def _check_raise_missing_from(self, node: astroid.Raise) -> None:
if node.exc is None:
# This is a plain `raise`, raising the previously-caught exception. No need for a
# cause.
return
# We'd like to check whether we're inside an `except` clause:
containing_except_node = utils.find_except_wrapper_node_in_scope(node)
if not containing_except_node:
return
# We found a surrounding `except`! We're almost done proving there's a
# `raise-missing-from` here. The only thing we need to protect against is that maybe
# the `raise` is raising the exception that was caught, possibly with some shenanigans
# like `exc.with_traceback(whatever)`. We won't analyze these, we'll just assume
# there's a violation on two simple cases: `raise SomeException(whatever)` and `raise
# SomeException`.
if containing_except_node.name is None:
# The `except` doesn't have an `as exception:` part, meaning there's no way that
# the `raise` is raising the same exception.
self.add_message("raise-missing-from", node=node)
elif isinstance(node.exc, astroid.Call) and isinstance(
node.exc.func, astroid.Name):
# We have a `raise SomeException(whatever)`.
self.add_message("raise-missing-from", node=node)
elif (isinstance(node.exc, astroid.Name)
and node.exc.name != containing_except_node.name.name):
# We have a `raise SomeException`.
self.add_message("raise-missing-from", node=node)
def _check_raise_missing_from(self, node: nodes.Raise) -> None:
if node.exc is None:
# This is a plain `raise`, raising the previously-caught exception. No need for a
# cause.
return
# We'd like to check whether we're inside an `except` clause:
containing_except_node = utils.find_except_wrapper_node_in_scope(node)
if not containing_except_node:
return
# We found a surrounding `except`! We're almost done proving there's a
# `raise-missing-from` here. The only thing we need to protect against is that maybe
# the `raise` is raising the exception that was caught, possibly with some shenanigans
# like `exc.with_traceback(whatever)`. We won't analyze these, we'll just assume
# there's a violation on two simple cases: `raise SomeException(whatever)` and `raise
# SomeException`.
if containing_except_node.name is None:
# The `except` doesn't have an `as exception:` part, meaning there's no way that
# the `raise` is raising the same exception.
class_of_old_error = "Exception"
if isinstance(containing_except_node.type,
(nodes.Name, nodes.Tuple)):
# 'except ZeroDivisionError' or 'except (ZeroDivisionError, ValueError)'
class_of_old_error = containing_except_node.type.as_string()
self.add_message(
"raise-missing-from",
node=node,
args=(
f"'except {class_of_old_error} as exc' and ",
node.as_string(),
"exc",
),
confidence=HIGH,
)
elif (isinstance(node.exc, nodes.Call)
and isinstance(node.exc.func, nodes.Name)
or isinstance(node.exc, nodes.Name)
and node.exc.name != containing_except_node.name.name):
# We have a `raise SomeException(whatever)` or a `raise SomeException`
self.add_message(
"raise-missing-from",
node=node,
args=("", node.as_string(), containing_except_node.name.name),
confidence=HIGH,
)