perfetto: introduce base::optional
Change-Id: I6b01026f677b1b9d3225561feb558d93ed10a36b
diff --git a/Android.bp b/Android.bp
index 8bb0a4c..f6762ed 100644
--- a/Android.bp
+++ b/Android.bp
@@ -4483,6 +4483,7 @@
"src/base/event.cc",
"src/base/file_utils.cc",
"src/base/metatrace.cc",
+ "src/base/optional_unittest.cc",
"src/base/paged_memory.cc",
"src/base/paged_memory_unittest.cc",
"src/base/scoped_file_unittest.cc",
diff --git a/include/perfetto/base/BUILD.gn b/include/perfetto/base/BUILD.gn
index 807e948..05baf78 100644
--- a/include/perfetto/base/BUILD.gn
+++ b/include/perfetto/base/BUILD.gn
@@ -24,6 +24,7 @@
"gtest_prod_util.h",
"logging.h",
"metatrace.h",
+ "optional.h",
"paged_memory.h",
"scoped_file.h",
"small_set.h",
diff --git a/include/perfetto/base/optional.h b/include/perfetto/base/optional.h
new file mode 100644
index 0000000..1f51582
--- /dev/null
+++ b/include/perfetto/base/optional.h
@@ -0,0 +1,934 @@
+/*
+ * Copyright (C) 2018 The Android Open Source Project
+ *
+ * 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
+ *
+ * http://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 INCLUDE_PERFETTO_BASE_OPTIONAL_H_
+#define INCLUDE_PERFETTO_BASE_OPTIONAL_H_
+
+#include <type_traits>
+#include <utility>
+
+#include "perfetto/base/logging.h"
+
+namespace perfetto {
+namespace base {
+
+// Specification:
+// http://en.cppreference.com/w/cpp/utility/optional/in_place_t
+struct in_place_t {};
+
+// Specification:
+// http://en.cppreference.com/w/cpp/utility/optional/nullopt_t
+struct nullopt_t {
+ constexpr explicit nullopt_t(int) {}
+};
+
+// Specification:
+// http://en.cppreference.com/w/cpp/utility/optional/in_place
+constexpr in_place_t in_place = {};
+
+// Specification:
+// http://en.cppreference.com/w/cpp/utility/optional/nullopt
+constexpr nullopt_t nullopt(0);
+
+// Forward declaration, which is refered by following helpers.
+template <typename T>
+class Optional;
+
+namespace internal {
+
+template <typename T, bool = std::is_trivially_destructible<T>::value>
+struct OptionalStorageBase {
+ // Initializing |empty_| here instead of using default member initializing
+ // to avoid errors in g++ 4.8.
+ constexpr OptionalStorageBase() : empty_('\0') {}
+
+ template <class... Args>
+ constexpr explicit OptionalStorageBase(in_place_t, Args&&... args)
+ : is_populated_(true), value_(std::forward<Args>(args)...) {}
+
+ // When T is not trivially destructible we must call its
+ // destructor before deallocating its memory.
+ // Note that this hides the (implicitly declared) move constructor, which
+ // would be used for constexpr move constructor in OptionalStorage<T>.
+ // It is needed iff T is trivially move constructible. However, the current
+ // is_trivially_{copy,move}_constructible implementation requires
+ // is_trivially_destructible (which looks a bug, cf:
+ // https://gcc.gnu.org/bugzilla/show_bug.cgi?id=51452 and
+ // http://cplusplus.github.io/LWG/lwg-active.html#2116), so it is not
+ // necessary for this case at the moment. Please see also the destructor
+ // comment in "is_trivially_destructible = true" specialization below.
+ ~OptionalStorageBase() {
+ if (is_populated_)
+ value_.~T();
+ }
+
+ template <class... Args>
+ void Init(Args&&... args) {
+ PERFETTO_DCHECK(!is_populated_);
+ ::new (&value_) T(std::forward<Args>(args)...);
+ is_populated_ = true;
+ }
+
+ bool is_populated_ = false;
+ union {
+ // |empty_| exists so that the union will always be initialized, even when
+ // it doesn't contain a value. Union members must be initialized for the
+ // constructor to be 'constexpr'.
+ char empty_;
+ T value_;
+ };
+};
+
+template <typename T>
+struct OptionalStorageBase<T, true /* trivially destructible */> {
+ // Initializing |empty_| here instead of using default member initializing
+ // to avoid errors in g++ 4.8.
+ constexpr OptionalStorageBase() : empty_('\0') {}
+
+ template <class... Args>
+ constexpr explicit OptionalStorageBase(in_place_t, Args&&... args)
+ : is_populated_(true), value_(std::forward<Args>(args)...) {}
+
+ // When T is trivially destructible (i.e. its destructor does nothing) there
+ // is no need to call it. Implicitly defined destructor is trivial, because
+ // both members (bool and union containing only variants which are trivially
+ // destructible) are trivially destructible.
+ // Explicitly-defaulted destructor is also trivial, but do not use it here,
+ // because it hides the implicit move constructor. It is needed to implement
+ // constexpr move constructor in OptionalStorage iff T is trivially move
+ // constructible. Note that, if T is trivially move constructible, the move
+ // constructor of OptionalStorageBase<T> is also implicitly defined and it is
+ // trivially move constructor. If T is not trivially move constructible,
+ // "not declaring move constructor without destructor declaration" here means
+ // "delete move constructor", which works because any move constructor of
+ // OptionalStorage will not refer to it in that case.
+
+ template <class... Args>
+ void Init(Args&&... args) {
+ PERFETTO_DCHECK(!is_populated_);
+ ::new (&value_) T(std::forward<Args>(args)...);
+ is_populated_ = true;
+ }
+
+ bool is_populated_ = false;
+ union {
+ // |empty_| exists so that the union will always be initialized, even when
+ // it doesn't contain a value. Union members must be initialized for the
+ // constructor to be 'constexpr'.
+ char empty_;
+ T value_;
+ };
+};
+
+// Implement conditional constexpr copy and move constructors. These are
+// constexpr if is_trivially_{copy,move}_constructible<T>::value is true
+// respectively. If each is true, the corresponding constructor is defined as
+// "= default;", which generates a constexpr constructor (In this case,
+// the condition of constexpr-ness is satisfied because the base class also has
+// compiler generated constexpr {copy,move} constructors). Note that
+// placement-new is prohibited in constexpr.
+template <typename T,
+ bool = std::is_trivially_copy_constructible<T>::value,
+ bool = std::is_trivially_move_constructible<T>::value>
+struct OptionalStorage : OptionalStorageBase<T> {
+ // This is no trivially {copy,move} constructible case. Other cases are
+ // defined below as specializations.
+
+ // Accessing the members of template base class requires explicit
+ // declaration.
+ using OptionalStorageBase<T>::is_populated_;
+ using OptionalStorageBase<T>::value_;
+ using OptionalStorageBase<T>::Init;
+
+ // Inherit constructors (specifically, the in_place constructor).
+ using OptionalStorageBase<T>::OptionalStorageBase;
+
+ // User defined constructor deletes the default constructor.
+ // Define it explicitly.
+ OptionalStorage() = default;
+
+ OptionalStorage(const OptionalStorage& other) {
+ if (other.is_populated_)
+ Init(other.value_);
+ }
+
+ OptionalStorage(OptionalStorage&& other) noexcept(
+ std::is_nothrow_move_constructible<T>::value) {
+ if (other.is_populated_)
+ Init(std::move(other.value_));
+ }
+};
+
+template <typename T>
+struct OptionalStorage<T,
+ true /* trivially copy constructible */,
+ false /* trivially move constructible */>
+ : OptionalStorageBase<T> {
+ using OptionalStorageBase<T>::is_populated_;
+ using OptionalStorageBase<T>::value_;
+ using OptionalStorageBase<T>::Init;
+ using OptionalStorageBase<T>::OptionalStorageBase;
+
+ OptionalStorage() = default;
+ OptionalStorage(const OptionalStorage& other) = default;
+
+ OptionalStorage(OptionalStorage&& other) noexcept(
+ std::is_nothrow_move_constructible<T>::value) {
+ if (other.is_populated_)
+ Init(std::move(other.value_));
+ }
+};
+
+template <typename T>
+struct OptionalStorage<T,
+ false /* trivially copy constructible */,
+ true /* trivially move constructible */>
+ : OptionalStorageBase<T> {
+ using OptionalStorageBase<T>::is_populated_;
+ using OptionalStorageBase<T>::value_;
+ using OptionalStorageBase<T>::Init;
+ using OptionalStorageBase<T>::OptionalStorageBase;
+
+ OptionalStorage() = default;
+ OptionalStorage(OptionalStorage&& other) = default;
+
+ OptionalStorage(const OptionalStorage& other) {
+ if (other.is_populated_)
+ Init(other.value_);
+ }
+};
+
+template <typename T>
+struct OptionalStorage<T,
+ true /* trivially copy constructible */,
+ true /* trivially move constructible */>
+ : OptionalStorageBase<T> {
+ // If both trivially {copy,move} constructible are true, it is not necessary
+ // to use user-defined constructors. So, just inheriting constructors
+ // from the base class works.
+ using OptionalStorageBase<T>::OptionalStorageBase;
+};
+
+// Base class to support conditionally usable copy-/move- constructors
+// and assign operators.
+template <typename T>
+class OptionalBase {
+ // This class provides implementation rather than public API, so everything
+ // should be hidden. Often we use composition, but we cannot in this case
+ // because of C++ language restriction.
+ protected:
+ constexpr OptionalBase() = default;
+ constexpr OptionalBase(const OptionalBase& other) = default;
+ constexpr OptionalBase(OptionalBase&& other) = default;
+
+ template <class... Args>
+ constexpr explicit OptionalBase(in_place_t, Args&&... args)
+ : storage_(in_place, std::forward<Args>(args)...) {}
+
+ // Implementation of converting constructors.
+ template <typename U>
+ explicit OptionalBase(const OptionalBase<U>& other) {
+ if (other.storage_.is_populated_)
+ storage_.Init(other.storage_.value_);
+ }
+
+ template <typename U>
+ explicit OptionalBase(OptionalBase<U>&& other) {
+ if (other.storage_.is_populated_)
+ storage_.Init(std::move(other.storage_.value_));
+ }
+
+ ~OptionalBase() = default;
+
+ OptionalBase& operator=(const OptionalBase& other) {
+ CopyAssign(other);
+ return *this;
+ }
+
+ OptionalBase& operator=(OptionalBase&& other) noexcept(
+ std::is_nothrow_move_assignable<T>::value&&
+ std::is_nothrow_move_constructible<T>::value) {
+ MoveAssign(std::move(other));
+ return *this;
+ }
+
+ template <typename U>
+ void CopyAssign(const OptionalBase<U>& other) {
+ if (other.storage_.is_populated_)
+ InitOrAssign(other.storage_.value_);
+ else
+ FreeIfNeeded();
+ }
+
+ template <typename U>
+ void MoveAssign(OptionalBase<U>&& other) {
+ if (other.storage_.is_populated_)
+ InitOrAssign(std::move(other.storage_.value_));
+ else
+ FreeIfNeeded();
+ }
+
+ template <typename U>
+ void InitOrAssign(U&& value) {
+ if (storage_.is_populated_)
+ storage_.value_ = std::forward<U>(value);
+ else
+ storage_.Init(std::forward<U>(value));
+ }
+
+ void FreeIfNeeded() {
+ if (!storage_.is_populated_)
+ return;
+ storage_.value_.~T();
+ storage_.is_populated_ = false;
+ }
+
+ // For implementing conversion, allow access to other typed OptionalBase
+ // class.
+ template <typename U>
+ friend class OptionalBase;
+
+ OptionalStorage<T> storage_;
+};
+
+// The following {Copy,Move}{Constructible,Assignable} structs are helpers to
+// implement constructor/assign-operator overloading. Specifically, if T is
+// is not movable but copyable, Optional<T>'s move constructor should not
+// participate in overload resolution. This inheritance trick implements that.
+template <bool is_copy_constructible>
+struct CopyConstructible {};
+
+template <>
+struct CopyConstructible<false> {
+ constexpr CopyConstructible() = default;
+ constexpr CopyConstructible(const CopyConstructible&) = delete;
+ constexpr CopyConstructible(CopyConstructible&&) = default;
+ CopyConstructible& operator=(const CopyConstructible&) = default;
+ CopyConstructible& operator=(CopyConstructible&&) = default;
+};
+
+template <bool is_move_constructible>
+struct MoveConstructible {};
+
+template <>
+struct MoveConstructible<false> {
+ constexpr MoveConstructible() = default;
+ constexpr MoveConstructible(const MoveConstructible&) = default;
+ constexpr MoveConstructible(MoveConstructible&&) = delete;
+ MoveConstructible& operator=(const MoveConstructible&) = default;
+ MoveConstructible& operator=(MoveConstructible&&) = default;
+};
+
+template <bool is_copy_assignable>
+struct CopyAssignable {};
+
+template <>
+struct CopyAssignable<false> {
+ constexpr CopyAssignable() = default;
+ constexpr CopyAssignable(const CopyAssignable&) = default;
+ constexpr CopyAssignable(CopyAssignable&&) = default;
+ CopyAssignable& operator=(const CopyAssignable&) = delete;
+ CopyAssignable& operator=(CopyAssignable&&) = default;
+};
+
+template <bool is_move_assignable>
+struct MoveAssignable {};
+
+template <>
+struct MoveAssignable<false> {
+ constexpr MoveAssignable() = default;
+ constexpr MoveAssignable(const MoveAssignable&) = default;
+ constexpr MoveAssignable(MoveAssignable&&) = default;
+ MoveAssignable& operator=(const MoveAssignable&) = default;
+ MoveAssignable& operator=(MoveAssignable&&) = delete;
+};
+
+// Helper to conditionally enable converting constructors and assign operators.
