diff options
author | Abseil Team <absl-team@google.com> | 2020-09-18 15:55:15 -0700 |
---|---|---|
committer | Derek Mauro <dmauro@google.com> | 2020-09-24 13:47:15 -0400 |
commit | b56cbdd23834a65682c0b46f367f8679e83bc894 (patch) | |
tree | dacab9a64dd1a9e9668737e511d1a5420ff96001 /absl/random/internal/mock_helpers.h | |
parent | b832dce8489ef7b6231384909fd9b68d5a5ff2b7 (diff) |
Abseil LTS 2020092320200923
What's New:
* `absl::StatusOr<T>` has been released. See our [blog
post](https://abseil.io/blog/2020-091021-status) for more
information.
* Abseil Flags reflection interfaces have been released.
* Abseil Flags memory usage has been significantly optimized.
* Abseil now supports a "hardened" build mode. This build mode enables
runtime checks that guard against programming errors that may lead
to security vulnerabilities.
Notable Fixes:
* Sanitizer dynamic annotations like `AnnotateRWLockCreate` that are
also defined by the compiler sanitizer implementation are no longer
also defined by Abseil.
* Sanitizer macros are now prefixed with `ABSL_` to avoid naming collisions.
* Sanitizer usage is now automatically detected and no longer requires
macros like `ADDRESS_SANITIZER` to be defined on the command line.
Breaking Changes:
* Abseil no longer contains a `dynamic_annotations` library. Users
using a supported build system (Bazel or CMake) are unaffected by
this, but users manually specifying link libraries may get an error
about a missing linker input.
Baseline: 7680a5f8efe32de4753baadbd63e74e59d95bac1
Cherry picks: None
Diffstat (limited to 'absl/random/internal/mock_helpers.h')
-rw-r--r-- | absl/random/internal/mock_helpers.h | 127 |
1 files changed, 127 insertions, 0 deletions
diff --git a/absl/random/internal/mock_helpers.h b/absl/random/internal/mock_helpers.h new file mode 100644 index 00000000..9af27ab3 --- /dev/null +++ b/absl/random/internal/mock_helpers.h @@ -0,0 +1,127 @@ +// +// Copyright 2019 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. + +#ifndef ABSL_RANDOM_INTERNAL_MOCK_HELPERS_H_ +#define ABSL_RANDOM_INTERNAL_MOCK_HELPERS_H_ + +#include <tuple> +#include <type_traits> + +#include "absl/base/internal/fast_type_id.h" +#include "absl/types/optional.h" + +namespace absl { +ABSL_NAMESPACE_BEGIN +namespace random_internal { + +// MockHelpers works in conjunction with MockOverloadSet, MockingBitGen, and +// BitGenRef to enable the mocking capability for absl distribution functions. +// +// MockingBitGen registers mocks based on the typeid of a mock signature, KeyT, +// which is used to generate a unique id. +// +// KeyT is a signature of the form: +// result_type(discriminator_type, std::tuple<args...>) +// The mocked function signature will be composed from KeyT as: +// result_type(args...) +// +class MockHelpers { + using IdType = ::absl::base_internal::FastTypeIdType; + + // Given a key signature type used to index the mock, extract the components. + // KeyT is expected to have the form: + // result_type(discriminator_type, arg_tuple_type) + template <typename KeyT> + struct KeySignature; + + template <typename ResultT, typename DiscriminatorT, typename ArgTupleT> + struct KeySignature<ResultT(DiscriminatorT, ArgTupleT)> { + using result_type = ResultT; + using discriminator_type = DiscriminatorT; + using arg_tuple_type = ArgTupleT; + }; + + // Detector for InvokeMock. + template <class T> + using invoke_mock_t = decltype(std::declval<T*>()->InvokeMock( + std::declval<IdType>(), std::declval<void*>(), std::declval<void*>())); + + // Empty implementation of InvokeMock. + template <typename KeyT, typename ReturnT, typename ArgTupleT, typename URBG, + typename... Args> + static absl::optional<ReturnT> InvokeMockImpl(char, URBG*, Args&&...) { + return absl::nullopt; + } + + // Non-empty implementation of InvokeMock. + template <typename KeyT, typename ReturnT, typename ArgTupleT, typename URBG, + typename = invoke_mock_t<URBG>, typename... Args> + static absl::optional<ReturnT> InvokeMockImpl(int, URBG* urbg, + Args&&... args) { + ArgTupleT arg_tuple(std::forward<Args>(args)...); + ReturnT result; + if (urbg->InvokeMock(::absl::base_internal::FastTypeId<KeyT>(), &arg_tuple, + &result)) { + return result; + } + return absl::nullopt; + } + + public: + // Invoke a mock for the KeyT (may or may not be a signature). + // + // KeyT is used to generate a typeid-based lookup key for the mock. + // KeyT is a signature of the form: + // result_type(discriminator_type, std::tuple<args...>) + // The mocked function signature will be composed from KeyT as: + // result_type(args...) + // + // An instance of arg_tuple_type must be constructable from Args..., since + // the underlying mechanism requires a pointer to an argument tuple. + template <typename KeyT, typename URBG, typename... Args> + static auto MaybeInvokeMock(URBG* urbg, Args&&... args) + -> absl::optional<typename KeySignature<KeyT>::result_type> { + // Use function overloading to dispatch to the implemenation since + // more modern patterns (e.g. require + constexpr) are not supported in all + // compiler configurations. + return InvokeMockImpl<KeyT, typename KeySignature<KeyT>::result_type, + typename KeySignature<KeyT>::arg_tuple_type, URBG>( + 0, urbg, std::forward<Args>(args)...); + } + + // Acquire a mock for the KeyT (may or may not be a signature). + // + // KeyT is used to generate a typeid-based lookup for the mock. + // KeyT is a signature of the form: + // result_type(discriminator_type, std::tuple<args...>) + // The mocked function signature will be composed from KeyT as: + // result_type(args...) + template <typename KeyT, typename MockURBG> + static auto MockFor(MockURBG& m) -> decltype( + std::declval<MockURBG>() + .template RegisterMock<typename KeySignature<KeyT>::result_type, + typename KeySignature<KeyT>::arg_tuple_type>( + std::declval<IdType>())) { + return m.template RegisterMock<typename KeySignature<KeyT>::result_type, + typename KeySignature<KeyT>::arg_tuple_type>( + ::absl::base_internal::FastTypeId<KeyT>()); + } +}; + +} // namespace random_internal +ABSL_NAMESPACE_END +} // namespace absl + +#endif // ABSL_RANDOM_INTERNAL_MOCK_HELPERS_H_ |