Git-Mirrors/monero
1
0
Fork 0
mirror of https://github.com/monero-project/monero.git synced 2024-12-24 23:19:44 -05:00
Code Issues Packages Projects Releases Wiki Activity

Merge pull request #9176

Browse Source 
49ca1ad variant: split into variant and optional_variant (jeffro256)
This commit is contained in:
luigi1111 2024-12-23 10:19:55 -05:00
commit 1f7290f329
No known key found for this signature in database
GPG Key ID: F4ACA0183641E010
2 changed files with 77 additions and 34 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

45
src/common/variant.h
View File

@ -87,15 +87,14 @@ struct variant_static_visitor : public boost::static_visitor<ResultT>
};
template <typename... Types>
class variant final
class variant
{
using VType = boost::variant<boost::blank, Types...>;
using VType = boost::variant<Types...>;
public:
//constructors
/// default constructor
variant() = default;
variant(boost::none_t) : variant{} {} //act like boost::optional
/// construct from variant type (use enable_if to avoid issues with copy/move constructor)
template <typename T,
@ -108,14 +107,7 @@ public:
>::type = true>
variant(T &&value) : m_value{std::forward<T>(value)} {}
//overloaded operators
/// boolean operator: true if the variant isn't empty/uninitialized
explicit operator bool() const noexcept { return !this->is_empty(); }
//member functions
/// check if empty/uninitialized
bool is_empty() const noexcept { return m_value.which() == 0; }
/// check the variant type
template <typename T>
bool is_type() const noexcept { return this->index() == this->type_index_of<T>(); }
@ -149,7 +141,7 @@ public:
template <typename T>
static constexpr int type_index_of() noexcept
{
using types = boost::mpl::vector<boost::blank, Types...>;
using types = typename VType::types;
using elem = typename boost::mpl::find<types, T>::type;
using begin = typename boost::mpl::begin<types>::type;
return boost::mpl::distance<begin, elem>::value;
@ -187,4 +179,35 @@ private:
VType m_value;
};
template <typename... Types>
class optional_variant: public variant<boost::blank, Types...>
{
public:
//constructors
/// default constructor
optional_variant() = default;
/// construct from variant type (use enable_if to avoid issues with copy/move constructor)
template <typename T,
typename std::enable_if<
!std::is_same<
std::remove_cv_t<std::remove_reference_t<T>>,
optional_variant<Types...>
>::value,
bool
>::type = true>
optional_variant(T &&value) : variant<boost::blank, Types...>(std::forward<T>(value)) {}
// construct like boost::optional
optional_variant(boost::none_t) {}
//overloaded operators
/// boolean operator: true if the variant isn't empty/uninitialized
explicit operator bool() const noexcept { return !this->is_empty(); }
//member functions
/// check if empty/uninitialized
bool is_empty() const noexcept { return this->index() == 0; }
};
} //namespace tools

