Add tests for bubble sort

sorting/bubble_sort.rb

@@ -15,8 +15,11 @@ def bubble_sort(array)
 
   array
 end
-puts 'Enter a list of numbers separated by space'
 
-list = gets
-bubble_sort(list)
-print list
+if $0 == __FILE__
+  puts 'Enter a list of numbers separated by space'
+
+  list = gets
+  bubble_sort(list)
+  print list
+end

sorting/bubble_sort_test.rb

@@ -0,0 +1,11 @@
+require 'minitest/autorun'
+require_relative './sort_tests'
+require_relative './bubble_sort'
+
+class TestBubbleSort < Minitest::Test
+  include SortTests
+
+  def sort(input)
+    bubble_sort(input)
+  end
+end