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diff --git a/lldb/unittests/TestingSupport/SubsystemRAII.h b/lldb/unittests/TestingSupport/SubsystemRAII.h
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+//===- SubsystemRAII.h ------------------------------------------*- C++ -*-===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLDB_UNITTESTS_TESTINGSUPPORT_SUBSYSTEMRAII_H
+#define LLDB_UNITTESTS_TESTINGSUPPORT_SUBSYSTEMRAII_H
+
+#include "llvm/Support/Error.h"
+#include "llvm/Testing/Support/Error.h"
+#include "gtest/gtest.h"
+#include <type_traits>
+
+namespace lldb_private {
+
+namespace detail {
+/// Initializes and deinitializes a single subsystem.
+/// @see SubsystemRAII
+template <typename T> struct SubsystemRAIICase {
+
+  /// Calls ::Initialize if it has a void return type.
+  template <typename U = T>
+  typename std::enable_if<
+      std::is_same<decltype(U::Initialize()), void>::value>::type
+  CallInitialize() {
+    T::Initialize();
+  }
+
+  /// Calls ::Initialize if it has a llvm::Error return type and checks
+  /// the Error instance for success.
+  template <typename U = T>
+  typename std::enable_if<
+      std::is_same<decltype(U::Initialize()), llvm::Error>::value>::type
+  CallInitialize() {
+    ASSERT_THAT_ERROR(T::Initialize(), llvm::Succeeded());
+  }
+
+  SubsystemRAIICase() { CallInitialize(); }
+  ~SubsystemRAIICase() { T::Terminate(); }
+};
+} // namespace detail
+
+template <typename... T> class SubsystemRAII {};
+
+/// RAII for initializing and deinitializing LLDB subsystems.
+///
+/// This RAII takes care of calling the Initialize and Terminate functions for
+/// the subsystems specified by its template arguments. The ::Initialize
+/// functions are called on construction for each subsystem template parameter
+/// in the order in which they are passed as template parameters.
+/// The ::Terminate functions are called in the reverse order at destruction
+/// time.
+///
+/// If the ::Initialize function returns an llvm::Error this function handles
+/// the Error instance (by checking that there is no error).
+///
+/// Constructing this RAII in a scope like this:
+///
+///   @code{.cpp}
+///   {
+///     SubsystemRAII<FileSystem, HostInfo, Socket> Subsystems;
+///     DoingTestWork();
+///   }
+///   @endcode
+///
+/// is equivalent to the following code:
+///
+///   @code{.cpp}
+///   {
+///     FileSystem::Initialize();
+///     HostInfo::Initialize();
+///     ASSERT_THAT_ERROR(Socket::Initialize(), llvm::Succeeded());
+///
+///     DoingTestWork();
+///
+///     Socket::Terminate();
+///     FileSystem::Terminate();
+///     HostInfo::Terminate();
+///   }
+///   @endcode
+template <typename T, typename... Ts> class SubsystemRAII<T, Ts...> {
+  detail::SubsystemRAIICase<T> CurrentSubsystem;
+  SubsystemRAII<Ts...> RemainingSubsystems;
+};
+} // namespace lldb_private
+
+#endif // LLDB_UNITTESTS_TESTINGSUPPORT_SUBSYSTEMRAII_H