66
tests/unit_tests/variant.cpp
View File

@ -38,6 +38,7 @@
#include <type_traits>
#include <vector>
using tools::optional_variant;
using tools::variant;
using tools::variant_static_visitor;
@ -239,7 +240,7 @@ struct test_stringify_visitor: public variant_static_visitor<std::string>
//-------------------------------------------------------------------------------------------------------------------
TEST(variant, operatorbool)
{
variant<int8_t, uint8_t, int16_t, uint16_t, std::string> v;
optional_variant<int8_t, uint8_t, int16_t, uint16_t, std::string> v;
EXPECT_FALSE(v);
v = (int16_t) 2023;
EXPECT_TRUE(v);
@ -251,7 +252,7 @@ TEST(variant, operatorbool)
//-------------------------------------------------------------------------------------------------------------------
TEST(variant, is_empty)
{
variant<int8_t, uint8_t, int16_t, uint16_t, std::string> v;
optional_variant<int8_t, uint8_t, int16_t, uint16_t, std::string> v;
EXPECT_TRUE(v.is_empty());
v = (int16_t) 2023;
EXPECT_FALSE(v.is_empty());
@ -260,7 +261,7 @@ TEST(variant, is_empty)
v = boost::blank{};
EXPECT_TRUE(v.is_empty());
variant<> v2;
optional_variant<> v2;
EXPECT_TRUE(v2.is_empty());
v2 = boost::blank{};
EXPECT_TRUE(v2.is_empty());
@ -269,7 +270,7 @@ TEST(variant, is_empty)
TEST(variant, is_type)
{
variant<int8_t, uint8_t, int16_t, uint16_t, std::string> v;
EXPECT_TRUE(v.is_type<boost::blank>());
EXPECT_TRUE(v.is_type<int8_t>());
v = (int16_t) 2023;
EXPECT_TRUE(v.is_type<int16_t>());
@ -279,7 +280,7 @@ TEST(variant, is_type)
TEST(variant, try_unwrap)
{
variant<int8_t, uint8_t, int16_t, uint16_t, std::string> v;
EXPECT_FALSE(v.try_unwrap<int8_t>());
EXPECT_TRUE(v.try_unwrap<int8_t>());
v = (int16_t) 5252;
ASSERT_TRUE(v.try_unwrap<int16_t>());
EXPECT_EQ(5252, *v.try_unwrap<int16_t>());
@ -290,7 +291,7 @@ TEST(variant, try_unwrap)
TEST(variant, unwrap)
{
variant<int8_t, uint8_t, int16_t, uint16_t, std::string> v;
EXPECT_THROW(v.unwrap<int8_t>(), std::runtime_error);
EXPECT_EQ(0, v.unwrap<int8_t>());
v = (int16_t) 5252;
EXPECT_EQ(5252, v.unwrap<int16_t>());
EXPECT_THROW(v.unwrap<uint16_t>(), std::runtime_error);
@ -321,35 +322,55 @@ TEST(variant, index)
variant<int8_t, uint8_t, int16_t, uint16_t, std::string> v;
EXPECT_EQ(0, v.index());
v = (int8_t) 7;
EXPECT_EQ(1, v.index());
EXPECT_EQ(0, v.index());
v = (uint8_t) 7;
EXPECT_EQ(2, v.index());
EXPECT_EQ(1, v.index());
v = (int16_t) 7;
EXPECT_EQ(3, v.index());
EXPECT_EQ(2, v.index());
v = (uint16_t) 7;
EXPECT_EQ(4, v.index());
EXPECT_EQ(3, v.index());
v = "verifiable variant vying for vengence versus visa";
EXPECT_EQ(5, v.index());
EXPECT_EQ(4, v.index());
optional_variant<int8_t, uint8_t, int16_t, uint16_t, std::string> vo;
EXPECT_EQ(0, vo.index());
vo = (int8_t) 7;
EXPECT_EQ(1, vo.index());
vo = (uint8_t) 7;
EXPECT_EQ(2, vo.index());
vo = (int16_t) 7;
EXPECT_EQ(3, vo.index());
vo = (uint16_t) 7;
EXPECT_EQ(4, vo.index());
vo = "verifiable variant vying for vengence versus visa";
EXPECT_EQ(5, vo.index());
}
//-------------------------------------------------------------------------------------------------------------------
TEST(variant, type_index_of)
{
variant<int8_t, uint8_t, int16_t, uint16_t, std::string> v;
EXPECT_EQ(0, decltype(v)::type_index_of<boost::blank>());
EXPECT_EQ(1, decltype(v)::type_index_of<int8_t>());
EXPECT_EQ(2, decltype(v)::type_index_of<uint8_t>());
EXPECT_EQ(3, decltype(v)::type_index_of<int16_t>());
EXPECT_EQ(4, decltype(v)::type_index_of<uint16_t>());
EXPECT_EQ(5, decltype(v)::type_index_of<std::string>());
EXPECT_EQ(0, decltype(v)::type_index_of<int8_t>());
EXPECT_EQ(1, decltype(v)::type_index_of<uint8_t>());
EXPECT_EQ(2, decltype(v)::type_index_of<int16_t>());
EXPECT_EQ(3, decltype(v)::type_index_of<uint16_t>());
EXPECT_EQ(4, decltype(v)::type_index_of<std::string>());
optional_variant<int8_t, uint8_t, int16_t, uint16_t, std::string> vo;
EXPECT_EQ(0, decltype(vo)::type_index_of<boost::blank>());
EXPECT_EQ(1, decltype(vo)::type_index_of<int8_t>());
EXPECT_EQ(2, decltype(vo)::type_index_of<uint8_t>());
EXPECT_EQ(3, decltype(vo)::type_index_of<int16_t>());
EXPECT_EQ(4, decltype(vo)::type_index_of<uint16_t>());
EXPECT_EQ(5, decltype(vo)::type_index_of<std::string>());
}
//-------------------------------------------------------------------------------------------------------------------
TEST(variant, constexpr_type_index_of)
{
variant<int8_t, uint8_t, int16_t, uint16_t, std::string> v;
constexpr int TINDEX0 = decltype(v)::type_index_of<boost::blank>();
EXPECT_EQ(0, TINDEX0);
constexpr int TINDEX5 = decltype(v)::type_index_of<std::string>();
EXPECT_EQ(5, TINDEX5);
constexpr int TINDEX2 = decltype(v)::type_index_of<int16_t>();
EXPECT_EQ(2, TINDEX2);
constexpr int TINDEX4 = decltype(v)::type_index_of<std::string>();
EXPECT_EQ(4, TINDEX4);
}
//-------------------------------------------------------------------------------------------------------------------
TEST(variant, same_type)
@ -362,7 +383,6 @@ TEST(variant, same_type)
TEST(variant, visit)
{
variant<int8_t, uint8_t, int16_t, uint16_t, std::string> v;
EXPECT_THROW(v.visit(test_stringify_visitor()), std::runtime_error);
v = "Rev";
test_stringify_visitor::test_visitation(v, std::string("Rev"));
@ -484,7 +504,7 @@ TEST(variant, ad_hoc_recursion)
struct left_t;
struct right_t;
using twisty = variant<boost::recursive_wrapper<left_t>, boost::recursive_wrapper<right_t>>;
using twisty = optional_variant<boost::recursive_wrapper<left_t>, boost::recursive_wrapper<right_t>>;
struct left_t
{