Fix a border case on LocalFileSystem.copy_from_local where the target path is relative

Without this fix the library would try and fail to create a parent directory named ''

Author: Thierry RAMORASOAVINA

khiops/core/internals/filesystems.py

@@ -477,7 +477,7 @@ def remove(self):
 
     def copy_from_local(self, local_path):
         directory = os.path.dirname(self.path)
-        if not os.path.isdir(directory):
+        if len(directory) > 0 and not os.path.isdir(directory):
             os.makedirs(directory)
         shutil.copy(local_path, self.path)
 

tests/test_helper_functions.py

@@ -10,10 +10,12 @@
 import pathlib
 import platform
 import stat
+import tempfile
 import unittest
 
 import pandas as pd
 
+import khiops.core.internals.filesystems as fs
 from khiops.core.dictionary import DictionaryDomain
 from khiops.core.helpers import _build_multi_table_dictionary_domain, visualize_report
 from khiops.sklearn import train_test_split_dataset
@@ -473,3 +475,20 @@ def test_visualize_report_fails_on_file_with_executable_permissions(self):
 7,4,16.66.64.13
 7,4,15.13.69.18
 """.lstrip()
+
+
+class LocalFileSystemTests(unittest.TestCase):
+
+    def setUp(self):
+        self.current_dir = os.getcwd()  # save the current directory
+
+    def test_copy_from_local_for_a_relative_target_path(self):
+        """Test fs.copy_from_local for the specific case where the target file has a relative path"""
+        tmp_file_fd, tmp_file_path = tempfile.mkstemp(prefix='khiops-python-unit-test', dir='/tmp/')
+        os.close(tmp_file_fd)
+        os.chdir('/tmp')  # folder location of the target file
+        fs.copy_from_local('khiops-python-unit-test-target1.txt', tmp_file_path)
+        fs.copy_from_local('./khiops-python-unit-test-target2.txt', tmp_file_path)
+
+    def tearDown(self):
+        os.chdir(self.current_dir)  # restore the current directory