Merge branch 'nil_associations' of https://github.com/jaronkk/mongoma…

…pper

* 'nil_associations' of https://github.com/jaronkk/mongomapper:
  Fixed an issue using the association_name= method to assign a new object updated existing pointers to the proxy, rather than generating a new one
  Modified accessor method for one and belongs_to associations to return nil rather than a proxy object if the association does not exist Added additional method calls for build_<name>, create_<name>, and create<name>! since calling .build(), .create(), and .create!() would raise when the association is nil. Discussion from http://groups.google.com/group/mongomapper/browse_thread/thread/e311dd04b0af576f

lib/mongo_mapper/plugins/associations.rb

@@ -33,19 +33,50 @@ def create_association(type, name, options, &extension)
             association = Associations::Base.new(type, name, options, &extension)
             associations[association.name] = association
 
-            define_method(association.name) do
-              get_proxy(association)
-            end
-
-            define_method("#{association.name}=") do |value|
-              get_proxy(association).replace(value)
-              value
-            end
-
             if association.one? || association.belongs_to?
+              define_method(association.name) do
+                proxy = get_proxy(association)
+                proxy.nil? ? nil : proxy
+              end
+
+              define_method("#{association.name}=") do |value|
+                proxy = get_proxy(association)
+
+                if (proxy.nil? || proxy.target != value)
+                  proxy = build_proxy(association)
+                end
+
+                proxy.replace(value)
+                value
+              end
+
               define_method("#{association.name}?") do
                 get_proxy(association).present?
               end
+
+              if (association.one?)
+                define_method("build_#{association.name}") do |*args|
+                  get_proxy(association).build(*args)
+                end
+
+                define_method("create_#{association.name}") do |*args|
+                  get_proxy(association).create(*args)
+                end
+
+                define_method("create_#{association.name}!") do |*args|
+                  get_proxy(association).create!(*args)
+                end
+              end
+            else
+              define_method(association.name) do
+                get_proxy(association)
+              end
+
+              define_method("#{association.name}=") do |value|
+                get_proxy(association).replace(value)
+                value
+              end
+
             end
 
             if association.options[:dependent] && association.many? && !association.embeddable?
@@ -75,11 +106,17 @@ def embedded_associations
             association
           end
         end
-
+
+        def build_proxy(association)
+          proxy = association.proxy_class.new(self, association)
+          self.instance_variable_set(association.ivar, proxy)
+
+          proxy
+        end
+
         def get_proxy(association)
           unless proxy = self.instance_variable_get(association.ivar)
-            proxy = association.proxy_class.new(self, association)
-            self.instance_variable_set(association.ivar, proxy)
+            proxy = build_proxy(association)
           end
           proxy
         end

lib/mongo_mapper/plugins/callbacks.rb

@@ -83,7 +83,9 @@ def run_callbacks(kind, options={}, &block)
           self.class.send(callback_chain_method).run(self, options, &block)
           self.embedded_associations.each do |association|
             if association.one?
-              self.send(association.name).run_callbacks(kind, options, &block)
+              if (!self.send("#{association.name}").nil?)
+                self.send(association.name).run_callbacks(kind, options, &block)
+              end
             else
               self.send(association.name).each do |document|
                 document.run_callbacks(kind, options, &block)

lib/mongo_mapper/plugins/document.rb

@@ -21,7 +21,9 @@ def reload
           if doc = collection.find_one(:_id => id)
             tap do |instance|
               instance.class.associations.each_key do |association_name|
-                send(association_name).reset if respond_to?(association_name)
+                if self.respond_to?(association_name) && !self.send(association_name).nil?
+                  self.send(association_name).reset
+                end
               end
               instance.attributes = doc
             end

test/functional/associations/test_belongs_to_polymorphic_proxy.rb

@@ -54,6 +54,7 @@ def setup
       @status.target = project
       @status.save.should be_true
       project.destroy
+      @status.reload
     end
 
     should "return nil instead of raising error" do

test/functional/associations/test_belongs_to_proxy.rb

@@ -14,6 +14,10 @@ def setup
   should "default to nil" do
     @comment_class.new.post.nil?.should be_true
   end
+
+  should "return nil instead of a proxy" do
+    nil.should === @comment_class.new.post
+  end
 
   should "have boolean presence method" do
     comment = @comment_class.new(:name => 'Foo!')
@@ -32,7 +36,27 @@ def setup
     comment.post.should == post
     comment.post.nil?.should be_false
   end
+
+  should "generate a new proxy when replacing the association" do 
+    post1 = @post_class.create(:name => 'post1')
+    post2 = @post_class.create(:name => 'post2')
+
+    comment = @comment_class.new(:name => 'Foo!', :post => post1)
+    comment.save.should be_true
+
 