+template <typename T, typename U>
+struct IsConvertibleFromOptional
+ : std::integral_constant<
+ bool,
+ std::is_constructible<T, Optional<U>&>::value ||
+ std::is_constructible<T, const Optional<U>&>::value ||
+ std::is_constructible<T, Optional<U>&&>::value ||
+ std::is_constructible<T, const Optional<U>&&>::value ||
+ std::is_convertible<Optional<U>&, T>::value ||
+ std::is_convertible<const Optional<U>&, T>::value ||
+ std::is_convertible<Optional<U>&&, T>::value ||
+ std::is_convertible<const Optional<U>&&, T>::value> {};
+
+template <typename T, typename U>
+struct IsAssignableFromOptional
+ : std::integral_constant<
+ bool,
+ IsConvertibleFromOptional<T, U>::value ||
+ std::is_assignable<T&, Optional<U>&>::value ||
+ std::is_assignable<T&, const Optional<U>&>::value ||
+ std::is_assignable<T&, Optional<U>&&>::value ||
+ std::is_assignable<T&, const Optional<U>&&>::value> {};
+
+// Forward compatibility for C++17.
+// Introduce one more deeper nested namespace to avoid leaking using std::swap.
+namespace swappable_impl {
+using std::swap;
+
+struct IsSwappableImpl {
+ // Tests if swap can be called. Check<T&>(0) returns true_type iff swap is
+ // available for T. Otherwise, Check's overload resolution falls back to
+ // Check(...) declared below thanks to SFINAE, so returns false_type.
+ template <typename T>
+ static auto Check(int)
+ -> decltype(swap(std::declval<T>(), std::declval<T>()), std::true_type());
+
+ template <typename T>
+ static std::false_type Check(...);
+};
+} // namespace swappable_impl
+
+template <typename T>
+struct IsSwappable : decltype(swappable_impl::IsSwappableImpl::Check<T&>(0)) {};
+
+// Forward compatibility for C++20.
+template <typename T>
+using RemoveCvRefT =
+ typename std::remove_cv<typename std::remove_reference<T>::type>::type;
+
+} // namespace internal
+
+// On Windows, by default, empty-base class optimization does not work,
+// which means even if the base class is empty struct, it still consumes one
+// byte for its body. __declspec(empty_bases) enables the optimization.
+// cf)
+// https://blogs.msdn.microsoft.com/vcblog/2016/03/30/optimizing-the-layout-of-empty-base-classes-in-vs2015-update-2-3/
+#if PERFETTO_BUILDFLAG(PERFETTO_OS_WIN)
+#define OPTIONAL_DECLSPEC_EMPTY_BASES __declspec(empty_bases)
+#else
+#define OPTIONAL_DECLSPEC_EMPTY_BASES
+#endif
+
+// base::Optional is a Chromium version of the C++17 optional class:
+// std::optional documentation:
+// http://en.cppreference.com/w/cpp/utility/optional
+// Chromium documentation:
+// https://chromium.googlesource.com/chromium/src/+/master/docs/optional.md
+//
+// These are the differences between the specification and the implementation:
+// - Constructors do not use 'constexpr' as it is a C++14 extension.
+// - 'constexpr' might be missing in some places for reasons specified locally.
+// - No exceptions are thrown, because they are banned from Chromium.
+// Marked noexcept for only move constructor and move assign operators.
+// - All the non-members are in the 'base' namespace instead of 'std'.
+//
+// Note that T cannot have a constructor T(Optional<T>) etc. Optional<T>
+// PERFETTO_CHECKs T's constructor (specifically via IsConvertibleFromOptional),
+// and in the PERFETTO_CHECK whether T can be constructible from Optional<T>,
+// which is recursive so it does not work. As of Feb 2018, std::optional C++17
+// implementation in both clang and gcc has same limitation. MSVC SFINAE looks
+// to have different behavior, but anyway it reports an error, too.
+//
+// This file is a modified version of optional.h from Chromium at revision
+// 5e71bd454e60511c1293c0c686544aaa76094424. The changes remove C++14/C++17
+// specific code and replace with C++11 counterparts.
+template <typename T>
+class OPTIONAL_DECLSPEC_EMPTY_BASES Optional
+ : public internal::OptionalBase<T>,
+ public internal::CopyConstructible<std::is_copy_constructible<T>::value>,
+ public internal::MoveConstructible<std::is_move_constructible<T>::value>,
+ public internal::CopyAssignable<std::is_copy_constructible<T>::value &&
+ std::is_copy_assignable<T>::value>,
+ public internal::MoveAssignable<std::is_move_constructible<T>::value &&
+ std::is_move_assignable<T>::value> {
+ public:
+#undef OPTIONAL_DECLSPEC_EMPTY_BASES
+ using value_type = T;
+
+ // Defer default/copy/move constructor implementation to OptionalBase.
+ constexpr Optional() = default;
+ constexpr Optional(const Optional& other) = default;
+ constexpr Optional(Optional&& other) noexcept(
+ std::is_nothrow_move_constructible<T>::value) = default;
+
+ constexpr Optional(nullopt_t) {} // NOLINT(runtime/explicit)
+
+ // Converting copy constructor. "explicit" only if
+ // std::is_convertible<const U&, T>::value is false. It is implemented by
+ // declaring two almost same constructors, but that condition in enable_if_t
+ // is different, so that either one is chosen, thanks to SFINAE.
+ template <typename U,
+ typename std::enable_if<
+ std::is_constructible<T, const U&>::value &&
+ !internal::IsConvertibleFromOptional<T, U>::value &&
+ std::is_convertible<const U&, T>::value,
+ bool>::type = false>
+ Optional(const Optional<U>& other) : internal::OptionalBase<T>(other) {}
+
+ template <typename U,
+ typename std::enable_if<
+ std::is_constructible<T, const U&>::value &&
+ !internal::IsConvertibleFromOptional<T, U>::value &&
+ !std::is_convertible<const U&, T>::value,
+ bool>::type = false>
+ explicit Optional(const Optional<U>& other)
+ : internal::OptionalBase<T>(other) {}
+
+ // Converting move constructor. Similar to converting copy constructor,
+ // declaring two (explicit and non-explicit) constructors.
+ template <typename U,
+ typename std::enable_if<
+ std::is_constructible<T, U&&>::value &&
+ !internal::IsConvertibleFromOptional<T, U>::value &&
+ std::is_convertible<U&&, T>::value,
+ bool>::type = false>
+ Optional(Optional<U>&& other) : internal::OptionalBase<T>(std::move(other)) {}
+
+ template <typename U,
+ typename std::enable_if<
+ std::is_constructible<T, U&&>::value &&
+ !internal::IsConvertibleFromOptional<T, U>::value &&
+ !std::is_convertible<U&&, T>::value,
+ bool>::type = false>
+ explicit Optional(Optional<U>&& other)
+ : internal::OptionalBase<T>(std::move(other)) {}
+
+ template <class... Args>
+ constexpr explicit Optional(in_place_t, Args&&... args)
+ : internal::OptionalBase<T>(in_place, std::forward<Args>(args)...) {}
+
+ template <class U,
+ class... Args,
+ class = typename std::enable_if<
+ std::is_constructible<value_type,
+ std::initializer_list<U>&,
+ Args...>::value>::type>
+ constexpr explicit Optional(in_place_t,
+ std::initializer_list<U> il,
+ Args&&... args)
+ : internal::OptionalBase<T>(in_place, il, std::forward<Args>(args)...) {}
+
+ // Forward value constructor. Similar to converting constructors,
+ // conditionally explicit.
+ template <
+ typename U = value_type,
+ typename std::enable_if<
+ std::is_constructible<T, U&&>::value &&
+ !std::is_same<internal::RemoveCvRefT<U>, in_place_t>::value &&
+ !std::is_same<internal::RemoveCvRefT<U>, Optional<T>>::value &&
+ std::is_convertible<U&&, T>::value,
+ bool>::type = false>
+ constexpr Optional(U&& value)
+ : internal::OptionalBase<T>(in_place, std::forward<U>(value)) {}
+
+ template <
+ typename U = value_type,
+ typename std::enable_if<
+ std::is_constructible<T, U&&>::value &&
+ !std::is_same<internal::RemoveCvRefT<U>, in_place_t>::value &&
+ !std::is_same<internal::RemoveCvRefT<U>, Optional<T>>::value &&
+ !std::is_convertible<U&&, T>::value,
+ bool>::type = false>
+ constexpr explicit Optional(U&& value)
+ : internal::OptionalBase<T>(in_place, std::forward<U>(value)) {}
+
+ ~Optional() = default;
+
+ // Defer copy-/move- assign operator implementation to OptionalBase.
+ Optional& operator=(const Optional& other) = default;
+ Optional& operator=(Optional&& other) noexcept(
+ std::is_nothrow_move_assignable<T>::value&&
+ std::is_nothrow_move_constructible<T>::value) = default;
+
+ Optional& operator=(nullopt_t) {
+ FreeIfNeeded();
+ return *this;
+ }
+
+ // Perfect-forwarded assignment.
+ template <typename U>
+ typename std::enable_if<
+ !std::is_same<internal::RemoveCvRefT<U>, Optional<T>>::value &&
+ std::is_constructible<T, U>::value &&
+ std::is_assignable<T&, U>::value &&
+ (!std::is_scalar<T>::value ||
+ !std::is_same<typename std::decay<U>::type, T>::value),
+ Optional&>::type
+ operator=(U&& value) {
+ InitOrAssign(std::forward<U>(value));
+ return *this;
+ }
+
+ // Copy assign the state of other.
+ template <typename U>
+ typename std::enable_if<!internal::IsAssignableFromOptional<T, U>::value &&
+ std::is_constructible<T, const U&>::value &&
+ std::is_assignable<T&, const U&>::value,
+ Optional&>::type
+ operator=(const Optional<U>& other) {
+ CopyAssign(other);
+ return *this;
+ }
+
+ // Move assign the state of other.
+ template <typename U>
+ typename std::enable_if<!internal::IsAssignableFromOptional<T, U>::value &&
+ std::is_constructible<T, U>::value &&
+ std::is_assignable<T&, U>::value,
+ Optional&>::type
+ operator=(Optional<U>&& other) {
+ MoveAssign(std::move(other));
+ return *this;
+ }
+
+ const T* operator->() const {
+ PERFETTO_DCHECK(storage_.is_populated_);
+ return &storage_.value_;
+ }
+
+ T* operator->() {
+ PERFETTO_DCHECK(storage_.is_populated_);
+ return &storage_.value_;
+ }
+
+ const T& operator*() const & {
+ PERFETTO_DCHECK(storage_.is_populated_);
+ return storage_.value_;
+ }
+
+ T& operator*() & {
+ PERFETTO_DCHECK(storage_.is_populated_);
+ return storage_.value_;
+ }
+
+ const T&& operator*() const && {
+ PERFETTO_DCHECK(storage_.is_populated_);
+ return std::move(storage_.value_);
+ }
+
+ T&& operator*() && {
+ PERFETTO_DCHECK(storage_.is_populated_);
+ return std::move(storage_.value_);
+ }
+
+ constexpr explicit operator bool() const { return storage_.is_populated_; }
+
+ constexpr bool has_value() const { return storage_.is_populated_; }
+
+ T& value() & {
+ PERFETTO_CHECK(storage_.is_populated_);
+ return storage_.value_;
+ }
+
+ const T& value() const & {
+ PERFETTO_CHECK(storage_.is_populated_);
+ return storage_.value_;
+ }
+
+ T&& value() && {
+ PERFETTO_CHECK(storage_.is_populated_);
+ return std::move(storage_.value_);
+ }
+
+ const T&& value() const && {
+ PERFETTO_CHECK(storage_.is_populated_);
+ return std::move(storage_.value_);
+ }
+
+ template <class U>
+ constexpr T value_or(U&& default_value) const & {
+ static_assert(std::is_convertible<U, T>::value,
+ "U must be convertible to T");
+ return storage_.is_populated_
+ ? storage_.value_
+ : static_cast<T>(std::forward<U>(default_value));
+ }
+
+ template <class U>
+ T value_or(U&& default_value) && {
+ static_assert(std::is_convertible<U, T>::value,
+ "U must be convertible to T");
+ return storage_.is_populated_
+ ? std::move(storage_.value_)
+ : static_cast<T>(std::forward<U>(default_value));
+ }
+
+ void swap(Optional& other) {
+ if (!storage_.is_populated_ && !other.storage_.is_populated_)
+ return;
+
+ if (storage_.is_populated_ != other.storage_.is_populated_) {
+ if (storage_.is_populated_) {
+ other.storage_.Init(std::move(storage_.value_));
+ FreeIfNeeded();
+ } else {
+ storage_.Init(std::move(other.storage_.value_));
+ other.FreeIfNeeded();
+ }
+ return;
+ }
+
+ PERFETTO_DCHECK(storage_.is_populated_ && other.storage_.is_populated_);
+ using std::swap;
+ swap(**this, *other);
+ }
+
+ void reset() { FreeIfNeeded(); }
+
+ template <class... Args>
+ T& emplace(Args&&... args) {
+ FreeIfNeeded();
+ storage_.Init(std::forward<Args>(args)...);
+ return storage_.value_;
+ }
+
+ template <class U, class... Args>
+ typename std::enable_if<
+ std::is_constructible<T, std::initializer_list<U>&, Args&&...>::value,
+ T&>::type
+ emplace(std::initializer_list<U> il, Args&&... args) {
+ FreeIfNeeded();
+ storage_.Init(il, std::forward<Args>(args)...);
+ return storage_.value_;
+ }
+
+ private:
+ // Accessing template base class's protected member needs explicit
+ // declaration to do so.
