added if_attachments tag (works like if_children)

app/models/page_attachment_associations.rb

@@ -1,18 +1,7 @@
 module PageAttachmentAssociations
   def self.included(base)
     base.class_eval {
-      has_many :attachments, :class_name => "PageAttachment", :dependent => :destroy, :order => 'position' do
-        def by_extensions(extensions, options={})
-          conditions = unless extensions.blank?
-            [ extensions.map { |ext| "page_attachments.filename LIKE ?"}.join(' OR '), 
-              *extensions.map { |ext| "%#{ext}" } ]
-          else
-            nil
-          end
-          find(:all, options.merge(:conditions => conditions))
-        end
-      end
-
+      has_many :attachments, :class_name => "PageAttachment", :dependent => :destroy, :order => 'position'
       attr_accessor :add_attachments
       after_save :save_attachments
       include InstanceMethods
@@ -28,14 +17,13 @@ def attachment(name)
 
     def save_attachments
       if @add_attachments && ! @add_attachments['file'].blank?
-		i = 0
+		    i = 0
         @add_attachments['file'].each do |page_attach|
           attachments << PageAttachment.new(
-			  :uploaded_data => page_attach, 
-			  :title => @add_attachments['title'][i],
-			  :description => @add_attachments['description'][i]
-		  )
-		  i += 1
+			                    :uploaded_data => page_attach, 
+                  			  :title => @add_attachments['title'][i],
+                  			  :description => @add_attachments['description'][i])
+  		    i += 1
         end  
       end
       @add_attachments = nil

app/models/page_attachment_tags.rb

@@ -180,18 +180,28 @@ class TagError < StandardError; end
   }
   tag "attachment:each" do |tag|
     page = tag.locals.page
-  	order = tag.attr["order"] || "asc"
-    by = tag.attr["by"] || "position"
-    limit = tag.attr["limit"] || nil
-    offset = tag.attr["offset"] || nil
-    extensions = tag.attr["extensions"] && tag.attr["extensions"].split('|') || []
+
     returning String.new do |output|
-      page.attachments.by_extensions(extensions, :order => [by, order].join(" "), :limit => limit, :offset => offset).each do |att|
+      page.attachments.find(:all, attachments_find_options(tag)).each do |att|
         tag.locals.attachment = att
         output << tag.expand
       end
     end
-  end  
+  end
+
+  desc %{
+    Renders the contained elements only if the current contextual page has one or
+    more attachments. The @min_count@ attribute specifies the minimum number of required
+    attachments. You can also filter by extensions with the @extensions@ attribute.
+    
+    *Usage:*
+    <pre><code><r:if_attachments [min_count="n"] [extensions="doc|pdf"]>...</r:if_attachments></code></pre>
+  }
+  tag "if_attachments" do |tag|
+    count = tag.attr['min_count'] && tag.attr['min_count'].to_i || 0
+    attachments = tag.locals.page.attachments.count(:conditions => attachments_find_options(tag)[:conditions])
+    tag.expand if attachments >= count
+  end
 
   desc %{
     Renders the 'extension' virtual attribute of the attachment, extracted from filename.
@@ -213,4 +223,27 @@ class TagError < StandardError; end
     attachment = tag.locals.attachment
     attachment.filename[/\.(\w+)$/, 1]
   end
+
+  private
+    def attachments_find_options(tag)
+      attr = tag.attr.symbolize_keys
+
+      extensions = attr[:extensions] && attr[:extensions].split('|') || []
+      conditions = unless extensions.blank?
+        [ extensions.map { |ext| "page_attachments.filename LIKE ?"}.join(' OR '), 
+          *extensions.map { |ext| "%.#{ext}" } ]
+      else
+        nil
+      end
+
+      by = attr[:by] || "position"
+      order = attr[:order] || "asc"
+
+      options = {
+        :order => "#{by} #{order}",
+        :limit => attr[:limit] || nil,
+        :offset => attr[:offset] || nil,
+        :conditions => conditions
+      }
+    end
 end

test/functional/page_attachments_extension_test.rb

@@ -132,6 +132,12 @@ def test_filter_by_extension
     assert_renders "rails.png", %{<r:attachment:each extensions="png"><r:filename/></r:attachment:each>}
     assert_renders "rails.pngfoo.txt", %{<r:attachment:each extensions="png|txt"><r:filename/></r:attachment:each>}
   end
+
+  def test_if_attachment_tag
+    assert_renders "content", %{<r:if_attachments>content</r:if_attachments>}
+    assert_renders "", %{<r:if_attachments min_count="3">content</r:if_attachments>}
+    assert_renders "content", %{<r:if_attachments min_count="1" extensions="png">content</r:if_attachments>}
+  end
 
   def test_extension_tag
     assert_renders "pngtxt", %{<r:attachment:each><r:extension/></r:attachment:each>}