Support overwriting an existing directory

src/hdmf_zarr/backend.py

@@ -1,6 +1,7 @@
 """Module with the Zarr-based I/O-backend for HDMF"""
 # Python imports
 import os
+import shutil
 import warnings
 import numpy as np
 import tempfile
@@ -183,8 +184,11 @@ def open(self):
             # Allow overwriting an exist file (e.g., and HDF5 file). Zarr will normally fail if the
             # existing object at the path is a file. So if we are in `w` mode we need to delete the file first
             if self.mode == 'w' and self.__force_overwrite:
-                if isinstance(self.path, (str, Path)) and os.path.exists(self.path) and os.path.isfile(self.path):
-                    os.remove(self.path)
+                if isinstance(self.path, (str, Path)) and os.path.exists(self.path):
+                    if os.path.isdir(self.path): # directory
+                        shutil.rmtree(self.path)
+                    else:  # File
+                        os.remove(self.path)
 
             # Within zarr, open_consolidated only allows the mode to be 'r' or 'r+'.
             # As a result, when in other modes, the file will not use consolidated metadata.

tests/unit/test_zarrio.py

@@ -211,6 +211,16 @@ def test_force_overwrite_when_file_exists(self):
         # test text file to force overwriting the exsiting file.
         self.create_zarr(force_overwrite=True, mode='w')
 
+    def test_force_overwrite_when_dir_exists(self):
+        """
+        Test that we can overwrite a directory when opening with `w` mode even if there is
+        an existing directory.
+        """
+        # create a Zarr file
+        self.create_zarr()
+        # try to overwrite the existing Zarr file
+        self.create_zarr(force_overwrite=True, mode='w')
+
 
 class TestDimensionLabels(BuildDatasetShapeMixin):
     """