Contents

require 'set'
require_relative '../../migration_helpers'

module Gitlab
  module Styles
    module Rubocop
      module Cop
        module Migration
          # Cop that prevents the use of hash indexes in database migrations
          class HashIndex < RuboCop::Cop::Cop
            include MigrationHelpers

            MSG = 'hash indexes should be avoided at all costs since they are not ' \
              'recorded in the PostgreSQL WAL, you should use a btree index instead'.freeze

            NAMES = Set.new([:add_index, :index, :add_concurrent_index]).freeze

            def on_send(node)
              return unless in_migration?(node)

              name = node.children[1]

              return unless NAMES.include?(name)

              opts = node.children.last

              return unless opts&.type == :hash

              opts.each_node(:pair) do |pair|
                next unless hash_key_type(pair) == :sym &&
                    hash_key_name(pair) == :using

                if hash_key_value(pair).to_s == 'hash'
                  add_offense(pair, :expression)
                end
              end
            end

            def hash_key_type(pair)
              pair.children[0].type
            end

            def hash_key_name(pair)
              pair.children[0].children[0]
            end

            def hash_key_value(pair)
              pair.children[1].children[0]
            end
          end
        end
      end
    end
  end
end

Version data entries

2 entries across 2 versions & 1 rubygems

Version	Path
gitlab-styles-1.0.0	lib/gitlab/styles/rubocop/cop/migration/hash_index.rb
gitlab-styles-0.1.0	lib/gitlab/styles/rubocop/cop/migration/hash_index.rb