From 48cd2c3f351ff188bc85684b84a91b6e6d17d896 Mon Sep 17 00:00:00 2001 From: Abseil Team Date: Thu, 27 Sep 2018 12:24:54 -0700 Subject: Export of internal Abseil changes. -- 4eacae3ff1b14b1d309e8092185bc10e8a6203cf by Derek Mauro : Release SwissTable - a fast, efficient, cache-friendly hash table. https://www.youtube.com/watch?v=ncHmEUmJZf4 PiperOrigin-RevId: 214816527 -- df8c3dfab3cfb2f4365909a84d0683b193cfbb11 by Derek Mauro : Internal change PiperOrigin-RevId: 214785288 -- 1eabd5266bbcebc33eecc91e5309b751856a75c8 by Abseil Team : Internal change PiperOrigin-RevId: 214722931 -- 2ebbfac950f83146b46253038e7dd7dcde9f2951 by Derek Mauro : Internal change PiperOrigin-RevId: 214701684 GitOrigin-RevId: 4eacae3ff1b14b1d309e8092185bc10e8a6203cf Change-Id: I9ba64e395b22ad7863213d157b8019b082adc19d --- .../internal/hash_function_defaults_test.cc | 299 +++++++++++++++++++++ 1 file changed, 299 insertions(+) create mode 100644 absl/container/internal/hash_function_defaults_test.cc (limited to 'absl/container/internal/hash_function_defaults_test.cc') diff --git a/absl/container/internal/hash_function_defaults_test.cc b/absl/container/internal/hash_function_defaults_test.cc new file mode 100644 index 0000000..464baae --- /dev/null +++ b/absl/container/internal/hash_function_defaults_test.cc @@ -0,0 +1,299 @@ +// 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 +// +// 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/container/internal/hash_function_defaults.h" + +#include +#include +#include + +#include "gtest/gtest.h" +#include "absl/strings/string_view.h" + +namespace absl { +namespace container_internal { +namespace { + +using ::testing::Types; + +TEST(Eq, Int32) { + hash_default_eq eq; + EXPECT_TRUE(eq(1, 1u)); + EXPECT_TRUE(eq(1, char{1})); + EXPECT_TRUE(eq(1, true)); + EXPECT_TRUE(eq(1, double{1.1})); + EXPECT_FALSE(eq(1, char{2})); + EXPECT_FALSE(eq(1, 2u)); + EXPECT_FALSE(eq(1, false)); + EXPECT_FALSE(eq(1, 2.)); +} + +TEST(Hash, Int32) { + hash_default_hash hash; + auto h = hash(1); + EXPECT_EQ(h, hash(1u)); + EXPECT_EQ(h, hash(char{1})); + EXPECT_EQ(h, hash(true)); + EXPECT_EQ(h, hash(double{1.1})); + EXPECT_NE(h, hash(2u)); + EXPECT_NE(h, hash(char{2})); + EXPECT_NE(h, hash(false)); + EXPECT_NE(h, hash(2.)); +} + +enum class MyEnum { A, B, C, D }; + +TEST(Eq, Enum) { + hash_default_eq eq; + EXPECT_TRUE(eq(MyEnum::A, MyEnum::A)); + EXPECT_FALSE(eq(MyEnum::A, MyEnum::B)); +} + +TEST(Hash, Enum) { + hash_default_hash hash; + + for (MyEnum e : {MyEnum::A, MyEnum::B, MyEnum::C}) { + auto h = hash(e); + EXPECT_EQ(h, hash_default_hash{}(static_cast(e))); + EXPECT_NE(h, hash(MyEnum::D)); + } +} + +using StringTypes = ::testing::Types; + +template +struct EqString : ::testing::Test { + hash_default_eq key_eq; +}; + +TYPED_TEST_CASE(EqString, StringTypes); + +template +struct HashString : ::testing::Test { + hash_default_hash hasher; +}; + +TYPED_TEST_CASE(HashString, StringTypes); + +TYPED_TEST(EqString, Works) { + auto eq = this->key_eq; + EXPECT_TRUE(eq("a", "a")); + EXPECT_TRUE(eq("a", absl::string_view("a"))); + EXPECT_TRUE(eq("a", std::string("a"))); + EXPECT_FALSE(eq("a", "b")); + EXPECT_FALSE(eq("a", absl::string_view("b"))); + EXPECT_FALSE(eq("a", std::string("b"))); +} + +TYPED_TEST(HashString, Works) { + auto hash = this->hasher; + auto h = hash("a"); + EXPECT_EQ(h, hash(absl::string_view("a"))); + EXPECT_EQ(h, hash(std::string("a"))); + EXPECT_NE(h, hash(absl::string_view("b"))); + EXPECT_NE(h, hash(std::string("b"))); +} + +struct NoDeleter { + template + void operator()(const T* ptr) const {} +}; + +using PointerTypes = + ::testing::Types, + std::unique_ptr, + std::unique_ptr, std::unique_ptr, + std::shared_ptr, std::shared_ptr>; + +template +struct EqPointer : ::testing::Test { + hash_default_eq key_eq; +}; + +TYPED_TEST_CASE(EqPointer, PointerTypes); + +template +struct HashPointer : ::testing::Test { + hash_default_hash hasher; +}; + +TYPED_TEST_CASE(HashPointer, PointerTypes); + +TYPED_TEST(EqPointer, Works) { + int dummy; + auto eq = this->key_eq; + auto sptr = std::make_shared(); + std::shared_ptr csptr = sptr; + int* ptr = sptr.get(); + const int* cptr = ptr; + std::unique_ptr uptr(ptr); + std::unique_ptr cuptr(ptr); + + EXPECT_TRUE(eq(ptr, cptr)); + EXPECT_TRUE(eq(ptr, sptr)); + EXPECT_TRUE(eq(ptr, uptr)); + EXPECT_TRUE(eq(ptr, csptr)); + EXPECT_TRUE(eq(ptr, cuptr)); + EXPECT_FALSE(eq(&dummy, cptr)); + EXPECT_FALSE(eq(&dummy, sptr)); + EXPECT_FALSE(eq(&dummy, uptr)); + EXPECT_FALSE(eq(&dummy, csptr)); + EXPECT_FALSE(eq(&dummy, cuptr)); +} + +TEST(Hash, DerivedAndBase) { + struct Base {}; + struct Derived : Base {}; + + hash_default_hash hasher; + + Base base; + Derived derived; + EXPECT_NE(hasher(&base), hasher(&derived)); + EXPECT_EQ(hasher(static_cast(&derived)), hasher(&derived)); + + auto dp = std::make_shared(); + EXPECT_EQ(hasher(static_cast(dp.get())), hasher(dp)); +} + +TEST(Hash, FunctionPointer) { + using Func = int (*)(); + hash_default_hash hasher; + hash_default_eq eq; + + Func p1 = [] { return 1; }, p2 = [] { return 2; }; + EXPECT_EQ(hasher(p1), hasher(p1)); + EXPECT_TRUE(eq(p1, p1)); + + EXPECT_NE(hasher(p1), hasher(p2)); + EXPECT_FALSE(eq(p1, p2)); +} + +TYPED_TEST(HashPointer, Works) { + int dummy; + auto hash = this->hasher; + auto sptr = std::make_shared(); + std::shared_ptr csptr = sptr; + int* ptr = sptr.get(); + const int* cptr = ptr; + std::unique_ptr uptr(ptr); + std::unique_ptr cuptr(ptr); + + EXPECT_EQ(hash(ptr), hash(cptr)); + EXPECT_EQ(hash(ptr), hash(sptr)); + EXPECT_EQ(hash(ptr), hash(uptr)); + EXPECT_EQ(hash(ptr), hash(csptr)); + EXPECT_EQ(hash(ptr), hash(cuptr)); + EXPECT_NE(hash(&dummy), hash(cptr)); + EXPECT_NE(hash(&dummy), hash(sptr)); + EXPECT_NE(hash(&dummy), hash(uptr)); + EXPECT_NE(hash(&dummy), hash(csptr)); + EXPECT_NE(hash(&dummy), hash(cuptr)); +} + +// Cartesian product of (string, std::string, absl::string_view) +// with (string, std::string, absl::string_view, const char*). +using StringTypesCartesianProduct = Types< + // clang-format off + + std::pair, + std::pair, + std::pair, + + std::pair, + std::pair, + std::pair>; +// clang-format on + +constexpr char kFirstString[] = "abc123"; +constexpr char kSecondString[] = "ijk456"; + +template +struct StringLikeTest : public ::testing::Test { + typename T::first_type a1{kFirstString}; + typename T::second_type b1{kFirstString}; + typename T::first_type a2{kSecondString}; + typename T::second_type b2{kSecondString}; + hash_default_eq eq; + hash_default_hash hash; +}; + +TYPED_TEST_CASE_P(StringLikeTest); + +TYPED_TEST_P(StringLikeTest, Eq) { + EXPECT_TRUE(this->eq(this->a1, this->b1)); + EXPECT_TRUE(this->eq(this->b1, this->a1)); +} + +TYPED_TEST_P(StringLikeTest, NotEq) { + EXPECT_FALSE(this->eq(this->a1, this->b2)); + EXPECT_FALSE(this->eq(this->b2, this->a1)); +} + +TYPED_TEST_P(StringLikeTest, HashEq) { + EXPECT_EQ(this->hash(this->a1), this->hash(this->b1)); + EXPECT_EQ(this->hash(this->a2), this->hash(this->b2)); + // It would be a poor hash function which collides on these strings. + EXPECT_NE(this->hash(this->a1), this->hash(this->b2)); +} + +TYPED_TEST_CASE(StringLikeTest, StringTypesCartesianProduct); + +} // namespace +} // namespace container_internal +} // namespace absl + +enum Hash : size_t { + kStd = 0x2, // std::hash +#ifdef _MSC_VER + kExtension = kStd, // In MSVC, std::hash == ::hash +#else // _MSC_VER + kExtension = 0x4, // ::hash (GCC extension) +#endif // _MSC_VER +}; + +// H is a bitmask of Hash enumerations. +// Hashable is hashable via all means specified in H. +template +struct Hashable { + static constexpr bool HashableBy(Hash h) { return h & H; } +}; + +namespace std { +template +struct hash> { + template , + class = typename std::enable_if::type> + size_t operator()(E) const { + return kStd; + } +}; +} // namespace std + +namespace absl { +namespace container_internal { +namespace { + +template +size_t Hash(const T& v) { + return hash_default_hash()(v); +} + +TEST(Delegate, HashDispatch) { + EXPECT_EQ(Hash(kStd), Hash(Hashable())); +} + +} // namespace +} // namespace container_internal +} // namespace absl -- cgit v1.2.3