80 lines
2.1 KiB
C++
80 lines
2.1 KiB
C++
// Copyright 2023 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/utility/internal/if_constexpr.h"
|
|
|
|
#include <utility>
|
|
|
|
#include "gtest/gtest.h"
|
|
|
|
namespace {
|
|
|
|
struct Empty {};
|
|
struct HasFoo {
|
|
int foo() const { return 1; }
|
|
};
|
|
|
|
TEST(IfConstexpr, Basic) {
|
|
int i = 0;
|
|
absl::utility_internal::IfConstexpr<false>(
|
|
[&](const auto& t) { i = t.foo(); }, Empty{});
|
|
EXPECT_EQ(i, 0);
|
|
|
|
absl::utility_internal::IfConstexpr<false>(
|
|
[&](const auto& t) { i = t.foo(); }, HasFoo{});
|
|
EXPECT_EQ(i, 0);
|
|
|
|
absl::utility_internal::IfConstexpr<true>(
|
|
[&](const auto& t) { i = t.foo(); }, HasFoo{});
|
|
EXPECT_EQ(i, 1);
|
|
}
|
|
|
|
TEST(IfConstexprElse, Basic) {
|
|
EXPECT_EQ(absl::utility_internal::IfConstexprElse<false>(
|
|
[&](const auto& t) { return t.foo(); }, [&](const auto&) { return 2; },
|
|
Empty{}), 2);
|
|
|
|
EXPECT_EQ(absl::utility_internal::IfConstexprElse<false>(
|
|
[&](const auto& t) { return t.foo(); }, [&](const auto&) { return 2; },
|
|
HasFoo{}), 2);
|
|
|
|
EXPECT_EQ(absl::utility_internal::IfConstexprElse<true>(
|
|
[&](const auto& t) { return t.foo(); }, [&](const auto&) { return 2; },
|
|
HasFoo{}), 1);
|
|
}
|
|
|
|
struct HasFooRValue {
|
|
int foo() && { return 1; }
|
|
};
|
|
struct RValueFunc {
|
|
void operator()(HasFooRValue&& t) && { *i = std::move(t).foo(); }
|
|
|
|
int* i = nullptr;
|
|
};
|
|
|
|
TEST(IfConstexpr, RValues) {
|
|
int i = 0;
|
|
RValueFunc func = {&i};
|
|
absl::utility_internal::IfConstexpr<false>(
|
|
std::move(func), HasFooRValue{});
|
|
EXPECT_EQ(i, 0);
|
|
|
|
func = RValueFunc{&i};
|
|
absl::utility_internal::IfConstexpr<true>(
|
|
std::move(func), HasFooRValue{});
|
|
EXPECT_EQ(i, 1);
|
|
}
|
|
|
|
} // namespace
|