/*
tests/test_custom-exceptions.cpp -- exception translation
Copyright (c) 2016 Pim Schellart
All rights reserved. Use of this source code is governed by a
BSD-style license that can be found in the LICENSE file.
*/
#include
#include "test_exceptions.h"
#include "local_bindings.h"
#include "pybind11_tests.h"
#include
#include
#include
// A type that should be raised as an exception in Python
class MyException : public std::exception {
public:
explicit MyException(const char *m) : message{m} {}
const char *what() const noexcept override { return message.c_str(); }
private:
std::string message = "";
};
class MyExceptionUseDeprecatedOperatorCall : public MyException {
using MyException::MyException;
};
// A type that should be translated to a standard Python exception
class MyException2 : public std::exception {
public:
explicit MyException2(const char *m) : message{m} {}
const char *what() const noexcept override { return message.c_str(); }
private:
std::string message = "";
};
// A type that is not derived from std::exception (and is thus unknown)
class MyException3 {
public:
explicit MyException3(const char *m) : message{m} {}
virtual const char *what() const noexcept { return message.c_str(); }
// Rule of 5 BEGIN: to preempt compiler warnings.
MyException3(const MyException3 &) = default;
MyException3(MyException3 &&) = default;
MyException3 &operator=(const MyException3 &) = default;
MyException3 &operator=(MyException3 &&) = default;
virtual ~MyException3() = default;
// Rule of 5 END.
private:
std::string message = "";
};
// A type that should be translated to MyException
// and delegated to its exception translator
class MyException4 : public std::exception {
public:
explicit MyException4(const char *m) : message{m} {}
const char *what() const noexcept override { return message.c_str(); }
private:
std::string message = "";
};
// Like the above, but declared via the helper function
class MyException5 : public std::logic_error {
public:
explicit MyException5(const std::string &what) : std::logic_error(what) {}
};
// Inherits from MyException5
class MyException5_1 : public MyException5 {
using MyException5::MyException5;
};
// Exception that will be caught via the module local translator.
class MyException6 : public std::exception {
public:
explicit MyException6(const char *m) : message{m} {}
const char *what() const noexcept override { return message.c_str(); }
private:
std::string message = "";
};
struct PythonCallInDestructor {
explicit PythonCallInDestructor(const py::dict &d) : d(d) {}
~PythonCallInDestructor() { d["good"] = true; }
py::dict d;
};
struct PythonAlreadySetInDestructor {
explicit PythonAlreadySetInDestructor(const py::str &s) : s(s) {}
~PythonAlreadySetInDestructor() {
py::dict foo;
try {
// Assign to a py::object to force read access of nonexistent dict entry
py::object o = foo["bar"];
} catch (py::error_already_set &ex) {
ex.discard_as_unraisable(s);
}
}
py::str s;
};
struct CustomData {
explicit CustomData(const std::string &a) : a(a) {}
std::string a;
};
struct MyException7 {
explicit MyException7(const CustomData &message) : message(message) {}
CustomData message;
};
TEST_SUBMODULE(exceptions, m) {
m.def("throw_std_exception",
[]() { throw std::runtime_error("This exception was intentionally thrown."); });
// PLEASE KEEP IN SYNC with docs/advanced/exceptions.rst
PYBIND11_CONSTINIT static py::gil_safe_call_once_and_store ex_storage;
ex_storage.call_once_and_store_result(
[&]() { return py::exception(m, "MyException"); });
py::register_exception_translator([](std::exception_ptr p) {
try {
if (p) {
std::rethrow_exception(p);
}
} catch (const MyException &e) {
// Set MyException as the active python error
py::set_error(ex_storage.get_stored(), e.what());
}
});
// Same as above, but using the deprecated `py::exception<>::operator()`
// We want to be sure it still works, until it's removed.
static const auto *const exd = new py::exception(
m, "MyExceptionUseDeprecatedOperatorCall");
py::register_exception_translator([](std::exception_ptr p) {
try {
if (p) {
std::rethrow_exception(p);
}
} catch (const MyExceptionUseDeprecatedOperatorCall &e) {
#if defined(__INTEL_COMPILER) || defined(__NVCOMPILER)
// It is not worth the trouble dealing with warning suppressions for these compilers.
