Froze rails gems

[depot.git] / vendor / rails / railties / lib / rails / plugin / loader.rb

diff --git a/vendor/rails/railties/lib/rails/plugin/loader.rb b/vendor/rails/railties/lib/rails/plugin/loader.rb
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+++ b/vendor/rails/railties/lib/rails/plugin/loader.rb
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+require "rails/plugin"
+
+module Rails
+  class Plugin
+    class Loader
+      attr_reader :initializer
+
+      # Creates a new Plugin::Loader instance, associated with the given
+      # Rails::Initializer. This default implementation automatically locates
+      # all plugins, and adds all plugin load paths, when it is created. The plugins
+      # are then fully loaded (init.rb is evaluated) when load_plugins is called.
+      #
+      # It is the loader's responsibility to ensure that only the plugins specified
+      # in the configuration are actually loaded, and that the order defined
+      # is respected.
+      def initialize(initializer)
+        @initializer = initializer
+      end
+      
+      # Returns the plugins to be loaded, in the order they should be loaded.
+      def plugins
+        @plugins ||= all_plugins.select { |plugin| should_load?(plugin) }.sort { |p1, p2| order_plugins(p1, p2) }
+      end
+
+      # Returns all the plugins that could be found by the current locators.
+      def all_plugins
+        @all_plugins ||= locate_plugins
+        @all_plugins
+      end
+    
+      def load_plugins
+        plugins.each do |plugin| 
+          plugin.load(initializer)
+          register_plugin_as_loaded(plugin)
+        end
+        ensure_all_registered_plugins_are_loaded!
+      end
+      
+      # Adds the load paths for every plugin into the $LOAD_PATH. Plugin load paths are
+      # added *after* the application's <tt>lib</tt> directory, to ensure that an application
+      # can always override code within a plugin.
+      #
+      # Plugin load paths are also added to Dependencies.load_paths, and Dependencies.load_once_paths.  
+      def add_plugin_load_paths
+        plugins.each do |plugin|
+          plugin.load_paths.each do |path|
+            $LOAD_PATH.insert(application_lib_index + 1, path)
+            ActiveSupport::Dependencies.load_paths      << path
+            unless Rails.configuration.reload_plugins?
+              ActiveSupport::Dependencies.load_once_paths << path
+            end
+          end
+        end
+        $LOAD_PATH.uniq!
+      end      
+      
+      protected
+      
+        # The locate_plugins method uses each class in config.plugin_locators to
+        # find the set of all plugins available to this Rails application.
+        def locate_plugins
+          configuration.plugin_locators.map { |locator|
+            locator.new(initializer).plugins
+          }.flatten
+          # TODO: sorting based on config.plugins
+        end
+
+        def register_plugin_as_loaded(plugin)
+          initializer.loaded_plugins << plugin
+        end
+
+        def configuration
+          initializer.configuration
+        end
+        
+        def should_load?(plugin)
+          # uses Plugin#name and Plugin#valid?
+          enabled?(plugin) && plugin.valid?
+        end
+
+        def order_plugins(plugin_a, plugin_b)
+          if !explicit_plugin_loading_order?
+            plugin_a <=> plugin_b
+          else
+            if !explicitly_enabled?(plugin_a) && !explicitly_enabled?(plugin_b)
+              plugin_a <=> plugin_b
+            else
+              effective_order_of(plugin_a) <=> effective_order_of(plugin_b)
+            end            
+          end
+        end
+        
+        def effective_order_of(plugin)
+          if explicitly_enabled?(plugin)
+            registered_plugin_names.index(plugin.name) 
+          else
+            registered_plugin_names.index('all')
+          end        
+        end
+
+        def application_lib_index
+          $LOAD_PATH.index(File.join(RAILS_ROOT, 'lib')) || 0
+        end      
+
+        def enabled?(plugin)
+          !explicit_plugin_loading_order? || registered?(plugin)
+        end
+
+        def explicit_plugin_loading_order?
+          !registered_plugin_names.nil?
+        end
+
+        def registered?(plugin)
+          explicit_plugin_loading_order? && registered_plugins_names_plugin?(plugin)
+        end
+
+        def explicitly_enabled?(plugin)
+          !explicit_plugin_loading_order? || explicitly_registered?(plugin)
+        end
+
+        def explicitly_registered?(plugin)
+          explicit_plugin_loading_order? && registered_plugin_names.include?(plugin.name)
+        end
+      
+        def registered_plugins_names_plugin?(plugin)
+          registered_plugin_names.include?(plugin.name) || registered_plugin_names.include?('all')
+        end
+        
+        # The plugins that have been explicitly listed with config.plugins. If this list is nil
+        # then it means the client does not care which plugins or in what order they are loaded, 
+        # so we load all in alphabetical order. If it is an empty array, we load no plugins, if it is
+        # non empty, we load the named plugins in the order specified.
+        def registered_plugin_names
+          configuration.plugins ? configuration.plugins.map(&:to_s) : nil
+        end
+        
+        def loaded?(plugin_name)
+          initializer.loaded_plugins.detect { |plugin| plugin.name == plugin_name.to_s }
+        end
+        
+        def ensure_all_registered_plugins_are_loaded!
+          if explicit_plugin_loading_order?
+            if configuration.plugins.detect {|plugin| plugin != :all && !loaded?(plugin) }
+              missing_plugins = configuration.plugins - (plugins + [:all])
+              raise LoadError, "Could not locate the following plugins: #{missing_plugins.to_sentence}"
+            end
+          end
+        end
+  
+    end
+  end
+end
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