add test_pickle_reconstructor

Author: Joseph Hamman

xarray/tests/test_backends.py

@@ -19,7 +19,8 @@
 from xarray import (
     DataArray, Dataset, backends, open_dataarray, open_dataset, open_mfdataset,
     save_mfdataset)
-from xarray.backends.common import robust_getitem
+from xarray.backends.common import (robust_getitem,
+                                    PickleByReconstructionWrapper)
 from xarray.backends.netCDF4_ import _extract_nc4_variable_encoding
 from xarray.backends.pydap_ import PydapDataStore
 from xarray.core import indexing
@@ -2921,3 +2922,22 @@ def test_dataarray_to_netcdf_no_name_pathlib(self):
 
             with open_dataarray(tmp) as loaded_da:
                 assert_identical(original_da, loaded_da)
+
+
+def test_pickle_reconstructor():
+
+    lines = ['foo bar spam eggs']
+
+    with create_tmp_file() as tmp:
+        with open(tmp, 'w') as f:
+            f.writelines(lines)
+
+        obj = PickleByReconstructionWrapper(open, tmp)
+
+        assert obj.value.readlines() == lines
+
+        p_obj = pickle.dumps(obj)
+        obj.value.close()  # for windows
+        obj2 = pickle.loads(p_obj)
+
+        assert obj2.value.readlines() == lines