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Diffstat (limited to 'third_party/abseil-cpp/absl/utility/utility_test.cc')
| -rw-r--r-- | third_party/abseil-cpp/absl/utility/utility_test.cc | 376 |
1 files changed, 376 insertions, 0 deletions
diff --git a/third_party/abseil-cpp/absl/utility/utility_test.cc b/third_party/abseil-cpp/absl/utility/utility_test.cc new file mode 100644 index 0000000000..f044ad644a --- /dev/null +++ b/third_party/abseil-cpp/absl/utility/utility_test.cc @@ -0,0 +1,376 @@ +// Copyright 2017 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/utility.h" + +#include <sstream> +#include <string> +#include <tuple> +#include <type_traits> +#include <vector> + +#include "gmock/gmock.h" +#include "gtest/gtest.h" +#include "absl/base/attributes.h" +#include "absl/memory/memory.h" +#include "absl/strings/str_cat.h" + +namespace { + +#ifdef _MSC_VER +// Warnings for unused variables in this test are false positives. On other +// platforms, they are suppressed by ABSL_ATTRIBUTE_UNUSED, but that doesn't +// work on MSVC. +// Both the unused variables and the name length warnings are due to calls +// to absl::make_index_sequence with very large values, creating very long type +// names. The resulting warnings are so long they make build output unreadable. +#pragma warning( push ) +#pragma warning( disable : 4503 ) // decorated name length exceeded +#pragma warning( disable : 4101 ) // unreferenced local variable +#endif // _MSC_VER + +using ::testing::ElementsAre; +using ::testing::Pointee; +using ::testing::StaticAssertTypeEq; + +TEST(IntegerSequenceTest, ValueType) { + StaticAssertTypeEq<int, absl::integer_sequence<int>::value_type>(); + StaticAssertTypeEq<char, absl::integer_sequence<char>::value_type>(); +} + +TEST(IntegerSequenceTest, Size) { + EXPECT_EQ(0, (absl::integer_sequence<int>::size())); + EXPECT_EQ(1, (absl::integer_sequence<int, 0>::size())); + EXPECT_EQ(1, (absl::integer_sequence<int, 1>::size())); + EXPECT_EQ(2, (absl::integer_sequence<int, 1, 2>::size())); + EXPECT_EQ(3, (absl::integer_sequence<int, 0, 1, 2>::size())); + EXPECT_EQ(3, (absl::integer_sequence<int, -123, 123, 456>::size())); + constexpr size_t sz = absl::integer_sequence<int, 0, 1>::size(); + EXPECT_EQ(2, sz); +} + +TEST(IntegerSequenceTest, MakeIndexSequence) { + StaticAssertTypeEq<absl::index_sequence<>, absl::make_index_sequence<0>>(); + StaticAssertTypeEq<absl::index_sequence<0>, absl::make_index_sequence<1>>(); + StaticAssertTypeEq<absl::index_sequence<0, 1>, + absl::make_index_sequence<2>>(); + StaticAssertTypeEq<absl::index_sequence<0, 1, 2>, + absl::make_index_sequence<3>>(); +} + +TEST(IntegerSequenceTest, MakeIntegerSequence) { + StaticAssertTypeEq<absl::integer_sequence<int>, + absl::make_integer_sequence<int, 0>>(); + StaticAssertTypeEq<absl::integer_sequence<int, 0>, + absl::make_integer_sequence<int, 1>>(); + StaticAssertTypeEq<absl::integer_sequence<int, 0, 1>, + absl::make_integer_sequence<int, 2>>(); + StaticAssertTypeEq<absl::integer_sequence<int, 0, 1, 2>, + absl::make_integer_sequence<int, 3>>(); +} + +template <typename... Ts> +class Counter {}; + +template <size_t... Is> +void CountAll(absl::index_sequence<Is...