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Diffstat (limited to 'third_party/abseil_cpp/absl/base/internal/exception_safety_testing.h')
| -rw-r--r-- | third_party/abseil_cpp/absl/base/internal/exception_safety_testing.h | 1101 |
1 files changed, 0 insertions, 1101 deletions
diff --git a/third_party/abseil_cpp/absl/base/internal/exception_safety_testing.h b/third_party/abseil_cpp/absl/base/internal/exception_safety_testing.h deleted file mode 100644 index 6ba89d05df..0000000000 --- a/third_party/abseil_cpp/absl/base/internal/exception_safety_testing.h +++ /dev/null @@ -1,1101 +0,0 @@ -// 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. - -// Utilities for testing exception-safety - -#ifndef ABSL_BASE_INTERNAL_EXCEPTION_SAFETY_TESTING_H_ -#define ABSL_BASE_INTERNAL_EXCEPTION_SAFETY_TESTING_H_ - -#include "absl/base/config.h" - -#ifdef ABSL_HAVE_EXCEPTIONS - -#include <cstddef> -#include <cstdint> -#include <functional> -#include <initializer_list> -#include <iosfwd> -#include <string> -#include <tuple> -#include <unordered_map> - -#include "gtest/gtest.h" -#include "absl/base/internal/pretty_function.h" -#include "absl/memory/memory.h" -#include "absl/meta/type_traits.h" -#include "absl/strings/string_view.h" -#include "absl/strings/substitute.h" -#include "absl/utility/utility.h" - -namespace testing { - -enum class TypeSpec; -enum class AllocSpec; - -constexpr TypeSpec operator|(TypeSpec a, TypeSpec b) { - using T = absl::underlying_type_t<TypeSpec>; - return static_cast<TypeSpec>(static_cast<T>(a) | static_cast<T>(b)); -} - -constexpr TypeSpec operator&(TypeSpec a, TypeSpec b) { - using T = absl::underlying_type_t<TypeSpec>; - return static_cast<TypeSpec>(static_cast<T>(a) & static_cast<T>(b)); -} - -constexpr AllocSpec operator|(AllocSpec a, AllocSpec b) { - using T = absl::underlying_type_t<AllocSpec>; - return static_cast<AllocSpec>(static_cast<T>(a) | static_cast<T>(b)); -} - -constexpr AllocSpec operator&(AllocSpec a, AllocSpec b) { - using T = absl::underlying_type_t<AllocSpec>; - return static_cast<AllocSpec>(static_cast<T>(a) & static_cast<T>(b)); -} - -namespace exceptions_internal { - -std::string GetSpecString(TypeSpec); -std::string GetSpecString(AllocSpec); - -struct NoThrowTag {}; -struct StrongGuaranteeTagType {}; - -// A simple exception class. We throw this so that test code can catch -// exceptions specifically thrown by ThrowingValue. -class TestException { - public: - explicit TestException(absl::string_view msg) : msg_(msg) {} - virtual ~TestException() {} - virtual const char* what() const noexcept { return msg_.c_str(); } - - private: - std::string msg_; -}; - -// TestBadAllocException exists because allocation functions must throw an -// exception which can be caught by a handler of std::bad_alloc. We use a child -// class of std::bad_alloc so we can customise the error message, and also -// derive from TestException so we don't accidentally end up catching an actual -// bad_alloc exception in TestExceptionSafety. -class TestBadAllocException : public std::bad_alloc, public TestException { - public: - explicit TestBadAllocException(absl::string_view msg) : TestException(msg) {} - using TestException::what; -}; - -extern int countdown; - -// Allows the countdown variable to be set manually (defaulting to the initial -// value of 0) -inline void SetCountdown(int i = 0) { countdown = i; } -// Sets the countdown to the terminal value -1 -inline void UnsetCountdown() { SetCountdown(-1); } - -void MaybeThrow(absl::string_view msg, bool throw_bad_alloc = false); - -testing::AssertionResult FailureMessage(const TestException& e, - int countdown) noexcept; - -struct TrackedAddress { - bool is_alive; - std::string description; -}; - -// Inspects the constructions and destructions of anything inheriting from -// TrackedObject. This allows us to safely "leak" TrackedObjects, as -// ConstructorTracker will destroy everything left over in its destructor. -class ConstructorTracker { - public: - explicit ConstructorTracker(int count) : countdown_(count) { - assert(current_tracker_instance_ == nullptr); - current_tracker_instance_ = this; - } - - ~ConstructorTracker() { - assert(current_tracker_instance_ == this); - current_tracker_instance_ = nullptr; - - for (auto& it : address_map_) { - void* address = it.first; - TrackedAddress& tracked_address = it.second; - if (tracked_address.is_alive) { - ADD_FAILURE() << ErrorMessage(address, tracked_address.description, - countdown_, "Object was not destroyed."); - } - } - } - - static void ObjectConstructed(void* address, std::string description) { - if (!CurrentlyTracking()) return; - - TrackedAddress& tracked_address = - current_tracker_instance_->address_map_[address]; - if (tracked_address.is_alive) { - ADD_FAILURE() << ErrorMessage( - address, tracked_address.description, - current_tracker_instance_->countdown_, - "Object was re-constructed. Current object was constructed by " + - description); - } - tracked_address = {true, std::move(description)}; - } - - static void ObjectDestructed(void* address) { - if (!CurrentlyTracking()) return; - - auto it = current_tracker_instance_->address_map_.find(address); - // Not tracked. Ignore. - if (it == current_tracker_instance_->address_map_.end()) return; - - TrackedAddress& tracked_address = it->second; - if (!tracked_address.is_alive) { - ADD_FAILURE() << ErrorMessage(address, tracked_address.description, - current_tracker_instance_->countdown_, - "Object was re-destroyed."); - } - tracked_address.is_alive = false; - } - - private: - static bool CurrentlyTracking() { - return current_tracker_instance_ != nullptr; - } - - static std::string ErrorMessage(void* address, - const std::string& address_description, - int countdown, - const std::string& error_description) { - return absl::Substitute( - "With coundtown at $0:\n" - " $1\n" - " Object originally constructed by $2\n" - " Object address: $3\n", - countdown, error_description, address_description, address); - } - - std::unordered_map<void*, TrackedAddress> address_map_; - int countdown_; - - static ConstructorTracker* current_tracker_instance_; -}; - -class TrackedObject { - public: - TrackedObject(const TrackedObject&) = delete; - TrackedObject(TrackedObject&&) = delete; - - protected: - explicit TrackedObject(std::string description) { - ConstructorTracker::ObjectConstructed(this, std::move(description)); - } - - ~TrackedObject() noexcept { ConstructorTracker::ObjectDestructed(this); } -}; -} // namespace exceptions_internal - -extern exceptions_internal::NoThrowTag nothrow_ctor; - -extern exceptions_internal::StrongGuaranteeTagType strong_guarantee; - -// A test class which is convertible to bool. The conversion can be -// instrumented to throw at a controlled time. -class ThrowingBool { - public: - ThrowingBool(bool b) noexcept : b_(b) {} // NOLINT(runtime/explicit) - operator bool() const { // NOLINT - exceptions_internal::MaybeThrow(ABSL_PRETTY_FUNCTION); - return b_; - } - - private: - bool b_; -}; - -/* - * Configuration enum for the ThrowingValue type that defines behavior for the - * lifetime of the instance. Use testing::nothrow_ctor to prevent the integer - * constructor from throwing. - * - * kEverythingThrows: Every operation can throw an exception - * kNoThrowCopy: Copy construction and copy assignment will not throw - * kNoThrowMove: Move construction and move assignment will not throw - * kNoThrowNew: Overloaded operators new and new[] will not throw - */ -enum class TypeSpec { - kEverythingThrows = 0, - kNoThrowCopy = 1, - kNoThrowMove = 1 << 1, - kNoThrowNew = 1 << 2, -}; - -/* - * A testing class instrumented to throw an exception at a controlled time. - * - * ThrowingValue implements a slightly relaxed version of the Regular concept -- - * that is it's a value type with the expected semantics. It also implements - * arithmetic operations. It doesn't implement member and pointer operators - * like operator-> or operator[]. - * - * ThrowingValue can be instrumented to have certain operations be noexcept by - * using compile-time bitfield template arguments. That is, to make an - * ThrowingValue which has noexcept move construction/assignment and noexcept - * copy construction/assignment, use the following: - * ThrowingValue<testing::kNoThrowMove | testing::kNoThrowCopy> my_thrwr{val}; - */ -template <TypeSpec Spec = TypeSpec::kEverythingThrows> -class ThrowingValue : private exceptions_internal::TrackedObject { - static constexpr bool IsSpecified(TypeSpec spec) { - return static_cast<bool>(Spec & spec); - } - - static constexpr int kDefaultValue = 0; - static constexpr int kBadValue = 938550620; - - public: - ThrowingValue() : TrackedObject(GetInstanceString(kDefaultValue)) { - exceptions_internal::MaybeThrow(ABSL_PRETTY_FUNCTION); - dummy_ = kDefaultValue; - } - - ThrowingValue(const ThrowingValue& other) noexcept( - IsSpecified(TypeSpec::kNoThrowCopy)) - : TrackedObject(GetInstanceString(other.dummy_)) { - if (!IsSpecified(TypeSpec::kNoThrowCopy)) { - exceptions_internal::MaybeThrow(ABSL_PRETTY_FUNCTION); - } - dummy_ = other.dummy_; - } - - ThrowingValue(ThrowingValue&& other) noexcept( - IsSpecified(TypeSpec::kNoThrowMove)) - : TrackedObject(GetInstanceString(other.dummy_)) { - if (!IsSpecified(TypeSpec::kNoThrowMove)) { - exceptions_internal::MaybeThrow(ABSL_PRETTY_FUNCTION); - } - dummy_ = other.dummy_; - } - - explicit ThrowingValue(int i) : TrackedObject(GetInstanceString(i)) { - exceptions_internal::MaybeThrow(ABSL_PRETTY_FUNCTION); - dummy_ = i; - } - - ThrowingValue(int i, exceptions_internal::NoThrowTag) noexcept - : TrackedObject(GetInstanceString(i)), dummy_(i) {} - - // absl expects nothrow destructors - ~ThrowingValue() noexcept = default; - - ThrowingValue& operator=(const ThrowingValue& other) noexcept( - IsSpecified(TypeSpec::kNoThrowCopy)) { - dummy_ = kBadValue; - if (!IsSpecified(TypeSpec::kNoThrowCopy)) { - exceptions_internal::MaybeThrow(ABSL_PRETTY_FUNCTION); - } - dummy_ = other.dummy_; - return *this; - } - - ThrowingValue& operator=(ThrowingValue&& other) noexcept( - IsSpecified(TypeSpec::kNoThrowMove)) { - dummy_ = kBadValue; - if (!IsSpecified(TypeSpec::kNoThrowMove)) { - exceptions_internal::MaybeThrow(ABSL_PRETTY_FUNCTION); - } - dummy_ = other.dummy_; - return *this; - } - - // Arithmetic Operators - ThrowingValue operator+(const ThrowingValue& other) const { - exceptions_internal::MaybeThrow(ABSL_PRETTY_FUNCTION); - return ThrowingValue(dummy_ + other.dummy_, nothrow_ctor); - } - - ThrowingValue operator+() const { - exceptions_internal::MaybeThrow(ABSL_PRETTY_FUNCTION); - return ThrowingValue(dummy_, nothrow_ctor); - } - - ThrowingValue operator-(const ThrowingValue& other) const { - exceptions_internal::MaybeThrow(ABSL_PRETTY_FUNCTION); - return ThrowingValue(dummy_ - other.dummy_, nothrow_ctor); - } - - ThrowingValue operator-() const { - exceptions_internal::MaybeThrow(ABSL_PRETTY_FUNCTION); - return ThrowingValue(-dummy_, nothrow_ctor); - } - - ThrowingValue& operator++() { - exceptions_internal::MaybeThrow(ABSL_PRETTY_FUNCTION); - ++dummy_; - return *this; - } - - ThrowingValue operator++(int) { - exceptions_internal::MaybeThrow(ABSL_PRETTY_FUNCTION); - auto out = ThrowingValue(dummy_, nothrow_ctor); - ++dummy_; - return out; - } - - ThrowingValue& operator--() { - exceptions_internal::MaybeThrow(ABSL_PRETTY_FUNCTION); - --dummy_; - return *this; - } - - ThrowingValue operator--(int) { - exceptions_internal::MaybeThrow(ABSL_PRETTY_FUNCTION); - auto out = ThrowingValue(dummy_, nothrow_ctor); - --dummy_; - return out; - } - - ThrowingValue operator*(const ThrowingValue& other) const { - exceptions_internal::MaybeThrow(ABSL_PRETTY_FUNCTION); - return ThrowingValue(dummy_ * other.dummy_, nothrow_ctor); - } - - ThrowingValue operator/(const ThrowingValue& other) const { - exceptions_internal::MaybeThrow(ABSL_PRETTY_FUNCTION); - return ThrowingValue(dummy_ / other.dummy_, nothrow_ctor); - } - - ThrowingValue operator%(const ThrowingValue& other) const { - exceptions_internal::MaybeThrow(ABSL_PRETTY_FUNCTION); - return ThrowingValue(dummy_ % other.dummy_, nothrow_ctor); - } - - ThrowingValue operator<<(int shift) const { - exceptions_internal::MaybeThrow(ABSL_PRETTY_FUNCTION); - return ThrowingValue(dummy_ << shift, nothrow_ctor); - } - - ThrowingValue operator>>(int shift) const { - exceptions_internal::MaybeThrow(ABSL_PRETTY_FUNCTION); - return ThrowingValue(dummy_ >> shift, nothrow_ctor); - } - - // Comparison Operators - // NOTE: We use `ThrowingBool` instead of `bool` because most STL - // types/containers requires T to be convertible to bool. - friend ThrowingBool operator==(const ThrowingValue& a, - const ThrowingValue& b) { - exceptions_internal::MaybeThrow(ABSL_PRETTY_FUNCTION); - return a.dummy_ == b.dummy_; - } - friend ThrowingBool operator!=(const ThrowingValue& a, - const ThrowingValue& b) { - exceptions_internal::MaybeThrow(ABSL_PRETTY_FUNCTION); - return a.dummy_ != b.dummy_; - } - friend ThrowingBool operator<(const ThrowingValue& a, - const ThrowingValue& b) { - exceptions_internal::MaybeThrow(ABSL_PRETTY_FUNCTION); - return a.dummy_ < b.dummy_; - } - friend ThrowingBool operator<=(const ThrowingValue& a, - const ThrowingValue& b) { - exceptions_internal::MaybeThrow(ABSL_PRETTY_FUNCTION); - return a.dummy_ <= b.dummy_; - } - friend ThrowingBool operator>(const ThrowingValue& a, - const ThrowingValue& b) { - exceptions_internal::MaybeThrow(ABSL_PRETTY_FUNCTION); - return a.dummy_ > b.dummy_; - } - friend ThrowingBool operator>=(const ThrowingValue& a, - const ThrowingValue& b) { - exceptions_internal::MaybeThrow(ABSL_PRETTY_FUNCTION); - return a.dummy_ >= b.dummy_; - } - - // Logical Operators - ThrowingBool operator!