+ using internal::OptionalBase<T>::CopyAssign;
+ using internal::OptionalBase<T>::FreeIfNeeded;
+ using internal::OptionalBase<T>::InitOrAssign;
+ using internal::OptionalBase<T>::MoveAssign;
+ using internal::OptionalBase<T>::storage_;
+};
+
+// Here after defines comparation operators. The definition follows
+// http://en.cppreference.com/w/cpp/utility/optional/operator_cmp
+// while bool() casting is replaced by has_value() to meet the chromium
+// style guide.
+template <class T, class U>
+bool operator==(const Optional<T>& lhs, const Optional<U>& rhs) {
+ if (lhs.has_value() != rhs.has_value())
+ return false;
+ if (!lhs.has_value())
+ return true;
+ return *lhs == *rhs;
+}
+
+template <class T, class U>
+bool operator!=(const Optional<T>& lhs, const Optional<U>& rhs) {
+ if (lhs.has_value() != rhs.has_value())
+ return true;
+ if (!lhs.has_value())
+ return false;
+ return *lhs != *rhs;
+}
+
+template <class T, class U>
+bool operator<(const Optional<T>& lhs, const Optional<U>& rhs) {
+ if (!rhs.has_value())
+ return false;
+ if (!lhs.has_value())
+ return true;
+ return *lhs < *rhs;
+}
+
+template <class T, class U>
+bool operator<=(const Optional<T>& lhs, const Optional<U>& rhs) {
+ if (!lhs.has_value())
+ return true;
+ if (!rhs.has_value())
+ return false;
+ return *lhs <= *rhs;
+}
+
+template <class T, class U>
+bool operator>(const Optional<T>& lhs, const Optional<U>& rhs) {
+ if (!lhs.has_value())
+ return false;
+ if (!rhs.has_value())
+ return true;
+ return *lhs > *rhs;
+}
+
+template <class T, class U>
+bool operator>=(const Optional<T>& lhs, const Optional<U>& rhs) {
+ if (!rhs.has_value())
+ return true;
+ if (!lhs.has_value())
+ return false;
+ return *lhs >= *rhs;
+}
+
+template <class T>
+constexpr bool operator==(const Optional<T>& opt, nullopt_t) {
+ return !opt;
+}
+
+template <class T>
+constexpr bool operator==(nullopt_t, const Optional<T>& opt) {
+ return !opt;
+}
+
+template <class T>
+constexpr bool operator!=(const Optional<T>& opt, nullopt_t) {
+ return opt.has_value();
+}
+
+template <class T>
+constexpr bool operator!=(nullopt_t, const Optional<T>& opt) {
+ return opt.has_value();
+}
+
+template <class T>
+constexpr bool operator<(const Optional<T>&, nullopt_t) {
+ return false;
+}
+
+template <class T>
+constexpr bool operator<(nullopt_t, const Optional<T>& opt) {
+ return opt.has_value();
+}
+
+template <class T>
+constexpr bool operator<=(const Optional<T>& opt, nullopt_t) {
+ return !opt;
+}
+
+template <class T>
+constexpr bool operator<=(nullopt_t, const Optional<T>&) {
+ return true;
+}
+
+template <class T>
+constexpr bool operator>(const Optional<T>& opt, nullopt_t) {
+ return opt.has_value();
+}
+
+template <class T>
+constexpr bool operator>(nullopt_t, const Optional<T>&) {
+ return false;
+}
+
+template <class T>
+constexpr bool operator>=(const Optional<T>&, nullopt_t) {
+ return true;
+}
+
+template <class T>
+constexpr bool operator>=(nullopt_t, const Optional<T>& opt) {
+ return !opt;
+}
+
+template <class T, class U>
+constexpr bool operator==(const Optional<T>& opt, const U& value) {
+ return opt.has_value() ? *opt == value : false;
+}
+
+template <class T, class U>
+constexpr bool operator==(const U& value, const Optional<T>& opt) {
+ return opt.has_value() ? value == *opt : false;
+}
+
+template <class T, class U>
+constexpr bool operator!=(const Optional<T>& opt, const U& value) {
+ return opt.has_value() ? *opt != value : true;
+}
+
+template <class T, class U>
+constexpr bool operator!=(const U& value, const Optional<T>& opt) {
+ return opt.has_value() ? value != *opt : true;
+}
+
+template <class T, class U>
+constexpr bool operator<(const Optional<T>& opt, const U& value) {
+ return opt.has_value() ? *opt < value : true;
+}
+
+template <class T, class U>
+constexpr bool operator<(const U& value, const Optional<T>& opt) {
+ return opt.has_value() ? value < *opt : false;
+}
+
+template <class T, class U>
+constexpr bool operator<=(const Optional<T>& opt, const U& value) {
+ return opt.has_value() ? *opt <= value : true;
+}
+
+template <class T, class U>
+constexpr bool operator<=(const U& value, const Optional<T>& opt) {
+ return opt.has_value() ? value <= *opt : false;
+}
+
+template <class T, class U>
+constexpr bool operator>(const Optional<T>& opt, const U& value) {
+ return opt.has_value() ? *opt > value : false;
+}
+
+template <class T, class U>
+constexpr bool operator>(const U& value, const Optional<T>& opt) {
+ return opt.has_value() ? value > *opt : true;
+}
+
+template <class T, class U>
+constexpr bool operator>=(const Optional<T>& opt, const U& value) {
+ return opt.has_value() ? *opt >= value : false;
+}
+
+template <class T, class U>
+constexpr bool operator>=(const U& value, const Optional<T>& opt) {
+ return opt.has_value() ? value >= *opt : true;
+}
+
+template <class T>
+constexpr Optional<typename std::decay<T>::type> make_optional(T&& value) {
+ return Optional<typename std::decay<T>::type>(std::forward<T>(value));
+}
+
+template <class T, class... Args>
+constexpr Optional<T> make_optional(Args&&... args) {
+ return Optional<T>(in_place, std::forward<Args>(args)...);
+}
+
+template <class T, class U, class... Args>
+constexpr Optional<T> make_optional(std::initializer_list<U> il,
+ Args&&... args) {
+ return Optional<T>(in_place, il, std::forward<Args>(args)...);
+}
+
+// Partial specialization for a function template is not allowed. Also, it is
+// not allowed to add overload function to std namespace, while it is allowed
+// to specialize the template in std. Thus, swap() (kind of) overloading is
+// defined in base namespace, instead.
+template <class T>
+typename std::enable_if<std::is_move_constructible<T>::value &&
+ internal::IsSwappable<T>::value>::type
+swap(Optional<T>& lhs, Optional<T>& rhs) {
+ lhs.swap(rhs);
+}
+
+} // namespace base
+} // namespace perfetto
+
+namespace std {
+
+template <class T>
+struct hash<perfetto::base::Optional<T>> {
+ size_t operator()(const perfetto::base::Optional<T>& opt) const {
+ return opt == perfetto::base::nullopt ? 0 : std::hash<T>()(*opt);
+ }
+};
+
+} // namespace std
+
+#endif // INCLUDE_PERFETTO_BASE_OPTIONAL_H_
diff --git a/src/base/BUILD.gn b/src/base/BUILD.gn
index 405874b..3dd1ecb 100644
--- a/src/base/BUILD.gn
+++ b/src/base/BUILD.gn
@@ -137,6 +137,7 @@
deps += [ ":android_task_runner" ]
}
sources = [
+ "optional_unittest.cc",
"paged_memory_unittest.cc",
"scoped_file_unittest.cc",
"string_splitter_unittest.cc",
diff --git a/src/base/optional_unittest.cc b/src/base/optional_unittest.cc
new file mode 100644
index 0000000..f2a26f8
--- /dev/null
+++ b/src/base/optional_unittest.cc
@@ -0,0 +1,2207 @@
+/*
+ * Copyright (C) 2018 The Android Open Source Project
+ *
+ * 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
+ *
+ * http://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.
+ */
+
+// Comparisions of floats is used extensively in this file. Ignore warnings
+// as we want to stay close to Chromium.
+#pragma GCC diagnostic push
+#pragma GCC diagnostic ignored "-Wfloat-equal"
+
+#include <gmock/gmock.h>
+#include <gtest/gtest.h>
+#include <memory>
+#include <set>
+#include <string>
+#include <vector>
+
+#include "perfetto/base/optional.h"
+
+using ::testing::ElementsAre;
+
+namespace perfetto {
+namespace base {
+
+namespace {
+
+// Object used to test complex object with Optional<T> in addition of the move
+// semantics.
+class TestObject {
+ public:
+ enum class State {
+ DEFAULT_CONSTRUCTED,
+ VALUE_CONSTRUCTED,
+ COPY_CONSTRUCTED,
+ MOVE_CONSTRUCTED,
+ MOVED_FROM,
+ COPY_ASSIGNED,
+ MOVE_ASSIGNED,
+ SWAPPED,
+ };
+
+ TestObject() : foo_(0), bar_(0.0), state_(State::DEFAULT_CONSTRUCTED) {}
+
+ TestObject(int foo, double bar)
+ : foo_(foo), bar_(bar), state_(State::VALUE_CONSTRUCTED) {}
+
+ TestObject(const TestObject& other)
+ : foo_(other.foo_),
+ bar_(other.bar_),
+ state_(State::COPY_CONSTRUCTED),
+ move_ctors_count_(other.move_ctors_count_) {}
+
+ TestObject(TestObject&& other)
+ : foo_(std::move(other.foo_)),
+ bar_(std::move(other.bar_)),
+ state_(State::MOVE_CONSTRUCTED),
+ move_ctors_count_(other.move_ctors_count_ + 1) {
+ other.state_ = State::MOVED_FROM;
+ }
+
+ TestObject& operator=(const TestObject& other) {
+ foo_ = other.foo_;
+ bar_ = other.bar_;
+ state_ = State::COPY_ASSIGNED;
+ move_ctors_count_ = other.move_ctors_count_;
+ return *this;
+ }
+
+ TestObject& operator=(TestObject&& other) {
+ foo_ = other.foo_;
+ bar_ = other.bar_;
+ state_ = State::MOVE_ASSIGNED;
+ move_ctors_count_ = other.move_ctors_count_;
+ other.state_ = State::MOVED_FROM;
+ return *this;
+ }
+
+ void Swap(TestObject* other) {
+ using std::swap;
+ swap(foo_, other->foo_);
+ swap(bar_, other->bar_);
+ swap(move_ctors_count_, other->move_ctors_count_);
+ state_ = State::SWAPPED;
+ other->state_ = State::SWAPPED;
+ }
+
+ bool operator==(const TestObject& other) const {
+ return std::tie(foo_, bar_) == std::tie(other.foo_, other.bar_);
+ }
+
+ bool operator!=(const TestObject& other) const { return !(*this == other); }
+
+ int foo() const { return foo_; }
+ State state() const { return state_; }
+ int move_ctors_count() const { return move_ctors_count_; }
+
+ private:
+ int foo_;
+ double bar_;
+ State state_;
+ int move_ctors_count_ = 0;
+};
+
+// Implementing Swappable concept.
