pybind11/tests/test_exceptions.py
2023-02-22 06:18:55 -08:00

389 lines
13 KiB
Python

import sys
import pytest
import env
import pybind11_cross_module_tests as cm
import pybind11_tests # noqa: F401
from pybind11_tests import exceptions as m
def test_std_exception(msg):
with pytest.raises(RuntimeError) as excinfo:
m.throw_std_exception()
assert msg(excinfo.value) == "This exception was intentionally thrown."
def test_error_already_set(msg):
with pytest.raises(RuntimeError) as excinfo:
m.throw_already_set(False)
assert (
msg(excinfo.value)
== "Internal error: pybind11::error_already_set called while Python error indicator not set."
)
with pytest.raises(ValueError) as excinfo:
m.throw_already_set(True)
assert msg(excinfo.value) == "foo"
def test_raise_from(msg):
with pytest.raises(ValueError) as excinfo:
m.raise_from()
assert msg(excinfo.value) == "outer"
assert msg(excinfo.value.__cause__) == "inner"
def test_raise_from_already_set(msg):
with pytest.raises(ValueError) as excinfo:
m.raise_from_already_set()
assert msg(excinfo.value) == "outer"
assert msg(excinfo.value.__cause__) == "inner"
def test_cross_module_exceptions(msg):
with pytest.raises(RuntimeError) as excinfo:
cm.raise_runtime_error()
assert str(excinfo.value) == "My runtime error"
with pytest.raises(ValueError) as excinfo:
cm.raise_value_error()
assert str(excinfo.value) == "My value error"
with pytest.raises(ValueError) as excinfo:
cm.throw_pybind_value_error()
assert str(excinfo.value) == "pybind11 value error"
with pytest.raises(TypeError) as excinfo:
cm.throw_pybind_type_error()
assert str(excinfo.value) == "pybind11 type error"
with pytest.raises(StopIteration) as excinfo:
cm.throw_stop_iteration()
with pytest.raises(cm.LocalSimpleException) as excinfo:
cm.throw_local_simple_error()
assert msg(excinfo.value) == "external mod"
with pytest.raises(KeyError) as excinfo:
cm.throw_local_error()
# KeyError is a repr of the key, so it has an extra set of quotes
assert str(excinfo.value) == "'just local'"
# TODO: FIXME
@pytest.mark.xfail(
"env.MACOS and (env.PYPY or pybind11_tests.compiler_info.startswith('Homebrew Clang'))",
raises=RuntimeError,
reason="See Issue #2847, PR #2999, PR #4324",
)
def test_cross_module_exception_translator():
with pytest.raises(KeyError):
# translator registered in cross_module_tests
m.throw_should_be_translated_to_key_error()
def test_python_call_in_catch():
d = {}
assert m.python_call_in_destructor(d) is True
assert d["good"] is True
def ignore_pytest_unraisable_warning(f):
unraisable = "PytestUnraisableExceptionWarning"
if hasattr(pytest, unraisable): # Python >= 3.8 and pytest >= 6
dec = pytest.mark.filterwarnings(f"ignore::pytest.{unraisable}")
return dec(f)
return f
# TODO: find out why this fails on PyPy, https://foss.heptapod.net/pypy/pypy/-/issues/3583
@pytest.mark.xfail(env.PYPY, reason="Failure on PyPy 3.8 (7.3.7)", strict=False)
@ignore_pytest_unraisable_warning
def test_python_alreadyset_in_destructor(monkeypatch, capsys):
hooked = False
triggered = False
if hasattr(sys, "unraisablehook"): # Python 3.8+
hooked = True
# Don't take `sys.unraisablehook`, as that's overwritten by pytest
default_hook = sys.__unraisablehook__
def hook(unraisable_hook_args):
exc_type, exc_value, exc_tb, err_msg, obj = unraisable_hook_args
if obj == "already_set demo":
nonlocal triggered
triggered = True
default_hook(unraisable_hook_args)
return
# Use monkeypatch so pytest can apply and remove the patch as appropriate
monkeypatch.setattr(sys, "unraisablehook", hook)
assert m.python_alreadyset_in_destructor("already_set demo") is True
if hooked:
assert triggered is True
_, captured_stderr = capsys.readouterr()
assert captured_stderr.startswith("Exception ignored in: 'already_set demo'")
assert captured_stderr.rstrip().endswith("KeyError: 'bar'")
def test_exception_matches():
assert m.exception_matches()
assert m.exception_matches_base()
assert m.modulenotfound_exception_matches_base()
def test_custom(msg):
