Allow custom filters

lib/capybara/selector.rb

@@ -2,7 +2,7 @@ module Capybara
   class Selector
     PROPERTY_OPTION_KEYS = [:text, :visible, :with, :checked, :unchecked, :selected]
 
-    attr_reader :name
+    attr_reader :name, :custom_filters
 
     class Normalized
       attr_accessor :selector, :locator, :options, :xpath_options, :property_options, :xpaths
@@ -17,6 +17,9 @@ module Capybara
         return false if property_options[:checked]   and not node.checked?
         return false if property_options[:unchecked] and node.checked?
         return false if property_options[:selected]  and not has_selected_options?(node, property_options[:selected])
+        selector.custom_filters.each do |name, block|
+          return false if options.has_key?(name) and not block.call(node, options[name])
+        end
         true
       end
 
@@ -79,6 +82,7 @@ module Capybara
 
     def initialize(name, &block)
       @name = name
+      @custom_filters = {}
       instance_eval(&block)
     end
 
@@ -112,6 +116,10 @@ module Capybara
     def match?(locator)
       @match and @match.call(locator)
     end
+
+    def filter(name, &block)
+      @custom_filters[name] = block
+    end
   end
 end
 

lib/capybara/spec/session/find_spec.rb

@@ -107,6 +107,25 @@ shared_examples_for "find" do
       end
     end
 
+    context "with custom selector with custom filter", :focus => true do
+      before do
+        Capybara.add_selector(:monkey) do
+          xpath { |num| ".//*[contains(@id, 'monkey')][#{num}]" }
+          filter(:name) { |node, name| node.text == name }
+        end
+      end
+
+      it "should find elements that match the filter" do
+        @session.find(:monkey, '1', :name => 'Monkey John').text.should == 'Monkey John'
+        @session.find(:monkey, '2', :name => 'Monkey Paul').text.should == 'Monkey Paul'
+      end
+
+      it "should not find elements that don't match the filter" do
+        expect { @session.find(:monkey, '2', :name => 'Monkey John') }.to raise_error(Capybara::ElementNotFound)
+        expect { @session.find(:monkey, '1', :name => 'Monkey Paul') }.to raise_error(Capybara::ElementNotFound)
+      end
+    end
+
     context "with css as default selector" do
       before { Capybara.default_selector = :css }
       it "should find the first element using the given locator" do