make action_controller/layouts pick templates from the current instan…

…ce's view_paths instead of the class view_paths [rails#1974 state:resolved]

Signed-off-by: Joshua Peek <josh@joshpeek.com>

actionpack/lib/action_controller/layout.rb

@@ -172,23 +172,10 @@ def layout_conditions #:nodoc:
         @layout_conditions ||= read_inheritable_attribute(:layout_conditions)
       end
 
-      def default_layout(format) #:nodoc:
-        layout = read_inheritable_attribute(:layout) unless format == :js
-        return layout unless read_inheritable_attribute(:auto_layout)
-        find_layout(layout, format)
-      end
-
       def layout_list #:nodoc:
         Array(view_paths).sum([]) { |path| Dir["#{path.to_str}/layouts/**/*"] }
       end
 
-      def find_layout(layout, *formats) #:nodoc:
-        return layout if layout.respond_to?(:render)
-        view_paths.find_template(layout.to_s =~ /layouts\// ? layout : "layouts/#{layout}", *formats)
-      rescue ActionView::MissingTemplate
-        nil
-      end
-
       private
         def inherited_with_layout(child)
           inherited_without_layout(child)
@@ -212,35 +199,29 @@ def normalize_conditions(conditions)
     # object). If the layout was defined without a directory, layouts is assumed. So <tt>layout "weblog/standard"</tt> will return
     # weblog/standard, but <tt>layout "standard"</tt> will return layouts/standard.
     def active_layout(passed_layout = nil)
-      layout = passed_layout || self.class.default_layout(default_template_format)
+      layout = passed_layout || default_layout
+      return layout if layout.respond_to?(:render)
 
       active_layout = case layout
         when Symbol then __send__(layout)
         when Proc   then layout.call(self)
         else layout
       end
-
-      if active_layout
-        if layout = self.class.find_layout(active_layout, @template.template_format)
-          layout
-        else
-          raise ActionView::MissingTemplate.new(self.class.view_paths, active_layout)
-        end
-      end
+
+      find_layout(active_layout, @template.template_format) if active_layout
     end
 
     private
-      def candidate_for_layout?(options)
-        template = options[:template] || default_template(options[:action])
-        if options.values_at(:text, :xml, :json, :file, :inline, :partial, :nothing, :update).compact.empty?
-          begin
-            !self.view_paths.find_template(template, default_template_format).exempt_from_layout?
-          rescue ActionView::MissingTemplate
-            true
-          end
-        end
+      def default_layout #:nodoc:
+        layout = self.class.read_inheritable_attribute(:layout) unless default_template_format == :js
+        return layout unless self.class.read_inheritable_attribute(:auto_layout)
+        find_layout(layout, default_template_format)
       rescue ActionView::MissingTemplate
-        false
+        nil
+      end
+
+      def find_layout(layout, *formats) #:nodoc:
+        view_paths.find_template(layout.to_s =~ /layouts\// ? layout : "layouts/#{layout}", *formats)
       end
 
       def pick_layout(options)
@@ -273,6 +254,19 @@ def action_has_layout?
         end
       end
 
+      def candidate_for_layout?(options)
+        template = options[:template] || default_template(options[:action])
+        if options.values_at(:text, :xml, :json, :file, :inline, :partial, :nothing, :update).compact.empty?
+          begin
+            !self.view_paths.find_template(template, default_template_format).exempt_from_layout?
+          rescue ActionView::MissingTemplate
+            true
+          end
+        end
+      rescue ActionView::MissingTemplate
+        false
+      end
+
       def default_template_format
         response.template.template_format
       end

actionpack/test/controller/layout_test.rb

@@ -83,6 +83,13 @@ class HasOwnLayoutController < LayoutTest
   layout 'item'
 end
 
+class PrependsViewPathController < LayoutTest
+  def hello
+    prepend_view_path File.dirname(__FILE__) + '/../fixtures/layout_tests/alt/'
+    render :layout => 'alt'
+  end
+end
+
 class SetsLayoutInRenderController < LayoutTest
   def hello
     render :layout => 'third_party_template_library'
@@ -130,6 +137,12 @@ def test_exempt_from_layout_honored_by_render_template
   ensure
     ActionController::Base.exempt_from_layout.delete(/\.rhtml$/)
   end
+
+  def test_layout_is_picked_from_the_controller_instances_view_path
+    @controller = PrependsViewPathController.new
+    get :hello
+    assert_equal 'layouts/alt', @response.layout
+  end
 end
 
 class RenderWithTemplateOptionController < LayoutTest
@@ -178,3 +191,4 @@ def test_symlinked_layout_is_rendered
     end
   end
 end
+