RSpec: Separates id series for each table so that tests does not accidentally pass when rows in different tables have the same ID

separate_id_series.rb

class RSpec::SeparateIdSeries
  # Separates id series for each table so that tests does not
  # accidentally pass when rows in different tables have the same ID
  def self.setup
    # This takes almost a second when using spork for some reason, so skipping it there.
    return if Spork.using_spork?

    t = Time.now

    tables.each_with_index do |table, i|
      Item.connection.execute("ALTER SEQUENCE #{table}_id_seq RESTART WITH #{100000 * (i+1)}")
    end

    reset_time = Time.now - t
    p "Long set id series time: #{reset_time}" if reset_time > 0.5
  end

  def self.tables
    Item.connection.execute("select tablename from pg_tables;").to_a.
      map { |x| x["tablename"] }.
      find_all { |x| !x.include?("pg_") && !x.include?("sql_") && !x.include?("schema_") }
  end
end

# in config.before(:suite) do
# RSpec::SeparateIdSeries.setup

The problem this attempts to solve is if you for example have two models, Foo and Bar that is usally created at the same time, they get the same incrementing ID. If you accidentally check for Bar ids when a method return Foo ids, it will pass most of the time by accident.