diff --git a/tests/y_2022/test_2022_day1.py b/tests/y_2022/test_2022_day1.py
new file mode 100644
index 0000000..6c605da
--- /dev/null
+++ b/tests/y_2022/test_2022_day1.py
@@ -0,0 +1,48 @@
+from __future__ import annotations
+
+from unittest.mock import mock_open, patch
+
+from y_2022.day1 import Day
+
+with patch("builtins.open", mock_open(read_data="0")):
+    day = Day()
+
+
+def test__preprocess_input():
+    day._input_data = []
+    day._preprocess_input()
+    assert day._Day__input_data == []
+
+    day._input_data = [
+        ["1000", "2000", "3000"],
+        ["4000"],
+        ["5000", "6000"],
+        ["7000", "8000", "9000"],
+        ["10000"],
+    ]
+    day._preprocess_input()
+    assert day._Day__input_data == [
+        [1000, 2000, 3000],
+        [4000],
+        [5000, 6000],
+        [7000, 8000, 9000],
+        [10000],
+    ]
+
+
+def test_calculate_1():
+    day._Day__input_data = [
+        [1000, 2000, 3000],
+        [4000],
+    ]
+    assert day._calculate_1() == 6000
+
+
+def test_calculate_2():
+    day._Day__input_data = [
+        [1000, 2000, 3000],
+        [4000],
+        [5000, 6000],
+        [7000, 8000, 9000],
+    ]
+    assert day._calculate_2() == 41000