Fix for #313 Corrected SFINAE for conversion constructors on span

This commit is contained in:
Neil MacIntosh 2016-09-13 12:19:19 -07:00 committed by GitHub
commit 6bc1e7e709
2 changed files with 12 additions and 41 deletions

View File

@ -123,23 +123,6 @@ namespace details
{
};
template <class From, class To>
struct is_allowed_pointer_conversion
: public std::integral_constant<bool, std::is_pointer<From>::value &&
std::is_pointer<To>::value &&
std::is_convertible<From, To>::value>
{
};
template <class From, class To>
struct is_allowed_integral_conversion
: public std::integral_constant<
bool, std::is_integral<From>::value && std::is_integral<To>::value &&
sizeof(From) == sizeof(To) && alignof(From) == alignof(To) &&
std::is_convertible<From, To>::value>
{
};
template <std::ptrdiff_t From, std::ptrdiff_t To>
struct is_allowed_extent_conversion
: public std::integral_constant<bool, From == To || From == gsl::dynamic_extent ||
@ -150,19 +133,7 @@ namespace details
template <class From, class To>
struct is_allowed_element_type_conversion
: public std::integral_constant<bool, std::is_same<From, std::remove_cv_t<To>>::value ||
is_allowed_pointer_conversion<From, To>::value ||
is_allowed_integral_conversion<From, To>::value>
{
};
template <class From>
struct is_allowed_element_type_conversion<From, byte>
: public std::integral_constant<bool, !std::is_const<From>::value>
{
};
template <class From>
struct is_allowed_element_type_conversion<From, const byte> : public std::true_type
std::is_convertible<From(*)[], To(*)[]>::value>
{
};
@ -449,7 +420,7 @@ public:
details::is_allowed_extent_conversion<OtherExtent, Extent>::value &&
details::is_allowed_element_type_conversion<OtherElementType, element_type>::value>>
constexpr span(const span<OtherElementType, OtherExtent>& other)
: storage_(reinterpret_cast<pointer>(other.data()),
: storage_(static_cast<pointer>(other.data()),
details::extent_type<OtherExtent>(other.size()))
{
}
@ -460,7 +431,7 @@ public:
details::is_allowed_extent_conversion<OtherExtent, Extent>::value &&
details::is_allowed_element_type_conversion<OtherElementType, element_type>::value>>
constexpr span(span<OtherElementType, OtherExtent>&& other)
: storage_(reinterpret_cast<pointer>(other.data()),
: storage_(static_cast<pointer>(other.data()),
details::extent_type<OtherExtent>(other.size()))
{
}

View File

@ -423,6 +423,7 @@ SUITE(span_tests)
span<const int, 4> s{arr};
CHECK(s.size() == narrow_cast<ptrdiff_t>(arr.size()) && s.data() == arr.data());
}
#ifdef CONFIRM_COMPILATION_ERRORS
{
span<const int, 2> s{arr};
@ -437,6 +438,7 @@ SUITE(span_tests)
{
span<const int, 5> s{arr};
}
#endif
{
auto get_an_array = []() -> const std::array<int, 4> { return {1, 2, 3, 4}; };
@ -444,7 +446,6 @@ SUITE(span_tests)
// try to take a temporary std::array
take_a_span(get_an_array());
}
#endif
}
TEST(from_std_array_const_constructor)
@ -460,6 +461,7 @@ SUITE(span_tests)
span<const int, 4> s{arr};
CHECK(s.size() == narrow_cast<ptrdiff_t>(arr.size()) && s.data() == arr.data());
}
#ifdef CONFIRM_COMPILATION_ERRORS
{
span<const int, 2> s{arr};
@ -509,7 +511,7 @@ SUITE(span_tests)
{
#ifdef CONFIRM_COMPILATION_ERRORS
span<char> s{cstr};
#endif
#endif
span<const char> cs{cstr};
CHECK(cs.size() == narrow_cast<std::ptrdiff_t>(cstr.size()) &&
cs.data() == cstr.data());
@ -520,7 +522,7 @@ SUITE(span_tests)
auto get_temp_vector = []() -> std::vector<int> { return {}; };
auto use_span = [](span<int> s) { static_cast<void>(s); };
use_span(get_temp_vector());
#endif
#endif
}
{
@ -534,7 +536,7 @@ SUITE(span_tests)
auto get_temp_string = []() -> std::string { return{}; };
auto use_span = [](span<char> s) { static_cast<void>(s); };
use_span(get_temp_string());
#endif
#endif
}
{
@ -552,11 +554,9 @@ SUITE(span_tests)
}
{
#ifdef CONFIRM_COMPILATION_ERRORS
auto get_temp_string = []() -> const std::string { return {}; };
auto use_span = [](span<const char> s) { static_cast<void>(s); };
use_span(get_temp_string());
#endif
}
{
@ -583,6 +583,7 @@ SUITE(span_tests)
#endif
}
#ifdef CONFIRM_COMPILATION_ERRORS
{
span<int> s;
span<unsigned int> s2 = s;
@ -596,12 +597,11 @@ SUITE(span_tests)
}
{
#ifdef CONFIRM_COMPILATION_ERRORS
span<int> s;
span<short> s2 = s;
static_cast<void>(s2);
#endif
}
#endif
}
TEST(copy_move_and_assignment)
@ -689,7 +689,7 @@ SUITE(span_tests)
span<int, 5> av = arr;
#ifdef CONFIRM_COMPILATION_ERRORS
CHECK(av.last<6>().length() == 6);
#endif
#endif
CHECK_THROW(av.last(6).length(), fail_fast);
}