Add draft and post front matter support.

able to add draft and post front matter in _config.yml in Jekyll
directory.
adopted from toshimaru's PR
(jekyll#41)

lib/jekyll-compose/file_info.rb

@@ -9,11 +9,11 @@ def file_name
     "#{name}.#{params.type}"
   end
 
-  def content
+  def content(addtional_front_matter = {})
     front_matter = YAML.dump({
       'layout' => params.layout,
       'title' => params.title,
-    })
+    }.merge(addtional_front_matter))
 
     front_matter + "---\n"
   end

lib/jekyll/commands/draft.rb

@@ -40,6 +40,11 @@ def resource_type
         def path
           "_drafts/#{file_name}"
         end
+
+        def content
+          post_front_matter = Jekyll.configuration["post_front_matter"]
+          post_front_matter ? super(post_front_matter) : super
+        end
       end
     end
   end

lib/jekyll/commands/post.rb

@@ -55,6 +55,11 @@ def file_name
         def _date_stamp
           @params.date.strftime '%Y-%m-%d'
         end
+
+        def content
+          post_front_matter = Jekyll.configuration["post_front_matter"]
+          post_front_matter ? super(post_front_matter) : super
+        end
       end
     end
   end

spec/draft_spec.rb

@@ -50,6 +50,8 @@
   it 'creates a new draft with the specified layout' do
     capture_stdout { described_class.process(args, 'layout' => 'other-layout') }
     expect(File.read(path)).to match(/layout: other-layout/)
+    expect(File.read(path)).to match(/description: my description/)
+    expect(File.read(path)).to mathc(/category: /)
   end
 
   context 'when the draft already exists' do

spec/fixtures/_config.yml

@@ -0,0 +1,3 @@
+post_front_matter:
+  description: my description
+  category:

spec/post_spec.rb

@@ -5,6 +5,7 @@
   let(:datestamp) { Time.now.strftime('%Y-%m-%d') }
   let(:filename) { "#{datestamp}-a-test-post.md" }
   let(:path) { posts_dir.join(filename) }
+  let(:jekyll_config) {YAML.load_file('../fixtures/_config.yml')}
 
   before(:all) do
     FileUtils.mkdir_p source_dir unless File.directory? source_dir
@@ -44,6 +45,13 @@
     expect(File.read(path)).to match(/layout: other-layout/)
   end
 
+  it 'creates a new page with the specified config' do
+    expect(Jekyll).to receive(:configuration).and_return(jekyll_config)
+    capture_stdout { described_class.process(args) }
+    expect(File.read(path)).to match(/description: my description/)
+    expect(File.read(path)).to match(/category: /)
+  end
+
   it 'should write a helpful message when successful' do
     output = capture_stdout { described_class.process(args) }
     expect(output).to eql("New post created at _posts/#{filename}.\n")