diff --git a/tests/y_2015/test_2015_day4.py b/tests/y_2015/test_2015_day4.py
index 7e24792..ff8bcf6 100644
--- a/tests/y_2015/test_2015_day4.py
+++ b/tests/y_2015/test_2015_day4.py
@@ -1,6 +1,6 @@
 from __future__ import annotations
 
-from unittest.mock import mock_open, patch
+from unittest.mock import mock_open, patch, MagicMock
 
 from y_2015.day4 import Day
 
@@ -8,11 +8,31 @@
     day = Day()
 
 
-def test_calculate_1():
+def test_hash_logic():
     day._input_data = [["abcdef"]]
     day._preprocess_input()
-    assert day._calculate_1() == 609043
+    assert day.hash_logic(5) == 609043
 
     day._input_data = [["pqrstuv"]]
     day._preprocess_input()
-    assert day._calculate_1() == 1048970
+    assert day.hash_logic(5) == 1048970
+
+    day._input_data = [["abcdef"]]
+    day._preprocess_input()
+    assert day.hash_logic(1) == 31
+
+    day._input_data = [["abcdef"]]
+    day._preprocess_input()
+    assert day.hash_logic(2) == 298
+
+
+def test_calculate_1():
+    day.hash_logic = MagicMock()
+    day._calculate_1()
+    day.hash_logic.assert_called_once_with(5)
+
+
+def test_calculate_2():
+    day.hash_logic = MagicMock()
+    day._calculate_2()
+    day.hash_logic.assert_called_once_with(6)