+void swap(TestObject& lhs, TestObject& rhs) {
+ lhs.Swap(&rhs);
+}
+
+class NonTriviallyDestructible {
+ ~NonTriviallyDestructible() {}
+};
+
+class DeletedDefaultConstructor {
+ public:
+ DeletedDefaultConstructor() = delete;
+ DeletedDefaultConstructor(int foo) : foo_(foo) {}
+
+ int foo() const { return foo_; }
+
+ private:
+ int foo_;
+};
+
+class DeletedCopy {
+ public:
+ explicit DeletedCopy(int foo) : foo_(foo) {}
+ DeletedCopy(const DeletedCopy&) = delete;
+ DeletedCopy(DeletedCopy&&) = default;
+
+ DeletedCopy& operator=(const DeletedCopy&) = delete;
+ DeletedCopy& operator=(DeletedCopy&&) = default;
+
+ int foo() const { return foo_; }
+
+ private:
+ int foo_;
+};
+
+class DeletedMove {
+ public:
+ explicit DeletedMove(int foo) : foo_(foo) {}
+ DeletedMove(const DeletedMove&) = default;
+ DeletedMove(DeletedMove&&) = delete;
+
+ DeletedMove& operator=(const DeletedMove&) = default;
+ DeletedMove& operator=(DeletedMove&&) = delete;
+
+ int foo() const { return foo_; }
+
+ private:
+ int foo_;
+};
+
+class NonTriviallyDestructibleDeletedCopyConstructor {
+ public:
+ explicit NonTriviallyDestructibleDeletedCopyConstructor(int foo)
+ : foo_(foo) {}
+ NonTriviallyDestructibleDeletedCopyConstructor(
+ const NonTriviallyDestructibleDeletedCopyConstructor&) = delete;
+ NonTriviallyDestructibleDeletedCopyConstructor(
+ NonTriviallyDestructibleDeletedCopyConstructor&&) = default;
+
+ ~NonTriviallyDestructibleDeletedCopyConstructor() {}
+
+ int foo() const { return foo_; }
+
+ private:
+ int foo_;
+};
+
+class DeleteNewOperators {
+ public:
+ void* operator new(size_t) = delete;
+ void* operator new(size_t, void*) = delete;
+ void* operator new[](size_t) = delete;
+ void* operator new[](size_t, void*) = delete;
+};
+
+} // anonymous namespace
+
+static_assert(std::is_trivially_destructible<Optional<int>>::value,
+ "OptionalIsTriviallyDestructible");
+
+static_assert(
+ !std::is_trivially_destructible<Optional<NonTriviallyDestructible>>::value,
+ "OptionalIsTriviallyDestructible");
+
+static_assert(sizeof(Optional<int>) == sizeof(internal::OptionalBase<int>),
+ "internal::{Copy,Move}{Constructible,Assignable} structs "
+ "should be 0-sized");
+
+TEST(OptionalTest, DefaultConstructor) {
+ {
+ constexpr Optional<float> o;
+ EXPECT_FALSE(o);
+ }
+
+ {
+ Optional<std::string> o;
+ EXPECT_FALSE(o);
+ }
+
+ {
+ Optional<TestObject> o;
+ EXPECT_FALSE(o);
+ }
+}
+
+TEST(OptionalTest, CopyConstructor) {
+ {
+ constexpr Optional<float> first(0.1f);
+ constexpr Optional<float> other(first);
+
+ EXPECT_TRUE(other);
+ EXPECT_EQ(other.value(), 0.1f);
+ EXPECT_EQ(first, other);
+ }
+
+ {
+ Optional<std::string> first("foo");
+ Optional<std::string> other(first);
+
+ EXPECT_TRUE(other);
+ EXPECT_EQ(other.value(), "foo");
+ EXPECT_EQ(first, other);
+ }
+
+ {
+ const Optional<std::string> first("foo");
+ Optional<std::string> other(first);
+
+ EXPECT_TRUE(other);
+ EXPECT_EQ(other.value(), "foo");
+ EXPECT_EQ(first, other);
+ }
+
+ {
+ Optional<TestObject> first(TestObject(3, 0.1));
+ Optional<TestObject> other(first);
+
+ EXPECT_TRUE(!!other);
+ EXPECT_TRUE(other.value() == TestObject(3, 0.1));
+ EXPECT_TRUE(first == other);
+ }
+}
+
+TEST(OptionalTest, ValueConstructor) {
+ {
+ constexpr float value = 0.1f;
+ constexpr Optional<float> o(value);
+
+ EXPECT_TRUE(o);
+ EXPECT_EQ(value, o.value());
+ }
+
+ {
+ std::string value("foo");
+ Optional<std::string> o(value);
+
+ EXPECT_TRUE(o);
+ EXPECT_EQ(value, o.value());
+ }
+
+ {
+ TestObject value(3, 0.1);
+ Optional<TestObject> o(value);
+
+ EXPECT_TRUE(o);
+ EXPECT_EQ(TestObject::State::COPY_CONSTRUCTED, o->state());
+ EXPECT_EQ(value, o.value());
+ }
+}
+
+TEST(OptionalTest, MoveConstructor) {
+ {
+ constexpr Optional<float> first(0.1f);
+ constexpr Optional<float> second(std::move(first));
+
+ EXPECT_TRUE(second.has_value());
+ EXPECT_EQ(second.value(), 0.1f);
+
+ EXPECT_TRUE(first.has_value());
+ }
+
+ {
+ Optional<std::string> first("foo");
+ Optional<std::string> second(std::move(first));
+
+ EXPECT_TRUE(second.has_value());
+ EXPECT_EQ("foo", second.value());
+
+ EXPECT_TRUE(first.has_value());
+ }
+
+ {
+ Optional<TestObject> first(TestObject(3, 0.1));
+ Optional<TestObject> second(std::move(first));
+
+ EXPECT_TRUE(second.has_value());
+ EXPECT_EQ(TestObject::State::MOVE_CONSTRUCTED, second->state());
+ EXPECT_TRUE(TestObject(3, 0.1) == second.value());
+
+ EXPECT_TRUE(first.has_value());
+ EXPECT_EQ(TestObject::State::MOVED_FROM, first->state());
+ }
+
+ // Even if copy constructor is deleted, move constructor needs to work.
+ // Note that it couldn't be constexpr.
+ {
+ Optional<DeletedCopy> first(in_place, 42);
+ Optional<DeletedCopy> second(std::move(first));
+
+ EXPECT_TRUE(second.has_value());
+ EXPECT_EQ(42, second->foo());
+
+ EXPECT_TRUE(first.has_value());
+ }
+
+ {
+ Optional<DeletedMove> first(in_place, 42);
+ Optional<DeletedMove> second(std::move(first));
+
+ EXPECT_TRUE(second.has_value());
+ EXPECT_EQ(42, second->foo());
+
+ EXPECT_TRUE(first.has_value());
+ }
+
+ {
+ Optional<NonTriviallyDestructibleDeletedCopyConstructor> first(in_place,
+ 42);
+ Optional<NonTriviallyDestructibleDeletedCopyConstructor> second(
+ std::move(first));
+
+ EXPECT_TRUE(second.has_value());
+ EXPECT_EQ(42, second->foo());
+
+ EXPECT_TRUE(first.has_value());
+ }
+}
+
+TEST(OptionalTest, MoveValueConstructor) {
+ {
+ constexpr float value = 0.1f;
+ constexpr Optional<float> o(std::move(value));
+
+ EXPECT_TRUE(o);
+ EXPECT_EQ(0.1f, o.value());
+ }
+
+ {
+ float value = 0.1f;
+ Optional<float> o(std::move(value));
+
+ EXPECT_TRUE(o);
+ EXPECT_EQ(0.1f, o.value());
+ }
+
+ {
+ std::string value("foo");
+ Optional<std::string> o(std::move(value));
+
+ EXPECT_TRUE(o);
+ EXPECT_EQ("foo", o.value());
+ }
+
+ {
+ TestObject value(3, 0.1);
+ Optional<TestObject> o(std::move(value));
+
+ EXPECT_TRUE(o);
+ EXPECT_EQ(TestObject::State::MOVE_CONSTRUCTED, o->state());
+ EXPECT_EQ(TestObject(3, 0.1), o.value());
+ }
+}
+
+TEST(OptionalTest, ConvertingCopyConstructor) {
+ {
+ Optional<int> first(1);
+ Optional<double> second(first);
+ EXPECT_TRUE(second.has_value());
+ EXPECT_EQ(1.0, second.value());
+ }
+
+ // Make sure explicit is not marked for convertible case.
+ {
+ Optional<int> o(1);
+ ignore_result<Optional<double>>(o);
+ }
+}
+
+TEST(OptionalTest, ConvertingMoveConstructor) {
+ {
+ Optional<int> first(1);
+ Optional<double> second(std::move(first));
+ EXPECT_TRUE(second.has_value());
+ EXPECT_EQ(1.0, second.value());
+ }
+
+ // Make sure explicit is not marked for convertible case.
+ {
+ Optional<int> o(1);
+ ignore_result<Optional<double>>(std::move(o));
+ }
+
+ {
+ class Test1 {
+ public:
+ explicit Test1(int foo) : foo_(foo) {}
+
+ int foo() const { return foo_; }
+
+ private:
+ int foo_;
+ };
+
+ // Not copyable but convertible from Test1.
+ class Test2 {
+ public:
+ Test2(const Test2&) = delete;
+ explicit Test2(Test1&& other) : bar_(other.foo()) {}
+
+ double bar() const { return bar_; }
+
+ private:
+ double bar_;
+ };
+
+ Optional<Test1> first(in_place, 42);
+ Optional<Test2> second(std::move(first));
+ EXPECT_TRUE(second.has_value());
+ EXPECT_EQ(42.0, second->bar());
+ }
+}
+
+TEST(OptionalTest, ConstructorForwardArguments) {
+ {
+ constexpr Optional<float> a(base::in_place, 0.1f);
+ EXPECT_TRUE(a);
+ EXPECT_EQ(0.1f, a.value());
+ }
+
+ {
+ Optional<float> a(base::in_place, 0.1f);
+ EXPECT_TRUE(a);
+ EXPECT_EQ(0.1f, a.value());
+ }
+
+ {
+ Optional<std::string> a(base::in_place, "foo");
+ EXPECT_TRUE(a);
+ EXPECT_EQ("foo", a.value());
+ }
+
+ {
+ Optional<TestObject> a(base::in_place, 0, 0.1);
+ EXPECT_TRUE(!!a);
+ EXPECT_TRUE(TestObject(0, 0.1) == a.value());
+ }
+}
+
+TEST(OptionalTest, ConstructorForwardInitListAndArguments) {
+ {
+ Optional<std::vector<int>> opt(in_place, {3, 1});
+ EXPECT_TRUE(opt);
+ EXPECT_THAT(*opt, ElementsAre(3, 1));
+ EXPECT_EQ(2u, opt->size());
+ }
+
+ {
+ Optional<std::vector<int>> opt(in_place, {3, 1}, std::allocator<int>());
+ EXPECT_TRUE(opt);
+ EXPECT_THAT(*opt, ElementsAre(3, 1));
+ EXPECT_EQ(2u, opt->size());
+ }
+}
+
+TEST(OptionalTest, ForwardConstructor) {
+ {
+ Optional<double> a(1);
+ EXPECT_TRUE(a.has_value());
+ EXPECT_EQ(1.0, a.value());
+ }
+
+ // Test that default type of 'U' is value_type.
+ {
+ struct TestData {
+ int a;
+ double b;
+ bool c;
+ };
+
+ Optional<TestData> a({1, 2.0, true});
+ EXPECT_TRUE(a.has_value());
+ EXPECT_EQ(1, a->a);
+ EXPECT_EQ(2.0, a->b);
+ EXPECT_TRUE(a->c);
+ }
+
+ // If T has a constructor with a param Optional<U>, and another ctor with a
+ // param U, then T(Optional<U>) should be used for Optional<T>(Optional<U>)
+ // constructor.
+ {
+ enum class ParamType {
+ DEFAULT_CONSTRUCTED,
+ COPY_CONSTRUCTED,
+ MOVE_CONSTRUCTED,
+ INT,
+ IN_PLACE,
+ OPTIONAL_INT,
+ };
+ struct Test {
+ Test() : param_type(ParamType::DEFAULT_CONSTRUCTED) {}
+ Test(const Test&) : param_type(ParamType::COPY_CONSTRUCTED) {}
+ Test(Test&&) : param_type(ParamType::MOVE_CONSTRUCTED) {}
+ explicit Test(int) : param_type(ParamType::INT) {}
+ explicit Test(in_place_t) : param_type(ParamType::IN_PLACE) {}
+ explicit Test(Optional<int>) : param_type(ParamType::OPTIONAL_INT) {}
+
+ ParamType param_type;
+ };
+
+ // Overload resolution with copy-conversion constructor.
+ {
+ const Optional<int> arg(in_place, 1);
+ Optional<Test> testee(arg);
+ EXPECT_EQ(ParamType::OPTIONAL_INT, testee->param_type);
+ }
+
+ // Overload resolution with move conversion constructor.
+ {
+ Optional<Test> testee(Optional<int>(in_place, 1));
+ EXPECT_EQ(ParamType::OPTIONAL_INT, testee->param_type);
+ }
+
+ // Default constructor should be used.
+ {
+ Optional<Test> testee(in_place);
+ EXPECT_EQ(ParamType::DEFAULT_CONSTRUCTED, testee->param_type);
+ }
+ }
+
+ {
+ struct Test {
+ Test(int) {} // NOLINT(runtime/explicit)
+ };
+ // If T is convertible from U, it is not marked as explicit.
