1 files changed, 82 insertions, 0 deletions
diff --git a/actionpack/lib/action_controller/abstract/layouts.rb b/actionpack/lib/action_controller/abstract/layouts.rb
new file mode 100644
index 0000000000..478b301a26
--- /dev/null
+++ b/actionpack/lib/action_controller/abstract/layouts.rb
@@ -0,0 +1,82 @@
+module AbstractController
+  module Layouts
+    
+    depends_on Renderer
+        
+    module ClassMethods
+      def layout(layout)
+        unless [String, Symbol, FalseClass, NilClass].include?(layout.class)
+          raise ArgumentError, "Layouts must be specified as a String, Symbol, false, or nil"
+        end
+        
+        @_layout = layout || false # Converts nil to false
+        _write_layout_method
+      end
+      
+      def _implied_layout_name
+        name.underscore
+      end
+      
+      # Takes the specified layout and creates a _layout method to be called
+      # by _default_layout
+      # 
+      # If the specified layout is a:
+      # String:: return the string
+      # Symbol:: call the method specified by the symbol
+      # false::  return nil
+      # none::   If a layout is found in the view paths with the controller's
+      #          name, return that string. Otherwise, use the superclass'
+      #          layout (which might also be implied)
+      def _write_layout_method
+        case @_layout
+        when String
+          self.class_eval %{def _layout() #{@_layout.inspect} end}
+        when Symbol
+          self.class_eval %{def _layout() #{@_layout} end}
+        when false
+          self.class_eval %{def _layout() end}
+        else
+          self.class_eval %{
+            def _layout
+              if view_paths.find_by_parts?("#{_implied_layout_name}", formats, "layouts")
+                "#{_implied_layout_name}"
+              else
+                super
+              end
+            end
+          }
+        end
+      end
+    end
+    
+    def _render_template(template, options)
+      _action_view._render_template_with_layout(template, options[:_layout])
+    end
+        
+  private
+  
+    def _layout() end # This will be overwritten
+    
+    def _layout_for_name(name)
+      unless [String, FalseClass, NilClass].include?(name.class)
+        raise ArgumentError, "String, false, or nil expected; you passed #{name.inspect}"
+      end
+      
+      name && view_paths.find_by_parts(name, formats, "layouts")
+    end
+    
+    def _default_layout(require_layout = false)
+      if require_layout && !_layout
+        raise ArgumentError, 
+          "There was no default layout for #{self.class} in #{view_paths.inspect}"
+      end
+        
+      begin
+        layout = _layout_for_name(_layout)
+      rescue NameError => e
+        raise NoMethodError, 
+          "You specified #{@_layout.inspect} as the layout, but no such method was found"
+      end
+    end
+  end
+end
+\ No newline at end of file