| // | |
| // Copyright 2020 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. | |
| // | |
| // ----------------------------------------------------------------------------- | |
| // File: reflection.h | |
| // ----------------------------------------------------------------------------- | |
| // | |
| // This file defines the routines to access and operate on an Abseil Flag's | |
| // reflection handle. | |
| namespace absl { | |
| ABSL_NAMESPACE_BEGIN | |
| namespace flags_internal { | |
| class FlagSaverImpl; | |
| } // namespace flags_internal | |
| // FindCommandLineFlag() | |
| // | |
| // Returns the reflection handle of an Abseil flag of the specified name, or | |
| // `nullptr` if not found. This function will emit a warning if the name of a | |
| // 'retired' flag is specified. | |
| absl::CommandLineFlag* FindCommandLineFlag(absl::string_view name); | |
| // Returns current state of the Flags registry in a form of mapping from flag | |
| // name to a flag reflection handle. | |
| absl::flat_hash_map<absl::string_view, absl::CommandLineFlag*> GetAllFlags(); | |
| //------------------------------------------------------------------------------ | |
| // FlagSaver | |
| //------------------------------------------------------------------------------ | |
| // | |
| // A FlagSaver object stores the state of flags in the scope where the FlagSaver | |
| // is defined, allowing modification of those flags within that scope and | |
| // automatic restoration of the flags to their previous state upon leaving the | |
| // scope. | |
| // | |
| // A FlagSaver can be used within tests to temporarily change the test | |
| // environment and restore the test case to its previous state. | |
| // | |
| // Example: | |
| // | |
| // void MyFunc() { | |
| // absl::FlagSaver fs; | |
| // ... | |
| // absl::SetFlag(&FLAGS_myFlag, otherValue); | |
| // ... | |
| // } // scope of FlagSaver left, flags return to previous state | |
| // | |
| // This class is thread-safe. | |
| class FlagSaver { | |
| public: | |
| FlagSaver(); | |
| ~FlagSaver(); | |
| FlagSaver(const FlagSaver&) = delete; | |
| void operator=(const FlagSaver&) = delete; | |
| private: | |
| flags_internal::FlagSaverImpl* impl_; | |
| }; | |
| //----------------------------------------------------------------------------- | |
| ABSL_NAMESPACE_END | |
| } // namespace absl | |