Enable IdentityMap when generating new apps.

2 files changed, 17 insertions, 0 deletions

diff --git a/railties/lib/rails/generators/rails/app/templates/config/application.rb b/railties/lib/rails/generators/rails/app/templates/config/application.rb
index 6e515756fe..b7f64af339 100644
--- a/railties/lib/rails/generators/rails/app/templates/config/application.rb
+++ b/railties/lib/rails/generators/rails/app/templates/config/application.rb
@@ -57,5 +57,10 @@ module <%= app_const_base %>
 
     # Configure sensitive parameters which will be filtered from the log file.
     config.filter_parameters += [:password]
+
+<% unless options[:skip_active_record] -%>
+    # Enable IdentityMap for Active Record, to disable set to false or remove the line below.
+    config.active_record.identity_map = true
+<% end -%>
   end
 end
diff --git a/railties/test/isolation/abstract_unit.rb b/railties/test/isolation/abstract_unit.rb
index 3b03e4eb3d..3a582f850f 100644
--- a/railties/test/isolation/abstract_unit.rb
+++ b/railties/test/isolation/abstract_unit.rb
@@ -215,6 +215,17 @@ module TestHelpers
       end
     end
 
+    def remove_from_config(str)
+      application_file = "#{app_path}/config/application.rb"
+      environment = File.read(application_file)
+      lines = File.readlines(application_file)
+      if environment =~ /(\n\s*end\s*end\s*)\Z/
+        File.open(application_file, 'w') do |f|
+          lines.each {|line| f.puts(line) unless line =~ /#{str}/ }
+        end
+      end
+    end
+
     def app_file(path, contents)
       FileUtils.mkdir_p File.dirname("#{app_path}/#{path}")
       File.open("#{app_path}/#{path}", 'w') do |f|
@@ -231,6 +242,7 @@ module TestHelpers
                     :activemodel,
                     :activerecord,
                     :activeresource] - arr
+      remove_from_config "config.active_record" if to_remove.include? :activerecord
       $:.reject! {|path| path =~ %r'/(#{to_remove.join('|')})/' }
     end