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fix: quantity_cast now correctly casts to an alias_unit

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Mateusz Pusz
2021-01-02 10:56:50 +01:00
parent b6ab340879
commit 6d7cda949e
3 changed files with 5 additions and 9 deletions
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8
src/include/units/quantity_cast.h
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@@ -106,25 +106,23 @@ template<Quantity To, typename D, typename U, scalable_with_<typename To::rep> R
requires QuantityOf<To, D>
[[nodiscard]] constexpr auto quantity_cast(const quantity<D, U, Rep>& q)
{
using ret_unit = downcast_unit<typename To::dimension, To::unit::ratio>;
using ret = quantity<typename To::dimension, ret_unit, typename To::rep>;
using traits = detail::cast_traits<Rep, typename To::rep>;
using ratio_type = TYPENAME traits::ratio_type;
using rep_type = TYPENAME traits::rep_type;
constexpr auto c_ratio = detail::cast_ratio(quantity<D, U, Rep>(), To());
if constexpr (treat_as_floating_point<rep_type>) {
return ret(static_cast<TYPENAME To::rep>(static_cast<rep_type>(q.count()) *
return To(static_cast<TYPENAME To::rep>(static_cast<rep_type>(q.count()) *
(static_cast<ratio_type>(c_ratio.num) * detail::fpow10<ratio_type>(c_ratio.exp) / static_cast<ratio_type>(c_ratio.den))));
}
else {
if constexpr (c_ratio.exp > 0) {
return ret(static_cast<TYPENAME To::rep>(static_cast<rep_type>(q.count()) *
return To(static_cast<TYPENAME To::rep>(static_cast<rep_type>(q.count()) *
(static_cast<ratio_type>(c_ratio.num) * static_cast<ratio_type>(detail::ipow10(c_ratio.exp))) /
static_cast<ratio_type>(c_ratio.den)));
}
else {
return ret(static_cast<TYPENAME To::rep>(static_cast<rep_type>(q.count()) *
return To(static_cast<TYPENAME To::rep>(static_cast<rep_type>(q.count()) *
static_cast<ratio_type>(c_ratio.num) /
(static_cast<ratio_type>(c_ratio.den) * static_cast<ratio_type>(detail::ipow10(-c_ratio.exp)))));
}

2
test/unit_test/static/quantity_point_test.cpp
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@@ -208,8 +208,6 @@ static_assert(std::equality_comparable_with<decltype(quantity_point(1_q_m)), dec
// quantity_cast
static_assert(compare<decltype(quantity_point_cast<scaled_unit<ratio(1), metre>>(quantity_point(2_q_km)))::unit, metre>);
static_assert(quantity_point_cast<quantity_point<dim_length, metre, int>>(quantity_point(2_q_km)).relative().count() ==
2000);
static_assert(

4
test/unit_test/static/quantity_test.cpp
View File

@@ -670,8 +670,6 @@ static_assert(2_q_dm3 + 2_q_cm3 == 2002_q_ml);
// quantity_cast
//////////////////
static_assert(compare<decltype(quantity_cast<scaled_unit<ratio(1), metre>>(2_q_km))::unit, metre>);
static_assert(quantity_cast<length<metre, int>>(2_q_km).count() == 2000);
static_assert(quantity_cast<length<kilometre, int>>(2000_q_m).count() == 2);
static_assert(quantity_cast<length<metre, int>>(1.23_q_m).count() == 1);
@@ -680,6 +678,8 @@ static_assert(quantity_cast<kilometre>(2000_q_m).count() == 2);
static_assert(quantity_cast<int>(1.23_q_m).count() == 1);
static_assert(quantity_cast<dim_speed, kilometre_per_hour>(2000.0_q_m / 3600.0_q_s).count() == 2);
static_assert(is_same_v<decltype(quantity_cast<litre>(2_q_dm3)), volume<litre, std::int64_t>>);
static_assert(!is_same_v<decltype(quantity_cast<litre>(2_q_dm3)), volume<cubic_decimetre, std::int64_t>>);
////////////////
// downcasting