fix: Add support for 'name' Key instances to to_legacy_urlsafe (googleapis#420)

Co-authored-by: Carlos de la Guardia <cguardia@yahoo.com>

Author: lantius

google/cloud/ndb/key.py

@@ -759,7 +759,7 @@ def to_legacy_urlsafe(self, location_prefix):
         """
         return google.cloud.datastore.Key(
             self._key.kind,
-            self._key.id,
+            self._key.id or self._key.name,
             namespace=self._key.namespace,
             project=self._key.project,
         ).to_legacy_urlsafe(location_prefix=location_prefix)

tests/unit/test_key.py

@@ -576,6 +576,15 @@ def test_to_legacy_urlsafe():
             == b"agNzfmZyBwsSAWQYeww"
         )
 
+    @staticmethod
+    @pytest.mark.usefixtures("in_context")
+    def test_to_legacy_urlsafe_name():
+        key = key_module.Key("d", "x", app="f")
+        assert (
+            key.to_legacy_urlsafe(location_prefix="s~")
+            == b"agNzfmZyCAsSAWQiAXgM"
+        )
+
     @staticmethod
     @pytest.mark.usefixtures("in_context")
     @mock.patch("google.cloud.ndb._datastore_api")