take underscored image names into account while simplifying options p…

…arsing

* takes advantage of `rpartition` to more efficiently (and clearly) split the options
* swaps where we `to_s` the hash keys in favor of symbolizing in fewer places

lib/spritely/options.rb

@@ -1,10 +1,11 @@
 require 'active_support/core_ext/hash/deep_merge'
 require 'active_support/core_ext/hash/except'
+require 'active_support/core_ext/hash/keys'
 require 'active_support/core_ext/hash/slice'
 
 module Spritely
   class Options < Struct.new(:hash)
-    GLOBAL_OPTIONS = [:spacing, :position]
+    GLOBAL_OPTIONS = ['spacing', 'position']
 
     def cache_key
       stripped_hash.to_s
@@ -15,28 +16,26 @@ def inspect
     end
 
     def [](key)
-      options[key] || global_options
+      options[key.gsub('-', '_')] || global_options
     end
 
     private
 
     def options
       @options ||= stripped_hash.except(*GLOBAL_OPTIONS).inject({}) do |h, (key, value)|
-        split_key = key.to_s.split('_')
-        option = {split_key.pop.to_sym => value}
-        image = split_key.join('-')
+        image, _, option = key.rpartition('_')
         h[image] ||= global_options.dup
-        h.deep_merge!(image => option)
+        h.deep_merge!(image => {option.to_sym => value})
       end
     end
 
     def global_options
-      @global_options ||= stripped_hash.slice(*GLOBAL_OPTIONS)
+      @global_options ||= stripped_hash.slice(*GLOBAL_OPTIONS).symbolize_keys!
     end
 
     def stripped_hash
       @stripped_hash ||= hash.inject({}) do |h, (key, sass_object)|
-        h.merge!(key.to_sym => sass_object.value)
+        h.merge!(key => sass_object.value)
       end
     end
   end

spec/spritely/options_spec.rb

@@ -14,16 +14,16 @@
 
   subject(:options) { Spritely::Options.new(hash) }
 
-  its(:inspect) { should eq("#<Spritely::Options global_options=#{{spacing: 901, position: 'left'}} options=#{{'some-new-image' => {spacing: 789, position: 'right', x: 123, y: 456}, 'another-image' => {spacing: 901, position: 'left', repeat: true}, 'yet-another-image' => {spacing: 901, position: 'left', repeat: false}}}>") }
-  its(:cache_key) { should eq({some_new_image_spacing: 789, some_new_image_x: 123, some_new_image_y: 456, some_new_image_position: 'right', another_image_repeat: true, yet_another_image_repeat: false, spacing: 901, position: 'left'}.to_s) }
+  its(:inspect) { should eq("#<Spritely::Options global_options=#{{spacing: 901, position: 'left'}} options=#{{'some_new_image' => {spacing: 789, position: 'right', x: 123, y: 456}, 'another_image' => {spacing: 901, position: 'left', repeat: true}, 'yet_another_image' => {spacing: 901, position: 'left', repeat: false}}}>") }
+  its(:cache_key) { should eq({"some_new_image_spacing" => 789, "some_new_image_x" => 123, "some_new_image_y" => 456, "some_new_image_position" => 'right', "another_image_repeat" => true, "yet_another_image_repeat" => false, "spacing" => 901, "position" => 'left'}.to_s) }
 
   its(['some-new-image']) { should eq({spacing: 789, position: 'right', x: 123, y: 456}) }
   its(['another-image']) { should eq({spacing: 901, repeat: true, position: 'left'}) }
   its(['yet-another-image']) { should eq({spacing: 901, repeat: false, position: 'left'}) }
 
   describe '#[]' do
     it 'should fall back to an empty hash' do
-      expect(options[:unknown]).to eq({spacing: 901, position: 'left'})
+      expect(options['unknown']).to eq({spacing: 901, position: 'left'})
     end
   end
 end