Ignore None dim_separators in save_array (fix #831) (#832)

* Ignore None dim_separators in save_array (fix #831)

If a store does not have a `dimension_separator` set,
then requesting a non-`None` value should not be an
error.

* Fix flake8

Author: joshmoore

zarr/creation.py

@@ -126,11 +126,12 @@ def create(shape, chunks=True, dtype=None, compressor='default',
     if dimension_separator is None:
         dimension_separator = getattr(store, "_dimension_separator", None)
     else:
-        if getattr(store, "_dimension_separator", None) != dimension_separator:
+        store_separator = getattr(store, "_dimension_separator", None)
+        if store_separator not in (None, dimension_separator):
             raise ValueError(
                 f"Specified dimension_separtor: {dimension_separator}"
                 f"conflicts with store's separator: "
-                f"{store._dimension_separator}")
+                f"{store_separator}")
     dimension_separator = normalize_dimension_separator(dimension_separator)
 
     # initialize array metadata

zarr/tests/test_convenience.py

@@ -18,6 +18,7 @@
     open_consolidated,
     save,
     save_group,
+    save_array,
     copy_all,
 )
 from zarr.core import Array
@@ -225,6 +226,17 @@ def test_consolidated_with_chunk_store():
                       chunk_store=chunk_store)
 
 
+@pytest.mark.parametrize("options", (
+    {"dimension_separator": "/"},
+    {"dimension_separator": "."},
+    {"dimension_separator": None},
+))
+def test_save_array_separator(tmpdir, options):
+    data = np.arange(6).reshape((3, 2))
+    url = tmpdir.join("test.zarr")
+    save_array(url, data, **options)
+
+
 class TestCopyStore(unittest.TestCase):
 
     def setUp(self):