diff --git a/tests/test_common.py b/tests/test_common.py
index 51d379c..fc0a237 100644
--- a/tests/test_common.py
+++ b/tests/test_common.py
@@ -1,9 +1,7 @@
 import unittest
-from unittest.mock import patch, mock_open, MagicMock
-from pathlib import Path
-import logging
+from unittest.mock import patch
+from pyfakefs.fake_filesystem_unittest import TestCase
 
-# Assuming the function path2bytes is in a module named common
 from gnssanalysis.gn_io.common import path2bytes
 
 
@@ -34,19 +32,25 @@ def test_bytes_input(self):
         result = path2bytes(b"test data")
         self.assertEqual(result, b"test data")
 
-    @patch("gnssanalysis.gn_io.common._logging.error")
-    def test_file_not_found(self, mock_logging_error):
-        with patch("gnssanalysis.gn_io.common._txt2bytes", side_effect=FileNotFoundError):
-            print("testing path")
-            result = path2bytes("nonexistent.txt")
-            self.assertIsNone(result)
-            mock_logging_error.assert_called_once_with("File nonexistent.txt not found. Returning empty bytes.")
-
-    @patch("gnssanalysis.gn_io.common._logging.error")
-    def test_generic_exception(self, mock_logging_error):
-        with patch("gnssanalysis.gn_io.common._txt2bytes", side_effect=Exception("Generic error")):
-            result = path2bytes("test.txt")
-            self.assertIsNone(result)
-            mock_logging_error.assert_called_once_with(
-                "Error reading file test.txt with error Generic error. Returning empty bytes."
-            )
+
+class TestPath2BytesWithFakeFs(TestCase):
+    def setUp(self):
+        self.setUpPyfakefs()
+
+    def test_file_not_found_and_file_read(self):
+        # Create a file, but not the one we're looking for
+        self.fs.create_file("testfile.txt", contents=b"hello")
+        with self.assertRaises(FileNotFoundError):
+            path2bytes("nonexistent.txt")
+
+        # Now open the file that does exist and check the contents
+        self.assertEqual(path2bytes("testfile.txt"), b"hello")
+
+    def test_invalid_archive_expand_exception(self):
+        # Test that trying to unpack an archive file which isn't valid archive data, raises an exception
+        self.fs.create_file("invalidarchive.gz", contents=b"hello")
+        self.fs.create_file("invalidarchive.Z", contents=b"hello")
+        with self.assertRaises(Exception):
+            path2bytes("invalidarchive.gz")
+        with self.assertRaises(Exception):
+            path2bytes("invalidarchive.Z")