diff --git a/test/py/testing.py b/test/py/testing.py
index 366ac78..c4c8017 100644
--- a/test/py/testing.py
+++ b/test/py/testing.py
@@ -16,13 +16,13 @@
 
 ExtensionsOfInterest = ['*.OBK', '*.OLB', '*.DSN', '*.DBK']
 
-def get_files_of_interest(path: str, file_extensions: List[str]) -> List[str]:
+def get_files_of_interest(path: Path, file_extensions: List[str]) -> List[Path]:
     """
     Get a list of absolute paths to files with specified extension.
     This function searches recursively through the path.
 
     Usage e.g.
-        >>> files = get_files_of_interest('/home/some_dir', ['*.txt', '*.log'])
+        >>> files = get_files_of_interest(Path('/home/some_dir'), ['*.txt', '*.log'])
         >>> print(files)
         >>> ['/home/som_dir/sub_dir/foo.txt', '/home/some_dir/bar.log']
     """
@@ -30,21 +30,19 @@ def get_files_of_interest(path: str, file_extensions: List[str]) -> List[str]:
     files = []
 
     for extension in file_extensions:
-        for file in Path(path).rglob(extension):
+        for file in path.rglob(extension):
             files += [file]
 
     return files
 
-def add_new_repo_to_database(db: FileErrorDatabase, url: str, base_path: str) -> None:
+def add_new_repo_to_database(db: FileErrorDatabase, url: str, base_path: Path) -> None:
 
     author  = url.split('.git')[0].split('/')[-2]
     project = url.split('.git')[0].split('/')[-1]
 
-    base_path = os.path.join(base_path, author, project)
+    base_path = base_path / author / project
 
-    exists_on_fs = os.path.exists(base_path)
-
-    if exists_on_fs:
+    if base_path.exists():
         print(f'Repository {base_path} does already exist, do not clone.')
         fs_repo = Repo(base_path)
     else:
@@ -60,7 +58,7 @@ def add_new_repo_to_database(db: FileErrorDatabase, url: str, base_path: str) ->
     files = get_files_of_interest(base_path, ExtensionsOfInterest)
 
     for file in files:
-        file = os.path.join('.', os.path.relpath(file, base_path))
+        file = Path(os.path.join('.', os.path.relpath(file, base_path)))
         repo_file = RepoFile(path=file, errors=99999)
 
         if not db.isFileInRepo(repo, repo_file):
@@ -68,8 +66,8 @@ def add_new_repo_to_database(db: FileErrorDatabase, url: str, base_path: str) ->
 
     db.addRepo(repo)
 
-def write_back_err_count(db: FileErrorDatabase, path_err_cnt_log: str, path_thirdparty_designs: str) -> None:
-    with open(path_err_cnt_log, 'r') as f:
+def write_back_err_count(db: FileErrorDatabase, path_err_cnt_log: Path, path_thirdparty_designs: Path) -> None:
+    with path_err_cnt_log.open() as f:
         log = f.readlines()
 
     for line in log:
@@ -81,14 +79,14 @@ def write_back_err_count(db: FileErrorDatabase, path_err_cnt_log: str, path_thir
         expect_err = int(matches[1])
         file_path  = str(matches[2])
 
-        author  = file_path[len(path_thirdparty_designs):].split(os.path.sep)[1]
-        project = file_path[len(path_thirdparty_designs):].split(os.path.sep)[2]
+        author  = file_path[len(str(path_thirdparty_designs)):].split(os.path.sep)[1]
+        project = file_path[len(str(path_thirdparty_designs)):].split(os.path.sep)[2]
 
-        path_repo = os.path.join(path_thirdparty_designs, author, project)
+        path_repo = path_thirdparty_designs / author / project
 
         # Make path relative
         file_path = os.path.relpath(file_path, path_repo)
-        file_path = os.path.join('.', file_path)
+        file_path = Path(os.path.join('.', file_path))
 
         repo = db.getRepoByNames(author, project)
         file = db.getFileByPath(repo, file_path)
@@ -96,8 +94,8 @@ def write_back_err_count(db: FileErrorDatabase, path_err_cnt_log: str, path_thir
         db.updateErrorCounter(file, actual_err)
 
 
-def create_repo_cpp_unit_test(repo: Repository, path_repo: str, path_unit_test: str) -> None:
-    with open(path_unit_test, 'w') as f:
+def create_repo_cpp_unit_test(repo: Repository, path_repo: Path, path_unit_test: Path) -> None:
+    with path_unit_test.open('w', encoding='utf-8') as f:
         preamble = """// THIS FILE IS AUTOMATICALLY GENERATED! DO NOT MODIFY IT!
 
 
@@ -198,8 +196,8 @@ def create_repo_cpp_unit_test(repo: Repository, path_repo: str, path_unit_test:
     do_write_back = args.write_back
     do_download = args.do_download
 
-    path_thirdparty_designs = args.path_thirdparty_designs
-    path_unit_tests         = args.path_unit_tests
+    path_thirdparty_designs = Path(args.path_thirdparty_designs)
+    path_unit_tests         = Path(args.path_unit_tests)
     path_err_cnt_log        = args.path_err_cnt_log
 
     path_db = args.path_db
@@ -207,10 +205,10 @@ def create_repo_cpp_unit_test(repo: Repository, path_repo: str, path_unit_test:
     if not do_generate_unit_tests and not do_write_back and not do_download:
         parser.print_help()
 
-    def generate_unit_tests(db: FileErrorDatabase, path_thirdparty_designs: str, path_unit_tests: str) -> None:
+    def generate_unit_tests(db: FileErrorDatabase, path_thirdparty_designs: Path, path_unit_tests: Path) -> None:
         for repo in db.data.repositories:
-            path_repo      = os.path.join(path_thirdparty_designs, repo.author, repo.project)
-            path_unit_test = os.path.join(path_unit_tests, f'Test_{repo.author}_{repo.project}.cpp')
+            path_repo      = path_thirdparty_designs / repo.author / repo.project
+            path_unit_test = path_unit_tests / f'Test_{repo.author}_{repo.project}.cpp'
 
             create_repo_cpp_unit_test(repo, path_repo, path_unit_test)