    private boolean isContainsPrefix(String str) {
+        Set<String> prefixes = ((NokogiriNamespaceContext)xpath.getNamespaceContext()).getAllPrefixes();
+        for (String prefix : prefixes) {
+            if (str.contains(prefix + ":")) {
+                return true;
+            }
+        }
+        return false;
+    }
+
 
     @JRubyMethod
     public IRubyObject evaluate(ThreadContext context, IRubyObject expr) {

ext/java/nokogiri/internals/NokogiriNamespaceContext.java

@@ -1,49 +1,71 @@
 package nokogiri.internals;
 
+import java.util.ArrayList;
 import java.util.Hashtable;
 import java.util.Iterator;
+import java.util.List;
+import java.util.Set;
+import java.util.Map.Entry;
+
 import javax.xml.XMLConstants;
 import javax.xml.namespace.NamespaceContext;
 
-public class NokogiriNamespaceContext implements NamespaceContext{
-
-    Hashtable<String,String> register;
+public class NokogiriNamespaceContext implements NamespaceContext {
+	public static final String NOKOGIRI_PREFIX = "nokogiri";
+    public static final String NOKOGIRI_URI = "http://www.nokogiri.org/default_ns/ruby/extensions_functions";
+
+    private Hashtable<String,String> register;
 
-    public NokogiriNamespaceContext(){
+    public NokogiriNamespaceContext() {
         this.register = new Hashtable<String,String>();
+        register.put(NOKOGIRI_PREFIX, NOKOGIRI_URI);
     }
 
     public String getNamespaceURI(String prefix) {
-//        System.out.println("Asked for " + prefix);
+    	if (prefix == null) {
+            throw new IllegalArgumentException();
+        }
         String uri = this.register.get(prefix);
-        if(uri != null) {
-//            System.out.println("Returned "+uri);
+        if (uri != null) {
             return uri;
         }
 
-//        System.out.println("Returned another url");
-
-        if(prefix == null) {
-            throw new IllegalArgumentException();
-        } else if(prefix.equals(XMLConstants.XMLNS_ATTRIBUTE)) {
+        if (prefix.equals(XMLConstants.XMLNS_ATTRIBUTE)) {
             uri = this.register.get(XMLConstants.XMLNS_ATTRIBUTE);
             return (uri == null) ? XMLConstants.XMLNS_ATTRIBUTE_NS_URI : uri;
         }
 
         return XMLConstants.NULL_NS_URI;
     }
 
-    public String getPrefix(String uri){
+    public String getPrefix(String uri) {
+    	if (uri == null) {
+            throw new IllegalArgumentException("uri is null");
+        } else if (uri.equals(NOKOGIRI_URI)) {
+            return NOKOGIRI_PREFIX;
+        }
         return null;
     }
 
-    public Iterator getPrefixes(String uri){
-        return null;
+    public Iterator<String> getPrefixes(String uri) {
+        if (register == null) return null;
+        Set<Entry<String, String>> entries = register.entrySet();
+        List<String> list = new ArrayList<String>();
+        for (Entry<String, String> entry : entries) {
+            if (uri.equals(entry.getValue())) {
+                list.add(entry.getKey());
+            }
+        }
+        return list.iterator();
+    }
+
+    public Set<String> getAllPrefixes() {
+        if (register == null) return null;
+        return register.keySet();
     }
 
-    public void registerNamespace(String prefix, String uri){
+    public void registerNamespace(String prefix, String uri) {
         if("xmlns".equals(prefix)) prefix = "";
-//        System.out.println("Registered prefix "+prefix+" with uri " + uri);
         this.register.put(prefix, uri);
     }
 }