Adding Field.xpath_search method with the XPath to all Webrat fields

lib/webrat/core/field.rb

@@ -10,6 +10,10 @@ module Webrat
   class Field #:nodoc:
     attr_reader :value
     
+    def self.xpath_search
+      [".//button", ".//input", ".//textarea", ".//select"]
+    end
+    
     def initialize(form, element)
       @form     = form
       @element  = element

lib/webrat/core/locators.rb

@@ -53,7 +53,7 @@ module Webrat
     end
     
     def find_field_with_id(id, *field_types) #:nodoc:
-      field_elements = Webrat::XML.css_search(dom, "button", "input", "textarea", "select")
+      field_elements = Webrat::XML.xpath_search(dom, *Field.xpath_search)
       
       field_element = field_elements.detect do |field_element|
         if id.is_a?(Regexp)