// Falling back to the recommended approach to keep the test code simple.
py::set_error(*exd, e.what());
#else
PYBIND11_WARNING_PUSH
PYBIND11_WARNING_DISABLE_CLANG("-Wdeprecated-declarations")
PYBIND11_WARNING_DISABLE_GCC("-Wdeprecated-declarations")
PYBIND11_WARNING_DISABLE_MSVC(4996)
(*exd)(e.what());
PYBIND11_WARNING_POP
#endif
}
});
// register new translator for MyException2
// no need to store anything here because this type will
// never by visible from Python
py::register_exception_translator([](std::exception_ptr p) {
try {
if (p) {
std::rethrow_exception(p);
}
} catch (const MyException2 &e) {
// Translate this exception to a standard RuntimeError
py::set_error(PyExc_RuntimeError, e.what());
}
});
// register new translator for MyException4
// which will catch it and delegate to the previously registered
// translator for MyException by throwing a new exception
py::register_exception_translator([](std::exception_ptr p) {
try {
if (p) {
std::rethrow_exception(p);
}
} catch (const MyException4 &e) {
throw MyException(e.what());
}
});
// A simple exception translation:
auto ex5 = py::register_exception(m, "MyException5");
// A slightly more complicated one that declares MyException5_1 as a subclass of MyException5
py::register_exception(m, "MyException5_1", ex5.ptr());
// py::register_local_exception(m, "LocalSimpleException")
py::register_local_exception_translator([](std::exception_ptr p) {
try {
if (p) {
std::rethrow_exception(p);
}
} catch (const MyException6 &e) {
py::set_error(PyExc_RuntimeError, e.what());
}
});
m.def("throws1",
[]() { throw MyException("this error should go to py::exception"); });
m.def("throws1d", []() {
throw MyExceptionUseDeprecatedOperatorCall(
"this error should go to py::exception");
});
m.def("throws2",
[]() { throw MyException2("this error should go to a standard Python exception"); });
m.def("throws3", []() { throw MyException3("this error cannot be translated"); });
m.def("throws4", []() { throw MyException4("this error is rethrown"); });
m.def("throws5",
[]() { throw MyException5("this is a helper-defined translated exception"); });
m.def("throws5_1", []() { throw MyException5_1("MyException5 subclass"); });
m.def("throws6", []() { throw MyException6("MyException6 only handled in this module"); });
m.def("throws_logic_error", []() {
throw std::logic_error("this error should fall through to the standard handler");
});
m.def("throws_overflow_error", []() { throw std::overflow_error(""); });
m.def("throws_local_error", []() { throw LocalException("never caught"); });
m.def("throws_local_simple_error", []() { throw LocalSimpleException("this mod"); });
m.def("exception_matches", []() {
py::dict foo;
try {
// Assign to a py::object to force read access of nonexistent dict entry
py::object o = foo["bar"];
} catch (py::error_already_set &ex) {
if (!ex.matches(PyExc_KeyError)) {
throw;
}
return true;
}
return false;
});
m.def("exception_matches_base", []() {
py::dict foo;
try {
// Assign to a py::object to force read access of nonexistent dict entry
py::object o = foo["bar"];
} catch (py::error_already_set &ex) {
if (!ex.matches(PyExc_Exception)) {
throw;
}
return true;
}
return false;
});
m.def("modulenotfound_exception_matches_base", []() {
try {
// On Python >= 3.6, this raises a ModuleNotFoundError, a subclass of ImportError
py::module_::import("nonexistent");
} catch (py::error_already_set &ex) {
if (!ex.matches(PyExc_ImportError)) {
throw;
}
return true;
}
return false;
});
m.def("throw_already_set", [](bool err) {
if (err) {
py::set_error(PyExc_ValueError, "foo");
}
try {
throw py::error_already_set();
} catch (const std::runtime_error &e) {
if ((err && e.what() != std::string("ValueError: foo"))
|| (!err
&& e.what()
!= std::string("Internal error: pybind11::error_already_set called "
"while Python error indicator not set."))) {
PyErr_Clear();
throw std::runtime_error("error message mismatch");
}
}
PyErr_Clear();
if (err) {
py::set_error(PyExc_ValueError, "foo");
}
throw py::error_already_set();
});
m.def("python_call_in_destructor", [](const py::dict &d) {
bool retval = false;
try {
PythonCallInDestructor set_dict_in_destructor(d);
py::set_error(PyExc_ValueError, "foo");
throw py::error_already_set();
} catch (const py::error_already_set &) {
retval = true;
}
return retval;
});
m.def("python_alreadyset_in_destructor", [](const py::str &s) {
PythonAlreadySetInDestructor alreadyset_in_destructor(s);
return true;
});
// test_nested_throws
m.def("try_catch",
[m](const py::object &exc_type, const py::function &f, const py::args &args) {
try {
f(*args);
} catch (py::error_already_set &ex) {
if (ex.matches(exc_type)) {
py::print(ex.what());
} else {
// Simply `throw;` also works and is better, but using `throw ex;`
// here to cover that situation (as observed in the wild).
