Refactoring module jbuilder for supporting jbuilder's partials

Author: gazay

lib/gon/jbuilder.rb

@@ -1,17 +1,45 @@
-require 'jbuilder'
-
 module Gon
   module Jbuilder
     class << self
+
+      def parse_source(source, controller)
+        output = ::JbuilderTemplate.encode(controller) do |json|
+          eval source
+        end
+        JSON.parse(output)
+      end
+
       def parse_jbuilder(jbuilder_path, controller)
-        source = File.read(jbuilder_path)
         controller.instance_variables.each do |name|
           self.instance_variable_set(name, controller.instance_variable_get(name))
         end
-        output = ::JbuilderTemplate.encode(controller) do |json|
-          eval source
+        lines = find_partials(File.readlines(jbuilder_path))
+        source = lines.join('')
+
+        output = parse_source(source, controller)
+      end
+
+      def parse_partial(partial_line)
+        path = partial_line.match(/['"]([^'"]*)['"]/)[1]
+        options_hash = partial_line.match(/,(.*)/)[1]
+        if options_hash.present?
+          options = eval '{' + options_hash + '}'
+          options.each do |name, val|
+            self.instance_variable_set('@' + name.to_s, val)
+            eval "def #{name}; self.instance_variable_get('@' + '#{name.to_s}'); end"
+          end
         end
-        JSON.parse(output)
+        find_partials(File.readlines(path))
+      end
+
+      def find_partials(lines = [])
+        lines.map do |line|
+          if line =~ /partial!/
+            parse_partial(line)
+          else
+            line
+          end
+        end.flatten
       end
     end
   end

spec/gon/gon_spec.rb

@@ -2,7 +2,8 @@
 require 'gon'
 
 describe Gon, '#all_variables' do 
-  before(:each) do 
+
+  before(:each) do
     Gon.request_env = {}
   end
 
@@ -49,26 +50,45 @@
     Gon.objects.length.should == 2
   end
 
-  it 'render json from jbuilder template' do
-    Gon.clear
-    controller = ActionController::Base.new
-    objects = [1,2]
-    controller.instance_variable_set('@objects', objects)
-    Gon.jbuilder 'spec/test_data/sample.json.jbuilder', :controller => controller
-    Gon.objects.length.should == 2
-  end
+  if RUBY_VERSION =~ /1.9/
+    require 'jbuilder'
+    require 'gon/jbuilder'
 
-  it 'render json from jbuilder template with a partial' do
-    Gon.clear
-    controller = ActionController::Base.new
-    controller.view_paths << 'spec/test_data'
-    objects = [1,2]
-    controller.instance_variable_set('@objects', objects)
-    Gon.jbuilder 'spec/test_data/sample_with_partial.json.jbuilder', :controller => controller
-    Gon.objects.length.should == 2
+    it 'render json from jbuilder template' do
+      Gon.clear
+      controller = ActionController::Base.new
+      objects = [1,2]
+      controller.instance_variable_set('@objects', objects)
+      Gon.jbuilder 'spec/test_data/sample.json.jbuilder', :controller => controller
+      Gon.objects.length.should == 2
+    end
+
+    it 'render json from jbuilder template with a partial' do
+      Gon.clear
+      controller = ActionController::Base.new
+      controller.view_paths << 'spec/test_data'
+      objects = [1,2]
+      controller.instance_variable_set('@objects', objects)
+      Gon.jbuilder 'spec/test_data/sample_with_partial.json.jbuilder', :controller => controller
+      Gon.objects.length.should == 2
+    end
+
+    it 'should throw error if you use gon.jbuilder with ruby < 1.9+' do
+      RUBY_VERSION = '1.8.7'
+
+      expect { Gon.jbuilder 'some_path' }.to raise_error(NoMethodError, /1.9/)
+    end
+
+    it 'should raise error if you use gon.jbuilder without requairing jbuilder gem' do
+      RUBY_VERSION = '1.9.2'
+      Gon.send(:remove_const, :Jbuilder)
+
+      expect { Gon.jbuilder 'some_path' }.to raise_error(NoMethodError, /Gemfile/)
+    end
   end
 
   def request
     @request ||= double 'request', :env => {}
   end
+
 end

spec/test_data/sample_with_partial.json.jbuilder

@@ -1 +1 @@
-json.partial! 'sample_partial', :objects => @objects
+json.partial! 'spec/test_data/_sample_partial.json.jbuilder', :objects => @objects