Hey all,
I looked at source code for fields_for:
def fields_for(record_name, record_object = nil, fields_options = {},
&block)
fields_options, record_object = record_object, nil if
record_object.is_a?(Hash) && record_object.extractable_options?
fields_options[:builder] ||= options[:builder]
fields_options[:parent_builder] = self
fields_options[:namespace] =
fields_options[:parent_builder].options[:namespace]
case record_name
when String, Symbol
if nested_attributes_association?(record_name)
return fields_for_with_nested_attributes(record_name,
record_object, fields_options, block)
end
else
record_object = record_name.is_a?(Array) ? record_name.last :
record_name
record_name = ActiveModel::Naming.param_key(record_object)
end
index = if options.has_key?(:index)
“[#{options[:index]}]”
elsif defined?(@auto_index)
self.object_name = @object_name.to_s.sub(%r[]$/,"")
“[#{@auto_index}]”
end
record_name = “#{object_name}#{index}[#{record_name}]”
@template.fields_for(record_name, record_object, fields_options,
&block)
end
Notice this part:
options[:builder]
this options hash is no where to be defined. In argument list, there’s
only a fields_options hash. Reason why this matters to me is because I
am trying to override this method in my application_helper.rb in order
to extend it.