adding inherit attribute to if_content and unless_content

app/models/standard_tags.rb

@@ -275,9 +275,10 @@ class TagError < StandardError; end
   end
 
   desc %{ 
-    Renders the containing elements only if all of the listed parts exists on a page.
+    Renders the containing elements only if all of the listed parts exist on a page.
     By default the @part@ attribute is set to @body@, but you may list more than one
-    part by seprating them with a comma.
+    part by seprating them with a comma. Setting the optional @inherit@ to true will 
+    search ancestors independently for each part. By default @inherit@ is set to @false@.
     
     *Usage:*
     <pre><code><r:if_content [part="part_name, other_part"]>...</r:if_content></code></pre>
@@ -286,10 +287,18 @@ class TagError < StandardError; end
     page = tag.locals.page
     part_name = tag_part_name(tag)
     parts_arr = part_name.split(',')
+    inherit_attr = tag.attr['inherit'] || 'false'
+    inherit = inherit_attr.downcase == 'true' ? true : false
     all_parts_present = true
+    part_page = page
     parts_arr.each do |name|
       name.strip!
-      all_parts_present = false if page.part(name).nil?
+      if inherit
+        while (part_page.part(name).nil? and (not part_page.parent.nil?)) do
+          part_page = part_page.parent
+        end
+      end
+      all_parts_present = false if part_page.part(name).nil?
     end
     tag.expand if all_parts_present
   end
@@ -305,10 +314,18 @@ class TagError < StandardError; end
     page = tag.locals.page
     part_name = tag_part_name(tag)
     parts_arr = part_name.split(',')
+    inherit_attr = tag.attr['inherit'] || 'false'
+    inherit = inherit_attr.downcase == 'true' ? true : false
     all_parts_present = false
+    part_page = page
     parts_arr.each do |name|
       name.strip!
-      all_parts_present = true if !page.part(name).nil?
+      if inherit
+        while (part_page.part(name).nil? and (not part_page.parent.nil?)) do
+          part_page = part_page.parent
+        end
+      end
+      all_parts_present = true if !part_page.part(name).nil?
     end
     tag.expand unless all_parts_present
   end

spec/models/standard_tags_spec.rb

@@ -249,6 +249,16 @@
   end
 
   describe "<r:if_content>" do
+    describe "with inherit attribute set to 'true'" do
+      it 'should render the contained block if the current or ancestor pages have the specified parts' do
+        page(:guests).should render('<r:if_content part="favors, extended" inherit="true">true</r:if_content>').as('true')
+      end
+
+      it 'should not render the contained block if the current or ancestor pages do not have all of the specified parts' do
+        page(:guests).should render('<r:if_content part="favors, madeup" inherit="true">true</r:if_content>').as('')
+      end
+    end
+
     it "without 'part' attribute should render the contained block if the 'body' part exists" do
       page.should render('<r:if_content>true</r:if_content>').as('true')
     end
@@ -271,6 +281,15 @@
   end
 
   describe "<r:unless_content>" do
+    describe "with inherit attribute set to 'true'" do
+      it 'should not render the contained block if the current or ancestor pages have the specified parts' do
+        page(:guests).should render('<r:unless_content part="favors, extended" inherit="true">true</r:unless_content>').as('')
+      end
+
+      it 'should render the contained block if the current or ancestor pages do not have the specified parts' do
+        page(:guests).should render('<r:unless_content part="madeup, imaginary" inherit="true">true</r:unless_content>').as('true')
+      end
+    end
     it "without 'part' attribute should not render the contained block if the 'body' part exists" do
       page.should render('<r:unless_content>false</r:unless_content>').as('')
     end

spec/scenarios/pages_scenario.rb

@@ -46,6 +46,10 @@ def load
       create_page_part "unless_dev", :content => "<r:unless_dev>not dev</r:unless_dev>"
     end
     create_page "Virtual", :class_name => "VirtualPage", :virtual => true
+    create_page "Party" do
+      create_page_part "favors"
+      create_page "Guests"
+    end
   end
 
 end