class ActiveRecord::Migration::Compatibility::V4_2

def add_reference(table_name, ref_name, **options)
  options[:index] ||= false
  super
end

def add_timestamps(table_name, **options)
  options[:null] = true if options[:null].nil?
  super
end

def compatible_table_definition(t)
  class << t
    prepend TableDefinition
  end
  super
end

def index_exists?(table_name, column_name, **options)
  column_names = Array(column_name).map(&:to_s)
  options[:name] =
    if options[:name].present?
      options[:name].to_s
    else
      connection.index_name(table_name, column: column_names)
    end
  super
end

def index_name_for_remove(table_name, column_name, options)
  index_name = connection.index_name(table_name, column_name || options)
  unless connection.index_name_exists?(table_name, index_name)
    if options.key?(:name)
      options_without_column = options.except(:column)
      index_name_without_column = connection.index_name(table_name, options_without_column)
      if connection.index_name_exists?(table_name, index_name_without_column)
        return index_name_without_column
      end
    end
    raise ArgumentError, "Index name '#{index_name}' on table '#{table_name}' does not exist"
  end
  index_name
end

def remove_index(table_name, column_name = nil, **options)
  options[:name] = index_name_for_remove(table_name, column_name, options)
  super
end