| // 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 |
| // |
| // http://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/base/internal/invoke.h" |
| |
| #include <functional> |
| #include <memory> |
| #include <string> |
| #include <utility> |
| |
| #include "gmock/gmock.h" |
| #include "gtest/gtest.h" |
| #include "absl/memory/memory.h" |
| #include "absl/strings/str_cat.h" |
| |
| namespace absl { |
| inline namespace lts_2018_12_18 { |
| namespace base_internal { |
| namespace { |
| |
| 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 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 { |
| int operator()(int a, int b) && { return a - b; } |
| }; |
| |
| struct OverloadedFunctor { |
| template <typename... Args> |
| std::string operator()(const Args&... args) & { |
| return StrCat("&", args...); |
| } |
| template <typename... Args> |
| std::string operator()(const Args&... args) const& { |
| return StrCat("const&", args...); |
| } |
| template <typename... Args> |
| std::string operator()(const Args&... args) && { |
| return 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; |
| }; |
| |
| // CallMaybeWithArg(f) resolves either to Invoke(f) or Invoke(f, 42), depending |
| // on which one is valid. |
| template <typename F> |
| decltype(Invoke(std::declval<const F&>())) CallMaybeWithArg(const F& f) { |
| return Invoke(f); |
| } |
| |
| template <typename F> |
| decltype(Invoke(std::declval<const F&>(), 42)) CallMaybeWithArg(const F& f) { |
| return Invoke(f, 42); |
| } |
| |
| TEST(InvokeTest, Function) { |
| EXPECT_EQ(1, Invoke(Function, 3, 2)); |
| EXPECT_EQ(1, Invoke(&Function, 3, 2)); |
| } |
| |
| TEST(InvokeTest, NonCopyableArgument) { |
| EXPECT_EQ(42, Invoke(Sink, make_unique<int>(42))); |
| } |
| |
| TEST(InvokeTest, NonCopyableResult) { |
| EXPECT_THAT(Invoke(Factory, 42), ::testing::Pointee(42)); |
| } |
| |
| TEST(InvokeTest, VoidResult) { |
| Invoke(NoOp); |
| } |
| |
| TEST(InvokeTest, ConstFunctor) { |
| EXPECT_EQ(1, Invoke(ConstFunctor(), 3, 2)); |
| } |
| |
| TEST(InvokeTest, MutableFunctor) { |
| MutableFunctor f; |
| EXPECT_EQ(1, Invoke(f, 3, 2)); |
| EXPECT_EQ(1, Invoke(MutableFunctor(), 3, 2)); |
| } |
| |
| TEST(InvokeTest, EphemeralFunctor) { |
| EphemeralFunctor f; |
| EXPECT_EQ(1, Invoke(std::move(f), 3, 2)); |
| EXPECT_EQ(1, Invoke(EphemeralFunctor(), 3, 2)); |
| } |
| |
| TEST(InvokeTest, OverloadedFunctor) { |
| OverloadedFunctor f; |
| const OverloadedFunctor& cf = f; |
| |
| EXPECT_EQ("&", Invoke(f)); |
| EXPECT_EQ("& 42", Invoke(f, " 42")); |
| |
| EXPECT_EQ("const&", Invoke(cf)); |
| EXPECT_EQ("const& 42", Invoke(cf, " 42")); |
| |
| EXPECT_EQ("&&", Invoke(std::move(f))); |
| EXPECT_EQ("&& 42", Invoke(std::move(f), " 42")); |
| } |
| |
| TEST(InvokeTest, ReferenceWrapper) { |
| ConstFunctor cf; |
| MutableFunctor mf; |
| EXPECT_EQ(1, Invoke(std::cref(cf), 3, 2)); |
| EXPECT_EQ(1, Invoke(std::ref(cf), 3, 2)); |
| EXPECT_EQ(1, Invoke(std::ref(mf), 3, 2)); |
| } |
| |
| TEST(InvokeTest, MemberFunction) { |
| std::unique_ptr<Class> p(new Class); |
| std::unique_ptr<const Class> cp(new Class); |
| EXPECT_EQ(1, Invoke(&Class::Method, p, 3, 2)); |
| EXPECT_EQ(1, Invoke(&Class::Method, p.get(), 3, 2)); |
| |
| EXPECT_EQ(1, Invoke(&Class::ConstMethod, p, 3, 2)); |
| EXPECT_EQ(1, Invoke(&Class::ConstMethod, p.get(), 3, 2)); |
| EXPECT_EQ(1, Invoke(&Class::ConstMethod, *p, 3, 2)); |
| |
| EXPECT_EQ(1, Invoke(&Class::ConstMethod, cp, 3, 2)); |
| EXPECT_EQ(1, Invoke(&Class::ConstMethod, cp.get(), 3, 2)); |
| EXPECT_EQ(1, Invoke(&Class::ConstMethod, *cp, 3, 2)); |
| |
| EXPECT_EQ(1, Invoke(&Class::Method, make_unique<Class>(), 3, 2)); |
| EXPECT_EQ(1, Invoke(&Class::ConstMethod, make_unique<Class>(), 3, 2)); |
| EXPECT_EQ(1, Invoke(&Class::ConstMethod, make_unique<const Class>(), 3, 2)); |
| } |
| |
| TEST(InvokeTest, DataMember) { |
| std::unique_ptr<Class> p(new Class{42}); |
| std::unique_ptr<const Class> cp(new Class{42}); |
| EXPECT_EQ(42, Invoke(&Class::member, p)); |
| EXPECT_EQ(42, Invoke(&Class::member, *p)); |
| EXPECT_EQ(42, Invoke(&Class::member, p.get())); |
| |
| Invoke(&Class::member, p) = 42; |
| Invoke(&Class::member, p.get()) = 42; |
| |
| EXPECT_EQ(42, Invoke(&Class::member, cp)); |
| EXPECT_EQ(42, Invoke(&Class::member, *cp)); |
| EXPECT_EQ(42, Invoke(&Class::member, cp.get())); |
| } |
| |
| TEST(InvokeTest, 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, Invoke(&FlipFlop::ConstMethod, obj)); |
| EXPECT_EQ(42, Invoke(&FlipFlop::member, obj)); |
| } |
| |
| TEST(InvokeTest, SfinaeFriendly) { |
| CallMaybeWithArg(NoOp); |
| EXPECT_THAT(CallMaybeWithArg(Factory), ::testing::Pointee(42)); |
| } |
| |
| } // namespace |
| } // namespace base_internal |
| } // inline namespace lts_2018_12_18 |
| } // namespace absl |