fixups to get api tests passing and add context

api/src/opentrons/protocol_runner/legacy_command_mapper.py

@@ -3,7 +3,6 @@
 from collections import defaultdict
 from datetime import datetime
 from typing import Dict, List, Optional, Tuple, Union
-from traceback import format_exception, format_exception_only
 
 from opentrons_shared_data.pipette.dev_types import PipetteNameType
 from opentrons.types import MountType, DeckSlotName, Location
@@ -60,7 +59,7 @@ def __init__(self, wrapping_exc: BaseException) -> None:
             super().__init__(
                 code=ErrorCodes.GENERAL_ERROR,
                 message=str(wrapping_exc),
-                wrapping=[PythonException(wrapping_exc)]
+                wrapping=[PythonException(wrapping_exc)],
             )
 
 

api/src/opentrons/protocols/execution/errors.py

@@ -1,4 +1,5 @@
-from opentrons_shared_data.errors.exceptions import GeneralError, PythonException
+from opentrons_shared_data.errors.exceptions import GeneralError
+
 
 class ExceptionInProtocolError(GeneralError):
     """This exception wraps an exception that was raised from a protocol
@@ -17,7 +18,8 @@ def __init__(self, original_exc, original_tb, message, line):
                 self.original_exc.__class__.__name__,
                 " [line {}]".format(self.line) if self.line else "",
                 self.message,
-            ))
+            ),
+        )
 
     def __str__(self):
         return self.message

api/tests/opentrons/protocol_engine/state/test_command_store.py

@@ -830,29 +830,17 @@ def test_command_store_saves_unknown_finish_error() -> None:
                 # and they wrap
                 wrappedErrors=[
                     errors.ErrorOccurrence(
-                        # the wrapped error(s) have the same id and creation time
                         id="error-id",
                         createdAt=datetime(year=2021, month=1, day=1),
-                        # but the details of the wrapped exception
-                        errorType="GeneralError",
-                        detail="Error 4000 GENERAL_ERROR (GeneralError)",
+                        errorType="PythonException",
+                        detail="RuntimeError: oh no\n",
                         errorCode="4000",
-                        # including further wrapped errors
-                        wrappedErrors=[
-                            errors.ErrorOccurrence(
-                                id="error-id",
-                                createdAt=datetime(year=2021, month=1, day=1),
-                                errorType="PythonException",
-                                detail="RuntimeError: oh no\n",
-                                errorCode="4000",
-                                # and we get some fun extra info if this wraps a normal exception
-                                errorInfo={
-                                    "class": "RuntimeError",
-                                    "args": "('oh no',)",
-                                },
-                                wrappedErrors=[],
-                            )
-                        ],
+                        # and we get some fun extra info if this wraps a normal exception
+                        errorInfo={
+                            "class": "RuntimeError",
+                            "args": "('oh no',)",
+                        },
+                        wrappedErrors=[],
                     )
                 ],
             )

shared-data/python/opentrons_shared_data/errors/__init__.py

@@ -9,7 +9,13 @@
 
 from .categories import ErrorCategories, ErrorCategory
 from .codes import ErrorCodes, ErrorCode
-from .exceptions import EnumeratedError, PythonException, GeneralError, RoboticsControlError, RoboticsInteractionError
+from .exceptions import (
+    EnumeratedError,
+    PythonException,
+    GeneralError,
+    RoboticsControlError,
+    RoboticsInteractionError,
+)
 
 __all__ = [
     "ErrorCategory",
@@ -20,5 +26,5 @@
     "PythonException",
     "GeneralError",
     "RoboticsControlError",
-    "RoboticsInteractionError"
+    "RoboticsInteractionError",
 ]

shared-data/python/opentrons_shared_data/errors/exceptions.py

@@ -174,10 +174,12 @@ def __init__(self, exc: BaseException) -> None:
         """Build a PythonException."""
 
         def _descend_exc_ctx(exc: BaseException) -> List[PythonException]:
+            descendants: List[PythonException] = []
+            if exc.__context__:
+                descendants.append(PythonException(exc.__context__))
             if exc.__cause__:
-                return [PythonException(exc.__cause__)]
-            else:
-                return []
+                descendants.append(PythonException(exc.__cause__))
+            return descendants
 
         base_details = {
             k: str(v)

shared-data/python/tests/errors/test_exceptions.py

@@ -41,7 +41,7 @@ def _raise_inner() -> None:
 
 
 def test_exception_wrapping_rethrow() -> None:
-    """We can even wrap exceptions inside an except."""
+    """We can wrap raise-froms."""
     try:
         try:
             raise RuntimeError("oh no!")
@@ -53,3 +53,22 @@ def test_exception_wrapping_rethrow() -> None:
     assert wrapped.detail["class"] == "RuntimeError"
     assert wrapped.detail["traceback"]
     assert wrapped.detail["args"] == "('oh no!',)"
+
+
+def test_exception_wrapping_error_in_except() -> None:
+    """We can even wrap exceptions in exception handlers."""
+    try:
+        try:
+            raise RuntimeError("oh no!")
+        except RuntimeError:
+            raise KeyError("uh oh")
+    except BaseException as e:
+        wrapped = PythonException(e)
+
+    # when we have an exception-during-handler, the originally-handled
+    # exception is what's bubbled up:
+    assert wrapped.detail["class"] == "KeyError"
+    assert len(wrapped.wrapping) == 1
+    assert wrapped.wrapping[0].detail["class"] == "RuntimeError"
+    assert wrapped.wrapping[0].detail["traceback"]
+    assert wrapped.wrapping[0].detail["args"] == "('oh no!',)"