app/concerns/liquid_interpolatable.rb

@@ -26,12 +26,29 @@ module LiquidInterpolatable

                   end
              

                 
              

                   require 'uri'
              

                -  # Percent encoding for URI conforming to RFC 3986.
              

                -  # Ref: http://tools.ietf.org/html/rfc3986#page-12
              

                   module Filters
              

                +    # Percent encoding for URI conforming to RFC 3986.
              

                +    # Ref: http://tools.ietf.org/html/rfc3986#page-12
              

                     def uri_escape(string)
              

                       CGI::escape string
              

                     end
              

                +
              

                +    # Escape a string for use in XPath expression
              

                +    def to_xpath(string)
              

                +      subs = string.scan(/\G(?:\A\z|[^"]+|[^']+)/).map { |x|
              

                +        case x
              

                +        when /"/
              

                +          %Q{'#{x}'}
              

                +        else
              

                +          %Q{"#{x}"}
              

                +        end
              

                +      }
              

                +      if subs.size == 1
              

                +        subs.first
              

                +      else
              

                +        'concat(' << subs.join(', ') << ')'
              

                +      end
              

                +    end
              

                   end
              

                   Liquid::Template.register_filter(LiquidInterpolatable::Filters)
              

                 
              

spec/concerns/liquid_interpolatable_spec.rb

@@ -1,4 +1,5 @@

                 require 'spec_helper'
              

                +require 'nokogiri'
              

                 
              

                 describe LiquidInterpolatable::Filters do
              

                   before do
              
@@ -12,4 +13,21 @@ describe LiquidInterpolatable::Filters do

                       @filter.uri_escape('abc:/?=').should == 'abc%3A%2F%3F%3D'
              

                     end
              

                   end
              

                +
              

                +  describe 'to_xpath' do
              

                +    before do
              

                +      def @filter.to_xpath_roundtrip(string)
              

                +        Nokogiri::XML('').xpath(to_xpath(string))
              

                +      end
              

                +    end
              

                +
              

                +    it 'should escape a string for use in XPath expression' do
              

                +      [
              

                +        %q{abc}.freeze,
              

                +        %q{'a"bc'dfa""fds''fa}.freeze,
              

                +      ].each { |string|
              

                +        @filter.to_xpath_roundtrip(string).should == string
              

                +      }
              

                +    end
              

                +  end
              

                 end
              

spec/models/agents/website_agent_spec.rb

@@ -471,7 +471,7 @@ fire: hot

                 
              

                         lambda {
              

                           @valid_options['extract']['site_title'] = {
              

                -            'css' => "#comic img", 'value' => "'{{title}}'"
              

                +            'css' => "#comic img", 'value' => "{{title | to_xpath }}"
              

                           }
              

                           @checker.options = @valid_options
              

                           @checker.receive([@event])