Correct default fill_value for creation.create

Author: benjeffery

zarr/creation.py

@@ -16,7 +16,7 @@
 
 
 def create(shape, chunks=True, dtype=None, compressor='default',
-           fill_value=0, order='C', store=None, synchronizer=None,
+           fill_value=None, order='C', store=None, synchronizer=None,
            overwrite=False, path=None, chunk_store=None, filters=None,
            cache_metadata=True, cache_attrs=True, read_only=False,
            object_codec=None, dimension_separator=None,

zarr/tests/test_core.py

@@ -18,6 +18,7 @@
 from pkg_resources import parse_version
 
 from zarr.core import Array
+from zarr.creation import create
 from zarr.meta import json_loads
 from zarr.n5 import N5Store, N5FSStore, n5_keywords
 from zarr.storage import (
@@ -1249,6 +1250,14 @@ def test_object_arrays_vlen_bytes(self):
         assert_array_equal(data, z[:])
         z.store.close()
 
+        # Zero-length bytes
+        z = create(shape=(1,), dtype=bytes)
+        assert z.dtype == object
+        assert isinstance(z.filters[0], VLenBytes)
+        z[0] = b''
+        assert z[0] == b''
+        z.store.close()
+
         z = self.create_array(shape=data.shape, dtype=object, object_codec=Pickle())
         z[:] = data
         assert_array_equal(data, z[:])