throw ex; // Invokes the copy ctor.
}
}
});
// Test repr that cannot be displayed
m.def("simple_bool_passthrough", [](bool x) { return x; });
m.def("throw_should_be_translated_to_key_error", []() { throw shared_exception(); });
m.def("raise_from", []() {
py::set_error(PyExc_ValueError, "inner");
py::raise_from(PyExc_ValueError, "outer");
throw py::error_already_set();
});
m.def("raise_from_already_set", []() {
try {
py::set_error(PyExc_ValueError, "inner");
throw py::error_already_set();
} catch (py::error_already_set &e) {
py::raise_from(e, PyExc_ValueError, "outer");
throw py::error_already_set();
}
});
m.def("throw_nested_exception", []() {
try {
throw std::runtime_error("Inner Exception");
} catch (const std::runtime_error &) {
std::throw_with_nested(std::runtime_error("Outer Exception"));
}
});
m.def("error_already_set_what", [](const py::object &exc_type, const py::object &exc_value) {
py::set_error(exc_type, exc_value);
std::string what = py::error_already_set().what();
bool py_err_set_after_what = (PyErr_Occurred() != nullptr);
PyErr_Clear();
return py::make_tuple(std::move(what), py_err_set_after_what);
});
m.def("test_cross_module_interleaved_error_already_set", []() {
auto cm = py::module_::import("cross_module_interleaved_error_already_set");
auto interleaved_error_already_set
= reinterpret_cast(PyLong_AsVoidPtr(cm.attr("funcaddr").ptr()));
interleaved_error_already_set();
});
m.def("test_error_already_set_double_restore", [](bool dry_run) {
py::set_error(PyExc_ValueError, "Random error.");
py::error_already_set e;
e.restore();
PyErr_Clear();
if (!dry_run) {
e.restore();
}
});
// https://github.com/pybind/pybind11/issues/4075
m.def("test_pypy_oserror_normalization", []() {
try {
py::module_::import("io").attr("open")("this_filename_must_not_exist", "r");
} catch (const py::error_already_set &e) {
return py::str(e.what()); // str must be built before e goes out of scope.
}
return py::str("UNEXPECTED");
});
m.def("test_fn_cast_int", [](const py::function &fn) {
// function returns None instead of int, should give a useful error message
fn().cast();
});
// m.def("pass_exception_void", [](const py::exception&) {}); // Does not compile.
m.def("return_exception_void", []() { return py::exception(); });
m.def("throws7", []() {
auto data = CustomData("abc");
throw MyException7(data);
});
py::class_(m, "CustomData", py::module_local())
.def(py::init())
.def_readwrite("a", &CustomData::a);
PYBIND11_CONSTINIT static py::gil_safe_call_once_and_store
PythonMyException7_storage;
PythonMyException7_storage.call_once_and_store_result([&]() {
auto mod = py::module_::import("custom_exceptions");
py::object obj = mod.attr("PythonMyException7");
return obj;
});
py::register_local_exception_translator([](std::exception_ptr p) {
try {
if (p) {
std::rethrow_exception(p);
}
} catch (const MyException7 &e) {
auto exc_type = PythonMyException7_storage.get_stored();
py::object exc_inst = exc_type(e.message);
PyErr_SetObject(PyExc_Exception, exc_inst.ptr());
}
});
}