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// Copyright 2017 The Chromium 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 MOJO_PUBLIC_CPP_BINDINGS_CLONE_TRAITS_H_
#define MOJO_PUBLIC_CPP_BINDINGS_CLONE_TRAITS_H_
#include <type_traits>
#include <vector>
#include "base/containers/flat_map.h"
#include "base/optional.h"
#include "mojo/public/cpp/bindings/lib/template_util.h"
namespace mojo {
template <typename T>
struct HasCloneMethod {
template <typename U>
static char Test(decltype(&U::Clone));
template <typename U>
static int Test(...);
static const bool value = sizeof(Test<T>(0)) == sizeof(char);
private:
internal::EnsureTypeIsComplete<T> check_t_;
};
template <typename T, bool has_clone_method = HasCloneMethod<T>::value>
struct CloneTraits;
template <typename T>
T Clone(const T& input);
template <typename T>
struct CloneTraits<T, true> {
static T Clone(const T& input) { return input.Clone(); }
};
template <typename T>
struct CloneTraits<T, false> {
static T Clone(const T& input) { return input; }
};
template <typename T>
struct CloneTraits<base::Optional<T>, false> {
static base::Optional<T> Clone(const base::Optional<T>& input) {
if (!input)
return base::nullopt;
return base::Optional<T>(mojo::Clone(*input));
}
};
template <typename T>
struct CloneTraits<std::vector<T>, false> {
static std::vector<T> Clone(const std::vector<T>& input) {
std::vector<T> result;
result.reserve(input.size());
for (const auto& element : input)
result.push_back(mojo::Clone(element));
return result;
}
};
template <typename K, typename V>
struct CloneTraits<base::flat_map<K, V>, false> {
static base::flat_map<K, V> Clone(const base::flat_map<K, V>& input) {
base::flat_map<K, V> result;
for (const auto& element : input) {
result.insert(std::make_pair(mojo::Clone(element.first),
mojo::Clone(element.second)));
}
return result;
}
};
template <typename T>
T Clone(const T& input) {
return CloneTraits<T>::Clone(input);
};
} // namespace mojo
#endif // MOJO_PUBLIC_CPP_BINDINGS_CLONE_TRAITS_H_