+ static_assert(std::is_convertible<int, Test>::value,
+ "Int should be convertible to Test.");
+ ([](Optional<Test>) {})(1);
+ }
+}
+
+TEST(OptionalTest, NulloptConstructor) {
+ constexpr Optional<int> a(base::nullopt);
+ EXPECT_FALSE(a);
+}
+
+TEST(OptionalTest, AssignValue) {
+ {
+ Optional<float> a;
+ EXPECT_FALSE(a);
+ a = 0.1f;
+ EXPECT_TRUE(a);
+
+ Optional<float> b(0.1f);
+ EXPECT_TRUE(a == b);
+ }
+
+ {
+ Optional<std::string> a;
+ EXPECT_FALSE(a);
+ a = std::string("foo");
+ EXPECT_TRUE(a);
+
+ Optional<std::string> b(std::string("foo"));
+ EXPECT_EQ(a, b);
+ }
+
+ {
+ Optional<TestObject> a;
+ EXPECT_FALSE(!!a);
+ a = TestObject(3, 0.1);
+ EXPECT_TRUE(!!a);
+
+ Optional<TestObject> b(TestObject(3, 0.1));
+ EXPECT_TRUE(a == b);
+ }
+
+ {
+ Optional<TestObject> a = TestObject(4, 1.0);
+ EXPECT_TRUE(!!a);
+ a = TestObject(3, 0.1);
+ EXPECT_TRUE(!!a);
+
+ Optional<TestObject> b(TestObject(3, 0.1));
+ EXPECT_TRUE(a == b);
+ }
+}
+
+TEST(OptionalTest, AssignObject) {
+ {
+ Optional<float> a;
+ Optional<float> b(0.1f);
+ a = b;
+
+ EXPECT_TRUE(a);
+ EXPECT_EQ(a.value(), 0.1f);
+ EXPECT_EQ(a, b);
+ }
+
+ {
+ Optional<std::string> a;
+ Optional<std::string> b("foo");
+ a = b;
+
+ EXPECT_TRUE(a);
+ EXPECT_EQ(a.value(), "foo");
+ EXPECT_EQ(a, b);
+ }
+
+ {
+ Optional<TestObject> a;
+ Optional<TestObject> b(TestObject(3, 0.1));
+ a = b;
+
+ EXPECT_TRUE(!!a);
+ EXPECT_TRUE(a.value() == TestObject(3, 0.1));
+ EXPECT_TRUE(a == b);
+ }
+
+ {
+ Optional<TestObject> a(TestObject(4, 1.0));
+ Optional<TestObject> b(TestObject(3, 0.1));
+ a = b;
+
+ EXPECT_TRUE(!!a);
+ EXPECT_TRUE(a.value() == TestObject(3, 0.1));
+ EXPECT_TRUE(a == b);
+ }
+
+ {
+ Optional<DeletedMove> a(in_place, 42);
+ Optional<DeletedMove> b;
+ b = a;
+
+ EXPECT_TRUE(!!a);
+ EXPECT_TRUE(!!b);
+ EXPECT_EQ(a->foo(), b->foo());
+ }
+
+ {
+ Optional<DeletedMove> a(in_place, 42);
+ Optional<DeletedMove> b(in_place, 1);
+ b = a;
+
+ EXPECT_TRUE(!!a);
+ EXPECT_TRUE(!!b);
+ EXPECT_EQ(a->foo(), b->foo());
+ }
+
+ // Converting assignment.
+ {
+ Optional<int> a(in_place, 1);
+ Optional<double> b;
+ b = a;
+
+ EXPECT_TRUE(!!a);
+ EXPECT_TRUE(!!b);
+ EXPECT_EQ(1, a.value());
+ EXPECT_EQ(1.0, b.value());
+ }
+
+ {
+ Optional<int> a(in_place, 42);
+ Optional<double> b(in_place, 1);
+ b = a;
+
+ EXPECT_TRUE(!!a);
+ EXPECT_TRUE(!!b);
+ EXPECT_EQ(42, a.value());
+ EXPECT_EQ(42.0, b.value());
+ }
+
+ {
+ Optional<int> a;
+ Optional<double> b(in_place, 1);
+ b = a;
+ EXPECT_FALSE(!!a);
+ EXPECT_FALSE(!!b);
+ }
+}
+
+TEST(OptionalTest, AssignObject_rvalue) {
+ {
+ Optional<float> a;
+ Optional<float> b(0.1f);
+ a = std::move(b);
+
+ EXPECT_TRUE(a);
+ EXPECT_TRUE(b);
+ EXPECT_EQ(0.1f, a.value());
+ }
+
+ {
+ Optional<std::string> a;
+ Optional<std::string> b("foo");
+ a = std::move(b);
+
+ EXPECT_TRUE(a);
+ EXPECT_TRUE(b);
+ EXPECT_EQ("foo", a.value());
+ }
+
+ {
+ Optional<TestObject> a;
+ Optional<TestObject> b(TestObject(3, 0.1));
+ a = std::move(b);
+
+ EXPECT_TRUE(!!a);
+ EXPECT_TRUE(!!b);
+ EXPECT_TRUE(TestObject(3, 0.1) == a.value());
+
+ EXPECT_EQ(TestObject::State::MOVE_CONSTRUCTED, a->state());
+ EXPECT_EQ(TestObject::State::MOVED_FROM, b->state());
+ }
+
+ {
+ Optional<TestObject> a(TestObject(4, 1.0));
+ Optional<TestObject> b(TestObject(3, 0.1));
+ a = std::move(b);
+
+ EXPECT_TRUE(!!a);
+ EXPECT_TRUE(!!b);
+ EXPECT_TRUE(TestObject(3, 0.1) == a.value());
+
+ EXPECT_EQ(TestObject::State::MOVE_ASSIGNED, a->state());
+ EXPECT_EQ(TestObject::State::MOVED_FROM, b->state());
+ }
+
+ {
+ Optional<DeletedMove> a(in_place, 42);
+ Optional<DeletedMove> b;
+ b = std::move(a);
+
+ EXPECT_TRUE(!!a);
+ EXPECT_TRUE(!!b);
+ EXPECT_EQ(42, b->foo());
+ }
+
+ {
+ Optional<DeletedMove> a(in_place, 42);
+ Optional<DeletedMove> b(in_place, 1);
+ b = std::move(a);
+
+ EXPECT_TRUE(!!a);
+ EXPECT_TRUE(!!b);
+ EXPECT_EQ(42, b->foo());
+ }
+
+ // Converting assignment.
+ {
+ Optional<int> a(in_place, 1);
+ Optional<double> b;
+ b = std::move(a);
+
+ EXPECT_TRUE(!!a);
+ EXPECT_TRUE(!!b);
+ EXPECT_EQ(1.0, b.value());
+ }
+
+ {
+ Optional<int> a(in_place, 42);
+ Optional<double> b(in_place, 1);
+ b = std::move(a);
+
+ EXPECT_TRUE(!!a);
+ EXPECT_TRUE(!!b);
+ EXPECT_EQ(42.0, b.value());
+ }
+
+ {
+ Optional<int> a;
+ Optional<double> b(in_place, 1);
+ b = std::move(a);
+
+ EXPECT_FALSE(!!a);
+ EXPECT_FALSE(!!b);
+ }
+}
+
+TEST(OptionalTest, AssignNull) {
+ {
+ Optional<float> a(0.1f);
+ Optional<float> b(0.2f);
+ a = base::nullopt;
+ b = base::nullopt;
+ EXPECT_EQ(a, b);
+ }
+
+ {
+ Optional<std::string> a("foo");
+ Optional<std::string> b("bar");
+ a = base::nullopt;
+ b = base::nullopt;
+ EXPECT_EQ(a, b);
+ }
+
+ {
+ Optional<TestObject> a(TestObject(3, 0.1));
+ Optional<TestObject> b(TestObject(4, 1.0));
+ a = base::nullopt;
+ b = base::nullopt;
+ EXPECT_TRUE(a == b);
+ }
+}
+
+TEST(OptionalTest, AssignOverload) {
+ struct Test1 {
+ enum class State {
+ CONSTRUCTED,
+ MOVED,
+ };
+ State state = State::CONSTRUCTED;
+ };
+
+ // Here, Optional<Test2> can be assigned from Optioanl<Test1>.
+ // In case of move, marks MOVED to Test1 instance.
+ struct Test2 {
+ enum class State {
+ DEFAULT_CONSTRUCTED,
+ COPY_CONSTRUCTED_FROM_TEST1,
+ MOVE_CONSTRUCTED_FROM_TEST1,
+ COPY_ASSIGNED_FROM_TEST1,
+ MOVE_ASSIGNED_FROM_TEST1,
+ };
+
+ Test2() = default;
+ explicit Test2(const Test1&) : state(State::COPY_CONSTRUCTED_FROM_TEST1) {}
+ explicit Test2(Test1&& test1) : state(State::MOVE_CONSTRUCTED_FROM_TEST1) {
+ test1.state = Test1::State::MOVED;
+ }
+ Test2& operator=(const Test1&) {
+ state = State::COPY_ASSIGNED_FROM_TEST1;
+ return *this;
+ }
+ Test2& operator=(Test1&& test1) {
+ state = State::MOVE_ASSIGNED_FROM_TEST1;
+ test1.state = Test1::State::MOVED;
+ return *this;
+ }
+
+ State state = State::DEFAULT_CONSTRUCTED;
+ };
+
+ {
+ Optional<Test1> a(in_place);
+ Optional<Test2> b;
+
+ b = a;
+ EXPECT_TRUE(!!a);
+ EXPECT_TRUE(!!b);
+ EXPECT_EQ(Test1::State::CONSTRUCTED, a->state);
+ EXPECT_EQ(Test2::State::COPY_CONSTRUCTED_FROM_TEST1, b->state);
+ }
+
+ {
+ Optional<Test1> a(in_place);
+ Optional<Test2> b(in_place);
+
+ b = a;
+ EXPECT_TRUE(!!a);
+ EXPECT_TRUE(!!b);
+ EXPECT_EQ(Test1::State::CONSTRUCTED, a->state);
+ EXPECT_EQ(Test2::State::COPY_ASSIGNED_FROM_TEST1, b->state);
+ }
+
+ {
+ Optional<Test1> a(in_place);
+ Optional<Test2> b;
+
+ b = std::move(a);
+ EXPECT_TRUE(!!a);
+ EXPECT_TRUE(!!b);
+ EXPECT_EQ(Test1::State::MOVED, a->state);
+ EXPECT_EQ(Test2::State::MOVE_CONSTRUCTED_FROM_TEST1, b->state);
+ }
+
+ {
+ Optional<Test1> a(in_place);
+ Optional<Test2> b(in_place);
+
+ b = std::move(a);
+ EXPECT_TRUE(!!a);
+ EXPECT_TRUE(!!b);
+ EXPECT_EQ(Test1::State::MOVED, a->state);
+ EXPECT_EQ(Test2::State::MOVE_ASSIGNED_FROM_TEST1, b->state);
+ }
+
+ // Similar to Test2, but Test3 also has copy/move ctor and assign operators
+ // from Optional<Test1>, too. In this case, for a = b where a is
+ // Optional<Test3> and b is Optional<Test1>,
+ // Optional<T>::operator=(U&&) where U is Optional<Test1> should be used
+ // rather than Optional<T>::operator=(Optional<U>&&) where U is Test1.
+ struct Test3 {
+ enum class State {
+ DEFAULT_CONSTRUCTED,
+ COPY_CONSTRUCTED_FROM_TEST1,
+ MOVE_CONSTRUCTED_FROM_TEST1,
+ COPY_CONSTRUCTED_FROM_OPTIONAL_TEST1,
+ MOVE_CONSTRUCTED_FROM_OPTIONAL_TEST1,
+ COPY_ASSIGNED_FROM_TEST1,
+ MOVE_ASSIGNED_FROM_TEST1,
+ COPY_ASSIGNED_FROM_OPTIONAL_TEST1,
+ MOVE_ASSIGNED_FROM_OPTIONAL_TEST1,
+ };
+
+ Test3() = default;
+ explicit Test3(const Test1&) : state(State::COPY_CONSTRUCTED_FROM_TEST1) {}
+ explicit Test3(Test1&& test1) : state(State::MOVE_CONSTRUCTED_FROM_TEST1) {
+ test1.state = Test1::State::MOVED;
+ }
+ explicit Test3(const Optional<Test1>&)
+ : state(State::COPY_CONSTRUCTED_FROM_OPTIONAL_TEST1) {}
+ explicit Test3(Optional<Test1>&& test1)
+ : state(State::MOVE_CONSTRUCTED_FROM_OPTIONAL_TEST1) {
+ // In the following senarios, given |test1| should always have value.
+ PERFETTO_DCHECK(test1.has_value());
+ test1->state = Test1::State::MOVED;
+ }
+ Test3& operator=(const Test1&) {
+ state = State::COPY_ASSIGNED_FROM_TEST1;
+ return *this;
+ }
+ Test3& operator=(Test1&& test1) {
+ state = State::MOVE_ASSIGNED_FROM_TEST1;
+ test1.state = Test1::State::MOVED;
+ return *this;
+ }
+ Test3& operator=(const Optional<Test1>&) {
+ state = State::COPY_ASSIGNED_FROM_OPTIONAL_TEST1;
+ return *this;
+ }
+ Test3& operator=(Optional<Test1>&& test1) {
+ state = State::MOVE_ASSIGNED_FROM_OPTIONAL_TEST1;
+ // In the following senarios, given |test1| should always have value.
