fix(evals): never emit blank mocker error messages (SRE-640375)

packages/uipath/pyproject.toml

@@ -1,6 +1,6 @@
 [project]
 name = "uipath"
-version = "2.14.4"
+version = "2.14.5"
 description = "Python SDK and CLI for UiPath Platform, enabling programmatic interaction with automation services, process management, and deployment tools."
 readme = { file = "README.md", content-type = "text/markdown" }
 requires-python = ">=3.11"

packages/uipath/src/uipath/eval/mocks/_input_mocker.py

@@ -14,7 +14,7 @@
 
 from .._execution_context import eval_set_run_id_context
 from ._mock_context import cache_manager_context
-from ._mocker import UiPathInputMockingError
+from ._mocker import UiPathInputMockingError, format_exception_message
 from ._structured_output import generate_structured_output
 from ._types import (
     InputMockingStrategy,
@@ -155,4 +155,6 @@ async def generate_llm_input(
     except UiPathInputMockingError:
         raise
     except Exception as e:
-        raise UiPathInputMockingError(f"Failed to generate input: {str(e)}") from e
+        raise UiPathInputMockingError(
+            f"Failed to generate input: {format_exception_message(e)}"
+        ) from e

packages/uipath/src/uipath/eval/mocks/_llm_mocker.py

@@ -28,6 +28,7 @@
     T,
     UiPathMockResponseGenerationError,
     UiPathNoMockFoundError,
+    format_exception_message,
 )
 from ._structured_output import generate_structured_output
 from ._types import (
@@ -230,7 +231,9 @@ async def response(
 
                 return result
             except Exception as e:
-                raise UiPathMockResponseGenerationError(str(e)) from e
+                raise UiPathMockResponseGenerationError(
+                    format_exception_message(e)
+                ) from e
         else:
             raise UiPathNoMockFoundError(f"Method '{function_name}' is not simulated.")
 

packages/uipath/src/uipath/eval/mocks/_mocker.py

@@ -22,6 +22,17 @@ async def response(
         raise NotImplementedError()
 
 
+def format_exception_message(e: BaseException) -> str:
+    """Format an exception for wrapped error messages, always naming its type.
+
+    Timeout and cancellation exceptions (``asyncio.TimeoutError``,
+    ``CancelledError``, httpx timeouts) often have an empty ``str``, which
+    otherwise produces blank, undiagnosable error messages downstream.
+    """
+    message = str(e).strip()
+    return f"{type(e).__name__}: {message}" if message else type(e).__name__
+
+
 class UiPathNoMockFoundError(Exception):
     """Exception when a mocker is unable to find a match with the invocation. This is a signal to invoke the real function."""
 

packages/uipath/tests/cli/eval/mocks/test_mock_error_messages.py

@@ -0,0 +1,51 @@
+import asyncio
+from typing import Any
+
+import pytest
+from _pytest.monkeypatch import MonkeyPatch
+
+from uipath.eval.mocks import _input_mocker
+from uipath.eval.mocks._input_mocker import generate_llm_input
+from uipath.eval.mocks._mocker import (
+    UiPathInputMockingError,
+    format_exception_message,
+)
+from uipath.eval.mocks._types import InputMockingStrategy
+
+
+def test_format_exception_message_with_message():
+    assert format_exception_message(ValueError("bad value")) == "ValueError: bad value"
+
+
+def test_format_exception_message_empty_str():
+    # asyncio.TimeoutError and CancelledError stringify to "" — the type name
+    # must still be surfaced so the wrapped message is never blank.
+    assert format_exception_message(asyncio.TimeoutError()) == "TimeoutError"
+    assert format_exception_message(asyncio.CancelledError()) == "CancelledError"
+
+
+def test_format_exception_message_whitespace_only():
+    assert format_exception_message(RuntimeError("   ")) == "RuntimeError"
+
+
+@pytest.mark.asyncio
+async def test_generate_llm_input_wraps_empty_str_exception(
+    monkeypatch: MonkeyPatch,
+):
+    monkeypatch.setenv("UIPATH_URL", "https://example.com")
+    monkeypatch.setenv("UIPATH_ACCESS_TOKEN", "test-token")
+
+    async def raise_timeout(*args: Any, **kwargs: Any) -> Any:
+        raise asyncio.TimeoutError()
+
+    monkeypatch.setattr(_input_mocker, "generate_structured_output", raise_timeout)
+
+    with pytest.raises(UiPathInputMockingError) as exc_info:
+        await generate_llm_input(
+            mocking_strategy=InputMockingStrategy(prompt="generate something"),
+            input_schema={"type": "object", "properties": {}},
+            expected_behavior="",
+            expected_output={},
+        )
+
+    assert str(exc_info.value) == "Failed to generate input: TimeoutError"