From 1a34c7826193281b74151b6f2024498bbab8d421 Mon Sep 17 00:00:00 2001
From: Peter Bieringer <pb@bieringer.de>
Date: Sat, 18 Apr 2026 16:21:41 +0200
Subject: [PATCH] test and display features of used collection base directory

---
 radicale/pathutils.py                        | 75 +++++++++++++++++++-
 radicale/storage/multifilesystem/__init__.py |  3 +
 2 files changed, 77 insertions(+), 1 deletion(-)

diff --git a/radicale/pathutils.py b/radicale/pathutils.py
index 36a66461..71ba4438 100644
--- a/radicale/pathutils.py
+++ b/radicale/pathutils.py
@@ -407,7 +407,7 @@ def path_supports_symlink(path):
 
 
 def path_is_collision_free_case_sensitive(path):
-    # Test: case sensitive
+    """Check whether path supports case sensitive entries."""
     if not os.path.isdir(path):
         raise ValueError("%r is not a path" % (path))
     base_dir = tempfile.mkdtemp(dir=path)
@@ -452,3 +452,76 @@ def path_is_collision_free_no_short_filename(path):
     os.rmdir(base_dir)
     logger.debug("path_is_collision_free (no short-filename): path=%r result=%s", path, result)
     return result
+
+
+def path_supports_unicode(path):
+    """Check whether path supports unicode."""
+    if not os.path.isdir(path):
+        raise ValueError("%r is not a path" % (path))
+    base_dir = tempfile.mkdtemp(dir=path)
+    part = "TEST😀"
+    test_dir = os.path.join(base_dir, part)
+    result = True
+    try:
+        os.mkdir(test_dir)
+    except OSError:
+        result = False
+    else:
+        with os.scandir(base_dir) as entries:
+            if part not in (e.name for e in entries):
+                result = False
+        # cleanup
+        os.rmdir(test_dir)
+    # cleanup
+    os.rmdir(base_dir)
+    logger.debug("path_supports_unicode: path=%r result=%s", path, result)
+    return result
+
+
+def path_supports_trailing_whitespace(path):
+    """Check whether path supports trailing whitespace."""
+    if not os.path.isdir(path):
+        raise ValueError("%r is not a path" % (path))
+    base_dir = tempfile.mkdtemp(dir=path)
+    part = "TEST "
+    test_dir = os.path.join(base_dir, part)
+    result = True
+    try:
+        os.mkdir(test_dir)
+    except OSError:
+        result = False
+    else:
+        with os.scandir(base_dir) as entries:
+            if part not in (e.name for e in entries):
+                result = False
+        # cleanup
+        os.rmdir(test_dir)
+    # cleanup
+    os.rmdir(base_dir)
+    logger.debug("path_supports_trailing_whitespace: path=%r result=%s", path, result)
+    return result
+
+
+def path_supports_problematic_chars(path):
+    """Check whether path supports problematic chars."""
+    if not os.path.isdir(path):
+        raise ValueError("%r is not a path" % (path))
+    base_dir = tempfile.mkdtemp(dir=path)
+    result = True
+    for char in ['*', '?']:
+        part = "TES" + char + "T"
+        test_dir = os.path.join(base_dir, part)
+        try:
+            os.mkdir(test_dir)
+        except OSError:
+            result = False
+        else:
+            with os.scandir(base_dir) as entries:
+                if part not in (e.name for e in entries):
+                    result = False
+            # cleanup
+            os.rmdir(test_dir)
+    # cleanup
+    os.rmdir(base_dir)
+    logger.debug("path_supports_problematic chars: path=%r result=%s", path, result)
+    return result
diff --git a/radicale/storage/multifilesystem/__init__.py b/radicale/storage/multifilesystem/__init__.py
index 7e6ead8e..7deeaac7 100644
--- a/radicale/storage/multifilesystem/__init__.py
+++ b/radicale/storage/multifilesystem/__init__.py
@@ -180,6 +180,9 @@ class Storage(
                     self._filesystem_root_folder_is_collision_free,
                     filesystem_root_folder_is_collision_free_case_sensitive,
                     filesystem_root_folder_is_collision_free_no_short_filename)
+        logger.info("Storage location subfolder suppports unicode: %s", pathutils.path_supports_unicode(self._get_collection_root_folder()))
+        logger.info("Storage location subfolder suppports trailing whitespace: %s", pathutils.path_supports_trailing_whitespace(self._get_collection_root_folder()))
+        logger.info("Storage location subfolder suppports problematic chars: %s", pathutils.path_supports_problematic_chars(self._get_collection_root_folder()))
         logger.info("Storage cache subfolder usage for 'item': %s", self._use_cache_subfolder_for_item)
         logger.info("Storage cache subfolder usage for 'history': %s", self._use_cache_subfolder_for_history)
         logger.info("Storage cache subfolder usage for 'sync-token': %s", self._use_cache_subfolder_for_synctoken)