() const { - exceptions_internal::MaybeThrow(ABSL_PRETTY_FUNCTION); - return !dummy_; - } - - ThrowingBool operator&&(const ThrowingValue& other) const { - exceptions_internal::MaybeThrow(ABSL_PRETTY_FUNCTION); - return dummy_ && other.dummy_; - } - - ThrowingBool operator||(const ThrowingValue& other) const { - exceptions_internal::MaybeThrow(ABSL_PRETTY_FUNCTION); - return dummy_ || other.dummy_; - } - - // Bitwise Logical Operators - ThrowingValue operator~() const { - exceptions_internal::MaybeThrow(ABSL_PRETTY_FUNCTION); - return ThrowingValue(~dummy_, nothrow_ctor); - } - - ThrowingValue operator&(const ThrowingValue& other) const { - exceptions_internal::MaybeThrow(ABSL_PRETTY_FUNCTION); - return ThrowingValue(dummy_ & other.dummy_, nothrow_ctor); - } - - ThrowingValue operator|(const ThrowingValue& other) const { - exceptions_internal::MaybeThrow(ABSL_PRETTY_FUNCTION); - return ThrowingValue(dummy_ | other.dummy_, nothrow_ctor); - } - - ThrowingValue operator^(const ThrowingValue& other) const { - exceptions_internal::MaybeThrow(ABSL_PRETTY_FUNCTION); - return ThrowingValue(dummy_ ^ other.dummy_, nothrow_ctor); - } - - // Compound Assignment operators - ThrowingValue& operator+=(const ThrowingValue& other) { - exceptions_internal::MaybeThrow(ABSL_PRETTY_FUNCTION); - dummy_ += other.dummy_; - return *this; - } - - ThrowingValue& operator-=(const ThrowingValue& other) { - exceptions_internal::MaybeThrow(ABSL_PRETTY_FUNCTION); - dummy_ -= other.dummy_; - return *this; - } - - ThrowingValue& operator*=(const ThrowingValue& other) { - exceptions_internal::MaybeThrow(ABSL_PRETTY_FUNCTION); - dummy_ *= other.dummy_; - return *this; - } - - ThrowingValue& operator/=(const ThrowingValue& other) { - exceptions_internal::MaybeThrow(ABSL_PRETTY_FUNCTION); - dummy_ /= other.dummy_; - return *this; - } - - ThrowingValue& operator%=(const ThrowingValue& other) { - exceptions_internal::MaybeThrow(ABSL_PRETTY_FUNCTION); - dummy_ %= other.dummy_; - return *this; - } - - ThrowingValue& operator&=(const ThrowingValue& other) { - exceptions_internal::MaybeThrow(ABSL_PRETTY_FUNCTION); - dummy_ &= other.dummy_; - return *this; - } - - ThrowingValue& operator|=(const ThrowingValue& other) { - exceptions_internal::MaybeThrow(ABSL_PRETTY_FUNCTION); - dummy_ |= other.dummy_; - return *this; - } - - ThrowingValue& operator^=(const ThrowingValue& other) { - exceptions_internal::MaybeThrow(ABSL_PRETTY_FUNCTION); - dummy_ ^= other.dummy_; - return *this; - } - - ThrowingValue& operator<<=(int shift) { - exceptions_internal::MaybeThrow(ABSL_PRETTY_FUNCTION); - dummy_ <<= shift; - return *this; - } - - ThrowingValue& operator>>=(int shift) { - exceptions_internal::MaybeThrow(ABSL_PRETTY_FUNCTION); - dummy_ >>= shift; - return *this; - } - - // Pointer operators - void operator&() const = delete; // NOLINT(runtime/operator) - - // Stream operators - friend std::ostream& operator<<(std::ostream& os, const ThrowingValue& tv) { - exceptions_internal::MaybeThrow(ABSL_PRETTY_FUNCTION); - return os << GetInstanceString(tv.dummy_); - } - - friend std::istream& operator>>(std::istream& is, const ThrowingValue&) { - exceptions_internal::MaybeThrow(ABSL_PRETTY_FUNCTION); - return is; - } - - // Memory management operators - // Args.. allows us to overload regular and placement new in one shot - template <typename... Args> - static void* operator new(size_t s, Args&&... args) noexcept( - IsSpecified(TypeSpec::kNoThrowNew)) { - if (!IsSpecified(TypeSpec::kNoThrowNew)) { - exceptions_internal::MaybeThrow(ABSL_PRETTY_FUNCTION, true); - } - return ::operator new(s, std::forward<Args>(args)...); - } - - template <typename... Args> - static void* operator new[](size_t s, Args&&... args) noexcept( - IsSpecified(TypeSpec::kNoThrowNew)) { - if (!IsSpecified(TypeSpec::kNoThrowNew)) { - exceptions_internal::MaybeThrow(ABSL_PRETTY_FUNCTION, true); - } - return ::operator new[](s, std::forward<Args>(args)...); - } - - // Abseil doesn't support throwing overloaded operator delete. These are - // provided so a throwing operator-new can clean up after itself. - // - // We provide both regular and templated operator delete because if only the - // templated version is provided as we did with operator new, the compiler has - // no way of knowing which overload of operator delete to call. See - // https://en.cppreference.com/w/cpp/memory/new/operator_delete and - // https://en.cppreference.com/w/cpp/language/delete for the gory details. - void operator delete(void* p) noexcept { ::operator delete(p); } - - template <typename... Args> - void operator delete(void* p, Args&&... args) noexcept { - ::operator delete(p, std::forward<Args>(args)...); - } - - void operator delete[](void* p) noexcept { return ::operator delete[](p); } - - template <typename... Args> - void operator