teak-llvm/libcxx/test/std/utilities/variant/variant.visit/visit.pass.cpp
Louis Dionne f5f2f77755 [libc++] Fix XFAILs on macOS when exceptions are disabled
Some tests are marked as failing on platforms where the dylib does not
provide the required exception classes. However, when testing with
exceptions disabled, those tests shouldn't be marked as failing.

llvm-svn: 353210
2019-02-05 20:11:58 +00:00

316 lines
8.7 KiB
C++

// -*- C++ -*-
//===----------------------------------------------------------------------===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
// UNSUPPORTED: c++98, c++03, c++11, c++14
// XFAIL: dylib-has-no-bad_variant_access && !libcpp-no-exceptions
// <variant>
// template <class Visitor, class... Variants>
// constexpr see below visit(Visitor&& vis, Variants&&... vars);
#include <cassert>
#include <memory>
#include <string>
#include <type_traits>
#include <utility>
#include <variant>
#include "test_macros.h"
#include "type_id.h"
#include "variant_test_helpers.hpp"
enum CallType : unsigned {
CT_None,
CT_NonConst = 1,
CT_Const = 2,
CT_LValue = 4,
CT_RValue = 8
};
inline constexpr CallType operator|(CallType LHS, CallType RHS) {
return static_cast<CallType>(static_cast<unsigned>(LHS) |
static_cast<unsigned>(RHS));
}
struct ForwardingCallObject {
template <class... Args> bool operator()(Args &&...) & {
set_call<Args &&...>(CT_NonConst | CT_LValue);
return true;
}
template <class... Args> bool operator()(Args &&...) const & {
set_call<Args &&...>(CT_Const | CT_LValue);
return true;
}
// Don't allow the call operator to be invoked as an rvalue.
template <class... Args> bool operator()(Args &&...) && {
set_call<Args &&...>(CT_NonConst | CT_RValue);
return true;
}
template <class... Args> bool operator()(Args &&...) const && {
set_call<Args &&...>(CT_Const | CT_RValue);
return true;
}
template <class... Args> static void set_call(CallType type) {
assert(last_call_type == CT_None);
assert(last_call_args == nullptr);
last_call_type = type;
last_call_args = std::addressof(makeArgumentID<Args...>());
}
template <class... Args> static bool check_call(CallType type) {
bool result = last_call_type == type && last_call_args &&
*last_call_args == makeArgumentID<Args...>();
last_call_type = CT_None;
last_call_args = nullptr;
return result;
}
static CallType last_call_type;
static const TypeID *last_call_args;
};
CallType ForwardingCallObject::last_call_type = CT_None;
const TypeID *ForwardingCallObject::last_call_args = nullptr;
void test_call_operator_forwarding() {
using Fn = ForwardingCallObject;
Fn obj{};
const Fn &cobj = obj;
{ // test call operator forwarding - no variant
std::visit(obj);
assert(Fn::check_call<>(CT_NonConst | CT_LValue));
std::visit(cobj);
assert(Fn::check_call<>(CT_Const | CT_LValue));
std::visit(std::move(obj));
assert(Fn::check_call<>(CT_NonConst | CT_RValue));
std::visit(std::move(cobj));
assert(Fn::check_call<>(CT_Const | CT_RValue));
}
{ // test call operator forwarding - single variant, single arg
using V = std::variant<int>;
V v(42);
std::visit(obj, v);
assert(Fn::check_call<int &>(CT_NonConst | CT_LValue));
std::visit(cobj, v);
assert(Fn::check_call<int &>(CT_Const | CT_LValue));
std::visit(std::move(obj), v);
assert(Fn::check_call<int &>(CT_NonConst | CT_RValue));
std::visit(std::move(cobj), v);
assert(Fn::check_call<int &>(CT_Const | CT_RValue));
}
{ // test call operator forwarding - single variant, multi arg
using V = std::variant<int, long, double>;
V v(42l);
std::visit(obj, v);
assert(Fn::check_call<long &>(CT_NonConst | CT_LValue));
std::visit(cobj, v);
assert(Fn::check_call<long &>(CT_Const | CT_LValue));
std::visit(std::move(obj), v);
assert(Fn::check_call<long &>(CT_NonConst | CT_RValue));
std::visit(std::move(cobj), v);
assert(Fn::check_call<long &>(CT_Const | CT_RValue));
}
{ // test call operator forwarding - multi variant, multi arg
using V = std::variant<int, long, double>;
using V2 = std::variant<int *, std::string>;
V v(42l);
V2 v2("hello");
std::visit(obj, v, v2);
assert((Fn::check_call<long &, std::string &>(CT_NonConst | CT_LValue)));
std::visit(cobj, v, v2);
