Use root StacIO in Catalog.set_root

Author: duckontheweb

pystac/catalog.py

@@ -180,11 +180,13 @@ def __repr__(self) -> str:
         return "<Catalog id={}>".format(self.id)
 
     def set_root(self, root: Optional["Catalog"]) -> None:
-        STACObject.set_root(self, root)
+        super().set_root(root)
         if root is not None:
             root._resolved_objects = ResolvedObjectCache.merge(
                 root._resolved_objects, self._resolved_objects
             )
+            if root._stac_io is not None:
+                self._stac_io = root._stac_io
 
     def is_relative(self) -> bool:
         return self.catalog_type in [

tests/test_catalog.py

@@ -18,6 +18,7 @@
     HIERARCHICAL_LINKS,
 )
 from pystac.extensions.label import LabelClasses, LabelExtension, LabelType
+from pystac.stac_io import DefaultStacIO
 from pystac.utils import is_absolute_href, join_path_or_url, JoinType
 from tests.utils import (
     TestCases,
@@ -107,6 +108,19 @@ def test_from_dict_set_root(self) -> None:
         collection = Catalog.from_dict(cat_dict, root=root_cat)
         self.assertIs(collection.get_root(), root_cat)
 
+    def test_from_dict_uses_root_stac_io(self) -> None:
+        class CustomStacIO(DefaultStacIO):
+            pass
+
+        path = TestCases.get_path("data-files/catalogs/test-case-1/catalog.json")
+        with open(path) as f:
+            cat_dict = json.load(f)
+        root_cat = pystac.Catalog(id="test", description="test desc")
+        root_cat._stac_io = CustomStacIO()
+
+        collection = Catalog.from_dict(cat_dict, root=root_cat)
+        self.assertIsInstance(collection._stac_io, CustomStacIO)
+
     def test_read_remote(self) -> None:
         # TODO: Move this URL to the main stac-spec repo once the example JSON is fixed.
         catalog_url = (