// Copyright 2018 The Abseil Authors.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// https://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
#include "absl/container/internal/compressed_tuple.h"
#include <memory>
#include <string>
#include "gmock/gmock.h"
#include "gtest/gtest.h"
#include "absl/memory/memory.h"
#include "absl/utility/utility.h"
namespace absl {
namespace container_internal {
namespace {
enum class CallType { kConstRef, kConstMove };
template <int>
struct Empty {
constexpr CallType value() const& { return CallType::kConstRef; }
constexpr CallType value() const&& { return CallType::kConstMove; }
};
template <typename T>
struct NotEmpty {
T value;
};
template <typename T, typename U>
struct TwoValues {
T value1;
U value2;
};
TEST(CompressedTupleTest, Sizeof) {
EXPECT_EQ(sizeof(int), sizeof(CompressedTuple<int>));
EXPECT_EQ(sizeof(int), sizeof(CompressedTuple<int, Empty<0>>));
EXPECT_EQ(sizeof(int), sizeof(CompressedTuple<int, Empty<0>, Empty<1>>));
EXPECT_EQ(sizeof(int),
sizeof(CompressedTuple<int, Empty<0>, Empty<1>, Empty<2>>));
EXPECT_EQ(sizeof(TwoValues<int, double>),
sizeof(CompressedTuple<int, NotEmpty<double>>));
EXPECT_EQ(sizeof(TwoValues<int, double>),
sizeof(CompressedTuple<int, Empty<0>, NotEmpty<double>>));
EXPECT_EQ(sizeof(TwoValues<int, double>),
sizeof(CompressedTuple<int, Empty<0>, NotEmpty<double>, Empty<1>>));
}
TEST(CompressedTupleTest, Access) {
struct S {
std::string x;
};
CompressedTuple<int, Empty<0>, S> x(7, {}, S{"ABC"});
EXPECT_EQ(sizeof(x), sizeof(TwoValues<int, S>));
EXPECT_EQ(7, x.get<0>());
EXPECT_EQ("ABC", x.get<2>().x);
}
TEST(CompressedTupleTest, NonClasses) {
CompressedTuple<int, const char*> x(7, "ABC");
EXPECT_EQ(7, x.get<0>());
EXPECT_STREQ("ABC", x.get<1>());
}
TEST(CompressedTupleTest, MixClassAndNonClass) {
CompressedTuple<int, const char*, Empty<0>, NotEmpty<double>> x(7, "ABC", {},
{1.25});
struct Mock {
int v;
const char* p;
double d;
};
EXPECT_EQ(sizeof(x), sizeof(Mock));
EXPECT_EQ(7, x.get<0>());
EXPECT_STREQ("ABC", x.get<1>());
EXPECT_EQ(1.25, x.get<3>().value);
}
TEST(CompressedTupleTest, Nested) {
CompressedTuple<int, CompressedTuple<int>,
CompressedTuple<int, CompressedTuple<int>>>
x(1, CompressedTuple<int>(2),
CompressedTuple<int, CompressedTuple<int>>(3, CompressedTuple<int>(4)));
EXPECT_EQ(1, x.get<0>());
EXPECT_EQ(2, x.get<1>().get<0>());
EXPECT_EQ(3, x.get<2>().get<0>());
EXPECT_EQ(4, x.get<2>().get<1>().get<0>());
CompressedTuple<Empty<0>, Empty<0>,
CompressedTuple<Empty<0>, CompressedTuple<Empty<0>>>>
y;
std::set<Empty<0>*> empties{&y.get<0>(), &y.get<1>(), &y.get<2>().get<0>(),
&y.get<2>().get<1>().get<0>()};
#ifdef _MSC_VER
// MSVC has a bug where many instances of the same base class are layed out in
// the same address when using __declspec(empty_bases).
// This will be fixed in a future version of MSVC.
int expected = 1;
#else
int expected = 4;
#endif
EXPECT_EQ(expected, sizeof(y));
EXPECT_EQ(expected, empties.size());
EXPECT_EQ(sizeof(y), sizeof(Empty<0>) * empties.size());
EXPECT_EQ(4 * sizeof(char),
sizeof(CompressedTuple<CompressedTuple<char, char>,
CompressedTuple<char, char>>));
EXPECT_TRUE(
(std::is_empty<CompressedTuple<CompressedTuple<Empty<0>>,
CompressedTuple<Empty<1>>>>::value));
}
TEST(CompressedTupleTest, Reference) {
int i = 7;
std::string s = "Very long std::string that goes in the heap";
CompressedTuple<int, int&, std::string, std::string&> x(i, i, s, s);
// Sanity check. We should have not moved from `s`
EXPECT_EQ(s, "Very long std::string that goes in the heap");
EXPECT_EQ(x.get<0>(), x.get<1>());
EXPECT_NE(&x.get<0>(), &x.get<1>());
EXPECT_EQ(&x.get<1>(), &i);
EXPECT_EQ(x.get<2>(), x.get<3>());
EXPECT_NE(&x.get<2>(), &x.get<3>());
EXPECT_EQ(&x.get<3>(), &s);
}
TEST(CompressedTupleTest, NoElements) {
CompressedTuple<> x;
static_cast<void>(x); // Silence -Wunused-variable.
EXPECT_TRUE(std::is_empty<CompressedTuple<>>::value);
}
TEST(CompressedTupleTest, MoveOnlyElements) {
CompressedTuple<std::unique_ptr<std::string>> str_tup(
absl::make_unique<std::string>("str"));
CompressedTuple<CompressedTuple<std::unique_ptr<std::string>>,
std::unique_ptr<int>>
x(std::move(str_tup), absl::make_unique<int>(5));
EXPECT_EQ(*x.get<0>().get<0>(), "str");
EXPECT_EQ(*x.get<1>(), 5);
std::unique_ptr<std::string> x0 = std::move(x.get<0>()).get<0>();
std::unique_ptr<int> x1 = std::move(x).get<1>();
EXPECT_EQ(*x0, "str");
EXPECT_EQ(*x1, 5);
}
TEST(CompressedTupleTest, Constexpr) {
constexpr CompressedTuple<int, double, CompressedTuple<int>, Empty<0>> x(
7, 1.25, CompressedTuple<int>(5), {});
constexpr int x0 = x.get<0>();
constexpr double x1 = x.get<1>();
constexpr int x2 = x.get<2>().get<0>();
constexpr CallType x3 = x.get<3>().value();
EXPECT_EQ(x0, 7);
EXPECT_EQ(x1, 1.25);
EXPECT_EQ(x2, 5);
EXPECT_EQ(x3, CallType::kConstRef);
#if defined(__clang__)
// An apparent bug in earlier versions of gcc claims these are ambiguous.
constexpr int x2m = absl::move(x.get<2>()).get<0>();
constexpr CallType x3m = absl::move(x).get<3>().value();
EXPECT_EQ(x2m, 5);
EXPECT_EQ(x3m, CallType::kConstMove);
#endif
}
#if defined(__clang__) || defined(__GNUC__)
TEST(CompressedTupleTest, EmptyFinalClass) {
struct S final {
int f() const { return 5; }
};
CompressedTuple<S> x;
EXPECT_EQ(x.get<0>().f(), 5);
}
#endif
} // namespace
} // namespace container_internal
} // namespace absl
