[Fix]: fix missing check of directory in scandir (#1110)

* Missing check for dir in the 'else' clause

Fixing issue when recursively scanning directories with filenames starting with '.'  Without this fix, the `if not entry.name.startswith('.') and entry.is_file()` logic falls through to the `else` clause which in the current code base will error out as it encounters '.' files (e.g. .DS_Store)

* Updated code per comments

* fixing indentation

* fix indenterror and add comment

* remove .DS_Store and add .file
Co-authored-by: zhouzaida <zhouzaida@163.com>

mmcv/utils/path.py

@@ -63,16 +63,12 @@ def scandir(dir_path, suffix=None, recursive=False):
         for entry in os.scandir(dir_path):
             if not entry.name.startswith('.') and entry.is_file():
                 rel_path = osp.relpath(entry.path, root)
-                if suffix is None:
+                if suffix is None or rel_path.endswith(suffix):
                     yield rel_path
-                elif rel_path.endswith(suffix):
-                    yield rel_path
-            else:
-                if recursive:
-                    yield from _scandir(
-                        entry.path, suffix=suffix, recursive=recursive)
-                else:
-                    continue
+            elif recursive and os.path.isdir(entry.path):
+                # scan recursively if entry.path is a directory
+                yield from _scandir(
+                    entry.path, suffix=suffix, recursive=recursive)
 
     return _scandir(dir_path, suffix=suffix, recursive=recursive)
 

tests/test_utils/test_path.py

@@ -40,12 +40,13 @@ def test_scandir():
 
     filenames_recursive = [
         'a.bin', '1.txt', '2.txt', '1.json', '2.json', 'sub/1.json',
-        'sub/1.txt'
+        'sub/1.txt', '.file'
     ]
-    assert set(mmcv.scandir(folder,
-                            recursive=True)) == set(filenames_recursive)
-    assert set(mmcv.scandir(Path(folder),
-                            recursive=True)) == set(filenames_recursive)
+    # .file starts with '.' and is a file so it will not be scanned
+    assert set(mmcv.scandir(folder, recursive=True)) == set(
+        [filename for filename in filenames_recursive if filename != '.file'])
+    assert set(mmcv.scandir(Path(folder), recursive=True)) == set(
+        [filename for filename in filenames_recursive if filename != '.file'])
     assert set(mmcv.scandir(folder, '.txt', recursive=True)) == set([
         filename for filename in filenames_recursive
         if filename.endswith('.txt')