mirror of
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564 lines
20 KiB
C++
564 lines
20 KiB
C++
// Copyright (c) 2023-2024, The Monero Project
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//
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// All rights reserved.
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//
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// Redistribution and use in source and binary forms, with or without modification, are
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// permitted provided that the following conditions are met:
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//
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// 1. Redistributions of source code must retain the above copyright notice, this list of
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// conditions and the following disclaimer.
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//
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// 2. Redistributions in binary form must reproduce the above copyright notice, this list
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// of conditions and the following disclaimer in the documentation and/or other
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// materials provided with the distribution.
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//
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// 3. Neither the name of the copyright holder nor the names of its contributors may be
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// used to endorse or promote products derived from this software without specific
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// prior written permission.
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//
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// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY
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// EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
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// MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL
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// THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
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// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
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// PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
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// INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
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// STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF
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// THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
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#include "common/variant.h"
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#include <boost/mpl/deref.hpp>
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#include <boost/variant/recursive_wrapper.hpp>
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#include <boost/variant/recursive_variant.hpp>
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#include "gtest/gtest.h"
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#include <sstream>
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#include <type_traits>
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#include <vector>
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using tools::optional_variant;
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using tools::variant;
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using tools::variant_static_visitor;
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namespace
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{
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//-------------------------------------------------------------------------------------------------------------------
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//-------------------------------------------------------------------------------------------------------------------
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template <typename T>
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using strip_all_t = std::remove_reference_t<std::remove_cv_t<T>>;
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//-------------------------------------------------------------------------------------------------------------------
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//-------------------------------------------------------------------------------------------------------------------
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template <typename T, typename U>
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using strip_same = std::is_same<strip_all_t<T>, strip_all_t<U>>;
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//-------------------------------------------------------------------------------------------------------------------
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//-------------------------------------------------------------------------------------------------------------------
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template
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<
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typename PositiveType,
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typename TestType,
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typename... VariantTypes,
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class VecTypes = boost::mpl::vector<VariantTypes...>,
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class VecBegin = typename boost::mpl::begin<VecTypes>::type,
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class VecIndexT = typename boost::mpl::find<VecTypes, TestType>::type,
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size_t TYPE_INDEX = boost::mpl::distance<VecBegin, VecIndexT>::value,
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bool LAST_VARIANT_TYPE = TYPE_INDEX == sizeof...(VariantTypes) - 1
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>
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static std::enable_if_t<LAST_VARIANT_TYPE>
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test_is_type_match(const variant<VariantTypes...>& v)
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{
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constexpr bool expected = strip_same<PositiveType, TestType>();
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const bool actual = v.template is_type<TestType>();
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EXPECT_EQ(expected, actual);
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EXPECT_FALSE(v.template is_type<boost::blank>());
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}
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//-------------------------------------------------------------------------------------------------------------------
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//-------------------------------------------------------------------------------------------------------------------
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template
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<
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typename PositiveType,
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typename TestType,
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typename... VariantTypes,
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class VecTypes = boost::mpl::vector<VariantTypes...>,
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class VecBegin = typename boost::mpl::begin<VecTypes>::type,
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class VecIndexT = typename boost::mpl::find<VecTypes, TestType>::type,
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size_t TYPE_INDEX = boost::mpl::distance<VecBegin, VecIndexT>::value,
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bool LAST_VARIANT_TYPE = TYPE_INDEX == sizeof...(VariantTypes) - 1
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>
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static std::enable_if_t<!LAST_VARIANT_TYPE>
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test_is_type_match(const variant<VariantTypes...>& v)
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{
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constexpr bool expected = strip_same<PositiveType, TestType>();
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const bool actual = v.template is_type<TestType>();
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EXPECT_EQ(expected, actual);
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using NextTypeIt = typename boost::mpl::advance<VecIndexT, boost::mpl::int_<1>>::type;
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using NextTestType = typename boost::mpl::deref<NextTypeIt>::type;
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test_is_type_match<PositiveType, NextTestType>(v);
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}
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//-------------------------------------------------------------------------------------------------------------------
