From afecd0c58b746d64241fb0f44235391132ad28c8 Mon Sep 17 00:00:00 2001
From: Brandon Keepers <brandon@opensoul.org>
Date: Sat, 3 Sep 2011 00:18:12 -0400
Subject: [PATCH] Unset all instance variables when reloading

---
 lib/mongo_mapper/plugins/document.rb | 11 +++++------
 lib/mongo_mapper/plugins/keys.rb     | 10 ----------
 test/functional/test_document.rb     |  5 +++++
 3 files changed, 10 insertions(+), 16 deletions(-)

diff --git a/lib/mongo_mapper/plugins/document.rb b/lib/mongo_mapper/plugins/document.rb
index 0cb693784..735beb5df 100644
--- a/lib/mongo_mapper/plugins/document.rb
+++ b/lib/mongo_mapper/plugins/document.rb
@@ -21,13 +21,12 @@ def destroyed?
 
         def reload
           if doc = collection.find_one(:_id => id)
-            tap do |instance|
-              instance.class.associations.each_value do |association|
-                get_proxy(association).reset
-              end
-              instance.clear_keys!
-              instance.attributes = doc
+            self.class.associations.each_value do |association|
+              get_proxy(association).reset
             end
+            instance_variables.each { |ivar| instance_variable_set(ivar, nil) }
+            self.attributes = doc
+            self
           else
             raise DocumentNotFound, "Document match #{_id.inspect} does not exist in #{collection.name} collection"
           end
diff --git a/lib/mongo_mapper/plugins/keys.rb b/lib/mongo_mapper/plugins/keys.rb
index 908f3c650..7951286ea 100644
--- a/lib/mongo_mapper/plugins/keys.rb
+++ b/lib/mongo_mapper/plugins/keys.rb
@@ -172,16 +172,6 @@ def persisted?
           !new? && !destroyed?
         end
 
-        def clear_keys!
-          keys.each_key do |key|
-            if respond_to?(:"#{key}=")
-              self.send(:"#{key}=", nil)
-            else
-              self[key] = nil
-            end
-          end
-        end
-
         def attributes=(attrs)
           return if attrs.blank?
 
diff --git a/test/functional/test_document.rb b/test/functional/test_document.rb
index 220141adf..4579ce20a 100644
--- a/test/functional/test_document.rb
+++ b/test/functional/test_document.rb
@@ -245,6 +245,11 @@ def setup
       @instance.destroy
       assert_raises(MongoMapper::DocumentNotFound) { @instance.reload }
     end
+
+    should "clear keys that were removed from the database" do
+      @instance.unset(:age)
+      @instance.reload.age.should be_nil
+    end
   end
 
   context "database has keys not defined in model" do