Added that gems can now be plugins if they include rails/init.rb (closes #11444) [jbarnette]

git-svn-id: http://svn-commit.rubyonrails.org/rails/trunk@9101 5ecf4fe2-1ee6-0310-87b1-e25e094e27de

2 files changed, 40 insertions, 1 deletions

diff --git a/railties/lib/rails/plugin.rb b/railties/lib/rails/plugin.rb
index 03fa309ca3..b45ec7de0e 100644
--- a/railties/lib/rails/plugin.rb
+++ b/railties/lib/rails/plugin.rb
@@ -97,4 +97,24 @@ module Rails
          end
       end               
   end
+
+  # This Plugin subclass represents a Gem plugin. It behaves exactly like a
+  # "traditional" Rails plugin, but doesn't expose any additional load paths,
+  # since RubyGems has already taken care of things.
+  class GemPlugin < Plugin
+
+    # Initialize this plugin from a Gem::Specification.
+    def initialize(spec)
+      super(File.join(spec.full_gem_path, "rails"))
+      @name = spec.name
+    end
+
+    def valid?
+      true
+    end
+
+    def load_paths
+      []
+    end
+  end
 end
\ No newline at end of file
diff --git a/railties/lib/rails/plugin/locator.rb b/railties/lib/rails/plugin/locator.rb
index b27e904b12..0b7923cfb6 100644
--- a/railties/lib/rails/plugin/locator.rb
+++ b/railties/lib/rails/plugin/locator.rb
@@ -72,7 +72,26 @@ module Rails
             plugins
           end
         end
-        
+    end
+
+    # The GemLocator scans all the loaded RubyGems, looking for gems with
+    # a <tt>rails/init.rb</tt> file.
+    class GemLocator < Locator
+      def plugins
+        specs = Gem.loaded_specs.values.select do |spec|
+          spec.loaded_from && # prune stubs
+            File.exist?(File.join(spec.full_gem_path, "rails", "init.rb"))
+        end
+
+        require "rubygems/dependency_list"
+
+        deps = Gem::DependencyList.new
+        deps.add(*specs)
+
+        deps.dependency_order.collect do |spec|
+          Rails::GemPlugin.new(spec)
+        end
+      end
     end
   end
 end
\ No newline at end of file