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//-------------------------------------------------------------------------------------------------------------------
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template
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<
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typename VariantType0,
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typename... VariantTypesRest,
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typename AssignType
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>
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static void test_is_type_ref
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(
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variant<VariantType0, VariantTypesRest...>& v,
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AssignType&& val
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)
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{
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v = val;
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test_is_type_match<AssignType, VariantType0>(v);
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}
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//-------------------------------------------------------------------------------------------------------------------
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//-------------------------------------------------------------------------------------------------------------------
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template
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<
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typename VariantType0,
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typename... VariantTypesRest,
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typename AssignType0,
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typename... AssignTypesRest
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>
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static void test_is_type_ref
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(
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variant<VariantType0, VariantTypesRest...>& v,
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AssignType0&& val_0,
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AssignTypesRest&&... val_rest
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)
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{
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v = val_0;
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test_is_type_match<AssignType0, VariantType0>(v);
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test_is_type_ref(v, val_rest...);
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}
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//-------------------------------------------------------------------------------------------------------------------
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//-------------------------------------------------------------------------------------------------------------------
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template <typename... VariantTypes>
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static void test_is_type_full(VariantTypes&&... test_vals)
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{
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variant<VariantTypes...> v;
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test_is_type_ref(v, test_vals...);
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}
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//-------------------------------------------------------------------------------------------------------------------
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//-------------------------------------------------------------------------------------------------------------------
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template
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<
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size_t IJ = 0,
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typename... VariantTypes,
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bool END = IJ == sizeof...(VariantTypes) * sizeof...(VariantTypes)
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>
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static std::enable_if_t<END>
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test_same_type_ref
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(
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variant<VariantTypes...>& v1,
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variant<VariantTypes...>& v2,
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const std::tuple<VariantTypes...>& tup_i,
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const std::tuple<VariantTypes...>& tup_j
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)
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{ /* trivial end case */ }
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//-------------------------------------------------------------------------------------------------------------------
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//-------------------------------------------------------------------------------------------------------------------
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template
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<
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size_t IJ = 0,
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typename... VariantTypes,
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bool END = IJ == sizeof...(VariantTypes) * sizeof...(VariantTypes)
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>
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static std::enable_if_t<!END>
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test_same_type_ref
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(
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variant<VariantTypes...>& v1,
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variant<VariantTypes...>& v2,
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const std::tuple<VariantTypes...>& tup_i,
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const std::tuple<VariantTypes...>& tup_j
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)
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{
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constexpr size_t I = IJ / sizeof...(VariantTypes);
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constexpr size_t J = IJ % sizeof...(VariantTypes);
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constexpr bool expected = I == J;
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v1 = std::get<I>(tup_i);
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v2 = std::get<J>(tup_j);
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const bool actual = variant<VariantTypes...>::same_type(v1, v2);
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EXPECT_EQ(expected, actual);
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test_same_type_ref<IJ + 1>(v1, v2, tup_i, tup_j);
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}
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//-------------------------------------------------------------------------------------------------------------------
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//-------------------------------------------------------------------------------------------------------------------
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template <typename... VariantTypes>
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static void test_same_type_full
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(
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const std::tuple<VariantTypes...>& vals_i,
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const std::tuple<VariantTypes...>& vals_j
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)
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{
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using Variant = variant<VariantTypes...>;
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Variant v_i;
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Variant v_j;
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test_same_type_ref(v_i, v_j, vals_i, vals_j);
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}
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//-------------------------------------------------------------------------------------------------------------------
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//-------------------------------------------------------------------------------------------------------------------
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struct test_stringify_visitor: public variant_static_visitor<std::string>
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{
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template <typename T>
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static std::string stringify(const T& t)
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{
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std::stringstream ss;