>) { + // We only need an alias here, but instantiate a variable to silence warnings + // for unused typedefs in some compilers. + ABSL_ATTRIBUTE_UNUSED Counter<absl::make_index_sequence<Is>...> seq; +} + +// This test verifies that absl::make_index_sequence can handle large arguments +// without blowing up template instantiation stack, going OOM or taking forever +// to compile (there is hard 15 minutes limit imposed by forge). +TEST(IntegerSequenceTest, MakeIndexSequencePerformance) { + // O(log N) template instantiations. + // We only need an alias here, but instantiate a variable to silence warnings + // for unused typedefs in some compilers. + ABSL_ATTRIBUTE_UNUSED absl::make_index_sequence<(1 << 16) - 1> seq; + // O(N) template instantiations. + CountAll(absl::make_index_sequence<(1 << 8) - 1>()); +} + +template <typename F, typename Tup, size_t... Is> +auto ApplyFromTupleImpl(F f, const Tup& tup, absl::index_sequence<Is...>) + -> decltype(f(std::get<Is>(tup)...)) { + return f(std::get<Is>(tup)...); +} + +template <typename Tup> +using TupIdxSeq = absl::make_index_sequence<std::tuple_size<Tup>::value>; + +template <typename F, typename Tup> +auto ApplyFromTuple(F f, const Tup& tup) + -> decltype(ApplyFromTupleImpl(f, tup, TupIdxSeq<Tup>{})) { + return ApplyFromTupleImpl(f, tup, TupIdxSeq<Tup>{}); +} + +template <typename T> +std::string Fmt(const T& x) { + std::ostringstream os; + os << x; + return os.str(); +} + +struct PoorStrCat { + template <typename... Args> + std::string operator()(const Args&... args) const { + std::string r; + for (const auto& e : {Fmt(args)...}) r += e; + return r; + } +}; + +template <typename Tup, size_t... Is> +std::vector<std::string> TupStringVecImpl(const Tup& tup, + absl::index_sequence<Is...>) { + return {Fmt(std::get<Is>(tup))...}; +} + +template <typename... Ts> +std::vector<std::string> TupStringVec(const std::tuple<Ts...>& tup) { + return TupStringVecImpl(tup, absl::index_sequence_for<Ts...>()); +} + +TEST(MakeIndexSequenceTest, ApplyFromTupleExample) { + PoorStrCat f{}; + EXPECT_EQ("12abc3.14", f(12, "abc", 3.14)); + EXPECT_EQ("12abc3.14", ApplyFromTuple(f, std::make_tuple(12, "abc", 3.14))); +} + +TEST(IndexSequenceForTest, Basic) { + StaticAssertTypeEq<absl::index_sequence<>, absl::index_sequence_for<>>(); + StaticAssertTypeEq<absl::index_sequence<0>, absl::index_sequence_for<int>>(); + StaticAssertTypeEq<absl::index_sequence<0, 1, 2, 3>, + absl::index_sequence_for<int, void, char, int>>(); +} + +TEST(IndexSequenceForTest, Example) { + EXPECT_THAT(TupStringVec(std::make_tuple(12, "abc", 3.14)), + ElementsAre("12", "abc", "3.14")); +} + +int Function(int a, int b) { return a - b; } + +int Sink(std::unique_ptr<int> p) { return *p; } + +std::unique_ptr<int> Factory(int n) { return absl::make_unique<int>(n); } + +void NoOp() {} + +struct ConstFunctor { + int operator()(int a, int b) const { return a - b; } +}; + +struct MutableFunctor { + int operator()(int a, int b) { return a - b; } +}; + +struct EphemeralFunctor { + EphemeralFunctor() {} + EphemeralFunctor(const EphemeralFunctor&) {} + EphemeralFunctor(EphemeralFunctor&&) {} + int operator()(int a, int b) && { return a - b; } +}; + +struct OverloadedFunctor { + OverloadedFunctor() {} + OverloadedFunctor(const OverloadedFunctor&) {} + OverloadedFunctor(OverloadedFunctor&&) {} + template <typename... Args> + std::string operator()(const Args&... args) & { + return absl::StrCat("&", args...); + } + template <typename... Args> + std::string operator()(const Args&... args) const& { + return absl::StrCat("const&", args...); + } + template <typename... Args> + std::string operator()(const Args&... args) && { + return absl::StrCat("&&", args...); + } +}; + +struct Class { + int Method(int a, int b) { return a - b; } + int ConstMethod(int a, int b) const { return a - b; } + + int member; +}; + +struct FlipFlop { + int ConstMethod() const { return member; } + FlipFlop operator*() const { return {-member}; } + + int member; +}; + +TEST(ApplyTest, Function) { + EXPECT_EQ(1, absl::apply(Function, std::make_tuple(3, 2))); + EXPECT_EQ(1, absl::apply(&Function, std::make_tuple(3, 2))); +} + +TEST(ApplyTest, NonCopyableArgument) { + EXPECT_EQ(42, absl::apply(Sink, std::make_tuple(absl::make_unique<int>(42)))); +} + +TEST(ApplyTest, NonCopyableResult) { + EXPECT_THAT(absl::apply(Factory, std::make_tuple(42)), + ::testing::Pointee(42)); +} + +TEST(ApplyTest, VoidResult) { absl::apply(NoOp, std::tuple<>()); } + +TEST(ApplyTest, ConstFunctor) { + EXPECT_EQ(1, absl::apply(ConstFunctor(), std::make_tuple(3, 2))); +} + +TEST(ApplyTest, MutableFunctor) { + MutableFunctor f; + EXPECT_EQ(1, absl::apply(f, std::make_tuple(3, 2))); + EXPECT_EQ(1, absl::apply(MutableFunctor(), std::make_tuple(3, 2))); +} +TEST(ApplyTest, EphemeralFunctor) { + EphemeralFunctor f; + EXPECT_EQ(1, absl::apply(std::move(f), std::make_tuple(3, 2))); + EXPECT_EQ(1, absl::apply(EphemeralFunctor(), std::make_tuple(3, 2))); +} +TEST(ApplyTest, OverloadedFunctor) { + OverloadedFunctor f; + const OverloadedFunctor& cf = f; + + EXPECT_EQ("&", absl::apply(f, std::tuple<>{})); + EXPECT_EQ("& 42", absl::apply(f, std::make_tuple(" 42"))); + + EXPECT_EQ("const&", absl::apply(cf, std::tuple<>{})); + EXPECT_EQ("const& 42", absl::apply(cf, std::make_tuple(" 42"))); + + EXPECT_EQ("&&", absl::apply(std::move(f), std::tuple<>{})); + OverloadedFunctor f2; + EXPECT_EQ("&& 42", absl::apply(std::move(f2), std::make_tuple(" 42"))); +} + +TEST(ApplyTest, ReferenceWrapper) { + ConstFunctor cf; + MutableFunctor mf; + EXPECT_EQ(1, absl::apply(std::cref(cf), std::make_tuple(3, 2))); + EXPECT_EQ(1, absl::apply(std::ref(cf), std::make_tuple(3, 2))); + EXPECT_EQ(1, absl::apply(std::ref(mf), std::make_tuple(3, 2))); +} + +TEST(ApplyTest, MemberFunction) { + std::unique_ptr<Class> p(new Class); + std::unique_ptr<const Class> cp(new Class); + EXPECT_EQ( + 1, absl::apply(&Class::Method, + std::tuple<std::unique_ptr<Class>&, int, int>(p, 3, 2))); + EXPECT_EQ(1, absl::apply(&Class::Method, + std::tuple<Class*, int, int>(p.get(), 3, 2))); + EXPECT_EQ( + 1, absl::apply(&Class::Method, std::tuple<Class&, int, int>(*p, 