v8/test/common/flag-utils.h
Santiago Aboy Solanes 14c5b0ae67 [config] Add V8_NODISCARD for Scope classes
Scopes in V8 are used to guarantee one or more properties during its
lifetimes. If a scope is not named e.g MyClassScope(args) instead of
MyClassScope scope(args) it will get created and automatically destroyed
and therefore, being useless as a scope. This CL would produce a
compiling warning when that happens to ward off this developer error.

Follow-up to ccrev.com/2552415 in which it was introduced and
implemented for Guard classes.

Change-Id: Ifa0fb89cc3d9bdcdee0fd8150a2618af5ef45cbf
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2555001
Commit-Queue: Santiago Aboy Solanes <solanes@chromium.org>
Reviewed-by: Ulan Degenbaev <ulan@chromium.org>
Reviewed-by: Leszek Swirski <leszeks@chromium.org>
Reviewed-by: Michael Lippautz <mlippautz@chromium.org>
Reviewed-by: Jakob Kummerow <jkummerow@chromium.org>
Reviewed-by: Ross McIlroy <rmcilroy@chromium.org>
Reviewed-by: Tobias Tebbi <tebbi@chromium.org>
Cr-Commit-Position: refs/heads/master@{#71425}
2020-11-26 11:08:45 +00:00

39 lines
1.0 KiB
C++

// Copyright 2020 the V8 project authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#ifndef V8_TEST_COMMON_FLAG_UTILS_H
#define V8_TEST_COMMON_FLAG_UTILS_H
namespace v8 {
namespace internal {
template <typename T>
class V8_NODISCARD FlagScope {
public:
FlagScope(T* flag, T new_value) : flag_(flag), previous_value_(*flag) {
*flag = new_value;
}
~FlagScope() { *flag_ = previous_value_; }
private:
T* flag_;
T previous_value_;
};
#define FLAG_SCOPE(flag) \
FlagScope<bool> __scope_##flag##__LINE__(&FLAG_##flag, true)
} // namespace internal
} // namespace v8
#define FLAG_SCOPE_EXTERNAL(flag) \
v8::internal::FlagScope<bool> __scope_##flag##__LINE__( \
&v8::internal::FLAG_##flag, true)
#define UNFLAG_SCOPE_EXTERNAL(flag) \
v8::internal::FlagScope<bool> __scope_##flag##__LINE__( \
&v8::internal::FLAG_##flag, false)
#endif // V8_TEST_COMMON_FLAG_UTILS_H