Adding convenience method for accessing db from a document

lib/mongoid/collections/operations.rb

@@ -6,6 +6,7 @@ module Operations #:nodoc:
       # Mongo:Collection. This is used in delegation.
       READ = [
         :[],
+        :db,
         :count,
         :distinct,
         :find,

lib/mongoid/document.rb

@@ -21,11 +21,16 @@ def self.included(base)
         attr_accessor :association_name, :_parent
         attr_reader :new_record
 
-        delegate :collection, :embedded, :primary_key, :to => "self.class"
+        delegate :collection, :db, :embedded, :primary_key, :to => "self.class"
       end
     end
 
     module ClassMethods
+      # Return the database associated with this class.
+      def db
+        collection.db
+      end
+
       # Returns the collection associated with this +Document+. If the
       # document is embedded, there will be no collection associated
       # with it.
@@ -125,8 +130,6 @@ def ==(other)
       # Example:
       #
       # <tt>name.assimilate(person, options)</tt>
-      #
-      # Returns: The child +Document+.
       def assimilate(parent, options)
         parentize(parent, options.name); notify; self
       end
@@ -157,10 +160,6 @@ def identify
       # Options:
       #
       # attrs: The attributes +Hash+ to set up the document with.
-      #
-      # Example:
-      #
-      # <tt>Person.new(:title => "Mr", :age => 30)</tt>
       def initialize(attrs = nil)
         @attributes = {}
         process(attrs)
@@ -272,10 +271,6 @@ def to_param
       # child: The child +Document+ that sent the notification.
       # clear: Will clear out the child's attributes if set to true.
       #
-      # Example:
-      #
-      # <tt>person.notify_observers(self)</tt> will cause this method to execute.
-      #
       # This will also cause the observing +Document+ to notify it's parent if
       # there is any.
       def update(child, clear = false)

spec/integration/mongoid/document_spec.rb

@@ -6,6 +6,13 @@
     Person.delete_all
   end
 
+  describe "#db" do
+
+    it "returns the mongo database" do
+      Person.db.should == Mongoid.master
+    end
+  end
+
   context "when document contains a hash field" do
 
     before do

spec/unit/mongoid/document_spec.rb

@@ -99,6 +99,18 @@
 
   end
 
+  describe ".db" do
+
+    before do
+      @db = stub
+      @collection.expects(:db).returns(@db)
+    end
+
+    it "returns the database from the collection" do
+      Person.db.should == @db
+    end
+  end
+
   describe "#clone" do
 
     before do