delete[](void* p, Args&&... args) noexcept { - return ::operator delete[](p, std::forward<Args>(args)...); - } - - // Non-standard access to the actual contained value. No need for this to - // throw. - int& Get() noexcept { return dummy_; } - const int& Get() const noexcept { return dummy_; } - - private: - static std::string GetInstanceString(int dummy) { - return absl::StrCat("ThrowingValue<", - exceptions_internal::GetSpecString(Spec), ">(", dummy, - ")"); - } - - int dummy_; -}; -// While not having to do with exceptions, explicitly delete comma operator, to -// make sure we don't use it on user-supplied types. -template <TypeSpec Spec, typename T> -void operator,(const ThrowingValue<Spec>&, T&&) = delete; -template <TypeSpec Spec, typename T> -void operator,(T&&, const ThrowingValue<Spec>&) = delete; - -/* - * Configuration enum for the ThrowingAllocator type that defines behavior for - * the lifetime of the instance. - * - * kEverythingThrows: Calls to the member functions may throw - * kNoThrowAllocate: Calls to the member functions will not throw - */ -enum class AllocSpec { - kEverythingThrows = 0, - kNoThrowAllocate = 1, -}; - -/* - * An allocator type which is instrumented to throw at a controlled time, or not - * to throw, using AllocSpec. The supported settings are the default of every - * function which is allowed to throw in a conforming allocator possibly - * throwing, or nothing throws, in line with the ABSL_ALLOCATOR_THROWS - * configuration macro. - */ -template <typename T, AllocSpec Spec = AllocSpec::kEverythingThrows> -class ThrowingAllocator : private exceptions_internal::TrackedObject { - static constexpr bool IsSpecified(AllocSpec spec) { - return static_cast<bool>(Spec & spec); - } - - public: - using pointer = T*; - using const_pointer = const T*; - using reference = T&; - using const_reference = const T&; - using void_pointer = void*; - using const_void_pointer = const void*; - using value_type = T; - using size_type = size_t; - using difference_type = ptrdiff_t; - - using is_nothrow = - std::integral_constant<bool, Spec == AllocSpec::kNoThrowAllocate>; - using propagate_on_container_copy_assignment = std::true_type; - using propagate_on_container_move_assignment = std::true_type; - using propagate_on_container_swap = std::true_type; - using is_always_equal = std::false_type; - - ThrowingAllocator() : TrackedObject(GetInstanceString(next_id_)) { - exceptions_internal::MaybeThrow(ABSL_PRETTY_FUNCTION); - dummy_ = std::make_shared<const int>(next_id_++); - } - - template <typename U> - ThrowingAllocator(const ThrowingAllocator<U, Spec>& other) noexcept // NOLINT - : TrackedObject(GetInstanceString(*other.State())), - dummy_(other.State()) {} - - // According to C++11 standard [17.6.3.5], Table 28, the move/copy ctors of - // allocator shall not exit via an exception, thus they are marked noexcept. - ThrowingAllocator(const ThrowingAllocator& other) noexcept - : TrackedObject(GetInstanceString(*other.State())), - dummy_(other.State()) {} - - template <typename U> - ThrowingAllocator(ThrowingAllocator<U, Spec>&& other) noexcept // NOLINT - : TrackedObject(GetInstanceString(*other.State())), - dummy_(std::move(other.State())) {} - - ThrowingAllocator(ThrowingAllocator&& other) noexcept - : TrackedObject(GetInstanceString(*other.State())), - dummy_(std::move(other.State())) {} - - ~ThrowingAllocator() noexcept = default; - - ThrowingAllocator& operator=(const ThrowingAllocator& other) noexcept { - dummy_ = other.State(); - return *this; - } - - template <typename U> - ThrowingAllocator& operator=( - const ThrowingAllocator<U, Spec>& other) noexcept { - dummy_ = other.State(); - return *this; - } - - template <typename U> - ThrowingAllocator& operator=(ThrowingAllocator<U, Spec>&& other) noexcept { - dummy_ = std::move(other.State()); - return *this; - } - - template <typename U> - struct rebind { - using other = ThrowingAllocator<U, Spec>; - }; - - pointer allocate(size_type n) noexcept( - IsSpecified(AllocSpec::kNoThrowAllocate)) { - ReadStateAndMaybeThrow(ABSL_PRETTY_FUNCTION); - return static_cast<pointer>(::operator new(n * sizeof(T))); - } - - pointer allocate(size_type n, const_void_pointer) noexcept( - IsSpecified(AllocSpec::kNoThrowAllocate)) { - return allocate(n); - } - - void deallocate(pointer ptr, size_type) noexcept { - ReadState(); - ::operator delete(static_cast<void*>(ptr)); - } - - template <typename U, typename... Args> - void construct(U* ptr, Args&&... args) noexcept( - IsSpecified(AllocSpec::kNoThrowAllocate)) { - ReadStateAndMaybeThrow(ABSL_PRETTY_FUNCTION); - ::new (static_cast<void*>(ptr)) U(std::forward<Args>(args)...); - } - - template <typename U> - void destroy(U* p) noexcept { - ReadState(); - p->~U(); - } - - size_type max_size() const noexcept { - return (std::numeric_limits<difference_type>::max)() / sizeof(value_type); - } - - ThrowingAllocator select_on_container_copy_construction() noexcept( - IsSpecified(AllocSpec::kNoThrowAllocate)) { - auto& out = *this; - ReadStateAndMaybeThrow(ABSL_PRETTY_FUNCTION); - return out; - } - - template <typename U> - bool operator==(const ThrowingAllocator<U, Spec>& other) const noexcept { - return dummy_ == other.dummy_; - } - - template <typename U> - bool operator!