+ PERFETTO_DCHECK(test1.has_value());
+ test1->state = Test1::State::MOVED;
+ return *this;
+ }
+
+ State state = State::DEFAULT_CONSTRUCTED;
+ };
+
+ {
+ Optional<Test1> a(in_place);
+ Optional<Test3> b;
+
+ b = a;
+ EXPECT_TRUE(!!a);
+ EXPECT_TRUE(!!b);
+ EXPECT_EQ(Test1::State::CONSTRUCTED, a->state);
+ EXPECT_EQ(Test3::State::COPY_CONSTRUCTED_FROM_OPTIONAL_TEST1, b->state);
+ }
+
+ {
+ Optional<Test1> a(in_place);
+ Optional<Test3> b(in_place);
+
+ b = a;
+ EXPECT_TRUE(!!a);
+ EXPECT_TRUE(!!b);
+ EXPECT_EQ(Test1::State::CONSTRUCTED, a->state);
+ EXPECT_EQ(Test3::State::COPY_ASSIGNED_FROM_OPTIONAL_TEST1, b->state);
+ }
+
+ {
+ Optional<Test1> a(in_place);
+ Optional<Test3> b;
+
+ b = std::move(a);
+ EXPECT_TRUE(!!a);
+ EXPECT_TRUE(!!b);
+ EXPECT_EQ(Test1::State::MOVED, a->state);
+ EXPECT_EQ(Test3::State::MOVE_CONSTRUCTED_FROM_OPTIONAL_TEST1, b->state);
+ }
+
+ {
+ Optional<Test1> a(in_place);
+ Optional<Test3> b(in_place);
+
+ b = std::move(a);
+ EXPECT_TRUE(!!a);
+ EXPECT_TRUE(!!b);
+ EXPECT_EQ(Test1::State::MOVED, a->state);
+ EXPECT_EQ(Test3::State::MOVE_ASSIGNED_FROM_OPTIONAL_TEST1, b->state);
+ }
+}
+
+TEST(OptionalTest, OperatorStar) {
+ {
+ Optional<float> a(0.1f);
+ EXPECT_EQ(a.value(), *a);
+ }
+
+ {
+ Optional<std::string> a("foo");
+ EXPECT_EQ(a.value(), *a);
+ }
+
+ {
+ Optional<TestObject> a(TestObject(3, 0.1));
+ EXPECT_EQ(a.value(), *a);
+ }
+}
+
+TEST(OptionalTest, OperatorStar_rvalue) {
+ EXPECT_EQ(0.1f, *Optional<float>(0.1f));
+ EXPECT_EQ(std::string("foo"), *Optional<std::string>("foo"));
+ EXPECT_TRUE(TestObject(3, 0.1) == *Optional<TestObject>(TestObject(3, 0.1)));
+}
+
+TEST(OptionalTest, OperatorArrow) {
+ Optional<TestObject> a(TestObject(3, 0.1));
+ EXPECT_EQ(a->foo(), 3);
+}
+
+TEST(OptionalTest, Value_rvalue) {
+ EXPECT_EQ(0.1f, Optional<float>(0.1f).value());
+ EXPECT_EQ(std::string("foo"), Optional<std::string>("foo").value());
+ EXPECT_TRUE(TestObject(3, 0.1) ==
+ Optional<TestObject>(TestObject(3, 0.1)).value());
+}
+
+TEST(OptionalTest, ValueOr) {
+ {
+ Optional<float> a;
+ EXPECT_EQ(0.0f, a.value_or(0.0f));
+
+ a = 0.1f;
+ EXPECT_EQ(0.1f, a.value_or(0.0f));
+
+ a = base::nullopt;
+ EXPECT_EQ(0.0f, a.value_or(0.0f));
+ }
+
+ // value_or() can be constexpr.
+ {
+ constexpr Optional<int> a(in_place, 1);
+ constexpr int value = a.value_or(10);
+ EXPECT_EQ(1, value);
+ }
+ {
+ constexpr Optional<int> a;
+ constexpr int value = a.value_or(10);
+ EXPECT_EQ(10, value);
+ }
+
+ {
+ Optional<std::string> a;
+ EXPECT_EQ("bar", a.value_or("bar"));
+
+ a = std::string("foo");
+ EXPECT_EQ(std::string("foo"), a.value_or("bar"));
+
+ a = base::nullopt;
+ EXPECT_EQ(std::string("bar"), a.value_or("bar"));
+ }
+
+ {
+ Optional<TestObject> a;
+ EXPECT_TRUE(a.value_or(TestObject(1, 0.3)) == TestObject(1, 0.3));
+
+ a = TestObject(3, 0.1);
+ EXPECT_TRUE(a.value_or(TestObject(1, 0.3)) == TestObject(3, 0.1));
+
+ a = base::nullopt;
+ EXPECT_TRUE(a.value_or(TestObject(1, 0.3)) == TestObject(1, 0.3));
+ }
+}
+
+TEST(OptionalTest, Swap_bothNoValue) {
+ Optional<TestObject> a, b;
+ a.swap(b);
+
+ EXPECT_FALSE(a);
+ EXPECT_FALSE(b);
+ EXPECT_TRUE(TestObject(42, 0.42) == a.value_or(TestObject(42, 0.42)));
+ EXPECT_TRUE(TestObject(42, 0.42) == b.value_or(TestObject(42, 0.42)));
+}
+
+TEST(OptionalTest, Swap_inHasValue) {
+ Optional<TestObject> a(TestObject(1, 0.3));
+ Optional<TestObject> b;
+ a.swap(b);
+
+ EXPECT_FALSE(a);
+
+ EXPECT_TRUE(!!b);
+ EXPECT_TRUE(TestObject(42, 0.42) == a.value_or(TestObject(42, 0.42)));
+ EXPECT_TRUE(TestObject(1, 0.3) == b.value_or(TestObject(42, 0.42)));
+}
+
+TEST(OptionalTest, Swap_outHasValue) {
+ Optional<TestObject> a;
+ Optional<TestObject> b(TestObject(1, 0.3));
+ a.swap(b);
+
+ EXPECT_TRUE(!!a);
+ EXPECT_FALSE(!!b);
+ EXPECT_TRUE(TestObject(1, 0.3) == a.value_or(TestObject(42, 0.42)));
+ EXPECT_TRUE(TestObject(42, 0.42) == b.value_or(TestObject(42, 0.42)));
+}
+
+TEST(OptionalTest, Swap_bothValue) {
+ Optional<TestObject> a(TestObject(0, 0.1));
+ Optional<TestObject> b(TestObject(1, 0.3));
+ a.swap(b);
+
+ EXPECT_TRUE(!!a);
+ EXPECT_TRUE(!!b);
+ EXPECT_TRUE(TestObject(1, 0.3) == a.value_or(TestObject(42, 0.42)));
+ EXPECT_TRUE(TestObject(0, 0.1) == b.value_or(TestObject(42, 0.42)));
+ EXPECT_EQ(TestObject::State::SWAPPED, a->state());
+ EXPECT_EQ(TestObject::State::SWAPPED, b->state());
+}
+
+TEST(OptionalTest, Emplace) {
+ {
+ Optional<float> a(0.1f);
+ EXPECT_EQ(0.3f, a.emplace(0.3f));
+
+ EXPECT_TRUE(a);
+ EXPECT_EQ(0.3f, a.value());
+ }
+
+ {
+ Optional<std::string> a("foo");
+ EXPECT_EQ("bar", a.emplace("bar"));
+
+ EXPECT_TRUE(a);
+ EXPECT_EQ("bar", a.value());
+ }
+
+ {
+ Optional<TestObject> a(TestObject(0, 0.1));
+ EXPECT_EQ(TestObject(1, 0.2), a.emplace(TestObject(1, 0.2)));
+
+ EXPECT_TRUE(!!a);
+ EXPECT_TRUE(TestObject(1, 0.2) == a.value());
+ }
+
+ {
+ Optional<std::vector<int>> a;
+ auto& ref = a.emplace({2, 3});
+ static_assert(std::is_same<std::vector<int>&, decltype(ref)>::value, "");
+ EXPECT_TRUE(a);
+ EXPECT_THAT(*a, ElementsAre(2, 3));
+ EXPECT_EQ(&ref, &*a);
+ }
+
+ {
+ Optional<std::vector<int>> a;
+ auto& ref = a.emplace({4, 5}, std::allocator<int>());
+ static_assert(std::is_same<std::vector<int>&, decltype(ref)>::value, "");
+ EXPECT_TRUE(a);
+ EXPECT_THAT(*a, ElementsAre(4, 5));
+ EXPECT_EQ(&ref, &*a);
+ }
+}
+
+TEST(OptionalTest, Equals_TwoEmpty) {
+ Optional<int> a;
+ Optional<int> b;
+
+ EXPECT_TRUE(a == b);
+}
+
+TEST(OptionalTest, Equals_TwoEquals) {
+ Optional<int> a(1);
+ Optional<int> b(1);
+
+ EXPECT_TRUE(a == b);
+}
+
+TEST(OptionalTest, Equals_OneEmpty) {
+ Optional<int> a;
+ Optional<int> b(1);
+
+ EXPECT_FALSE(a == b);
+}
+
+TEST(OptionalTest, Equals_TwoDifferent) {
+ Optional<int> a(0);
+ Optional<int> b(1);
+
+ EXPECT_FALSE(a == b);
+}
+
+TEST(OptionalTest, Equals_DifferentType) {
+ Optional<int> a(0);
+ Optional<double> b(0);
+
+ EXPECT_TRUE(a == b);
+}
+
+TEST(OptionalTest, NotEquals_TwoEmpty) {
+ Optional<int> a;
+ Optional<int> b;
+
+ EXPECT_FALSE(a != b);
+}
+
+TEST(OptionalTest, NotEquals_TwoEquals) {
+ Optional<int> a(1);
+ Optional<int> b(1);
+
+ EXPECT_FALSE(a != b);
+}
+
+TEST(OptionalTest, NotEquals_OneEmpty) {
+ Optional<int> a;
+ Optional<int> b(1);
+
+ EXPECT_TRUE(a != b);
+}
+
+TEST(OptionalTest, NotEquals_TwoDifferent) {
+ Optional<int> a(0);
+ Optional<int> b(1);
+
+ EXPECT_TRUE(a != b);
+}
+
+TEST(OptionalTest, NotEquals_DifferentType) {
+ Optional<int> a(0);
+ Optional<double> b(0.0);
+
+ EXPECT_FALSE(a != b);
+}
+
+TEST(OptionalTest, Less_LeftEmpty) {
+ Optional<int> l;
+ Optional<int> r(1);
+
+ EXPECT_TRUE(l < r);
+}
+
+TEST(OptionalTest, Less_RightEmpty) {
+ Optional<int> l(1);
+ Optional<int> r;
+
+ EXPECT_FALSE(l < r);
+}
+
+TEST(OptionalTest, Less_BothEmpty) {
+ Optional<int> l;
+ Optional<int> r;
+
+ EXPECT_FALSE(l < r);
+}
+
+TEST(OptionalTest, Less_BothValues) {
+ {
+ Optional<int> l(1);
+ Optional<int> r(2);
+
+ EXPECT_TRUE(l < r);
+ }
+ {
+ Optional<int> l(2);
+ Optional<int> r(1);
+
+ EXPECT_FALSE(l < r);
+ }
+ {
+ Optional<int> l(1);
+ Optional<int> r(1);
+
+ EXPECT_FALSE(l < r);
+ }
+}
+
+TEST(OptionalTest, Less_DifferentType) {
+ Optional<int> l(1);
+ Optional<double> r(2.0);
+
+ EXPECT_TRUE(l < r);
+}
+
+TEST(OptionalTest, LessEq_LeftEmpty) {
+ Optional<int> l;
+ Optional<int> r(1);
+
+ EXPECT_TRUE(l <= r);
+}
+
+TEST(OptionalTest, LessEq_RightEmpty) {
+ Optional<int> l(1);
+ Optional<int> r;
+
+ EXPECT_FALSE(l <= r);
+}
+
+TEST(OptionalTest, LessEq_BothEmpty) {
+ Optional<int> l;
+ Optional<int> r;
+
+ EXPECT_TRUE(l <= r);
+}
+
+TEST(OptionalTest, LessEq_BothValues) {
+ {
+ Optional<int> l(1);
+ Optional<int> r(2);
+
+ EXPECT_TRUE(l <= r);
+ }
+ {
+ Optional<int> l(2);
+ Optional<int> r(1);
+
+ EXPECT_FALSE(l <= r);
+ }
+ {
+ Optional<int> l(1);
+ Optional<int> r(1);
+
+ EXPECT_TRUE(l <= r);
+ }
+}
+
+TEST(OptionalTest, LessEq_DifferentType) {
+ Optional<int> l(1);
+ Optional<double> r(2.0);
+
+ EXPECT_TRUE(l <= r);
+}
+
+TEST(OptionalTest, Greater_BothEmpty) {
+ Optional<int> l;
+ Optional<int> r;
+
+ EXPECT_FALSE(l > r);
+}
+
+TEST(OptionalTest, Greater_LeftEmpty) {
+ Optional<int> l;
+ Optional<int> r(1);
+
+ EXPECT_FALSE(l > r);
+}
+
+TEST(OptionalTest, Greater_RightEmpty) {
+ Optional<int> l(1);
+ Optional<int> r;
+
+ EXPECT_TRUE(l > r);
+}
+
+TEST(OptionalTest, Greater_BothValue) {
+ {
+ Optional<int> l(1);
+ Optional<int> r(2);
+
+ EXPECT_FALSE(l > r);
+ }
+ {
+ Optional<int> l(2);
+ Optional<int> r(1);
+
+ EXPECT_TRUE(l > r);
+ }
+ {
+ Optional<int> l(1);
+ Optional<int> r(1);
+
+ EXPECT_FALSE(l > r);
+ }
+}
+
+TEST(OptionalTest, Greater_DifferentType) {
+ Optional<int> l(1);
+ Optional<double> r(2.0);
+
+ EXPECT_FALSE(l > r);
