Custom filters list applies only first filter

[ruslankhaertdinov]

Looks like in current implementation (ver. 0.5.0) only first filter from the custom_filters list added to the @_allowed_custom_filters. In this method elsif condition doesn't work properly.

module JSONAPI::Utils::Support::Filter
  module Custom
    ...

    def custom_filter(attr)
      attr = attr.to_sym
      @_allowed_filters[attr] = {}

      if !@_allowed_custom_filters.is_a?(Array)
        @_allowed_custom_filters = Array(attr)
      elsif @_allowed_custom_filters.include?(attr)
        @_allowed_custom_filters.push(attr)
      end
    end
  end
end

[ruslankhaertdinov]

@tiagopog Hi! Thanks a lot for so useful gem, and please take a look to this issue and related PR.

Thanks, Ruslan

[tiagopog]

You're right, it seems like there's a missing ! in the expression @_allowed_custom_filters.include?(attr). I'll take a look at the PR asap.