display single files from gist

jekyll.gemspec

@@ -30,7 +30,7 @@ Gem::Specification.new do |s|
   s.add_runtime_dependency('kramdown', "~> 0.14")
   s.add_runtime_dependency('pygments.rb', "~> 0.3.2")
   s.add_runtime_dependency('commander', "~> 4.1.3")
-  s.add_runtime_dependency('safe_yaml', "~> 0.7")
+  s.add_runtime_dependency('safe_yaml', "~> 0.7.0")
 
   s.add_development_dependency('rake', "~> 10.0.3")
   s.add_development_dependency('rdoc', "~> 3.11")

lib/jekyll/tags/gist.rb

@@ -2,16 +2,27 @@
 #
 # Example:
 #    {% gist 1234567 %}
+#    {% gist 1234567 file.rb %}
 
 module Jekyll
   class GistTag < Liquid::Tag
-    def initialize(tag_name, gist, tokens)
+    def render(context)
-      super
+      if tag_contents = @markup.match(/(\d+) (.*)/)
-      @gist = gist.strip
+        gist_id, filename = tag_contents[1].strip, tag_contents[2].strip
+        gist_script_tag(gist_id, filename)
+      else
+        "Error parsing gist id"
+      end
     end
 
-    def render(context)
+    private
-      "<script src=\"https://gist.github.com/#{@gist}.js\"> </script>"
+
+    def gist_script_tag(gist_id, filename=nil)
+      if filename.empty?
+        "<script src=\"https://gist.github.com/#{gist_id}.js\">\s</script>"
+      else
+        "<script src=\"https://gist.github.com/#{gist_id}.js?file=#{filename}\">\s</script>"
+      end
     end
   end
 end

test/test_tags.rb

@@ -170,7 +170,7 @@ CONTENT
         assert_match %r{<em>FINISH HIM</em>}, @result
       end
     end
-    
+
     context "using Redcarpet" do
       setup do
         create_post(@content, 'markdown' => 'redcarpet')
@@ -203,22 +203,78 @@ CONTENT
       assert_match %r{/2008/11/21/complex/}, @result
     end
   end
-  
+
-  context "simple gist inclusion" do
+  context "gist tag" do
-    setup do
+    context "simple" do
-      @gist = 358471
+      setup do
-      content = <<CONTENT
+        @gist = 358471
+        content = <<CONTENT
 ---
 title: My Cool Gist
 ---
 
 {% gist #{@gist} %}
 CONTENT
-      create_post(content, {'permalink' => 'pretty', 'source' => source_dir, 'destination' => dest_dir, 'read_posts' => true})
+        create_post(content, {'permalink' => 'pretty', 'source' => source_dir, 'destination' => dest_dir, 'read_posts' => true})
+      end
+
+      should "write script tag" do
+        assert_match "<script src='https://gist.github.com/#{@gist}.js'>\s</script>", @result
+      end
     end
-    
+
-    should "write script tag" do
+    context "with specific file" do
-      assert_match %r{<script src='https://gist.github.com/#{@gist}.js'>\s</script>}, @result
+      setup do
+        @gist = 358471
+        @filename = 'somefile.rb'
+        content = <<CONTENT
+---
+title: My Cool Gist
+---
+
+{% gist #{@gist} #{@filename} %}
+CONTENT
+        create_post(content, {'permalink' => 'pretty', 'source' => source_dir, 'destination' => dest_dir, 'read_posts' => true})
+      end
+
+      should "write script tag with specific file in gist" do
+        assert_match "<script src='https://gist.github.com/#{@gist}.js?file=#{@filename}'>\s</script>", @result
+      end
+    end
+
+    context "with blank gist id" do
+      setup do
+        content = <<CONTENT
+---
+title: My Cool Gist
+---
+
+{% gist %}
+CONTENT
+        create_post(content, {'permalink' => 'pretty', 'source' => source_dir, 'destination' => dest_dir, 'read_posts' => true})
+      end
+
+      should "output error message" do
+        assert_match "Error parsing gist id", @result
+      end
+    end
+
+    context "with invalid gist id" do
+      setup do
+        invalid_gist = 'invalid'
+        content = <<CONTENT
+---
+title: My Cool Gist
+---
+
+{% gist #{invalid_gist} %}
+CONTENT
+        create_post(content, {'permalink' => 'pretty', 'source' => source_dir, 'destination' => dest_dir, 'read_posts' => true})
+      end
+
+      should "output error message" do
+        assert_match "Error parsing gist id", @result
+      end
     end
   end
 end