# Can we catch a MyException?
with pytest.raises(m.MyException) as excinfo:
m.throws1()
assert msg(excinfo.value) == "this error should go to a custom type"
# Can we translate to standard Python exceptions?
with pytest.raises(RuntimeError) as excinfo:
m.throws2()
assert msg(excinfo.value) == "this error should go to a standard Python exception"
# Can we handle unknown exceptions?
with pytest.raises(RuntimeError) as excinfo:
m.throws3()
assert msg(excinfo.value) == "Caught an unknown exception!"
# Can we delegate to another handler by rethrowing?
with pytest.raises(m.MyException) as excinfo:
m.throws4()
assert msg(excinfo.value) == "this error is rethrown"
# Can we fall-through to the default handler?
with pytest.raises(RuntimeError) as excinfo:
m.throws_logic_error()
assert (
msg(excinfo.value) == "this error should fall through to the standard handler"
)
# OverFlow error translation.
with pytest.raises(OverflowError) as excinfo:
m.throws_overflow_error()
# Can we handle a helper-declared exception?
with pytest.raises(m.MyException5) as excinfo:
m.throws5()
assert msg(excinfo.value) == "this is a helper-defined translated exception"
# Exception subclassing:
with pytest.raises(m.MyException5) as excinfo:
m.throws5_1()
assert msg(excinfo.value) == "MyException5 subclass"
assert isinstance(excinfo.value, m.MyException5_1)
with pytest.raises(m.MyException5_1) as excinfo:
m.throws5_1()
assert msg(excinfo.value) == "MyException5 subclass"
with pytest.raises(m.MyException5) as excinfo: # noqa: PT012
try:
m.throws5()
except m.MyException5_1 as err:
raise RuntimeError("Exception error: caught child from parent") from err
assert msg(excinfo.value) == "this is a helper-defined translated exception"
def test_nested_throws(capture):
"""Tests nested (e.g. C++ -> Python -> C++) exception handling"""
def throw_myex():
raise m.MyException("nested error")
def throw_myex5():
raise m.MyException5("nested error 5")
# In the comments below, the exception is caught in the first step, thrown in the last step
# C++ -> Python
with capture:
m.try_catch(m.MyException5, throw_myex5)
assert str(capture).startswith("MyException5: nested error 5")
# Python -> C++ -> Python
with pytest.raises(m.MyException) as excinfo:
m.try_catch(m.MyException5, throw_myex)
assert str(excinfo.value) == "nested error"
def pycatch(exctype, f, *args): # noqa: ARG001
try:
f(*args)
except m.MyException as e:
print(e)
# C++ -> Python -> C++ -> Python
with capture:
m.try_catch(
m.MyException5,
pycatch,
m.MyException,
m.try_catch,
m.MyException,
throw_myex5,
)
assert str(capture).startswith("MyException5: nested error 5")
# C++ -> Python -> C++
with capture:
m.try_catch(m.MyException, pycatch, m.MyException5, m.throws4)
assert capture == "this error is rethrown"
# Python -> C++ -> Python -> C++
with pytest.raises(m.MyException5) as excinfo:
m.try_catch(m.MyException, pycatch, m.MyException, m.throws5)
assert str(excinfo.value) == "this is a helper-defined translated exception"
def test_throw_nested_exception():
with pytest.raises(RuntimeError) as excinfo:
m.throw_nested_exception()
assert str(excinfo.value) == "Outer Exception"
assert str(excinfo.value.__cause__) == "Inner Exception"
# This can often happen if you wrap a pybind11 class in a Python wrapper
def test_invalid_repr():
class MyRepr:
def __repr__(self):
raise AttributeError("Example error")
with pytest.raises(TypeError):
m.simple_bool_passthrough(MyRepr())
def test_local_translator(msg):
"""Tests that a local translator works and that the local translator from
the cross module is not applied"""
with pytest.raises(RuntimeError) as excinfo:
m.throws6()
assert msg(excinfo.value) == "MyException6 only handled in this module"
with pytest.raises(RuntimeError) as excinfo:
m.throws_local_error()
assert not isinstance(excinfo.value, KeyError)
assert msg(excinfo.value) == "never caught"
with pytest.raises(Exception) as excinfo:
m.throws_local_simple_error()
assert not isinstance(excinfo.value, cm.LocalSimpleException)
assert msg(excinfo.value) == "this mod"
def test_error_already_set_message_with_unicode_surrogate(): # Issue #4288
assert m.error_already_set_what(RuntimeError, "\ud927") == (
"RuntimeError: \\ud927",
False,
)
def test_error_already_set_message_with_malformed_utf8():
assert m.error_already_set_what(RuntimeError, b"\x80") == (
"RuntimeError: b'\\x80'",
False,
)
class FlakyException(Exception):
def __init__(self, failure_point):
if failure_point == "failure_point_init":
raise ValueError("triggered_failure_point_init")
self.failure_point = failure_point
def __str__(self):
if self.failure_point == "failure_point_str":
raise ValueError("triggered_failure_point_str")
return "FlakyException.__str__"
@pytest.mark.parametrize(
("exc_type", "exc_value", "expected_what"),
[
(ValueError, "plain_str", "ValueError: plain_str"),
(ValueError, ("tuple_elem",), "ValueError: tuple_elem"),
(FlakyException, ("happy",), "FlakyException: FlakyException.__str__"),
],
)
def test_error_already_set_what_with_happy_exceptions(
exc_type, exc_value, expected_what
):
what, py_err_set_after_what = m.error_already_set_what(exc_type, exc_value)
assert not py_err_set_after_what
assert what == expected_what
@pytest.mark.skipif("env.PYPY", reason="PyErr_NormalizeException Segmentation fault")
def test_flaky_exception_failure_point_init():
with pytest.raises(RuntimeError) as excinfo:
m.error_already_set_what(FlakyException, ("failure_point_init",))
lines = str(excinfo.value).splitlines()
# PyErr_NormalizeException replaces the original FlakyException with ValueError:
assert lines[:3] == [
"pybind11::error_already_set: MISMATCH of original and normalized active exception types:"
" ORIGINAL FlakyException REPLACED BY ValueError: triggered_failure_point_init",
"",
"At:",
]
# Checking the first two lines of the traceback as formatted in error_string():
assert "test_exceptions.py(" in lines[3]
assert lines[3].endswith("): __init__")
assert lines[4].endswith("): test_flaky_exception_failure_point_init")
def test_flaky_exception_failure_point_str():
what, py_err_set_after_what = m.error_already_set_what(
FlakyException, ("failure_point_str",)
)
assert not py_err_set_after_what
lines = what.splitlines()
n = 3 if env.PYPY and len(lines) == 3 else 5
assert (
lines[:n]
== [
"FlakyException: <MESSAGE UNAVAILABLE DUE TO ANOTHER EXCEPTION>",
"",
"MESSAGE UNAVAILABLE DUE TO EXCEPTION: ValueError: triggered_failure_point_str",
"",
"At:",
][:n]
)
def test_cross_module_interleaved_error_already_set():
with pytest.raises(RuntimeError) as excinfo:
m.test_cross_module_interleaved_error_already_set()
assert str(excinfo.value) in (
"2nd error.", # Almost all platforms.
"RuntimeError: 2nd error.", # Some PyPy builds (seen under macOS).
)
def test_error_already_set_double_restore():
m.test_error_already_set_double_restore(True) # dry_run
with pytest.raises(RuntimeError) as excinfo:
m.test_error_already_set_double_restore(False)
assert str(excinfo.value) == (
"Internal error: pybind11::detail::error_fetch_and_normalize::restore()"
" called a second time. ORIGINAL ERROR: ValueError: Random error."
)
def test_pypy_oserror_normalization():
# https://github.com/pybind/pybind11/issues/4075
what = m.test_pypy_oserror_normalization()
assert "this_filename_must_not_exist" in what
def test_fn_cast_int_exception():
with pytest.raises(RuntimeError) as excinfo:
m.test_fn_cast_int(lambda: None)
assert str(excinfo.value).startswith(
"Unable to cast Python instance of type <class 'NoneType'> to C++ type"
)