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ss << typeid(T).name();
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ss << "::";
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ss << t;
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return ss.str();
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}
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template <class Variant, typename T>
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static void test_visitation(const Variant& v, const T& t)
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{
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EXPECT_EQ(test_stringify_visitor::stringify(t), v.visit(test_stringify_visitor()));
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}
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// Make sure boost::blank errors
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using variant_static_visitor::operator();
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// Visitation implementation
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template <typename T>
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std::string operator()(const T& t) const
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{
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return test_stringify_visitor::stringify(t);
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}
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};
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//-------------------------------------------------------------------------------------------------------------------
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//-------------------------------------------------------------------------------------------------------------------
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} // anonymous namespace
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//-------------------------------------------------------------------------------------------------------------------
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TEST(variant, operatorbool)
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{
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optional_variant<int8_t, uint8_t, int16_t, uint16_t, std::string> v;
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EXPECT_FALSE(v);
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v = (int16_t) 2023;
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EXPECT_TRUE(v);
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v = (int16_t) 0;
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EXPECT_TRUE(v);
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v = boost::blank{};
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EXPECT_FALSE(v);
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}
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//-------------------------------------------------------------------------------------------------------------------
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TEST(variant, is_empty)
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{
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optional_variant<int8_t, uint8_t, int16_t, uint16_t, std::string> v;
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EXPECT_TRUE(v.is_empty());
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v = (int16_t) 2023;
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EXPECT_FALSE(v.is_empty());
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v = (int16_t) 0;
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EXPECT_FALSE(v.is_empty());
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v = boost::blank{};
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EXPECT_TRUE(v.is_empty());
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optional_variant<> v2;
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EXPECT_TRUE(v2.is_empty());
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v2 = boost::blank{};
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EXPECT_TRUE(v2.is_empty());
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}
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//-------------------------------------------------------------------------------------------------------------------
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TEST(variant, is_type)
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{
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variant<int8_t, uint8_t, int16_t, uint16_t, std::string> v;
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EXPECT_TRUE(v.is_type<int8_t>());
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v = (int16_t) 2023;
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EXPECT_TRUE(v.is_type<int16_t>());
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test_is_type_full((uint32_t) 2023, (char) '\n', std::string("HOWDY"));
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}
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//-------------------------------------------------------------------------------------------------------------------
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TEST(variant, try_unwrap)
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{
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variant<int8_t, uint8_t, int16_t, uint16_t, std::string> v;
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EXPECT_TRUE(v.try_unwrap<int8_t>());
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v = (int16_t) 5252;
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ASSERT_TRUE(v.try_unwrap<int16_t>());
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EXPECT_EQ(5252, *v.try_unwrap<int16_t>());
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EXPECT_FALSE(v.try_unwrap<uint16_t>());
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EXPECT_FALSE(v.try_unwrap<std::string>());
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}
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//-------------------------------------------------------------------------------------------------------------------
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TEST(variant, unwrap)
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{
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variant<int8_t, uint8_t, int16_t, uint16_t, std::string> v;
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EXPECT_EQ(0, v.unwrap<int8_t>());
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v = (int16_t) 5252;
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EXPECT_EQ(5252, v.unwrap<int16_t>());
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EXPECT_THROW(v.unwrap<uint16_t>(), std::runtime_error);
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EXPECT_THROW(v.unwrap<std::string>(), std::runtime_error);
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}
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//-------------------------------------------------------------------------------------------------------------------
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TEST(variant, mutation)
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{
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variant<uint8_t> v;
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v = (uint8_t) 5;
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EXPECT_EQ(5, v.unwrap<uint8_t>());
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uint8_t &intref{v.unwrap<uint8_t>()};
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intref = 10;
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EXPECT_EQ(10, v.unwrap<uint8_t>());
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EXPECT_TRUE(v.try_unwrap<uint8_t>());
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uint8_t *intptr{v.try_unwrap<uint8_t>()};
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*intptr = 15;
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EXPECT_EQ(15, v.unwrap<uint8_t>());
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const variant<uint8_t> &v_ref{v};
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EXPECT_EQ(15, v_ref.unwrap<uint8_t>());
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EXPECT_TRUE(v_ref.try_unwrap<uint8_t>());
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EXPECT_EQ(15, *(v_ref.try_unwrap<uint8_t>()));
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}
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//-------------------------------------------------------------------------------------------------------------------
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TEST(variant, index)
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{
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variant<int8_t, uint8_t, int16_t, uint16_t, std::string> v;
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EXPECT_EQ(0, v.index());
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v = (int8_t) 7;
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EXPECT_EQ(0, v.index());
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v = (uint8_t) 7;
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EXPECT_EQ(1, v.index());
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v = (int16_t) 7;
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EXPECT_EQ(2, v.index());
