Fixed that has_many collections shouldn't load the entire association to do build or create [DHH]

git-svn-id: http://svn-commit.rubyonrails.org/rails/trunk@4354 5ecf4fe2-1ee6-0310-87b1-e25e094e27de

2 files changed, 35 insertions, 3 deletions

diff --git a/activerecord/lib/active_record/associations/association_collection.rb b/activerecord/lib/active_record/associations/association_collection.rb
index 428152eea0..9c27411a3e 100644
--- a/activerecord/lib/active_record/associations/association_collection.rb
+++ b/activerecord/lib/active_record/associations/association_collection.rb
@@ -95,7 +95,14 @@ module ActiveRecord
       # calling collection.size if it has. If it's more likely than not that the collection does have a size larger than zero
       # and you need to fetch that collection afterwards, it'll take one less SELECT query if you use length.
       def size
-        if loaded? && !@reflection.options[:uniq] then @target.size else count_records end
+        if loaded? && !@reflection.options[:uniq]
+          @target.size
+        elsif !loaded? && !@reflection.options[:uniq] && @target.is_a?(Array)
+          unsaved_records = Array(@target.detect { |r| r.new_record? }).size
+          unsaved_records + count_records
+        else
+          count_records
+        end
       end
 
       # Returns the size of the collection by loading it and calling size on the array. If you want to use this method to check
diff --git a/activerecord/lib/active_record/associations/has_many_association.rb b/activerecord/lib/active_record/associations/has_many_association.rb
index 912e0aa390..6a2089c7b8 100644
--- a/activerecord/lib/active_record/associations/has_many_association.rb
+++ b/activerecord/lib/active_record/associations/has_many_association.rb
@@ -10,10 +10,16 @@ module ActiveRecord
         if attributes.is_a?(Array)
           attributes.collect { |attr| build(attr) }
         else
-          load_target
           record = @reflection.klass.new(attributes)
           set_belongs_to_association_for(record)
-          @target << record
+          
+          if loaded?
+            @target << record
+          else
+            @target ||= []
+            @target << record
+          end
+          
           record
         end
       end
@@ -107,6 +113,25 @@ module ActiveRecord
           end
         end
 
+        def load_target
+          if !@owner.new_record? || foreign_key_present
+            begin
+              if !loaded?
+                if @target.is_a?(Array) && @target.any?
+                  @target = find_target + @target
+                else
+                  @target = find_target
+                end
+              end
+            rescue ActiveRecord::RecordNotFound
+              reset
+            end
+          end
+
+          loaded if target
+          target
+        end
+
         def count_records
           count = if has_cached_counter?
             @owner.send(:read_attribute, cached_counter_attribute_name)