+}
+
+TEST(OptionalTest, GreaterEq_BothEmpty) {
+ Optional<int> l;
+ Optional<int> r;
+
+ EXPECT_TRUE(l >= r);
+}
+
+TEST(OptionalTest, GreaterEq_LeftEmpty) {
+ Optional<int> l;
+ Optional<int> r(1);
+
+ EXPECT_FALSE(l >= r);
+}
+
+TEST(OptionalTest, GreaterEq_RightEmpty) {
+ Optional<int> l(1);
+ Optional<int> r;
+
+ EXPECT_TRUE(l >= r);
+}
+
+TEST(OptionalTest, GreaterEq_BothValue) {
+ {
+ Optional<int> l(1);
+ Optional<int> r(2);
+
+ EXPECT_FALSE(l >= r);
+ }
+ {
+ Optional<int> l(2);
+ Optional<int> r(1);
+
+ EXPECT_TRUE(l >= r);
+ }
+ {
+ Optional<int> l(1);
+ Optional<int> r(1);
+
+ EXPECT_TRUE(l >= r);
+ }
+}
+
+TEST(OptionalTest, GreaterEq_DifferentType) {
+ Optional<int> l(1);
+ Optional<double> r(2.0);
+
+ EXPECT_FALSE(l >= r);
+}
+
+TEST(OptionalTest, OptNullEq) {
+ {
+ Optional<int> opt;
+ EXPECT_TRUE(opt == base::nullopt);
+ }
+ {
+ Optional<int> opt(1);
+ EXPECT_FALSE(opt == base::nullopt);
+ }
+}
+
+TEST(OptionalTest, NullOptEq) {
+ {
+ Optional<int> opt;
+ EXPECT_TRUE(base::nullopt == opt);
+ }
+ {
+ Optional<int> opt(1);
+ EXPECT_FALSE(base::nullopt == opt);
+ }
+}
+
+TEST(OptionalTest, OptNullNotEq) {
+ {
+ Optional<int> opt;
+ EXPECT_FALSE(opt != base::nullopt);
+ }
+ {
+ Optional<int> opt(1);
+ EXPECT_TRUE(opt != base::nullopt);
+ }
+}
+
+TEST(OptionalTest, NullOptNotEq) {
+ {
+ Optional<int> opt;
+ EXPECT_FALSE(base::nullopt != opt);
+ }
+ {
+ Optional<int> opt(1);
+ EXPECT_TRUE(base::nullopt != opt);
+ }
+}
+
+TEST(OptionalTest, OptNullLower) {
+ {
+ Optional<int> opt;
+ EXPECT_FALSE(opt < base::nullopt);
+ }
+ {
+ Optional<int> opt(1);
+ EXPECT_FALSE(opt < base::nullopt);
+ }
+}
+
+TEST(OptionalTest, NullOptLower) {
+ {
+ Optional<int> opt;
+ EXPECT_FALSE(base::nullopt < opt);
+ }
+ {
+ Optional<int> opt(1);
+ EXPECT_TRUE(base::nullopt < opt);
+ }
+}
+
+TEST(OptionalTest, OptNullLowerEq) {
+ {
+ Optional<int> opt;
+ EXPECT_TRUE(opt <= base::nullopt);
+ }
+ {
+ Optional<int> opt(1);
+ EXPECT_FALSE(opt <= base::nullopt);
+ }
+}
+
+TEST(OptionalTest, NullOptLowerEq) {
+ {
+ Optional<int> opt;
+ EXPECT_TRUE(base::nullopt <= opt);
+ }
+ {
+ Optional<int> opt(1);
+ EXPECT_TRUE(base::nullopt <= opt);
+ }
+}
+
+TEST(OptionalTest, OptNullGreater) {
+ {
+ Optional<int> opt;
+ EXPECT_FALSE(opt > base::nullopt);
+ }
+ {
+ Optional<int> opt(1);
+ EXPECT_TRUE(opt > base::nullopt);
+ }
+}
+
+TEST(OptionalTest, NullOptGreater) {
+ {
+ Optional<int> opt;
+ EXPECT_FALSE(base::nullopt > opt);
+ }
+ {
+ Optional<int> opt(1);
+ EXPECT_FALSE(base::nullopt > opt);
+ }
+}
+
+TEST(OptionalTest, OptNullGreaterEq) {
+ {
+ Optional<int> opt;
+ EXPECT_TRUE(opt >= base::nullopt);
+ }
+ {
+ Optional<int> opt(1);
+ EXPECT_TRUE(opt >= base::nullopt);
+ }
+}
+
+TEST(OptionalTest, NullOptGreaterEq) {
+ {
+ Optional<int> opt;
+ EXPECT_TRUE(base::nullopt >= opt);
+ }
+ {
+ Optional<int> opt(1);
+ EXPECT_FALSE(base::nullopt >= opt);
+ }
+}
+
+TEST(OptionalTest, ValueEq_Empty) {
+ Optional<int> opt;
+ EXPECT_FALSE(opt == 1);
+}
+
+TEST(OptionalTest, ValueEq_NotEmpty) {
+ {
+ Optional<int> opt(0);
+ EXPECT_FALSE(opt == 1);
+ }
+ {
+ Optional<int> opt(1);
+ EXPECT_TRUE(opt == 1);
+ }
+}
+
+TEST(OptionalTest, ValueEq_DifferentType) {
+ Optional<int> opt(0);
+ EXPECT_TRUE(opt == 0.0);
+}
+
+TEST(OptionalTest, EqValue_Empty) {
+ Optional<int> opt;
+ EXPECT_FALSE(1 == opt);
+}
+
+TEST(OptionalTest, EqValue_NotEmpty) {
+ {
+ Optional<int> opt(0);
+ EXPECT_FALSE(1 == opt);
+ }
+ {
+ Optional<int> opt(1);
+ EXPECT_TRUE(1 == opt);
+ }
+}
+
+TEST(OptionalTest, EqValue_DifferentType) {
+ Optional<int> opt(0);
+ EXPECT_TRUE(0.0 == opt);
+}
+
+TEST(OptionalTest, ValueNotEq_Empty) {
+ Optional<int> opt;
+ EXPECT_TRUE(opt != 1);
+}
+
+TEST(OptionalTest, ValueNotEq_NotEmpty) {
+ {
+ Optional<int> opt(0);
+ EXPECT_TRUE(opt != 1);
+ }
+ {
+ Optional<int> opt(1);
+ EXPECT_FALSE(opt != 1);
+ }
+}
+
+TEST(OPtionalTest, ValueNotEq_DifferentType) {
+ Optional<int> opt(0);
+ EXPECT_FALSE(opt != 0.0);
+}
+
+TEST(OptionalTest, NotEqValue_Empty) {
+ Optional<int> opt;
+ EXPECT_TRUE(1 != opt);
+}
+
+TEST(OptionalTest, NotEqValue_NotEmpty) {
+ {
+ Optional<int> opt(0);
+ EXPECT_TRUE(1 != opt);
+ }
+ {
+ Optional<int> opt(1);
+ EXPECT_FALSE(1 != opt);
+ }
+}
+
+TEST(OptionalTest, NotEqValue_DifferentType) {
+ Optional<int> opt(0);
+ EXPECT_FALSE(0.0 != opt);
+}
+
+TEST(OptionalTest, ValueLess_Empty) {
+ Optional<int> opt;
+ EXPECT_TRUE(opt < 1);
+}
+
+TEST(OptionalTest, ValueLess_NotEmpty) {
+ {
+ Optional<int> opt(0);
+ EXPECT_TRUE(opt < 1);
+ }
+ {
+ Optional<int> opt(1);
+ EXPECT_FALSE(opt < 1);
+ }
+ {
+ Optional<int> opt(2);
+ EXPECT_FALSE(opt < 1);
+ }
+}
+
+TEST(OPtionalTest, ValueLess_DifferentType) {
+ Optional<int> opt(0);
+ EXPECT_TRUE(opt < 1.0);
+}
+
+TEST(OptionalTest, LessValue_Empty) {
+ Optional<int> opt;
+ EXPECT_FALSE(1 < opt);
+}
+
+TEST(OptionalTest, LessValue_NotEmpty) {
+ {
+ Optional<int> opt(0);
+ EXPECT_FALSE(1 < opt);
+ }
+ {
+ Optional<int> opt(1);
+ EXPECT_FALSE(1 < opt);
+ }
+ {
+ Optional<int> opt(2);
+ EXPECT_TRUE(1 < opt);
+ }
+}
+
+TEST(OptionalTest, LessValue_DifferentType) {
+ Optional<int> opt(0);
+ EXPECT_FALSE(0.0 < opt);
+}
+
+TEST(OptionalTest, ValueLessEq_Empty) {
+ Optional<int> opt;
+ EXPECT_TRUE(opt <= 1);
+}
+
+TEST(OptionalTest, ValueLessEq_NotEmpty) {
+ {
+ Optional<int> opt(0);
+ EXPECT_TRUE(opt <= 1);
+ }
+ {
+ Optional<int> opt(1);
+ EXPECT_TRUE(opt <= 1);
+ }
+ {
+ Optional<int> opt(2);
+ EXPECT_FALSE(opt <= 1);
+ }
+}
+
+TEST(OptionalTest, ValueLessEq_DifferentType) {
+ Optional<int> opt(0);
+ EXPECT_TRUE(opt <= 0.0);
+}
+
+TEST(OptionalTest, LessEqValue_Empty) {
+ Optional<int> opt;
+ EXPECT_FALSE(1 <= opt);
+}
+
+TEST(OptionalTest, LessEqValue_NotEmpty) {
+ {
+ Optional<int> opt(0);
+ EXPECT_FALSE(1 <= opt);
+ }
+ {
+ Optional<int> opt(1);
+ EXPECT_TRUE(1 <= opt);
+ }
+ {
+ Optional<int> opt(2);
+ EXPECT_TRUE(1 <= opt);
+ }
+}
+
+TEST(OptionalTest, LessEqValue_DifferentType) {
+ Optional<int> opt(0);
+ EXPECT_TRUE(0.0 <= opt);
+}
+
+TEST(OptionalTest, ValueGreater_Empty) {
+ Optional<int> opt;
+ EXPECT_FALSE(opt > 1);
+}
+
+TEST(OptionalTest, ValueGreater_NotEmpty) {
+ {
+ Optional<int> opt(0);
+ EXPECT_FALSE(opt > 1);
+ }
+ {
+ Optional<int> opt(1);
+ EXPECT_FALSE(opt > 1);
+ }
+ {
+ Optional<int> opt(2);
+ EXPECT_TRUE(opt > 1);
+ }
+}
+
+TEST(OptionalTest, ValueGreater_DifferentType) {
+ Optional<int> opt(0);
+ EXPECT_FALSE(opt > 0.0);
+}
+
+TEST(OptionalTest, GreaterValue_Empty) {
+ Optional<int> opt;
+ EXPECT_TRUE(1 > opt);
+}
+
+TEST(OptionalTest, GreaterValue_NotEmpty) {
+ {
+ Optional<int> opt(0);
+ EXPECT_TRUE(1 > opt);
+ }
+ {
+ Optional<int> opt(1);
+ EXPECT_FALSE(1 > opt);
+ }
+ {
+ Optional<int> opt(2);
+ EXPECT_FALSE(1 > opt);
+ }
+}
+
+TEST(OptionalTest, GreaterValue_DifferentType) {
+ Optional<int> opt(0);
+ EXPECT_FALSE(0.0 > opt);
+}
+
+TEST(OptionalTest, ValueGreaterEq_Empty) {
+ Optional<int> opt;
+ EXPECT_FALSE(opt >= 1);
+}
+
+TEST(OptionalTest, ValueGreaterEq_NotEmpty) {
+ {
+ Optional<int> opt(0);
+ EXPECT_FALSE(opt >= 1);
+ }
+ {
+ Optional<int> opt(1);
+ EXPECT_TRUE(opt >= 1);
+ }
+ {
+ Optional<int> opt(2);
+ EXPECT_TRUE(opt >= 1);
+ }
+}
+
+TEST(OptionalTest, ValueGreaterEq_DifferentType) {
+ Optional<int> opt(0);
+ EXPECT_TRUE(opt <= 0.0);
+}
+
+TEST(OptionalTest, GreaterEqValue_Empty) {
+ Optional<int> opt;
+ EXPECT_TRUE(1 >= opt);
+}
+
+TEST(OptionalTest, GreaterEqValue_NotEmpty) {
+ {
+ Optional<int> opt(0);
+ EXPECT_TRUE(1 >= opt);
+ }
+ {
+ Optional<int> opt(1);
+ EXPECT_TRUE(1 >= opt);
+ }
+ {
+ Optional<int> opt(2);
+ EXPECT_FALSE(1 >= opt);
+ }
+}
+
+TEST(OptionalTest, GreaterEqValue_DifferentType) {
+ Optional<int> opt(0);
+ EXPECT_TRUE(0.0 >= opt);
+}
+
+TEST(OptionalTest, NotEquals) {
+ {
+ Optional<float> a(0.1f);
+ Optional<float> b(0.2f);
+ EXPECT_NE(a, b);
+ }
+
+ {
+ Optional<std::string> a("foo");
+ Optional<std::string> b("bar");
+ EXPECT_NE(a, b);
+ }
+
+ {
+ Optional<int> a(1);
+ Optional<double> b(2);
+ EXPECT_NE(a, b);
+ }
+
+ {
+ Optional<TestObject> a(TestObject(3, 0.1));
+ Optional<TestObject> b(TestObject(4, 1.0));
+ EXPECT_TRUE(a != b);
+ }
+}
+
+TEST(OptionalTest, NotEqualsNull) {
+ {
+ Optional<float> a(0.1f);
+ Optional<float> b(0.1f);
+ b = base::nullopt;
+ EXPECT_NE(a, b);
+ }
+
+ {
+ Optional<std::string> a("foo");
+ Optional<std::string> b("foo");
+ b = base::nullopt;
+ EXPECT_NE(a, b);
+ }
+
+ {
+ Optional<TestObject> a(TestObject(3, 0.1));
+ Optional<TestObject> b(TestObject(3, 0.1));
+ b = base::nullopt;
+ EXPECT_TRUE(a != b);
+ }
+}
+
+TEST(OptionalTest, MakeOptional) {
+ {
+ // Use qualified base::make_optional here and elsewhere to avoid the name
+ // confliction to std::make_optional.
