2 files changed, 36 insertions, 0 deletions
diff --git a/activerecord/lib/rails/generators/active_record/migration/migration_generator.rb b/activerecord/lib/rails/generators/active_record/migration/migration_generator.rb
new file mode 100644
index 0000000000..f6159deeeb
--- /dev/null
+++ b/activerecord/lib/rails/generators/active_record/migration/migration_generator.rb
@@ -0,0 +1,25 @@
+require 'rails/generators/active_record'
+
+module ActiveRecord
+  module Generators
+    class MigrationGenerator < Base
+      argument :attributes, :type => :array, :default => [], :banner => "field:type field:type"
+
+      def create_migration_file
+        set_local_assigns!
+        migration_template "migration.rb", "db/migrate/#{file_name}.rb"
+      end
+
+      protected
+        attr_reader :migration_action
+
+        def set_local_assigns!
+          if file_name =~ /^(add|remove)_.*_(?:to|from)_(.*)/
+            @migration_action = $1
+            @table_name       = $2.pluralize
+          end
+        end
+
+    end
+  end
+end
diff --git a/activerecord/lib/rails/generators/active_record/migration/templates/migration.rb b/activerecord/lib/rails/generators/active_record/migration/templates/migration.rb
new file mode 100644
index 0000000000..bbb7c53d86
--- /dev/null
+++ b/activerecord/lib/rails/generators/active_record/migration/templates/migration.rb
@@ -0,0 +1,11 @@
+class <%= migration_class_name %> < ActiveRecord::Migration
+  def self.up<% attributes.each do |attribute| %>
+    <%= migration_action %>_column :<%= table_name %>, :<%= attribute.name %><% if migration_action == 'add' %>, :<%= attribute.type %><% end -%>
+  <%- end %>
+  end
+
+  def self.down<% attributes.reverse.each do |attribute| %>
+    <%= migration_action == 'add' ? 'remove' : 'add' %>_column :<%= table_name %>, :<%= attribute.name %><% if migration_action == 'remove' %>, :<%= attribute.type %><% end -%>
+  <%- end %>
+  end
+end