diff --git a/test/mutual_recursion_test.rb b/test/mutual_recursion_test.rb
index eda2344..3b10d44 100644
--- a/test/mutual_recursion_test.rb
+++ b/test/mutual_recursion_test.rb
@@ -8,6 +8,45 @@ require_relative '../lib/mutual_recursion'
 class InventoryTest < Minitest::Test
   include MutualRecursion
 
+  def one(x, y = 0)
+    return terminal_value(y) if x.negative?
+
+    tail_call { two(x, y + 1) }
+  end
+
+  def two(x, y)
+    tail_call { one(x - 1, y) }
+  end
+
+  def direct(x, y = 0)
+    return terminal_value(y) if x.negative?
+
+    tail_call { direct(x - 1, y + 1) }
+  end
+
+  def lambda_returning
+    terminal_value(-> { 24 })
+  end
+
+  def proc_returning(x, y = 0)
+    return terminal_value(proc { "|#{y}|" }) if x.negative?
+
+    tail_call { proc_returning(x - 1, y + 1) }
+  end
+
+  def bad_return
+    tail_call do
+      Class.new do
+        attr_reader :value, :block
+
+        def initialize
+          @value = 99
+          @block = proc { 25 }
+        end
+      end.new
+    end
+  end
+
   def test_terminal_value
     tail = terminal_value(42)
     assert_equal(42, tail.invoke)
@@ -53,42 +92,3 @@ class InventoryTest < Minitest::Test
     assert_equal(42, tail.invoke)
   end
 end
-
-def one(x, y = 0)
-  return terminal_value(y) if x.negative?
-
-  tail_call { two(x, y + 1) }
-end
-
-def two(x, y)
-  tail_call { one(x - 1, y) }
-end
-
-def direct(x, y = 0)
-  return terminal_value(y) if x.negative?
-
-  tail_call { direct(x - 1, y + 1) }
-end
-
-def lambda_returning
-  terminal_value(-> { 24 })
-end
-
-def proc_returning(x, y = 0)
-  return terminal_value(proc { "|#{y}|" }) if x.negative?
-
-  tail_call { proc_returning(x - 1, y + 1) }
-end
-
-def bad_return
-  tail_call do
-    Class.new do
-      attr_reader :value, :block
-
-      def initialize
-        @value = 99
-        @block = proc { 25 }
-      end
-    end.new
-  end
-end