Use #first and #last rather than #[] for lat/lng pairs

ActiveRecord::Base responds to #[], as an alternate way of accessing
attributes (who knew?).

[sunspot#69 state:resolved]

sunspot/lib/sunspot/util.rb

@@ -187,8 +187,8 @@ def initialize(coords)
       end
 
       def lat
-        if @coords.respond_to?(:[])
-          @coords[0]
+        if @coords.respond_to?(:first)
+          @coords.first
         elsif @coords.respond_to?(:lat)
           @coords.lat
         else
@@ -197,8 +197,8 @@ def lat
       end
 
       def lng
-        if @coords.respond_to?(:[])
-          @coords[1]
+        if @coords.respond_to?(:last)
+          @coords.last
         elsif @coords.respond_to?(:lng)
           @coords.lng
         elsif @coords.respond_to?(:lon)

sunspot_rails/spec/mock_app/app/models/location.rb

@@ -0,0 +1,2 @@
+class Location < ActiveRecord::Base
+end

sunspot_rails/spec/mock_app/app/models/post.rb

@@ -1,5 +1,8 @@
 class Post < ActiveRecord::Base
+  belongs_to :location
+
   searchable :auto_index => false, :auto_remove => false do
     string :title
+    coordinates :location
   end
 end

sunspot_rails/spec/model_spec.rb

@@ -154,6 +154,14 @@
       end.results.should == [@post]
     end
 
+    it 'should use an ActiveRecord object for coordinates' do
+      post = Post.new(:title => 'Test Post')
+      post.location = Location.create!(:lat => 40.0, :lng => -70.0)
+      post.save
+      post.index!
+      Post.search { near([40.0, -70.0], :distance => 1) }.results.should == [post]
+    end
+
   end
 
   describe 'search_ids()' do

sunspot_rails/spec/schema.rb

@@ -2,11 +2,17 @@
   create_table :posts, :force => true do |t|
     t.string :title
     t.string :type
+    t.integer :location_id
     t.text :body
     t.references :blog
     t.timestamps
   end
 
+  create_table :locations, :force => true do |t|
+    t.float :lat
+    t.float :lng
+  end
+
   create_table :blogs, :force => true do |t|
     t.string :name
     t.string :subdomain