Returns hidden field tags for requested fields when they are present in params. Usually used to bypass params in GET-forms.
def hidden_params_fields(*fields)
inputs = fields.flat_map do |field|
next unless params.key?(field)
val = params[field]
if val.is_a?(Array)
name = "#{field}[]"
val.map { |str| [name, str] }
else
[[field, val]]
end
end
safe_join inputs.map { |(name, val)| hidden_field_tag name, val if name }
end