WIP specs

spec/services/tables/shift_spec.rb

@@ -2,5 +2,32 @@ require 'rails_helper'
 
 module Tables
   RSpec.describe Shift do
+    describe '#each' do
+      let(:shifts) do
+        acc = []
+        described_class.new(initial_solution).each do |solution|
+          acc << solution.tables.map(&:dup)
+        end
+        acc
+      end
+
+      context 'when there are two tables with two people each' do
+        let(:initial_solution) do
+          Distribution.new(min_per_table: 2, max_per_table: 2).tap do |distribution|
+            distribution.tables << %i[a b].to_table
+            distribution.tables << %i[c d].to_table
+          end
+        end
+
+        it 'yields all possible shifts between the tables' do
+          expect(shifts).to contain_exactly(
+            [[:b], %i[c d a]],
+            [[:a], %i[c d b]],
+            [%i[b a d], [:c]],
+            [%i[b a c], [:d]]
+          )
+        end
+      end
+    end
   end
 end