Wrap unreadable APIResponse mapping keys

Co-authored-by: Shri Sukhani <shrisukhani@users.noreply.github.com>

Author: cursoragent

hyperbrowser/transport/base.py

@@ -28,7 +28,17 @@ def from_json(
                 f"Failed to parse response data for {model_name}: "
                 f"expected a mapping but received {actual_type_name}"
             )
-        for key in json_data.keys():
+        try:
+            response_keys = list(json_data.keys())
+        except HyperbrowserError:
+            raise
+        except Exception as exc:
+            raise HyperbrowserError(
+                f"Failed to parse response data for {model_name}: "
+                "unable to read mapping keys",
+                original_error=exc,
+            ) from exc
+        for key in response_keys:
             if isinstance(key, str):
                 continue
             key_type_name = type(key).__name__

tests/test_transport_base.py

@@ -1,3 +1,4 @@
+from collections.abc import Mapping
 from typing import cast
 
 import pytest
@@ -18,6 +19,18 @@ def __init__(self, **kwargs):
         raise HyperbrowserError("model validation failed")
 
 
+class _BrokenKeysMapping(Mapping[str, object]):
+    def __iter__(self):
+        raise RuntimeError("cannot iterate mapping keys")
+
+    def __len__(self) -> int:
+        return 1
+
+    def __getitem__(self, key: str) -> object:
+        _ = key
+        return "value"
+
+
 def test_api_response_from_json_parses_model_data() -> None:
     response = APIResponse.from_json(
         {"name": "job-1", "retries": 2}, _SampleResponseModel
@@ -67,6 +80,19 @@ def test_api_response_from_json_wraps_non_hyperbrowser_errors() -> None:
     assert exc_info.value.original_error is not None
 
 
+def test_api_response_from_json_wraps_unreadable_mapping_keys() -> None:
+    with pytest.raises(
+        HyperbrowserError,
+        match=(
+            "Failed to parse response data for _SampleResponseModel: "
+            "unable to read mapping keys"
+        ),
+    ) as exc_info:
+        APIResponse.from_json(_BrokenKeysMapping(), _SampleResponseModel)
+
+    assert exc_info.value.original_error is not None
+
+
 def test_api_response_from_json_preserves_hyperbrowser_errors() -> None:
     with pytest.raises(HyperbrowserError, match="model validation failed") as exc_info:
         APIResponse.from_json({}, _RaisesHyperbrowserModel)