allow setting individual values in rails config, resolves #111

CHANGELOG.markdown

@@ -6,6 +6,7 @@
 * Don't use `-strip` option for optipng when the bin version is less than 0.7 [#106](https://github.com/toy/image_optim/issues/106) [@toy](https://github.com/toy)
 * Use quality `0..100` by default in lossy mode of pngquant worker [#77](https://github.com/toy/image_optim/issues/77) [@toy](https://github.com/toy)
 * Add `:disable_plugins` and `:enable_plugins` options to `svgo` worker [#110](https://github.com/toy/image_optim/pull/110) [@tomhughes](https://github.com/tomhughes)
+* Allow setting config in rails like `config.assets.image_optim.name = value` [#111](https://github.com/toy/image_optim/pull/111) [@toy](https://github.com/toy)
 
 ## v0.21.0 (2015-05-30)
 

lib/image_optim/railtie.rb

@@ -3,6 +3,8 @@
 class ImageOptim
   # Adds image_optim as preprocessor for gif, jpeg, png and svg images
   class Railtie < Rails::Railtie
+    config.assets.image_optim = ActiveSupport::OrderedOptions.new
+
     initializer 'image_optim.initializer' do |app|
       register_preprocessor(app) if register_preprocessor?(app)
     end

spec/image_optim/railtie_spec.rb

@@ -23,13 +23,21 @@ def self.name
         assets.paths = %w[spec/images]
 
         assets.delete(:compress)
-        assets.delete(:image_optim)
       end
 
       yield config if block_given?
     end.initialize!
   end
 
+  around do |example|
+    options = Marshal.dump(ImageOptim::Railtie.config.assets.image_optim)
+    begin
+      example.run
+    ensure
+      ImageOptim::Railtie.config.assets.image_optim = Marshal.load(options)
+    end
+  end
+
   after do
     Rails.application = nil
   end
@@ -88,6 +96,14 @@ def self.name
           config.assets.image_optim = hash
         end
       end
+
+      it 'is possible to assign individual values' do
+        hash = {:config_paths => 'config/image_optim.yml'}
+        expect(ImageOptim).to receive(:new).with(hash).and_call_original
+        init_rails_app do |config|
+          config.assets.image_optim.config_paths = 'config/image_optim.yml'
+        end
+      end
     end
   end