Move the bulk alter table code into the abstract mysql adapter, hence it is supported for mysql2 as well now.

activerecord/CHANGELOG

@@ -1,5 +1,7 @@
 *Rails 3.2.0 (unreleased)*
 
+* Support bulk change_table in mysql2 adapter, as well as the mysql one. [Jon Leighton]
+
 * If multiple parameters are sent representing a date, and some are blank, the
 resulting object is nil. In previous releases those values defaulted to 1. This
 only affects existing but blank parameters, missing ones still raise an error.

activerecord/lib/active_record/connection_adapters/abstract_mysql_adapter.rb

@@ -140,6 +140,10 @@ module ActiveRecord
         true
       end
 
+      def supports_bulk_alter? #:nodoc:
+        true
+      end
+
       def native_database_types
         NATIVE_DATABASE_TYPES
       end
@@ -401,6 +405,21 @@ module ActiveRecord
         super(table_name, options.reverse_merge(:options => "ENGINE=InnoDB"))
       end
 
+      def bulk_change_table(table_name, operations) #:nodoc:
+        sqls = operations.map do |command, args|
+          table, arguments = args.shift, args
+          method = :"#{command}_sql"
+
+          if respond_to?(method)
+            send(method, table, *arguments)
+          else
+            raise "Unknown method called : #{method}(#{arguments.inspect})"
+          end
+        end.flatten.join(", ")
+
+        execute("ALTER TABLE #{quote_table_name(table_name)} #{sqls}")
+      end
+
       # Renames a table.
       #
       # Example:
@@ -552,6 +571,29 @@ module ActiveRecord
         rename_column_sql
       end
 
+      def remove_column_sql(table_name, *column_names)
+        columns_for_remove(table_name, *column_names).map {|column_name| "DROP #{column_name}" }
+      end
+      alias :remove_columns_sql :remove_column
+
+      def add_index_sql(table_name, column_name, options = {})
+        index_name, index_type, index_columns = add_index_options(table_name, column_name, options)
+        "ADD #{index_type} INDEX #{index_name} (#{index_columns})"
+      end
+
+      def remove_index_sql(table_name, options = {})
+        index_name = index_name_for_remove(table_name, options)
+        "DROP INDEX #{index_name}"
+      end
+
+      def add_timestamps_sql(table_name)
+        [add_column_sql(table_name, :created_at, :datetime), add_column_sql(table_name, :updated_at, :datetime)]
+      end
+
+      def remove_timestamps_sql(table_name)
+        [remove_column_sql(table_name, :updated_at), remove_column_sql(table_name, :created_at)]
+      end
+
       private
 
       def supports_views?

activerecord/lib/active_record/connection_adapters/mysql_adapter.rb

@@ -97,11 +97,6 @@ module ActiveRecord
         connect
       end
 
-      # FIXME: Move to abstract adapter
-      def supports_bulk_alter? #:nodoc:
-        true
-      end
-
       # Returns true, since this connection adapter supports prepared statement
       # caching.
       def supports_statement_cache?
@@ -312,48 +307,6 @@ module ActiveRecord
         # Transactions aren't supported
       end
 
-      # SCHEMA STATEMENTS ========================================
-
-      def bulk_change_table(table_name, operations) #:nodoc:
-        sqls = operations.map do |command, args|
-          table, arguments = args.shift, args
-          method = :"#{command}_sql"
-
-          if respond_to?(method)
-            send(method, table, *arguments)
-          else
-            raise "Unknown method called : #{method}(#{arguments.inspect})"
-          end
-        end.flatten.join(", ")
-
-        execute("ALTER TABLE #{quote_table_name(table_name)} #{sqls}")
-      end
-
-      protected
-
-      def remove_column_sql(table_name, *column_names)
-        columns_for_remove(table_name, *column_names).map {|column_name| "DROP #{column_name}" }
-      end
-      alias :remove_columns_sql :remove_column
-
-      def add_index_sql(table_name, column_name, options = {})
-        index_name, index_type, index_columns = add_index_options(table_name, column_name, options)
-        "ADD #{index_type} INDEX #{index_name} (#{index_columns})"
-      end
-
-      def remove_index_sql(table_name, options = {})
-        index_name = index_name_for_remove(table_name, options)
-        "DROP INDEX #{index_name}"
-      end
-
-      def add_timestamps_sql(table_name)
-        [add_column_sql(table_name, :created_at, :datetime), add_column_sql(table_name, :updated_at, :datetime)]
-      end
-
-      def remove_timestamps_sql(table_name)
-        [remove_column_sql(table_name, :updated_at), remove_column_sql(table_name, :created_at)]
-      end
-
       private
 
       def exec_stmt(sql, name, binds)