Merge pull request #864 from mojombo/prioritize_plugins

Prioritize plugins & DRY subclass instantiation

lib/jekyll/site.rb

@@ -88,17 +88,8 @@ module Jekyll
         end
       end
 
-      self.converters = Jekyll::Converter.subclasses.select do |c|
-        !self.safe || c.safe
-      end.map do |c|
-        c.new(self.config)
-      end
-
-      self.generators = Jekyll::Generator.subclasses.select do |c|
-        !self.safe || c.safe
-      end.map do |c|
-        c.new(self.config)
-      end
+      self.converters = instantiate_subclasses(Jekyll::Converter)
+      self.generators = instantiate_subclasses(Jekyll::Generator)
     end
 
     # Internal: Setup the plugin search path
@@ -388,6 +379,21 @@ module Jekyll
       end
     end
 
+    # Create array of instances of the subclasses of the class or module
+    #   passed in as argument.
+    #
+    # klass - class or module containing the subclasses which should be
+    #         instantiated
+    #
+    # Returns array of instances of subclasses of parameter
+    def instantiate_subclasses(klass)
+      klass.subclasses.select do |c|
+        !self.safe || c.safe
+      end.sort.map do |c|
+        c.new(self.config)
+      end
+    end
+
     # Read the entries from a particular directory for processing
     #
     # dir - The String relative path of the directory to read

test/source/_plugins/dummy.rb

@@ -0,0 +1,8 @@
+module Jekyll
+  class Dummy < Generator
+    priority :high
+
+    def generate(site)
+    end
+  end
+end

test/test_site.rb

@@ -139,6 +139,11 @@ class TestSite < Test::Unit::TestCase
       assert_equal mtime3, mtime4 # no modifications, so must be the same
     end
 
+    should "setup plugins in priority order" do
+      assert_equal @site.converters.sort_by(&:class).map{|c|c.class.priority}, @site.converters.map{|c|c.class.priority}
+      assert_equal @site.generators.sort_by(&:class).map{|g|g.class.priority}, @site.generators.map{|g|g.class.priority}
+    end
+
     should "read layouts" do
       @site.read_layouts
       assert_equal ["default", "simple"].sort, @site.layouts.keys.sort