Added scope chaining.

lib/mongo_mapper/plugins/querying/decorator.rb

@@ -30,6 +30,20 @@ def first(opts={})
         def last(opts={})
           model.load(super)
         end
+
+        private
+          def method_missing(method, *args, &block)
+            if model.respond_to?(method)
+              query = model.send(method, *args, &block)
+              if query.is_a?(Plucky::Query)
+                merge(query)
+              else
+                super
+              end
+            else
+              super
+            end
+          end
       end
     end
   end

test/functional/test_scopes.rb

@@ -35,7 +35,7 @@ class ScopesTest < Test::Unit::TestCase
         docs[0].name.should == 'John'
       end
     end
-    
+
     context "dynamic scopes" do
       setup do
         @document.class_eval do
@@ -51,7 +51,7 @@ class ScopesTest < Test::Unit::TestCase
         docs.size.should == 1
         docs.first.name.should == 'John'
       end
-      
+
       should "work with multiple arguments" do
         @document.create(:name => 'John', :age => 60)
         @document.create(:name => 'Frank', :age => 50)
@@ -61,5 +61,55 @@ class ScopesTest < Test::Unit::TestCase
         docs.map(&:name).sort.should == %w(Frank John)
       end
     end
+
+    context "chaining" do
+      setup do
+        @document.class_eval do
+          scope :by_age,  lambda { |age| {:age => age} }
+          scope :by_name, lambda { |name| {:name => name} }
+        end
+      end
+
+      should "work with scope methods" do
+        @document.create(:name => 'John', :age => 60)
+        @document.create(:name => 'Frank', :age => 60)
+        @document.create(:name => 'Bill', :age => 50)
+        docs = @document.by_age(60).by_name('John').all
+        docs.size.should == 1
+        docs.first.name.should == 'John'
+      end
+
+      should "work on query methods" do
+        @document.create(:name => 'John', :age => 60)
+        @document.create(:name => 'John', :age => 50)
+        @document.create(:name => 'Bill', :age => 50)
+        docs = @document.where(:name => 'John').by_age(50).all
+        docs.size.should == 1
+        docs.first.age.should == 50
+      end
+
+      should "work if method on model returns a query" do
+        @document.create(:name => 'John', :age => 10)
+        @document.create(:name => 'John', :age => 20)
+        @document.class_eval do
+          def self.young
+            query(:age.lte => 12)
+          end
+        end
+        docs = @document.by_name('John').young.all
+        docs.size.should == 1
+        docs.first.age.should == 10
+      end
+
+      should "not work if method on model, but return not a query" do
+        @document.class_eval do
+          def self.age
+            20
+          end
+        end
+
+        lambda { @document.by_name('John').age }.should raise_error(NoMethodError)
+      end
+    end
   end
 end