Mixifying

test/test_helper.exs

@@ -0,0 +1 @@
+ExUnit.start()

test/year_2025/dial_test.exs

@@ -0,0 +1,25 @@
+defmodule AdventOfCode.Year2025.DialTest do
+  use ExUnit.Case, async: true
+
+  import AdventOfCode.Year2025.Dial
+
+  test "dial starts at 50" do
+    { index, _ } = rotate([])
+    assert index == 50
+  end
+
+  test "rotate right increments index" do
+    {index, _} = rotate(["R1"])
+    assert index == 51
+  end
+
+  test "rotate left decrements index" do
+    {index, _} = rotate(["L1"])
+    assert index ==49 
+  end
+
+  test "increments zero crossings when landing on zero" do
+    {_, zeroes} = rotate(["R50"])
+    assert zeroes == 1
+  end
+end