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v = (uint16_t) 7;
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EXPECT_EQ(3, v.index());
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v = "verifiable variant vying for vengence versus visa";
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EXPECT_EQ(4, v.index());
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optional_variant<int8_t, uint8_t, int16_t, uint16_t, std::string> vo;
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EXPECT_EQ(0, vo.index());
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vo = (int8_t) 7;
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EXPECT_EQ(1, vo.index());
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vo = (uint8_t) 7;
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EXPECT_EQ(2, vo.index());
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vo = (int16_t) 7;
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EXPECT_EQ(3, vo.index());
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vo = (uint16_t) 7;
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EXPECT_EQ(4, vo.index());
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vo = "verifiable variant vying for vengence versus visa";
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EXPECT_EQ(5, vo.index());
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}
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//-------------------------------------------------------------------------------------------------------------------
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TEST(variant, type_index_of)
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{
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variant<int8_t, uint8_t, int16_t, uint16_t, std::string> v;
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EXPECT_EQ(0, decltype(v)::type_index_of<int8_t>());
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EXPECT_EQ(1, decltype(v)::type_index_of<uint8_t>());
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EXPECT_EQ(2, decltype(v)::type_index_of<int16_t>());
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EXPECT_EQ(3, decltype(v)::type_index_of<uint16_t>());
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EXPECT_EQ(4, decltype(v)::type_index_of<std::string>());
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optional_variant<int8_t, uint8_t, int16_t, uint16_t, std::string> vo;
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EXPECT_EQ(0, decltype(vo)::type_index_of<boost::blank>());
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EXPECT_EQ(1, decltype(vo)::type_index_of<int8_t>());
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EXPECT_EQ(2, decltype(vo)::type_index_of<uint8_t>());
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EXPECT_EQ(3, decltype(vo)::type_index_of<int16_t>());
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EXPECT_EQ(4, decltype(vo)::type_index_of<uint16_t>());
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EXPECT_EQ(5, decltype(vo)::type_index_of<std::string>());
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}
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//-------------------------------------------------------------------------------------------------------------------
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TEST(variant, constexpr_type_index_of)
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{
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variant<int8_t, uint8_t, int16_t, uint16_t, std::string> v;
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constexpr int TINDEX2 = decltype(v)::type_index_of<int16_t>();
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EXPECT_EQ(2, TINDEX2);
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constexpr int TINDEX4 = decltype(v)::type_index_of<std::string>();
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EXPECT_EQ(4, TINDEX4);
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}
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//-------------------------------------------------------------------------------------------------------------------
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TEST(variant, same_type)
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{
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const std::tuple<int, std::string, char> vals_i(77840, "Hullubaloo", '\0');
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const std::tuple<int, std::string, char> vals_j(1876, "Canneck", '\t');
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test_same_type_full(vals_i, vals_j);
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}
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//-------------------------------------------------------------------------------------------------------------------
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TEST(variant, visit)
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{
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variant<int8_t, uint8_t, int16_t, uint16_t, std::string> v;
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v = "Rev";
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test_stringify_visitor::test_visitation(v, std::string("Rev"));
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v = (int16_t) 2001;
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test_stringify_visitor::test_visitation(v, (int16_t) 2001);
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EXPECT_NE(test_stringify_visitor::stringify((uint16_t) 2001), v.visit(test_stringify_visitor()));
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}
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//-------------------------------------------------------------------------------------------------------------------
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TEST(variant, visit_lambda)
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{
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const auto stringify_lambda = [](auto x) -> std::string
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{
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if constexpr (std::is_same_v<decltype(x), std::string>)
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return x;
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else if constexpr (std::is_same_v<decltype(x), boost::blank>)
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throw std::runtime_error("boost blank cannot be stringified");
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else
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return std::to_string(x);
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};
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variant<int8_t, uint8_t, int16_t, uint16_t, std::string> v;
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EXPECT_THROW(v.visit(stringify_lambda), std::runtime_error);
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v = "Rev";
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EXPECT_EQ("Rev", v.visit(stringify_lambda));
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v = (int16_t) 2001;
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EXPECT_EQ("2001", v.visit(stringify_lambda));
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}
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//-------------------------------------------------------------------------------------------------------------------
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TEST(variant, visit_ref_passthru)
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{
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struct A
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{
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int x;
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};
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struct B
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{
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int x;
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};
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struct x_ref_visitor: tools::variant_static_visitor<const int&>
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{
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using tools::variant_static_visitor<const int&>::operator();
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const int& operator()(const A &a) const { return a.x; }
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const int& operator()(const B &b) const { return b.x; }
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};
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tools::variant<A, B> v;
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EXPECT_THROW(v.visit(x_ref_visitor{}), std::runtime_error);
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// A very hairy looking test, but we're just testing that the reference returned from our static
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// visitor is actually pointing to something in the same stack space as our variant operand.
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// This will let us catch mistakes where we take a reference to a locally created variable if
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// the visit() method is changed subtlely.
