From 2dd11bb83dae12cc7e3ed261a3ecf9ac29c60720 Mon Sep 17 00:00:00 2001
From: Manuel Bustillo <bustikiller@bustikiller.com>
Date: Thu, 1 Aug 2024 20:45:01 +0200
Subject: [PATCH] Initial tests for the swap class

---
 app/services/tables/distribution.rb |  1 +
 spec/services/tables/swap_spec.rb   | 33 +++++++++++++++++++++++++++++
 2 files changed, 34 insertions(+)
 create mode 100644 spec/services/tables/swap_spec.rb

diff --git a/app/services/tables/distribution.rb b/app/services/tables/distribution.rb
index d10d73f..42924c2 100644
--- a/app/services/tables/distribution.rb
+++ b/app/services/tables/distribution.rb
@@ -7,6 +7,7 @@ module Tables
     def initialize(min_per_table:, max_per_table:)
       @min_per_table = min_per_table
       @max_per_table = max_per_table
+      @tables = []
     end
 
     def random_distribution(people)
diff --git a/spec/services/tables/swap_spec.rb b/spec/services/tables/swap_spec.rb
new file mode 100644
index 0000000..bd246e2
--- /dev/null
+++ b/spec/services/tables/swap_spec.rb
@@ -0,0 +1,33 @@
+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