assert((Fn::check_call<long &, std::string &>(CT_Const | CT_LValue)));
std::visit(std::move(obj), v, v2);
assert((Fn::check_call<long &, std::string &>(CT_NonConst | CT_RValue)));
std::visit(std::move(cobj), v, v2);
assert((Fn::check_call<long &, std::string &>(CT_Const | CT_RValue)));
}
}
void test_argument_forwarding() {
using Fn = ForwardingCallObject;
Fn obj{};
const auto Val = CT_LValue | CT_NonConst;
{ // single argument - value type
using V = std::variant<int>;
V v(42);
const V &cv = v;
std::visit(obj, v);
assert(Fn::check_call<int &>(Val));
std::visit(obj, cv);
assert(Fn::check_call<const int &>(Val));
std::visit(obj, std::move(v));
assert(Fn::check_call<int &&>(Val));
std::visit(obj, std::move(cv));
assert(Fn::check_call<const int &&>(Val));
}
#if !defined(TEST_VARIANT_HAS_NO_REFERENCES)
{ // single argument - lvalue reference
using V = std::variant<int &>;
int x = 42;
V v(x);
const V &cv = v;
std::visit(obj, v);
assert(Fn::check_call<int &>(Val));
std::visit(obj, cv);
assert(Fn::check_call<int &>(Val));
std::visit(obj, std::move(v));
assert(Fn::check_call<int &>(Val));
std::visit(obj, std::move(cv));
assert(Fn::check_call<int &>(Val));
}
{ // single argument - rvalue reference
using V = std::variant<int &&>;
int x = 42;
V v(std::move(x));
const V &cv = v;
std::visit(obj, v);
assert(Fn::check_call<int &>(Val));
std::visit(obj, cv);
assert(Fn::check_call<int &>(Val));
std::visit(obj, std::move(v));
assert(Fn::check_call<int &&>(Val));
std::visit(obj, std::move(cv));
assert(Fn::check_call<int &&>(Val));
}
{ // multi argument - multi variant
using S = const std::string &;
using V = std::variant<int, S, long &&>;
const std::string str = "hello";
long l = 43;
V v1(42);
const V &cv1 = v1;
V v2(str);
const V &cv2 = v2;
V v3(std::move(l));
const V &cv3 = v3;
std::visit(obj, v1, v2, v3);
assert((Fn::check_call<int &, S, long &>(Val)));
std::visit(obj, cv1, cv2, std::move(v3));
assert((Fn::check_call<const int &, S, long &&>(Val)));
}
#endif
}
struct ReturnFirst {
template <class... Args> constexpr int operator()(int f, Args &&...) const {
return f;
}
};
struct ReturnArity {
template <class... Args> constexpr int operator()(Args &&...) const {
return sizeof...(Args);
}
};
void test_constexpr() {
constexpr ReturnFirst obj{};
constexpr ReturnArity aobj{};
{
using V = std::variant<int>;
constexpr V v(42);
static_assert(std::visit(obj, v) == 42, "");
}
{
using V = std::variant<short, long, char>;
constexpr V v(42l);
static_assert(std::visit(obj, v) == 42, "");
}
{
using V1 = std::variant<int>;
using V2 = std::variant<int, char *, long long>;
using V3 = std::variant<bool, int, int>;
constexpr V1 v1;
constexpr V2 v2(nullptr);
constexpr V3 v3;
static_assert(std::visit(aobj, v1, v2, v3) == 3, "");
}
{
using V1 = std::variant<int>;
using V2 = std::variant<int, char *, long long>;
using V3 = std::variant<void *, int, int>;
constexpr V1 v1;
constexpr V2 v2(nullptr);
constexpr V3 v3;
static_assert(std::visit(aobj, v1, v2, v3) == 3, "");
}
}
void test_exceptions() {
#ifndef TEST_HAS_NO_EXCEPTIONS
ReturnArity obj{};
auto test = [&](auto &&... args) {
try {
std::visit(obj, args...);
} catch (const std::bad_variant_access &) {
return true;
} catch (...) {
}
return false;
};
{
using V = std::variant<int, MakeEmptyT>;
V v;
makeEmpty(v);
assert(test(v));
}
{
using V = std::variant<int, MakeEmptyT>;
using V2 = std::variant<long, std::string, void *>;
V v;
makeEmpty(v);
V2 v2("hello");
assert(test(v, v2));
}
{
using V = std::variant<int, MakeEmptyT>;
using V2 = std::variant<long, std::string, void *>;
V v;
makeEmpty(v);
V2 v2("hello");
assert(test(v2, v));
}
{
using V = std::variant<int, MakeEmptyT>;
using V2 = std::variant<long, std::string, void *, MakeEmptyT>;
V v;
makeEmpty(v);
V2 v2;
makeEmpty(v2);
assert(test(v, v2));
}
#endif
}
// See https://bugs.llvm.org/show_bug.cgi?id=31916
void test_caller_accepts_nonconst() {
struct A {};
struct Visitor {
void operator()(A&) {}
};
std::variant<A> v;
std::visit(Visitor{}, v);
}
int main(int, char**) {
test_call_operator_forwarding();
test_argument_forwarding();
test_constexpr();
test_exceptions();
test_caller_accepts_nonconst();
return 0;
}