vendor/rails/actionpack/lib/action_view/renderable.rb

   1 # encoding: utf-8
   2
   3 module ActionView
   4   # NOTE: The template that this mixin is being included into is frozen
   5   # so you cannot set or modify any instance variables
   6   module Renderable #:nodoc:
   7     extend ActiveSupport::Memoizable
   8
   9     def filename
  10       'compiled-template'
  11     end
  12
  13     def handler
  14       Template.handler_class_for_extension(extension)
  15     end
  16     memoize :handler
  17
  18     def compiled_source
  19       handler.call(self)
  20     end
  21
  22     def method_name_without_locals
  23       ['_run', extension, method_segment].compact.join('_')
  24     end
  25     memoize :method_name_without_locals
  26
  27     def render(view, local_assigns = {})
  28       compile(local_assigns)
  29
  30       view.with_template self do
  31         view.send(:_evaluate_assigns_and_ivars)
  32         view.send(:_set_controller_content_type, mime_type) if respond_to?(:mime_type)
  33
  34         view.send(method_name(local_assigns), local_assigns) do |*names|
  35           ivar = :@_proc_for_layout
  36           if !view.instance_variable_defined?(:"@content_for_#{names.first}") && view.instance_variable_defined?(ivar) && (proc = view.instance_variable_get(ivar))
  37             view.capture(*names, &proc)
  38           elsif view.instance_variable_defined?(ivar = :"@content_for_#{names.first || :layout}")
  39             view.instance_variable_get(ivar)
  40           end
  41         end
  42       end
  43     end
  44
  45     def method_name(local_assigns)
  46       if local_assigns && local_assigns.any?
  47         method_name = method_name_without_locals.dup
  48         method_name << "_locals_#{local_assigns.keys.map { |k| k.to_s }.sort.join('_')}"
  49       else
  50         method_name = method_name_without_locals
  51       end
  52       method_name.to_sym
  53     end
  54
  55     private
  56       # Compile and evaluate the template's code (if necessary)
  57       def compile(local_assigns)
  58         render_symbol = method_name(local_assigns)
  59
  60         if !Base::CompiledTemplates.method_defined?(render_symbol) || recompile?
  61           compile!(render_symbol, local_assigns)
  62         end
  63       end
  64
  65       def compile!(render_symbol, local_assigns)
  66         locals_code = local_assigns.keys.map { |key| "#{key} = local_assigns[:#{key}];" }.join
  67
  68         source = <<-end_src
  69           def #{render_symbol}(local_assigns)
  70             old_output_buffer = output_buffer;#{locals_code};#{compiled_source}
  71           ensure
  72             self.output_buffer = old_output_buffer
  73           end
  74         end_src
  75
  76         begin
  77           ActionView::Base::CompiledTemplates.module_eval(source, filename, 0)
  78         rescue Errno::ENOENT => e
  79           raise e # Missing template file, re-raise for Base to rescue
  80         rescue Exception => e # errors from template code
  81           if logger = defined?(ActionController) && Base.logger
  82             logger.debug "ERROR: compiling #{render_symbol} RAISED #{e}"
  83             logger.debug "Function body: #{source}"
  84             logger.debug "Backtrace: #{e.backtrace.join("\n")}"
  85           end
  86
  87           raise ActionView::TemplateError.new(self, {}, e)
  88         end
  89       end
  90
  91       def recompile?
  92         false
  93       end
  94   end
  95 end