diff --git a/tests/test_encryption_utils.py b/tests/test_encryption_utils.py
new file mode 100644
index 0000000..6f8cdc4
--- /dev/null
+++ b/tests/test_encryption_utils.py
@@ -0,0 +1,36 @@
+import string
+import pytest
+
+import puzzle_generator.simple_encryption_utils as seu
+
+
+_STRS = [
+    "",
+    "some_str",
+    "other_strstr!?#",
+    string.printable,
+    string.ascii_uppercase,
+    string.whitespace,
+    "ąęćśłń󿟥ĘĆŚŁŃÓŻŹ",
+    "some_msg_with 🔨 and 🛷!",
+    "a🎄b",
+    "🎮🎈🥅🐾",
+    "🏀",
+]
+
+
+@pytest.mark.parametrize("in_str", _STRS)
+@pytest.mark.parametrize("in_pass", _STRS)
+@pytest.mark.parametrize(
+    ("in_encrypt_str", "in_decrypt_str"), [(seu.encrypt_str, seu.decrypt_str)]
+)
+def test_seu(in_str, in_pass, in_encrypt_str, in_decrypt_str):
+    encrypted, reshash = in_encrypt_str(in_str, in_pass)
+    if in_str:
+        assert encrypted != in_str
+    else:
+        assert not encrypted
+    decrypted = in_decrypt_str(encrypted, in_pass, reshash)
+    assert decrypted == in_str
+    if in_str:
+        assert in_decrypt_str(encrypted, in_pass + "?", reshash) is None
diff --git a/tests/test_simple_encryption_utils.py b/tests/test_simple_encryption_utils.py
deleted file mode 100644
index 2a7c0a1..0000000
--- a/tests/test_simple_encryption_utils.py
+++ /dev/null
@@ -1,29 +0,0 @@
-import pytest
-
-import puzzle_generator.simple_encryption_utils as seu
-
-
-@pytest.mark.parametrize(
-    ("in_str", "in_pass"),
-    [
-        ("some_msg", "some_pass"),
-        ("Ą", "other_pass!?#"),
-        ("some_very_very_very_loooong_str", "ę"),
-        ("ŁÓ", ""),
-        ("", "a"),
-        ("", ""),
-        ("some_msg_with 🔨 and 🛷!", "?"),
-        ("other message!@#$?", "a🎄b"),
-        ("🎮🎈🥅🐾", "🏀"),
-    ],
-)
-def test_seu(in_str, in_pass):
-    encrypted, reshash = seu.encrypt_str(in_str, in_pass)
-    if in_str:
-        assert encrypted != in_str
-    else:
-        assert not encrypted
-    decrypted = seu.decrypt_str(encrypted, in_pass, reshash)
-    assert decrypted == in_str
-    if in_str:
-        assert seu.decrypt_str(encrypted, in_pass + "?", reshash) is None