+    comment = comment.reload
+    comment.post.should == post1
+    comment.post.nil?.should be_false
+
+    original_post = comment.post
+    original_post.name.should == 'post1'
+
+    comment.post = post2
+    comment.post.name.should == 'post2'
+    original_post.name.should == 'post1'
+  end
+
   should "unset the association" do
     post = @post_class.new(:name => 'mongomapper')
     comment = @comment_class.new(:name => 'Foo!', :post => post)

test/functional/associations/test_many_polymorphic_proxy.rb

@@ -138,6 +138,7 @@ def setup
       @hm2 = Message.create(:body => 'Hall the king!', :position => 2)
       @hall.messages = [@hm1, @hm2, @hm3]
       @hall.save
+      @hall.reload
     end
 
     context "dynamic finders" do

test/functional/associations/test_one_embedded_proxy.rb

@@ -20,7 +20,7 @@ def setup
     @post_class.one :author, :class => @author_class
 
     post = @post_class.create
-    author = post.author.build(:name => "John")
+    author = post.build_author(:name => "John")
     post.author.should be_instance_of(@author_class)
     post.author.should be_new
     post.author.name.should == 'John'

test/functional/associations/test_one_proxy.rb

@@ -13,6 +13,11 @@ def setup
     @post_class.new.author.nil?.should be_true
   end
 
+  should "return nil instead of a proxy" do
+    @post_class.one :author, :class => @author_class
+    nil.should === @post_class.new.author
+  end
+
   should "allow assignment of associated document using a hash" do
     @post_class.one :author, :class => @author_class
 
@@ -42,8 +47,28 @@ def setup
         post.author = new_author
         post.author.should == new_author
       end
-    end
+
+      should "generate a new proxy instead of modifying the existing one" do
+        @post_class.one :author, :class => @author_class
+
+        post = @post_class.new
+        author = @author_class.new(:name => 'Frank')
+        post.author = author
+        post.reload
 
+        post.author.should == author
+        post.author.nil?.should be_false
+
+        original_author = post.author
+        original_author.name.should == 'Frank'
+        new_author = @author_class.new(:name => 'Emily')
+        post.author = new_author
+        post.author.should == new_author
+
+        original_author.name.should == 'Frank'
+      end
+    end
+
     context "with a Hash" do
       should "convert to an object of the class and work" do
         @post_class.one :author, :class => @author_class
@@ -135,7 +160,7 @@ def setup
     @post_class.one :author, :class => @author_class
 
     post = @post_class.create
-    author = post.author.build(:name => 'John')
+    author = post.build_author(:name => 'John')
     post.author.should be_instance_of(@author_class)
     post.author.should be_new
     post.author.name.should == 'John'
@@ -147,7 +172,7 @@ def setup
     @post_class.one :author, :class => @author_class
 
     post = @post_class.create
-    author = post.author.create(:name => 'John')
+    author = post.create_author(:name => 'John')
     post.author.should be_instance_of(@author_class)
     post.author.should_not be_new
     post.author.name.should == 'John'
@@ -164,13 +189,13 @@ def setup
     should "raise exception if invalid" do
       post = @post_class.create
       assert_raises(MongoMapper::DocumentNotValid) do
-        post.author.create!
+        post.create_author!
       end
     end
 
     should "work if valid" do
       post = @post_class.create
-      author = post.author.create!(:name => 'John')
+      author = post.create_author!(:name => 'John')
       post.author.should be_instance_of(@author_class)
       post.author.should_not be_new
       post.author.name.should == 'John'

test/functional/test_associations.rb

@@ -36,6 +36,8 @@ class AwesomePost
     tag2 = AwesomeTag.new(:name => 'grand')
     post1 = AwesomePost.create(:creator => user, :tags => [tag1])
     post2 = AwesomePost.create(:creator => user, :tags => [tag2])
+
+    user.reload
     user.posts.should == [post1, post2]
 
     post1 = post1.reload

test/functional/test_identity_map.rb

@@ -426,7 +426,7 @@ class ::BlogPost < ::Item
 
       should "work correctly with one proxy create" do
         root = Item.create(:title => 'Root')
-        blog = root.blog.create(:title => 'Blog')
+        blog = root.create_blog(:title => 'Blog')
         blog.parent.should equal(root)
       end
     end