+ // The name conflict happens only for types in std namespace, such as
+ // std::string. The other qualified base::make_optional usages are just for
+ // consistency.
+ Optional<float> o = base::make_optional(32.f);
+ EXPECT_TRUE(o);
+ EXPECT_EQ(32.f, *o);
+
+ float value = 3.f;
+ o = base::make_optional(std::move(value));
+ EXPECT_TRUE(o);
+ EXPECT_EQ(3.f, *o);
+ }
+
+ {
+ Optional<std::string> o = base::make_optional(std::string("foo"));
+ EXPECT_TRUE(o);
+ EXPECT_EQ("foo", *o);
+
+ std::string value = "bar";
+ o = base::make_optional(std::move(value));
+ EXPECT_TRUE(o);
+ EXPECT_EQ(std::string("bar"), *o);
+ }
+
+ {
+ Optional<TestObject> o = base::make_optional(TestObject(3, 0.1));
+ EXPECT_TRUE(!!o);
+ EXPECT_TRUE(TestObject(3, 0.1) == *o);
+
+ TestObject value = TestObject(0, 0.42);
+ o = base::make_optional(std::move(value));
+ EXPECT_TRUE(!!o);
+ EXPECT_TRUE(TestObject(0, 0.42) == *o);
+ EXPECT_EQ(TestObject::State::MOVED_FROM, value.state());
+ EXPECT_EQ(TestObject::State::MOVE_ASSIGNED, o->state());
+
+ EXPECT_EQ(TestObject::State::MOVE_CONSTRUCTED,
+ base::make_optional(std::move(value))->state());
+ }
+
+ {
+ struct Test {
+ Test(int x, double y, bool z) : a(x), b(y), c(z) {}
+
+ int a;
+ double b;
+ bool c;
+ };
+
+ Optional<Test> o = base::make_optional<Test>(1, 2.0, true);
+ EXPECT_TRUE(!!o);
+ EXPECT_EQ(1, o->a);
+ EXPECT_EQ(2.0, o->b);
+ EXPECT_TRUE(o->c);
+ }
+
+ {
+ auto str1 = base::make_optional<std::string>({'1', '2', '3'});
+ EXPECT_EQ("123", *str1);
+
+ auto str2 = base::make_optional<std::string>({'a', 'b', 'c'},
+ std::allocator<char>());
+ EXPECT_EQ("abc", *str2);
+ }
+}
+
+TEST(OptionalTest, NonMemberSwap_bothNoValue) {
+ Optional<TestObject> a, b;
+ base::swap(a, b);
+
+ EXPECT_FALSE(!!a);
+ EXPECT_FALSE(!!b);
+ EXPECT_TRUE(TestObject(42, 0.42) == a.value_or(TestObject(42, 0.42)));
+ EXPECT_TRUE(TestObject(42, 0.42) == b.value_or(TestObject(42, 0.42)));
+}
+
+TEST(OptionalTest, NonMemberSwap_inHasValue) {
+ Optional<TestObject> a(TestObject(1, 0.3));
+ Optional<TestObject> b;
+ base::swap(a, b);
+
+ EXPECT_FALSE(!!a);
+ EXPECT_TRUE(!!b);
+ EXPECT_TRUE(TestObject(42, 0.42) == a.value_or(TestObject(42, 0.42)));
+ EXPECT_TRUE(TestObject(1, 0.3) == b.value_or(TestObject(42, 0.42)));
+}
+
+TEST(OptionalTest, NonMemberSwap_outHasValue) {
+ Optional<TestObject> a;
+ Optional<TestObject> b(TestObject(1, 0.3));
+ base::swap(a, b);
+
+ EXPECT_TRUE(!!a);
+ EXPECT_FALSE(!!b);
+ EXPECT_TRUE(TestObject(1, 0.3) == a.value_or(TestObject(42, 0.42)));
+ EXPECT_TRUE(TestObject(42, 0.42) == b.value_or(TestObject(42, 0.42)));
+}
+
+TEST(OptionalTest, NonMemberSwap_bothValue) {
+ Optional<TestObject> a(TestObject(0, 0.1));
+ Optional<TestObject> b(TestObject(1, 0.3));
+ base::swap(a, b);
+
+ EXPECT_TRUE(!!a);
+ EXPECT_TRUE(!!b);
+ EXPECT_TRUE(TestObject(1, 0.3) == a.value_or(TestObject(42, 0.42)));
+ EXPECT_TRUE(TestObject(0, 0.1) == b.value_or(TestObject(42, 0.42)));
+ EXPECT_EQ(TestObject::State::SWAPPED, a->state());
+ EXPECT_EQ(TestObject::State::SWAPPED, b->state());
+}
+
+TEST(OptionalTest, Hash_OptionalReflectsInternal) {
+ {
+ std::hash<int> int_hash;
+ std::hash<Optional<int>> opt_int_hash;
+
+ EXPECT_EQ(int_hash(1), opt_int_hash(Optional<int>(1)));
+ }
+
+ {
+ std::hash<std::string> str_hash;
+ std::hash<Optional<std::string>> opt_str_hash;
+
+ EXPECT_EQ(str_hash(std::string("foobar")),
+ opt_str_hash(Optional<std::string>(std::string("foobar"))));
+ }
+}
+
+TEST(OptionalTest, Hash_NullOptEqualsNullOpt) {
+ std::hash<Optional<int>> opt_int_hash;
+ std::hash<Optional<std::string>> opt_str_hash;
+
+ EXPECT_EQ(opt_str_hash(Optional<std::string>()),
+ opt_int_hash(Optional<int>()));
+}
+
+TEST(OptionalTest, Hash_UseInSet) {
+ std::set<Optional<int>> setOptInt;
+
+ EXPECT_EQ(setOptInt.end(), setOptInt.find(42));
+
+ setOptInt.insert(Optional<int>(3));
+ EXPECT_EQ(setOptInt.end(), setOptInt.find(42));
+ EXPECT_NE(setOptInt.end(), setOptInt.find(3));
+}
+
+TEST(OptionalTest, HasValue) {
+ Optional<int> a;
+ EXPECT_FALSE(a.has_value());
+
+ a = 42;
+ EXPECT_TRUE(a.has_value());
+
+ a = nullopt;
+ EXPECT_FALSE(a.has_value());
+
+ a = 0;
+ EXPECT_TRUE(a.has_value());
+
+ a = Optional<int>();
+ EXPECT_FALSE(a.has_value());
+}
+
+TEST(OptionalTest, Reset_int) {
+ Optional<int> a(0);
+ EXPECT_TRUE(a.has_value());
+ EXPECT_EQ(0, a.value());
+
+ a.reset();
+ EXPECT_FALSE(a.has_value());
+ EXPECT_EQ(-1, a.value_or(-1));
+}
+
+TEST(OptionalTest, Reset_Object) {
+ Optional<TestObject> a(TestObject(0, 0.1));
+ EXPECT_TRUE(a.has_value());
+ EXPECT_EQ(TestObject(0, 0.1), a.value());
+
+ a.reset();
+ EXPECT_FALSE(a.has_value());
+ EXPECT_EQ(TestObject(42, 0.0), a.value_or(TestObject(42, 0.0)));
+}
+
+TEST(OptionalTest, Reset_NoOp) {
+ Optional<int> a;
+ EXPECT_FALSE(a.has_value());
+
+ a.reset();
+ EXPECT_FALSE(a.has_value());
+}
+
+TEST(OptionalTest, AssignFromRValue) {
+ Optional<TestObject> a;
+ EXPECT_FALSE(a.has_value());
+
+ TestObject obj;
+ a = std::move(obj);
+ EXPECT_TRUE(a.has_value());
+ EXPECT_EQ(1, a->move_ctors_count());
+}
+
+TEST(OptionalTest, DontCallDefaultCtor) {
+ Optional<DeletedDefaultConstructor> a;
+ EXPECT_FALSE(a.has_value());
+
+ a = base::make_optional<DeletedDefaultConstructor>(42);
+ EXPECT_TRUE(a.has_value());
+ EXPECT_EQ(42, a->foo());
+}
+
+TEST(OptionalTest, DontCallNewMemberFunction) {
+ Optional<DeleteNewOperators> a;
+ EXPECT_FALSE(a.has_value());
+
+ a = DeleteNewOperators();
+ EXPECT_TRUE(a.has_value());
+}
+
+TEST(OptionalTest, Noexcept) {
+ // Trivial copy ctor, non-trivial move ctor, nothrow move assign.
+ struct Test1 {
+ Test1(const Test1&) = default;
+ Test1(Test1&&) {}
+ Test1& operator=(Test1&&) = default;
+ };
+ // Non-trivial copy ctor, trivial move ctor, throw move assign.
+ struct Test2 {
+ Test2(const Test2&) {}
+ Test2(Test2&&) = default;
+ Test2& operator=(Test2&&) { return *this; }
+ };
+ // Trivial copy ctor, non-trivial nothrow move ctor.
+ struct Test3 {
+ Test3(const Test3&) = default;
+ Test3(Test3&&) noexcept {}
+ };
+ // Non-trivial copy ctor, non-trivial nothrow move ctor.
+ struct Test4 {
+ Test4(const Test4&) {}
+ Test4(Test4&&) noexcept {}
+ };
+ // Non-trivial copy ctor, non-trivial move ctor.
+ struct Test5 {
+ Test5(const Test5&) {}
+ Test5(Test5&&) {}
+ };
+
+ static_assert(
+ noexcept(Optional<int>(std::declval<Optional<int>>())),
+ "move constructor for noexcept move-constructible T must be noexcept "
+ "(trivial copy, trivial move)");
+ static_assert(
+ !noexcept(Optional<Test1>(std::declval<Optional<Test1>>())),
+ "move constructor for non-noexcept move-constructible T must not be "
+ "noexcept (trivial copy)");
+ static_assert(
+ noexcept(Optional<Test2>(std::declval<Optional<Test2>>())),
+ "move constructor for noexcept move-constructible T must be noexcept "
+ "(non-trivial copy, trivial move)");
+ static_assert(
+ noexcept(Optional<Test3>(std::declval<Optional<Test3>>())),
+ "move constructor for noexcept move-constructible T must be noexcept "
+ "(trivial copy, non-trivial move)");
+ static_assert(
+ noexcept(Optional<Test4>(std::declval<Optional<Test4>>())),
+ "move constructor for noexcept move-constructible T must be noexcept "
+ "(non-trivial copy, non-trivial move)");
+ static_assert(
+ !noexcept(Optional<Test5>(std::declval<Optional<Test5>>())),
+ "move constructor for non-noexcept move-constructible T must not be "
+ "noexcept (non-trivial copy)");
+
+ static_assert(
+ noexcept(std::declval<Optional<int>>() = std::declval<Optional<int>>()),
+ "move assign for noexcept move-constructible/move-assignable T "
+ "must be noexcept");
+ static_assert(
+ !noexcept(std::declval<Optional<Test1>>() =
+ std::declval<Optional<Test1>>()),
+ "move assign for non-noexcept move-constructible T must not be noexcept");
+ static_assert(
+ !noexcept(std::declval<Optional<Test2>>() =
+ std::declval<Optional<Test2>>()),
+ "move assign for non-noexcept move-assignable T must not be noexcept");
+}
+
+} // namespace base
+} // namespace perfetto
+
+#pragma GCC diagnostic pop