use OS-independent separators

fix tests on Windows

python/tests/test_Result.py

@@ -63,7 +63,7 @@ def h5py_dataset_iterator():
     """Iterate over all datasets in an HDF5 file."""
     def _h5py_dataset_iterator(g, prefix=''):
         for key,item in g.items():
-            path = os.path.join(prefix, key)
+            path = '/'.join([prefix, key])
             if isinstance(item, h5py.Dataset): # test for dataset
                 yield (path, item)
             elif isinstance(item, h5py.Group): # test for group (go down)
@@ -472,7 +472,7 @@ class TestResult:
                     c = [_.decode() for _ in cur[path]]
                     r = ['Unknown Phase Type'] + result.phases
                     assert c == r
-                grp = os.path.split(path)[0]
+                grp = str(path).rpartition('/')[0]
                 for attr in ref[grp].attrs:
                     assert np.array_equal(ref[grp].attrs[attr],cur[grp].attrs[attr])
                 for attr in dset.attrs: