Array of points error

bug_array_of_points.rb

# Activate the gem you are reporting the issue against.
gem 'activerecord', '4.2.1'
require 'active_record'
require 'minitest/autorun'
require 'logger'

# Ensure backward compatibility with Minitest 4
Minitest::Test = MiniTest::Unit::TestCase unless defined?(Minitest::Test)

# This connection will do for database-independent bug reports.
ActiveRecord::Base.establish_connection(adapter: 'postgresql', database: 'TODO', 
                                        username: 'TODO', password: 'TODO')
ActiveRecord::Base.logger = Logger.new(STDOUT)

ActiveRecord::Schema.define do
  drop_table :shapes rescue nil
  create_table :shapes do |t|
    t.column :centroid, :point
    t.column :polygon, :point, array: true
  end
end

class Shape < ActiveRecord::Base
end

class ArrayOfPointsTest < Minitest::Test

  def test_point # Succeeds
    Shape.create!(centroid: [0.4, 0.7])
  end

  def test_array_of_points # Fails
    Shape.create!(polygon: [[0.1, 0.2],
                            [0.3, 0.4],
                            [0.5, 0.6],
                            [0.7, 0.8],
                            [0.1, 0.2]])
  end
  
end

patch_rails_4.rb

ActiveRecord::ConnectionAdapters::PostgreSQL::OID::Array.class_eval do

  def cast_value_for_database(value)
    if value.is_a?(::Array)
      
      if subtype.type == :point
        
        casted_values = value.map do |item|
          if item.is_a?(::Array) && !item.first.is_a?(Array)
            quote_and_escape(subtype.type_cast_for_database(item))
          else
            cast_value_for_database(item)
          end
        end
        "{#{casted_values.join(delimiter)}}"
        
      else
        casted_values = value.map { |item| cast_value_for_database(item) }
        "{#{casted_values.join(delimiter)}}"
      end
    else
      quote_and_escape(subtype.type_cast_for_database(value))
    end
  end

end

patch_rails_5.rb

ActiveRecord::ConnectionAdapters::PostgreSQL::OID::Array.class_eval do

  def type_cast_array(value, method)
    if value.is_a?(::Array)

      if @subtype.type == :point

        value.map do |item|
          if item.is_a?(::Array) && !item.first.is_a?(Array)
            @subtype.public_send(method, item)
          else
            type_cast_array(item, method)
          end
        end

      else
        value.map { |item| type_cast_array(item, method) }
      end

    else
      @subtype.public_send(method, value)
    end
  end

end