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v = A { 2024 };
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const char * const px = reinterpret_cast<const char*>(std::addressof(v.visit(x_ref_visitor{})));
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const char * const pv = reinterpret_cast<const char*>(&v);
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EXPECT_LT(px - pv, sizeof(v));
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}
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//-------------------------------------------------------------------------------------------------------------------
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TEST(variant, value_initialize_to_type_index)
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{
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variant<int8_t, uint8_t, int16_t, uint16_t, std::string> v;
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for (int i = 0; i < 6; ++i)
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{
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v.value_initialize_to_type_index(i);
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EXPECT_EQ(i, v.index());
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}
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v = (int8_t) 69;
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EXPECT_EQ(1, v.index());
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EXPECT_EQ(69, v.unwrap<int8_t>());
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v.value_initialize_to_type_index(1);
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EXPECT_EQ(1, v.index());
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EXPECT_EQ(0, v.unwrap<int8_t>());
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v = (uint8_t) 69;
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EXPECT_EQ(2, v.index());
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EXPECT_EQ(69, v.unwrap<uint8_t>());
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v.value_initialize_to_type_index(2);
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EXPECT_EQ(2, v.index());
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EXPECT_EQ(0, v.unwrap<uint8_t>());
|
|
|
|
v = (int16_t) 69;
|
|
EXPECT_EQ(3, v.index());
|
|
EXPECT_EQ(69, v.unwrap<int16_t>());
|
|
v.value_initialize_to_type_index(3);
|
|
EXPECT_EQ(3, v.index());
|
|
EXPECT_EQ(0, v.unwrap<int16_t>());
|
|
|
|
v = (uint16_t) 69;
|
|
EXPECT_EQ(4, v.index());
|
|
EXPECT_EQ(69, v.unwrap<uint16_t>());
|
|
v.value_initialize_to_type_index(4);
|
|
EXPECT_EQ(4, v.index());
|
|
EXPECT_EQ(0, v.unwrap<uint16_t>());
|
|
|
|
v = std::string("69");
|
|
EXPECT_EQ(5, v.index());
|
|
EXPECT_EQ("69", v.unwrap<std::string>());
|
|
v.value_initialize_to_type_index(5);
|
|
EXPECT_EQ(5, v.index());
|
|
EXPECT_EQ("", v.unwrap<std::string>());
|
|
|
|
v = (int16_t) 69;
|
|
v.value_initialize_to_type_index(5);
|
|
EXPECT_EQ("", v.unwrap<std::string>());
|
|
|
|
EXPECT_THROW(v.value_initialize_to_type_index(-1), std::runtime_error);
|
|
EXPECT_THROW(v.value_initialize_to_type_index(6), std::runtime_error);
|
|
}
|
|
//-------------------------------------------------------------------------------------------------------------------
|
|
TEST(variant, ad_hoc_recursion)
|
|
{
|
|
struct left_t;
|
|
struct right_t;
|
|
|
|
using twisty = optional_variant<boost::recursive_wrapper<left_t>, boost::recursive_wrapper<right_t>>;
|
|
|
|
struct left_t
|
|
{
|
|
twisty l;
|
|
};
|
|
|
|
struct right_t
|
|
{
|
|
twisty r;
|
|
};
|
|
|
|
auto right = [](twisty&& t = {}) -> twisty
|
|
{
|
|
right_t r;
|
|
r.r = t;
|
|
return r;
|
|
};
|
|
|
|
auto left = [](twisty&& t = {}) -> twisty
|
|
{
|
|
left_t l;
|
|
l.l = t;
|
|
return l;
|
|
};
|
|
|
|
struct twisty_counter: variant_static_visitor<std::pair<int, int>>
|
|
{
|
|
std::pair<int, int> operator()(boost::blank) const
|
|
{
|
|
return {0, 0};
|
|
}
|
|
|
|
std::pair<int, int> operator()(const left_t& l) const
|
|
{
|
|
auto count = l.l.visit(twisty_counter());
|
|
count.first += 1;
|
|
return count;
|
|
}
|
|
|
|
std::pair<int, int> operator()(const right_t& r) const
|
|
{
|
|
auto count = r.r.visit(twisty_counter());
|
|
count.second += 1;
|
|
return count;
|
|
}
|
|
};
|
|
|
|
const twisty tw = left(left(right(right(left(right(left(right(left()))))))));
|
|
|
|
int left_count, right_count;
|
|
std::tie(left_count, right_count) = tw.visit(twisty_counter());
|
|
|
|
EXPECT_EQ(5, left_count);
|
|
EXPECT_EQ(4, right_count);
|
|
}
|
|
//-------------------------------------------------------------------------------------------------------------------
|