Merged updates from trunk into stable branch

[feedcatcher.git] / vendor / rails / actionpack / lib / action_view / reloadable_template.rb

diff --git a/vendor/rails/actionpack/lib/action_view/reloadable_template.rb b/vendor/rails/actionpack/lib/action_view/reloadable_template.rb
new file mode 100644 (file)
index 0000000..5ef833d
--- /dev/null
+++ b/vendor/rails/actionpack/lib/action_view/reloadable_template.rb
@@ -0,0 +1,117 @@
+module ActionView #:nodoc:
+  class ReloadableTemplate < Template
+
+    class TemplateDeleted < ActionView::ActionViewError
+    end
+
+    class ReloadablePath < Template::Path
+
+      def initialize(path)
+        super
+        @paths = {}
+        new_request!
+      end
+
+      def new_request!
+        @disk_cache = {}
+      end
+      alias_method :load!, :new_request!
+
+      def [](path)
+        if found_template = @paths[path]
+          begin
+            found_template.reset_cache_if_stale!
+          rescue TemplateDeleted
+            unregister_template(found_template)
+            self[path]
+          end
+        else
+          load_all_templates_from_dir(templates_dir_from_path(path))
+          # don't ever hand out a template without running a stale check
+          (new_template = @paths[path]) && new_template.reset_cache_if_stale!
+        end
+      end
+
+      private
+        def register_template_from_file(template_full_file_path)
+          if !@paths[relative_path = relative_path_for_template_file(template_full_file_path)] && File.file?(template_full_file_path)
+            register_template(ReloadableTemplate.new(relative_path, self))
+          end
+        end
+
+        def register_template(template)
+          template.accessible_paths.each do |path|
+            @paths[path] = template
+          end
+        end
+
+        # remove (probably deleted) template from cache
+        def unregister_template(template)
+          template.accessible_paths.each do |template_path|
+            @paths.delete(template_path) if @paths[template_path] == template
+          end
+          # fill in any newly created gaps
+          @paths.values.uniq.each do |template|
+            template.accessible_paths.each {|path| @paths[path] ||= template}
+          end
+        end
+
+        # load all templates from the directory of the requested template
+        def load_all_templates_from_dir(dir)
+          # hit disk only once per template-dir/request
+          @disk_cache[dir] ||= template_files_from_dir(dir).each {|template_file| register_template_from_file(template_file)}
+        end
+
+        def templates_dir_from_path(path)
+          dirname = File.dirname(path)
+          File.join(@path, dirname == '.' ? '' : dirname)
+        end
+
+        # get all the template filenames from the dir
+        def template_files_from_dir(dir)
+          Dir.glob(File.join(dir, '*'))
+        end
+    end
+
+    module Unfreezable
+      def freeze; self; end
+    end
+
+    def initialize(*args)
+      super
+      
+      # we don't ever want to get frozen
+      extend Unfreezable
+    end
+
+    def mtime
+      File.mtime(filename)
+    end
+
+    attr_accessor :previously_last_modified
+
+    def stale?
+      previously_last_modified.nil? || previously_last_modified < mtime
+    rescue Errno::ENOENT => e
+      undef_my_compiled_methods!
+      raise TemplateDeleted
+    end
+
+    def reset_cache_if_stale!
+      if stale?
+        flush_cache 'source', 'compiled_source'
+        undef_my_compiled_methods!
+        @previously_last_modified = mtime
+      end
+      self
+    end
+
+    # remove any compiled methods that look like they might belong to me
+    def undef_my_compiled_methods!
+      ActionView::Base::CompiledTemplates.public_instance_methods.grep(/#{Regexp.escape(method_name_without_locals)}(?:_locals_)?/).each do |m|
+        ActionView::Base::CompiledTemplates.send(:remove_method, m)
+      end
+    end
+
+  end
+end