Reversing the changes done in c278a2c5 while still resolving #1857.

The changes broke bulk migration tests and were fixed in 4d256bc6;
however that brought back the issue of #1857 and so this commit goes
back to the original scenario and just adds change_table to the list
of methods which are to be recorded in the CommandRecorder. The
method_missing now delegates all calls to the underlying connection as
before.

activerecord/lib/active_record/migration/command_recorder.rb

@@ -48,7 +48,7 @@ def respond_to?(*args) # :nodoc:
         super || delegate.respond_to?(*args)
       end
 
-      [:create_table, :rename_table, :add_column, :remove_column, :rename_index, :rename_column, :add_index, :remove_index, :add_timestamps, :remove_timestamps, :change_column, :change_column_default].each do |method|
+      [:create_table, :change_table, :rename_table, :add_column, :remove_column, :rename_index, :rename_column, :add_index, :remove_index, :add_timestamps, :remove_timestamps, :change_column, :change_column_default].each do |method|
         class_eval <<-EOV, __FILE__, __LINE__ + 1
           def #{method}(*args)          # def create_table(*args)
             record(:"#{method}", args)  #   record(:create_table, args)
@@ -93,15 +93,11 @@ def invert_add_timestamps(args)
         [:remove_timestamps, args]
       end
 
-      # Record all the methods called in the +change+ method of a migration.
-      # This will ensure that IrreversibleMigration is raised when the corresponding
-      # invert_method does not exist while the migration is rolled back.
+      # Forwards any missing method call to the \target.
       def method_missing(method, *args, &block)
-        if delegate.respond_to?(method)
-          delegate.send(method, *args, &block)
-        else
-          record(method, args)
-        end
+        @delegate.send(method, *args, &block)
+      rescue NoMethodError => e
+        raise e, e.message.sub(/ for #<.*$/, " via proxy for #{@delegate}")
       end
 
     end

activerecord/test/cases/migration/command_recorder_test.rb

@@ -14,11 +14,9 @@ def america; end
         assert recorder.respond_to?(:america)
       end
 
-      def test_non_existing_method_records_and_raises_on_inversion
-        @recorder.send(:non_existing_method, :horses)
-        assert_equal 1, @recorder.commands.length
-        assert_raises(ActiveRecord::IrreversibleMigration) do
-          @recorder.inverse
+      def test_send_calls_super
+        assert_raises(NoMethodError) do
+          @recorder.send(:non_existing_method, :horses)
         end
       end