A patch for spatial data support for rails's mysql2 adapter, only support `point` geometry data

mysql2spatial.rb

require 'geo_ruby/ewk'

# NOTE: Set SRID 0 as same as mysql's default
GeoRuby::SimpleFeatures::DEFAULT_SRID = 0

module ActiveRecord
  module Type
    class Spatial < Value
      def type
        :spatial
      end

      private

      def cast_value(value)
        return value unless value.is_a?(::String)

        GeoRuby::SimpleFeatures::Geometry.from_ewkb(value[4..-1]) rescue value
      end
    end
  end

  module ConnectionAdapters
    class Mysql2Adapter
      def quote_with_spatial(value_, column_ = nil)
        if value_.is_a?(GeoRuby::SimpleFeatures::Point)
          "GeomFromWKB(0x#{value_.as_hex_wkb},#{value_.srid})"
        elsif column_ && column_.type == :spatial && value_.is_a?(String)
          # NOTE: For fixture
          value_
        else
          quote_without_spatial(value_, column_)
        end
      end
      alias_method_chain :quote, :spatial

      def initialize_type_map_with_spatial(m)
        initialize_type_map_without_spatial(m)
        # NOTE: Only support `point` geometry data
        m.register_type(%r(point)i) { |sql_type| ActiveRecord::Type::Spatial.new }
      end
      alias_method_chain :initialize_type_map, :spatial
    end
  end
end

ActiveRecord::Base.connection.clear_cache! # NOTE: To `reload_type_map` that reload column types