fixes to get tests passing on windows

Author: alimanfoo

zarr/storage.py

@@ -194,6 +194,9 @@ def __getitem__(self, key):
     def __setitem__(self, key, value):
         # accept any value that can be written to a file
 
+        # destination path for key
+        dest_path = os.path.join(self.path, key)
+
         # write to temporary file
         with tempfile.NamedTemporaryFile(mode='wb', delete=False,
                                          dir=self.path,
@@ -203,7 +206,9 @@ def __setitem__(self, key, value):
             temp_path = f.name
 
         # move temporary file into place
-        os.rename(temp_path, os.path.join(self.path, key))
+        if os.path.exists(dest_path):
+            os.remove(dest_path)
+        os.rename(temp_path, dest_path)
 
     def __delitem__(self, key):
 

zarr/tests/test_core.py

@@ -46,16 +46,13 @@ def test_nbytes_stored():
     eq(sum(len(v) for v in store.values()), z.nbytes_stored)
 
     # custom store, doesn't support size determination
-    with NamedTemporaryFile() as f:
-        store = zict.Zip(f.name, mode='w')
-        # N.B., use zlib for now as blosc extension currently not compatible
-        # with zict,Zip
-        init_store(store, shape=1000, chunks=100, compression='zlib',
-                   compression_opts=1)
-        z = Array(store)
-        eq(-1, z.nbytes_stored)
-        z[:] = 42
-        eq(-1, z.nbytes_stored)
+    store = zict.Zip('test.zip', mode='w')
+    init_store(store, shape=1000, chunks=100, compression='zlib',
+               compression_opts=1)
+    z = Array(store)
+    eq(-1, z.nbytes_stored)
+    z[:] = 42
+    eq(-1, z.nbytes_stored)
 
 
 class TestArray(unittest.TestCase):