3, 2))); + + EXPECT_EQ( + 1, absl::apply(&Class::ConstMethod, + std::tuple<std::unique_ptr<Class>&, int, int>(p, 3, 2))); + EXPECT_EQ(1, absl::apply(&Class::ConstMethod, + std::tuple<Class*, int, int>(p.get(), 3, 2))); + EXPECT_EQ(1, absl::apply(&Class::ConstMethod, + std::tuple<Class&, int, int>(*p, 3, 2))); + + EXPECT_EQ(1, absl::apply(&Class::ConstMethod, + std::tuple<std::unique_ptr<const Class>&, int, int>( + cp, 3, 2))); + EXPECT_EQ(1, absl::apply(&Class::ConstMethod, + std::tuple<const Class*, int, int>(cp.get(), 3, 2))); + EXPECT_EQ(1, absl::apply(&Class::ConstMethod, + std::tuple<const Class&, int, int>(*cp, 3, 2))); + + EXPECT_EQ(1, absl::apply(&Class::Method, + std::make_tuple(absl::make_unique<Class>(), 3, 2))); + EXPECT_EQ(1, absl::apply(&Class::ConstMethod, + std::make_tuple(absl::make_unique<Class>(), 3, 2))); + EXPECT_EQ( + 1, absl::apply(&Class::ConstMethod, + std::make_tuple(absl::make_unique<const Class>(), 3, 2))); +} + +TEST(ApplyTest, DataMember) { + std::unique_ptr<Class> p(new Class{42}); + std::unique_ptr<const Class> cp(new Class{42}); + EXPECT_EQ( + 42, absl::apply(&Class::member, std::tuple<std::unique_ptr<Class>&>(p))); + EXPECT_EQ(42, absl::apply(&Class::member, std::tuple<Class&>(*p))); + EXPECT_EQ(42, absl::apply(&Class::member, std::tuple<Class*>(p.get()))); + + absl::apply(&Class::member, std::tuple<std::unique_ptr<Class>&>(p)) = 42; + absl::apply(&Class::member, std::tuple<Class*>(p.get())) = 42; + absl::apply(&Class::member, std::tuple<Class&>(*p)) = 42; + + EXPECT_EQ(42, absl::apply(&Class::member, + std::tuple<std::unique_ptr<const Class>&>(cp))); + EXPECT_EQ(42, absl::apply(&Class::member, std::tuple<const Class&>(*cp))); + EXPECT_EQ(42, + absl::apply(&Class::member, std::tuple<const Class*>(cp.get()))); +} + +TEST(ApplyTest, FlipFlop) { + FlipFlop obj = {42}; + // This call could resolve to (obj.*&FlipFlop::ConstMethod)() or + // ((*obj).*&FlipFlop::ConstMethod)(). We verify that it's the former. + EXPECT_EQ(42, absl::apply(&FlipFlop::ConstMethod, std::make_tuple(obj))); + EXPECT_EQ(42, absl::apply(&FlipFlop::member, std::make_tuple(obj))); +} + +TEST(ExchangeTest, MoveOnly) { + auto a = Factory(1); + EXPECT_EQ(1, *a); + auto b = absl::exchange(a, Factory(2)); + EXPECT_EQ(2, *a); + EXPECT_EQ(1, *b); +} + +TEST(MakeFromTupleTest, String) { + EXPECT_EQ( + absl::make_from_tuple<std::string>(std::make_tuple("hello world", 5)), + "hello"); +} + +TEST(MakeFromTupleTest, MoveOnlyParameter) { + struct S { + S(std::unique_ptr<int> n, std::unique_ptr<int> m) : value(*n + *m) {} + int value = 0; + }; + auto tup = + std::make_tuple(absl::make_unique<int>(3), absl::make_unique<int>(4)); + auto s = absl::make_from_tuple<S>(std::move(tup)); + EXPECT_EQ(s.value, 7); +} + +TEST(MakeFromTupleTest, NoParameters) { + struct S { + S() : value(1) {} + int value = 2; + }; + EXPECT_EQ(absl::make_from_tuple<S>(std::make_tuple()).value, 1); +} + +TEST(MakeFromTupleTest, Pair) { + EXPECT_EQ( + (absl::make_from_tuple<std::pair<bool, int>>(std::make_tuple(true, 17))), + std::make_pair(true, 17)); +} + +} // namespace + |