add recursion feature for validating nested attributes

add tests for nested attributes

lib/rails_param/param.rb

@@ -7,6 +7,13 @@ module RailsParam
             attr_accessor :param, :options
         end
 
+        class MockController
+            include RailsParam::Param
+            attr_accessor :params
+            # def params
+            # end
+        end
+
         def param!(name, type, options = {})
             name = name.to_s
 
@@ -17,8 +24,19 @@ module RailsParam
                 params[name] = (options[:default].call if options[:default].respond_to?(:call)) || options[:default] if params[name].nil? and options[:default]
                 params[name] = options[:transform].to_proc.call(params[name]) if params[name] and options[:transform]
                 validate!(params[name], options)
+                if block_given?
+                    controller = RailsParam::Param::MockController.new
+                    controller.params = params[name]
+                    # begin
+                        yield(controller)
+
+                        # exception.param, exception.options = name, options
+                        # raise InvalidParameterError exception
+                    # end
+                end
             rescue InvalidParameterError => exception
-        exception.param, exception.options = name, options
+                exception.param ||= name
+                exception.options ||= options
                 raise exception
             end
         end
@@ -58,7 +76,7 @@ module RailsParam
                 return (/(false|f|no|n|0)$/i === param.to_s ? false : (/(true|t|yes|y|1)$/i === param.to_s ? true : nil)) if type == TrueClass || type == FalseClass || type == :boolean
                 if type == BigDecimal
                     param = param.delete('$,').strip.to_f if param.is_a?(String)
-          return BigDecimal.new(param, (options[:precision] || DEFAULT_PRECISION)) if type == BigDecimal
+                    return BigDecimal.new(param, (options[:precision] || DEFAULT_PRECISION))
                 end
                 return nil
             rescue ArgumentError

spec/fixtures/controllers.rb

@@ -17,4 +17,18 @@ class FakeController < ActionController::Base
   def new
     render text: "new"
   end
+
+    def edit
+        param! :book, Hash, required: true do |b|
+            b.param! :title, String, required: true
+            b.param! :author, Hash do |a|
+                a.param! :first_name, String, required: true
+                a.param! :last_name, String, required: true
+                a.param! :age, Integer, required: true
+            end
+            b.param! :price, BigDecimal, required: true
+        end
+        render text: :book
+    end
+
 end

spec/fixtures/fake_rails_application.rb

@@ -15,6 +15,7 @@ module Rails
         get '/fake/new' => "fake#new"
         get '/fakes' => "fake#index"
         get '/fake/(:id)' => "fake#show"
+          get '/fake/edit' => "fake#edit"
       end
       @routes
     end

spec/rails_integration_spec.rb

@@ -10,6 +10,54 @@ describe FakeController, type: :controller do
     end
   end
 
+  describe "nested_hash" do
+      it "validates nested properties" do
+          params = {
+              'book' => {
+                  'title' => 'One Hundred Years of Solitude',
+                  'author' => {
+                      'first_name' => 'Garbriel Garcia',
+                      'last_name' => 'Marquez',
+                      'age' => '70'
+                  },
+                  'price' => '$1,000.00'
+              }}
+          get :edit, params
+          expect(controller.params[:book][:author][:age]).to eql 70
+          expect(controller.params[:book][:author][:age]).to be_kind_of Integer
+          expect(controller.params[:book][:price]).to eql 1000.0
+          expect(controller.params[:book][:price]).to be_instance_of BigDecimal
+      end
+
+      it "raises error when required nested attribute missing" do
+          params = {
+              'book' => {
+                  'title' => 'One Hundred Years of Solitude',
+                  'author' => {
+                      'last_name' => 'Marquez',
+                      'age' => '70'
+                  },
+                  'price' => '$1,000.00'
+              }}
+          expect { get :edit, params }.to raise_error { |error|
+              expect(error).to be_a(RailsParam::Param::InvalidParameterError)
+              expect(error.param).to eql("first_name")
+              expect(error.options).to eql({ :required => true })
+          }
+      end
+
+      it "passes when hash that's not required but has required attributes is missing" do
+          params = {
+              'book' => {
+                  'title' => 'One Hundred Years of Solitude',
+                  'price' => '$1,000.00'
+              }}
+          get :edit, params
+          expect(controller.params[:book][:price]).to eql 1000.0
+          expect(controller.params[:book][:price]).to be_instance_of BigDecimal
+      end
+  end
+
   describe "InvalidParameterError" do
     it "raises an exception with params attributes" do
       expect { get :index, sort: "foo" }.to raise_error { |error|