add display_path option for sites not hosted at domain root

README.md

@@ -263,6 +263,7 @@ asset_pipeline:
   bundle: true            # Default = true
   compress: true          # Default = true
   output_path: assets     # Default = assets
+  display_path: nil       # Default = nil
   gzip: false             # Default = false
 ```
 
@@ -271,6 +272,7 @@ asset_pipeline:
 > - The "bundle" setting controls whether Jekyll Asset Pipeline bundles the assets defined in each manifest.  If "bundle" is set to false, each asset will be saved individually and individual html tags pointing to each unbundled asset will be produced when you compile your site.  It is useful to set this to false while you are debugging your site.
 > - The "compress" setting tells Jekyll Asset Pipeline whether or not to compress the bundled assets.  It is useful to set this setting to "false" while you are debugging your site.
 > - The "output\_path" setting defines where generated bundles should be saved within the "\_site" folder of your project.
+> - The "display\_path" setting overrides the path to assets in generated html tags.  This is useful if you are hosting your site at a path other than the root of your domain (e.g. "http://example.com/blog/").
 > - The "gzip" setting controls whether Jekyll Asset Pipeline saves gzipped versions of your assets alongside un-gzipped versions.
 
 ## Octopress

lib/jekyll_asset_pipeline.rb

@@ -39,6 +39,7 @@ module JekyllAssetPipeline
   # Strings used for keys to play nice when merging with _config.yml
   DEFAULTS = {
     'output_path'   => 'assets',    # Destination for bundle file (within the '_site' directory)
+    'display_path'  => nil,         # Optional.  Override path to assets for output HTML refs
     'bundle'        => true,        # true = Bundle assets, false = Leave assets unbundled
     'compress'      => true,        # true = Minify assets, false = Leave assets unminified
     'gzip'          => false        # true = Create gzip versions, false = Do not create gzip versions

lib/jekyll_asset_pipeline/pipeline.rb

@@ -202,14 +202,15 @@ def save
 
     # Generate html markup pointing to assets
     def markup
-      path = @options['output_path']
+      # Use display_path if defined, otherwise use output_path in url
+      display_path = @options['display_path'] || @options['output_path']
 
       @html = @assets.map do |asset|
         klass = JekyllAssetPipeline::Template.subclasses.select do |t|
           t.filetype == File.extname(asset.filename).downcase
         end.sort! { |x, y| x.priority <=> y.priority }.last
 
-        html = klass.new(path, asset.filename).html unless klass.nil?
+        html = klass.new(display_path, asset.filename).html unless klass.nil?
 
         html
       end.join

lib/jekyll_asset_pipeline/template.rb

@@ -20,8 +20,8 @@ def self.priority
     # HTML output to return
     #
     # Available instance variables:
-    # @path       Path to bundle file
-    # @filename   Name of bundle file
+    # @filename       Name of bundle file
+    # @path           Path to bundle file
     #
     # Returns string
     def html

spec/integration_spec.rb

@@ -4,7 +4,7 @@
   # Sensible defaults
   let(:manifest) { "- /_assets/foo.css\n- /_assets/bar.css" }
   let(:prefix) { 'global' }
-  let(:config) { { 'output_path' => 'foobar' } }
+  let(:config) { {} }
   let(:tag_name) { 'css_asset_tag' }
   let(:extension) { '.css' }
 
@@ -15,6 +15,7 @@
 
   it "saves assets to output path" do
     $stdout.stub(:puts, nil) do
+      config['output_path'] = 'foobar_assets'
       pipeline, cached = Pipeline.run(manifest, prefix, source_path, temp_path,
                                       tag_name, extension, config)
       pipeline.assets.each do |asset|
@@ -29,7 +30,7 @@
   it "outputs processing and saved file status messages" do
     hash = Pipeline.hash(source_path, manifest, config)
     filename = "#{prefix}-#{hash}#{extension}"
-    path = File.join(temp_path, config['output_path'])
+    path = File.join(temp_path, DEFAULTS['output_path'])
 
     expected = "Asset Pipeline: Processing '#{tag_name}' manifest '#{prefix}'\n" +
                "Asset Pipeline: Saved '#{filename}' to '#{path}'\n"
@@ -121,6 +122,15 @@ def html
         pipeline.html.must_match(/script/i)
       end
     end
+
+    it "links to display_path if option is set" do
+      $stdout.stub(:puts, nil) do
+        config['display_path'] = 'foo/bar/baz'
+        pipeline, cached = Pipeline.run(manifest, prefix, source_path, temp_path,
+                                        tag_name, '.js', config)
+        pipeline.html.must_match(/foo\/bar\/baz/)
+      end
+    end
   end
 
   context "bundle => true" do