require 'rails_helper'

module Tables
  RSpec.describe Swap do
    describe '#each' do
      let(:initial_solution) do
        Distribution.new(min_per_table: 2, max_per_table: 2).tap do |distribution|
          distribution.tables << %i[a b]
          distribution.tables << %i[c d]
        end
      end

      let(:swaps) do
        acc = []
        described_class.new(initial_solution).each do |solution|
          acc << solution.tables.map(&:dup)
        end
        acc
      end

      it 'yields all possible swaps' do
        expect(swaps.count).to eq(4)
      end

      it 'swaps the people' do
        expect(swaps).to include([%i[a d], %i[c b]])
        expect(swaps).to include([%i[b c], %i[d a]])
        expect(swaps).to include([%i[a c], %i[d b]])
        expect(swaps).to include([%i[b d], %i[c a]])
      end
    end
  end
end