Refactor to reduce code duplication.

lib/geocoder/results/base.rb

@@ -20,8 +20,20 @@ module Geocoder
       ##
       # A string in the given format.
       #
+      # This default implementation dumbly follows the United States address
+      # format and will return incorrect results for most countries. Some APIs
+      # return properly formatted addresses and those should be funneled
+      # through this method.
+      #
       def address(format = :full)
-        fail
+        if state_code.to_s != ""
+          s = ", #{state_code}"
+        elsif state.to_s != ""
+          s = ", #{state}"
+        else
+          s = ""
+        end
+        "#{city}#{s} #{postal_code}, #{country}".sub(/^[ ,]*/, '')
       end
 
       ##

lib/geocoder/results/db_ip_com.rb

@@ -7,11 +7,6 @@ module Geocoder::Result
       ['latitude', 'longitude'].map{ |coordinate_name| @data[coordinate_name] }
     end
 
-    def address(format = :full)
-      s = state_code.to_s == "" ? "" : ", #{state_code}"
-      "#{city}#{s} #{zip_code}, #{country_name}".sub(/^[ ,]*/, "")
-    end
-
     def city
       @data['city']
     end

lib/geocoder/results/freegeoip.rb

@@ -3,11 +3,6 @@ require 'geocoder/results/base'
 module Geocoder::Result
   class Freegeoip < Base
 
-    def address(format = :full)
-      s = state_code.to_s == "" ? "" : ", #{state_code}"
-      "#{city}#{s} #{postal_code}, #{country}".sub(/^[ ,]*/, "")
-    end
-
     def city
       @data['city']
     end

lib/geocoder/results/geoip2.rb

@@ -3,10 +3,6 @@ require 'geocoder/results/base'
 module Geocoder
   module Result
     class Geoip2 < Base
-      def address(format = :full)
-        s = state.to_s == '' ? '' : ", #{state_code}"
-        "#{city}#{s} #{postal_code}, #{country}".sub(/^[ ,]*/, '')
-      end
 
       def coordinates
         %w[latitude longitude].map do |l|

lib/geocoder/results/ipdata_co.rb

@@ -3,11 +3,6 @@ require 'geocoder/results/base'
 module Geocoder::Result
   class IpdataCo < Base
 
-    def address(format = :full)
-      s = state_code.to_s == "" ? "" : ", #{state_code}"
-      "#{city}#{s} #{postal_code}, #{country}".sub(/^[ ,]*/, "")
-    end
-
     def city
       @data['city']
     end

lib/geocoder/results/maxmind.rb

@@ -87,11 +87,6 @@ module Geocoder::Result
       [data_hash[:latitude].to_f, data_hash[:longitude].to_f]
     end
 
-    def address(format = :full)
-      s = state_code.to_s == "" ? "" : ", #{state_code}"
-      "#{city}#{s} #{postal_code}, #{country_code}".sub(/^[ ,]*/, "")
-    end
-
     def city
       data_hash[:city_name]
     end

lib/geocoder/results/maxmind_local.rb

@@ -3,11 +3,6 @@ require 'geocoder/results/base'
 module Geocoder::Result
   class MaxmindLocal < Base
 
-    def address(format = :full)
-      s = state.to_s == "" ? "" : ", #{state}"
-      "#{city}#{s} #{postal_code}, #{country}".sub(/^[ ,]*/, "")
-    end
-
     def coordinates
       [@data[:latitude], @data[:longitude]]
     end

lib/geocoder/results/telize.rb

@@ -3,11 +3,6 @@ require 'geocoder/results/base'
 module Geocoder::Result
   class Telize < Base
 
-    def address(format = :full)
-      s = state_code.to_s == "" ? "" : ", #{state_code}"
-      "#{city}#{s} #{postal_code}, #{country}".sub(/^[ ,]*/, "")
-    end
-
     def city
       @data['city']
     end