=(const ThrowingAllocator<U, Spec>& other) const noexcept { - return dummy_ != other.dummy_; - } - - template <typename, AllocSpec> - friend class ThrowingAllocator; - - private: - static std::string GetInstanceString(int dummy) { - return absl::StrCat("ThrowingAllocator<", - exceptions_internal::GetSpecString(Spec), ">(", dummy, - ")"); - } - - const std::shared_ptr<const int>& State() const { return dummy_; } - std::shared_ptr<const int>& State() { return dummy_; } - - void ReadState() { - // we know that this will never be true, but the compiler doesn't, so this - // should safely force a read of the value. - if (*dummy_ < 0) std::abort(); - } - - void ReadStateAndMaybeThrow(absl::string_view msg) const { - if (!IsSpecified(AllocSpec::kNoThrowAllocate)) { - exceptions_internal::MaybeThrow( - absl::Substitute("Allocator id $0 threw from $1", *dummy_, msg)); - } - } - - static int next_id_; - std::shared_ptr<const int> dummy_; -}; - -template <typename T, AllocSpec Spec> -int ThrowingAllocator<T, Spec>::next_id_ = 0; - -// Tests for resource leaks by attempting to construct a T using args repeatedly -// until successful, using the countdown method. Side effects can then be -// tested for resource leaks. -template <typename T, typename... Args> -void TestThrowingCtor(Args&&... args) { - struct Cleanup { - ~Cleanup() { exceptions_internal::UnsetCountdown(); } - } c; - for (int count = 0;; ++count) { - exceptions_internal::ConstructorTracker ct(count); - exceptions_internal::SetCountdown(count); - try { - T temp(std::forward<Args>(args)...); - static_cast<void>(temp); - break; - } catch (const exceptions_internal::TestException&) { - } - } -} - -// Tests the nothrow guarantee of the provided nullary operation. If the an -// exception is thrown, the result will be AssertionFailure(). Otherwise, it -// will be AssertionSuccess(). -template <typename Operation> -testing::AssertionResult TestNothrowOp(const Operation& operation) { - struct Cleanup { - Cleanup() { exceptions_internal::SetCountdown(); } - ~Cleanup() { exceptions_internal::UnsetCountdown(); } - } c; - try { - operation(); - return testing::AssertionSuccess(); - } catch (const exceptions_internal::TestException&) { - return testing::AssertionFailure() - << "TestException thrown during call to operation() when nothrow " - "guarantee was expected."; - } catch (...) { - return testing::AssertionFailure() - << "Unknown exception thrown during call to operation() when " - "nothrow guarantee was expected."; - } -} - -namespace exceptions_internal { - -// Dummy struct for ExceptionSafetyTestBuilder<> partial state. -struct UninitializedT {}; - -template <typename T> -class DefaultFactory { - public: - explicit DefaultFactory(const T& t) : t_(t) {} - std::unique_ptr<T> operator()() const { return absl::make_unique<T>(t_); } - - private: - T t_; -}; - -template <size_t LazyContractsCount, typename LazyFactory, - typename LazyOperation> -using EnableIfTestable = typename absl::enable_if_t< - LazyContractsCount != 0 && - !std::is_same<LazyFactory, UninitializedT>::value && - !std::is_same<LazyOperation, UninitializedT>::value>; - -template <typename Factory = UninitializedT, - typename Operation = UninitializedT, typename... Contracts> -class ExceptionSafetyTestBuilder; - -} // namespace exceptions_internal - -/* - * Constructs an empty ExceptionSafetyTestBuilder. All - * ExceptionSafetyTestBuilder objects are immutable and all With[thing] mutation - * methods return new instances of ExceptionSafetyTestBuilder. - * - * In order to test a T for exception safety, a factory for that T, a testable - * operation, and at least one contract callback returning an assertion - * result must be applied using the respective methods. - */ -exceptions_internal::ExceptionSafetyTestBuilder<> MakeExceptionSafetyTester(); - -namespace exceptions_internal { -template <typename T> -struct IsUniquePtr : std::false_type {}; - -template <typename T, typename D> -struct IsUniquePtr<std::unique_ptr<T, D>> : std::true_type {}; - -template <typename Factory> -struct FactoryPtrTypeHelper { - using type = decltype(std::declval<const Factory&>()()); - - static_assert(IsUniquePtr<type>::value, "Factories must return a unique_ptr"); -}; - -template <typename Factory> -using FactoryPtrType = typename FactoryPtrTypeHelper<Factory>::type; - -template <typename Factory> -using FactoryElementType = typename FactoryPtrType<Factory>::element_type; - -template <typename T> -class ExceptionSafetyTest { - using Factory = std::function<std::unique_ptr<T>()>; - using Operation = std::function<void(T*)>; - using Contract = std::function<AssertionResult(T*)>; - - public: - template <typename... Contracts> - explicit ExceptionSafetyTest(const Factory& f, const Operation& op, - const Contracts&... contracts) - : factory_(f), operation_(op), contracts_{WrapContract(contracts)...} {} - - AssertionResult Test() const { - for (int count = 0;; ++count) { - exceptions_internal::ConstructorTracker ct(count); - - for (const auto& contract : contracts_) { - auto t_ptr = factory_(); - try { - SetCountdown(count); - operation_(t_ptr.get()); - // Unset for the case that the operation throws no exceptions, which - // would leave the countdown set and break the *next* exception safety - // test after this one. - UnsetCountdown(); - return AssertionSuccess(); - } catch (const exceptions_internal::TestException& e) { - if (!contract(t_ptr.get())) { - return AssertionFailure() << e.what() << " failed contract check"; - } - } - } - } - } - - private: - template <typename ContractFn> - Contract WrapContract(const ContractFn& contract) { - return [contract](T* t_ptr) { return AssertionResult(contract(t_ptr)); }; - } - - Contract WrapContract(StrongGuaranteeTagType) { - return [this](T* t_ptr) { return AssertionResult(*factory_() == *t_ptr); }; - } - - Factory factory_; - Operation operation_; - std::vector<Contract> contracts_; -}; - -/* - * Builds a tester object that tests if performing a operation on a T follows - * exception safety guarantees. Verification is done via contract assertion - * callbacks applied to T instances post-throw. - * - * Template parameters for ExceptionSafetyTestBuilder: - * - * - Factory: The factory object (passed in via tester.WithFactory(...) or - * tester.WithInitialValue(...)) must be invocable with the signature - * `std::unique_ptr<T> operator()() const` where T is the type being tested. - * It is used for reliably creating identical T instances to test on. - * - * - Operation: The operation object (passsed in via tester.WithOperation(...) - * or tester.Test(...)) must be invocable with the signature - * `void operator()(T*) const` where T is the type being tested. It is used - * for performing steps on a T instance that may throw and that need to be - * checked for exception safety. Each call to the operation will receive a - * fresh T instance so it's free to modify and destroy the T instances as it - * pleases. - * - * - Contracts...: The contract assertion callback objects (passed in via - * tester.WithContracts(...)) must be invocable with the signature - * `testing::AssertionResult operator()(T*) const` where T is the type being - * tested. Contract assertion callbacks are provided T instances post-throw. - * They must return testing::AssertionSuccess when the type contracts of the - * provided T instance hold. If the type contracts of the T instance do not - * hold, they must return testing::AssertionFailure. Execution order of - * Contracts... is unspecified. They will each individually get a fresh T - * instance so they are free to modify and destroy the T instances as they - * please. - */ -template <typename Factory, typename Operation, typename... Contracts> -class ExceptionSafetyTestBuilder { - public: - /* - * Returns a new ExceptionSafetyTestBuilder with an included T factory based - * on the provided T instance. The existing factory will not be included in - * the newly created tester instance. The created factory returns a new T - * instance by copy-constructing the provided const T& t. - * - * Preconditions for tester.WithInitialValue(const T& t): - * - * - The const T& t object must be copy-constructible where T is the type - * being tested. For non-copy-constructible objects, use the method - * tester.WithFactory(...). - */ - template <typename T> - ExceptionSafetyTestBuilder<DefaultFactory<T>, Operation, Contracts...