module DatabaseCleaner::Generic::Truncation

def clean
  raise NotImplementedError
end

def initialize(opts={})
  if !opts.empty? && !(opts.keys - [:only, :except, :pre_count, :reset_ids, :cache_tables]).empty?
    raise ArgumentError, "The only valid options are :only, :except, :pre_count, :reset_ids or :cache_tables. You specified #{opts.keys.join(',')}."
  end
  if opts.has_key?(:only) && opts.has_key?(:except)
    raise ArgumentError, "You may only specify either :only or :except.  Doing both doesn't really make sense does it?"
  end
  @only = opts[:only]
  @tables_to_exclude = Array( (opts[:except] || []).dup ).flatten
  @tables_to_exclude += migration_storage_names
  @pre_count = opts[:pre_count]
  @reset_ids = opts[:reset_ids]
  @cache_tables = opts.has_key?(:cache_tables) ? !!opts[:cache_tables] : true
end

def migration_storage_names
  %w[]
end

def start
  #included for compatability reasons, do nothing if you don't need to
end

def tables_to_truncate
  raise NotImplementedError
end