> - WithInitialValue(const T& t) const { - return WithFactory(DefaultFactory<T>(t)); - } - - /* - * Returns a new ExceptionSafetyTestBuilder with the provided T factory - * included. The existing factory will not be included in the newly-created - * tester instance. This method is intended for use with types lacking a copy - * constructor. Types that can be copy-constructed should instead use the - * method tester.WithInitialValue(...). - */ - template <typename NewFactory> - ExceptionSafetyTestBuilder<absl::decay_t<NewFactory>, Operation, Contracts...> - WithFactory(const NewFactory& new_factory) const { - return {new_factory, operation_, contracts_}; - } - - /* - * Returns a new ExceptionSafetyTestBuilder with the provided testable - * operation included. The existing operation will not be included in the - * newly created tester. - */ - template <typename NewOperation> - ExceptionSafetyTestBuilder<Factory, absl::decay_t<NewOperation>, Contracts...> - WithOperation(const NewOperation& new_operation) const { - return {factory_, new_operation, contracts_}; - } - - /* - * Returns a new ExceptionSafetyTestBuilder with the provided MoreContracts... - * combined with the Contracts... that were already included in the instance - * on which the method was called. Contracts... cannot be removed or replaced - * once added to an ExceptionSafetyTestBuilder instance. A fresh object must - * be created in order to get an empty Contracts... list. - * - * In addition to passing in custom contract assertion callbacks, this method - * accepts `testing::strong_guarantee` as an argument which checks T instances - * post-throw against freshly created T instances via operator== to verify - * that any state changes made during the execution of the operation were - * properly rolled back. - */ - template <typename... MoreContracts> - ExceptionSafetyTestBuilder<Factory, Operation, Contracts..., - absl::decay_t<MoreContracts>...> - WithContracts(const MoreContracts&... more_contracts) const { - return { - factory_, operation_, - std::tuple_cat(contracts_, std::tuple<absl::decay_t<MoreContracts>...>( - more_contracts...))}; - } - - /* - * Returns a testing::AssertionResult that is the reduced result of the - * exception safety algorithm. The algorithm short circuits and returns - * AssertionFailure after the first contract callback returns an - * AssertionFailure. Otherwise, if all contract callbacks return an - * AssertionSuccess, the reduced result is AssertionSuccess. - * - * The passed-in testable operation will not be saved in a new tester instance - * nor will it modify/replace the existing tester instance. This is useful - * when each operation being tested is unique and does not need to be reused. - * - * Preconditions for tester.Test(const NewOperation& new_operation): - * - * - May only be called after at least one contract assertion callback and a - * factory or initial value have been provided. - */ - template < - typename NewOperation, - typename = EnableIfTestable<sizeof...(Contracts), Factory, NewOperation>> - testing::AssertionResult Test(const NewOperation& new_operation) const { - return TestImpl(new_operation, absl::index_sequence_for<Contracts...>()); - } - - /* - * Returns a testing::AssertionResult that is the reduced result of the - * exception safety algorithm. The algorithm short circuits and returns - * AssertionFailure after the first contract callback returns an - * AssertionFailure. Otherwise, if all contract callbacks return an - * AssertionSuccess, the reduced result is AssertionSuccess. - * - * Preconditions for tester.Test(): - * - * - May only be called after at least one contract assertion callback, a - * factory or initial value and a testable operation have been provided. - */ - template < - typename LazyOperation = Operation, - typename = EnableIfTestable<sizeof...(Contracts), Factory, LazyOperation>> - testing::AssertionResult Test() const { - return Test(operation_); - } - - private: - template <typename, typename, typename...> - friend class ExceptionSafetyTestBuilder; - - friend ExceptionSafetyTestBuilder<> testing::MakeExceptionSafetyTester(); - - ExceptionSafetyTestBuilder() {} - - ExceptionSafetyTestBuilder(const Factory& f, const Operation& o, - const std::tuple<Contracts...>& i) - : factory_(f), operation_(o), contracts_(i) {} - - template <typename SelectedOperation, size_t... Indices> - testing::AssertionResult TestImpl(SelectedOperation selected_operation, - absl::index_sequence<Indices...>) const { - return ExceptionSafetyTest<FactoryElementType<Factory>>( - factory_, selected_operation, std::get<Indices>(contracts_)...) - .Test(); - } - - Factory factory_; - Operation operation_; - std::tuple<Contracts...> contracts_; -}; - -} // namespace exceptions_internal - -} // namespace testing - -#endif // ABSL_HAVE_EXCEPTIONS - -#endif // ABSL_BASE_INTERNAL_EXCEPTION_SAFETY_TESTING_H_ |